JP2000321713A - Heat developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure such photographic characteristics as low fog, high sensitivity, high contrast, high blackening density and low Dmin by adjusting the number average particle size of photosensitive silver halide to a specified range and using a nucleus forming agent and a specified phenol derivative. SOLUTION: The heat developable photosensitive material has an image forming layer containing photosensitive silver halide having 0.01-0.12 μm number average particle size and at least one compound of the formula and at least one nucleus forming agent on the side is contained in the image forming layer. In the formula, R1-R3 are each H, halogen or a substituent bonding to the benzene ring by way of C, O, N, S or P and X1 and X2 are each H, halogen or a substituent bonding to the benzene ring by way of C or the like but at least one of X1 and X2 is a group of the formula -NR4R5 (where R4 and R5 are each H, alkyl or the like).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material, particularly to a photothermographic material for a scanner or an image setter suitable for photolithography. More specifically, the present invention provides
Low fog, high sensitivity and high contrast, high blackening density (D
max) which relates to a photothermographic material for photoengraving.

[0002]

2. Description of the Related Art There are many known photosensitive materials having a photosensitive layer on a support and forming an image by exposing the image. Among them, a technique for forming an image by thermal development is a system that can simplify environmental preservation and image forming means. In recent years, environmental preservation in the photoengraving field,
From the viewpoint of space saving, it is strongly desired to reduce the amount of processing waste liquid. There, you can use a laser scanner or a laser imagesetter to make the exposure more efficient,
There is a need for a technique relating to a photothermographic material for photolithography capable of forming a sharp black image having high resolution and sharpness. In these photothermographic materials,
By eliminating the use of solution processing chemicals, it is possible to provide customers with a simpler and more environmentally friendly thermal development processing system.

[0003] A method of forming an image by heat development is described in, for example, US Pat.
Morgan and B.A. "Thermal Proces Silver System (Thermally Proces)" by Shely
sed Silver Systems) A "(Imaging Processes and Materials
aterials) Neblette 8th edition, Sturge, V.E.
Walworth, A .; Shepp
Edited, page 2, 1969). Such photosensitive materials are prepared by dispersing a reducible non-photosensitive silver source (eg, an organic silver salt), a catalytically active amount of a photocatalyst (eg, silver halide), and a silver reducing agent, usually in an organic binder matrix. It is contained in. The photosensitive material is stable at room temperature, but when heated to a high temperature (for example, 80 ° C. or higher) after exposure, silver is reduced through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and a reducing agent. Generate This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure. The silver formed by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image. In addition, the photothermographic materials described above are conventionally known, but most of them form a photosensitive layer by applying a coating solution using an organic solvent such as toluene, methyl ethyl ketone (MEK) or methanol as a solvent. . The use of an organic solvent as a solvent is disadvantageous not only in adverse effects on the human body in the manufacturing process but also in cost due to recovery of the solvent and the like.

Therefore, a method of forming an image forming layer (hereinafter also referred to as "aqueous image forming layer") using a coating solution of a water solvent which does not have such a concern has been considered. For example,
JP-A-49-52626 and JP-A-53-116144 describe examples using gelatin as a binder. Also Japanese Patent Laid-Open No. 50-151
No. 138 describes an example using polyvinyl alcohol as a binder. Further, JP-A-60-61747 describes an example in which gelatin and polyvinyl alcohol are used in combination. As another example, JP-A-58-28737 describes an example of an image forming layer using water-soluble polyvinyl acetal as a binder. Certainly, when such a binder is used, the photosensitive layer can be formed using a coating solution of a water solvent, and the merits in terms of environment and cost are great. However, when a polymer such as gelatin, polyvinyl alcohol, or water-soluble polyacetal is used as a binder, the compatibility with an organic silver salt is poor, and not only a coated material that can be practically used on a coated surface cannot be obtained, but also the silver color of a developed portion Only those having a markedly impaired commercial value, such as brown or yellow whose tone is far from black which is originally preferable, and a low blackening density of an exposed portion and a high density of an unexposed portion were obtained.

EP-A-762,196 and JP-A-9-90550 disclose that a photosensitive silver halide grain used for a photothermographic material contains a group VII or VIII metal ion or a metal complex ion. It is disclosed that high contrast photographic characteristics can be obtained by incorporating a hydrazine derivative into a material. However, when a nucleating agent such as hydrazine is used in combination with the binder used in the above-mentioned aqueous solvent coating solution, a high-contrast image can be obtained. There is a problem that it is likely to occur and is not practical. On the other hand, the sensitivity is determined by the light sensitivity of the photosensitive silver halide grains and the number of photosensitive silver halide grains contained in the image forming layer. The higher the coating amount of the photosensitive silver halide, that is, the larger the number of grains, the higher the sensitivity, but there is a problem that Dmin increases. In addition, when a nucleating agent is used in combination, there is a problem that the sensitivity becomes lower as the environment during thermal development becomes lower in temperature and humidity. Therefore, a technology for providing a photothermographic material which is low in fog, has high sensitivity and high contrast, can obtain high blackening density (Dmax), and low photographic performance in Dmin, and is advantageous in terms of environment and cost is desired. Was rare.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems of the prior art. That is,
The present invention, especially for photoengraving, especially for scanners, imagesetters, low fog, high sensitivity and high contrast,
It was a first problem to be solved to provide a photothermographic material having a high blackening density (Dmax) and low Dmin and photographic characteristics. It is a second object of the present invention to provide a photothermographic material which can be applied in an aqueous system and is advantageous in terms of environment and cost.

[0007]

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have found that a photothermographic method having a non-photosensitive silver salt, a photosensitive silver halide and a binder on a support is provided. In the material, by adjusting the number average grain size of the photosensitive silver halide within the range of 0.01 μm or more and 0.12 μm or less, and simultaneously using the nucleating agent and the phenol derivative represented by the formula (A), Have found that it is possible to provide an excellent photothermographic material having desired effects,
The present invention has been provided. That is, according to the present invention, in a photothermographic material having a non-photosensitive silver salt, a photosensitive silver halide and a binder on a support, a photosensitive halogen having a number average particle size of 0.01 μm or more and 0.12 μm or less. A heat treatment comprising: an image forming layer containing silver halide; and at least one compound represented by the following formula (A) and at least one nucleating agent on the side having the image forming layer. A developed photosensitive material is provided.

[0008]

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[In the formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom; a halogen atom; Represents a group. X ¹ and X ² each independently represent a hydrogen atom; a halogen atom; or a substituent bonded to a benzene ring by a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom or a phosphorus atom. However, at least one of X ¹ and X ² is a group represented by —NR ⁴ R ⁵ . R ⁴ and R ⁵ each independently represent a hydrogen atom, an alkyl group, an alkenyl group,
Alkynyl group, aryl group, or -C (= O) -R
^{6, -C (= O) -C} (= O) -R 6, -SO 2 -R 6, -
^{SO-R 6, -P (=} O) - is a group represented by (R ⁶⁾ -R ^7. R ⁶ and R ⁷ are each independently a group selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an amino group, a hydroxy group, an alkoxy group, an aryloxy group and a heterocyclic oxy group. is there.
These substituents may be bonded to each other to form a ring. ]

In the present invention, the photosensitive silver halide is preferably formed in advance and chemically sensitized with a chemical sensitizer. In this case, the chemical sensitizer is more preferably a sulfur sensitizer represented by the following general formula (S).

[0011]

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[In the formula (S), R ^{11 to} R ¹⁴ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted A substituted aryl group, a nitrogen-containing heterocyclic group, and an acyl group. R ¹¹ and R ¹² ,
R ¹³ and R ¹⁴ , R ¹¹ and R ¹³ or R ¹² and R ¹⁴ may combine with each other to form a 5-, 6- or 7-membered ring containing a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom. . ]

In the present invention, a substituted alkene derivative represented by the following formula (1) is preferably used as a nucleating agent:
Or at least one compound selected from the acetal compounds represented by the following formula (3).

[0014]

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[In the formula (1), R ²¹ , R ²² and R ²³ are
Each independently represents a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ²¹ and Z, R ²² and R ²³ , R ²¹ and R ²² , and R ²³ and Z may be bonded to each other to form a cyclic structure. In the formula (2), R ²⁴ represents a substituent. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent;
Are each independently an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group,
Represents an anilino group, a heterocyclic oxy group, a heterocyclic thio group or a heterocyclic amino group. In the formula (3), X and Y, and A and B may be bonded to each other to form a cyclic structure. ]

In the present invention, preferably, 50% by weight of the binder of the image forming layer containing photosensitive silver halide is used.
As the above, a polymer latex having a glass transition temperature of −30 ° C. or more and 40 ° C. or less is used.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments and methods of the photothermographic material of the present invention will be described in detail. The photothermographic material of the present invention has a non-photosensitive silver salt, a photosensitive silver halide and a binder on a support, and the number average grain of the photosensitive silver halide is controlled within a specific range. And a nucleating agent and a phenol derivative represented by the formula (A).

The number-average grain size of the photosensitive silver halide used in the present invention is from 0.01 μm to 0.12 μm, preferably from 0.02 μm to 0.10 μm, more preferably from 0.06 μm to 0 μm. .10 μm or less. Number average particle size is the upper limit of 0.12μ
If it is larger than m, the photographic performance after storage is adversely affected, which is not preferable, and the lower limit is 0.01 μm
Is from a manufacturing technology point of view. The number average grain size of the photosensitive silver halide prepared can be adjusted by selecting the grain formation temperature. In general,
The lower the grain formation temperature, the smaller the number average grain size of the photosensitive silver halide prepared. For example, in the following examples, photosensitive silver halide having a number average grain size of 0.16 μm to 0.06 μm was prepared by preparing at a grain formation temperature of 65 ° C. to 30 ° C.
When the silver halide grains are cubic or octahedral so-called normal crystals, the number average grain size referred to here is the sum of grain sizes for the number of grains, with the length of the edge of the silver halide grains as the grain size. Divided by the number of particles.
When the silver halide grains are tabular grains, the diameter calculated as a circular image having the same area as the projected area of the main surface is calculated as the grain size. If other than normal crystal,
For example, in the case of a spherical particle, a rod-like particle, or the like, the diameter of a sphere equivalent to the volume of a silver halide particle is calculated as the particle size. Dmin is determined by the silver halide content in the image forming layer.
max is high and Dmin is low. This is because when the amount of silver is the same, the smaller the particle size, the larger the number of particles and the higher the thermal development activity.

The shape of the silver halide grains is cubic,
Octahedral, tabular particles, spherical particles, rod-like particles, potato-like particles and the like can be mentioned. In the present invention, cubic particles and tabular particles are particularly preferable. When tabular silver halide grains are used, the average aspect ratio is preferably 100: 1 to 2: 1, more preferably 50: 1 to 3: 1. Further, grains having rounded corners of silver halide grains can also be preferably used. The surface index (mirror index) of the outer surface of the photosensitive silver halide grain is not particularly limited, but the spectral sensitization efficiency when the spectral sensitizing dye is adsorbed is high.
The proportion occupied by the [100] plane is preferably high. The ratio is preferably 50% or more, more preferably 65% or more,
80% or more is more preferable. The Miller index [100] plane ratio was determined by T. Tani; J. Imaging Sci., 29, 165 (1985), which utilizes the adsorption dependence of [111] and [100] planes on the adsorption of sensitizing dyes. It can be determined by the method described.

Methods for forming photosensitive silver halide are well known in the art, for example, Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458.
Can be used.Specifically, a photosensitive silver halide is prepared by adding a silver-supplying compound and a halogen-supplying compound to gelatin or another polymer solution, and then the organic silver halide is added. A method of mixing with a silver salt is used. In order to obtain good photographic performance, the photosensitive silver halide is not prepared by a method of converting a part of the organic silver salt to the photosensitive silver salt, but may be formed in advance. preferable. Therefore, in the image forming layer according to a preferred embodiment of the present invention, it is preferable to form the image forming layer by mixing a photosensitive silver halide formed in advance and an organic silver salt.

The photosensitive silver halide grains used in the present invention preferably contain a metal or a metal complex of Group VIII of the periodic table. Rhodium, ruthenium, osmium and iridium are preferred as the metal of Group VIII of the periodic table or the central metal of the metal complex. One kind of these metal complexes may be used, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol per mol of silver,
A range of 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol is more preferable. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used.

As the rhodium compound used in the present invention, a water-soluble rhodium compound can be used. For example, a rhodium (III) halide compound or a rhodium complex salt having a ligand such as halogen, amines, oxalato, etc., for example, hexachlororhodium (II)
I) Complex salts, pentachloroacolodium (III) complex salts, tetrachlorodiachodium (III) complex salts, hexabromorhodium (III) complex salts, hexaamminerhodium (III) complex salts, trioxalathrodium (III) complex salts, and the like. Can be These rhodium compounds are used by dissolving them in water or a suitable solvent. A method generally used for stabilizing a solution of the rhodium compound is generally used, that is, an aqueous solution of hydrogen halide (eg, hydrochloric acid, hydrobromic acid, hydrofluoric acid) Etc.) or alkali halides (eg KCl, NaC
l, KBr, NaBr, etc.) can be used. Instead of using water-soluble rhodium, it is also possible to add and dissolve other silver halide grains doped with rhodium during the preparation of silver halide.

The addition amount of these rhodium compounds is
1 × 10 per mole of silver halide^-8Mol to 5 × 10^-FourMolar range
Enclosure is preferable, and particularly preferably 5 × 10^-8Mol ~ 1 x 1
0^-Five Is a mole. The addition of these compounds
During the production of silver emulsion grains and before each step of coating the emulsion
Can be carried out as needed, but especially during emulsion formation.
And preferably incorporated into silver halide grains.
No.

Ruthenium and Osmiu used in the present invention
No. JP-A-63-2042, JP-A-1-285941, JP-A-2-20852,
It is added in the form of a water-soluble complex salt described in
You. Particularly preferred is a hexagonal compound represented by the following formula:
Position complex. [ML₆]^n- Where M is Ru
Represents Os, L represents a ligand, and n represents 0, 1, 2, 3
Or represents 4. In this case, the counterion is important
Without ammonium or alkali metal ions
It is. A preferable ligand is halide coordination.
Ligand, cyanide ligand, cyanide ligand, nitrosi
And thionitrosyl ligands. Less than
Examples of specific complexes used in the present invention are shown in
Is not limited to this.

[RuCl₆]^3- [RuCl_Four(H_TwoO)_Two]^- [RuCl_Five(H_TwoO)]^2-  [RuCl_Five(NO)]^2- [RuBr_Five(NS)]^2-  [Ru (CO)_ThreeCl_Three]^2- [Ru (CO) Cl_Five]^2- [Ru (CO) Br_Five]^2-  [OsCl₆]^3- [OsCl_Five(NO)]^2- [Os (NO) (CN)_Five]^2-  [Os (NS) Br_Five]^2- [Os (O)_Two(CN)_Four]^Four-

The addition amount of these compounds is 1
The range is preferably from 1 × 10 ^-9 mol to 1 × 10 ^-4 mol, and particularly preferably from 1 × 10 ^-8 mol to 1 × 10 ^-5 mol, per mol. These compounds can be appropriately added at the time of the production of silver halide emulsion grains and at each stage before coating the emulsion, but it is particularly preferable to add them at the time of emulsion formation and incorporate them into the silver halide grains. . In order to add these compounds during silver halide grain formation and to incorporate them into silver halide grains, powder of metal complex or
A method in which an aqueous solution dissolved together with NaCl and KCl is added to a water-soluble salt or water-soluble halide solution during particle formation, or as a third solution when a silver salt and a halide solution are simultaneously mixed. And a method in which silver halide grains are prepared by a simultaneous three-liquid mixing method, or a method in which a required amount of an aqueous solution of a metal complex is charged into a reaction vessel during grain formation. In particular, a method of adding a powder or an aqueous solution dissolved together with NaCl and KCl to a water-soluble halide solution is preferable. In order to add the metal complex to the surface of the particles, a required amount of an aqueous solution of a metal complex can be charged into the reaction vessel immediately after the formation of the particles, during or during the physical ripening, or at the time of chemical ripening.

As the iridium compound used in the present invention, various compounds can be used, and examples thereof include hexachloroiridium, hexaammineiridium, trioxalatoiridium, hexacyanoiridium, and pentachloronitrosyliridium. These iridium compounds are used after being dissolved in water or a suitable solvent. However, a method generally used for stabilizing a solution of the iridium compound, that is, an aqueous solution of hydrogen halide (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) is used. Etc.) or a method of adding an alkali halide (eg, KCl, NaCl, KBr, NaBr, etc.). Instead of using water-soluble iridium, it is also possible to add and dissolve another iridium-doped silver halide grain during silver halide preparation.

Further, the silver halide grains used in the present invention may contain metal atoms such as cobalt, iron, rhenium, nickel, chromium, palladium, platinum, gold, thallium, copper and lead. As the compound of cobalt, iron and chromium, a hexacyano metal complex can be preferably used. Specific examples include, but are not limited to, ferricyanate, ferrocyanate, hexacyanocobaltate, hexacyanochromate, and hexacyanoruthenate. The phase containing the metal complex in the silver halide may be uniform, may be contained at a high concentration in the core portion, or may be contained at a high concentration in the shell portion, and there is no particular limitation. The amount of the metal is preferably 1 × 10 ^-9 to 1 × 10 ^-4 mol per mol of silver halide. In addition, to contain the above metal, a simple salt,
A metal salt in the form of a double salt or a complex salt can be added at the time of particle preparation. The photosensitive silver halide grains can be desalted by washing with a method known in the art such as a noodle method or a flocculation method, but in the present invention, it may or may not be desalted.

The silver halide emulsion used in the present invention is preferably subjected to chemical sensitization. As the gold sensitizer used for gold sensitization, the oxidation number of gold may be +1 or +3, and gold compounds usually used as gold sensitizers can be used. Representative examples include chloroauric acid, potassium chloroaurate, auric trichloride, potassium auric thiocyanate, potassium iodooleate, tetracyano auric acidide, ammonium aurothiocyanate, pyridyl trichlorogold and the like. The addition amount of the gold sensitizer may vary depending on various conditions, per mol of silver halide 10 ^-7 mol to 10 ^-3 mol or less as a guide, and more preferably 10 ^-6 mol to 5
× 10 ^-4 or less.

The silver halide emulsion used in the present invention is preferably used in combination with gold sensitization and another chemical sensitization. As other chemical sensitization methods, known methods such as a sulfur sensitization method, a selenium sensitization method, a tellurium sensitization method, and a noble metal sensitization method can be used. When used in combination with gold sensitization, for example, sulfur sensitization and gold sensitization, selenium sensitization and gold sensitization, sulfur sensitization and selenium sensitization and gold sensitization, Sulfur sensitization, tellurium sensitization, and gold sensitization, and sulfur sensitization, selenium sensitization, tellurium sensitization, and gold sensitization are preferred. As the selenium sensitizer used in the present invention, a known selenium compound can be used. That is, usually, unstable and / or non-unstable selenium compounds are added and
It is carried out by stirring the emulsion at a high temperature of not less than ℃ for a certain period of time. As an unstable selenium compound, Japanese Patent Publication No. 44-15748
No. 43-13489, JP-A-4-25832, 4-109240, 3-1
Compounds described in 21798 and the like can be used. In particular, it is preferable to use the compounds represented by formulas (VIII) and (IX) in JP-A-4-324855.

The tellurium sensitizer used in the present invention is a compound which forms silver telluride which is presumed to be a sensitizing nucleus on the surface or inside of silver halide grains. The formation rate of silver telluride in a silver halide emulsion is described in JP-A-5-3132.
It can be tested by the method described in No. 84. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides, bis (carbamoyl) tellurides, diacyl tellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, P = Te Compounds having a bond, tellurocarboxylates, Te-organyltellurocarboxylates, di (poly) tellurides, tellurides, tellurols, telluroacetals,
Tellurosulfonates, compounds having a P-Te bond, containing T
e Heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Specifically, U.S. Patent Nos. 1,623,499, 3,320,069, 3,772,031, UK Patent 235,211 and 1,121,496,
No. 1,295,462, No. 1,396,696, Canadian Patent 800,9
No. 58, JP-A-4-204640, JP-A-3-53693, JP-A-3-31598, JP-A-4
-129787, Journal of Chemical Society Chemical Communication (J.Chem.Soc.Che)
m.Commun.) 635 (1980), ibid 1102 (1979), ibid 645 (197
9), Journal of Chemical Society Perkin Transaction (J. Chem. Soc. Perkin. Tran)
s.) 1,2191 (1980), edited by S. Patai, edited by The Chemistry of Organic S.
erenium and Tellunium Compounds), Vol 1 (1986), V
ol 2 (1987). In particular, compounds represented by formulas (II), (III) and (IV) in JP-A-5-313284 are preferred.

The amount of the selenium and tellurium sensitizers used in the present invention, the silver halide grains to be used, but the chemical ripening condition and the like and, generally, per mol of silver halide 10 ^-8 to 10 ^-2 mol, Preferably about 10 ^-7 to 10 ^-3 mol is used. The conditions of the chemical sensitization in the present invention are not particularly limited, but the pH is 5 to 8, the pAg is 6 to 11, preferably 7 to 10, and the temperature is 40 to 95 ° C, preferably 45 to 45 ° C. 85 ° C. In the silver halide emulsion used in the present invention, a cadmium salt, a sulfite, a lead salt, a thallium salt, and the like may coexist in the process of forming silver halide grains or physical ripening.

In the present invention, reduction sensitization can be used. As specific compounds of the reduction sensitization method, in addition to ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like can be used. . Also, when the pH of the emulsion is 7 or more or p
Reduction sensitization can be achieved by aging while keeping Ag at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ion during grain formation. The sulfur sensitization preferably used in the present invention is usually carried out by adding a sulfur sensitizer and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. Known compounds can be used as the sulfur sensitizer, and in addition to the sulfur compounds contained in gelatin, various sulfur compounds,
For example, thiosulfates, thioureas, thiazoles, rhodanines and the like can be used. In particular, a preferred sulfur compound is a thiourea compound represented by the following general formula (S).

[0034]

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In the formula (S), R ^{11 to} R ¹⁴ may be the same or different and each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group (for example, a methyl group, an ethyl group, a cyclohexyl group, a hydroxyethyl group). Group, carboxypentyl group, diethylaminopropyl group, etc.), substituted or unsubstituted alkenyl group (allyl group, etc.), substituted or unsubstituted aralkyl group (benzyl group, etc.), substituted or unsubstituted aryl group (phenyl group, p -A tolyl group,
m-methoxyphenyl group), a nitrogen-containing heterocyclic group (pyridyl group, quinoline group, thiazole group, thiadiazole group, oxazole group, benzothiazole group, benzoxazole group, imidazole group, benzimidazole group,
Triazole group, morpholine group, benzotriazole group, etc.) and acyl group (methoxy group, ethoxy group, benzoyl group, etc.). R ¹¹ and R ¹² , R ¹³ and R ¹⁴ , R ¹¹ and R ¹³ or R ¹² and R ¹⁴ are bonded to each other to form a 5-, 6- or 7-membered ring containing a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom. May be formed. Among the compounds represented by the general formula (S), typical specific examples preferably used in the present invention are shown below.

[0036]

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[0037]

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The amount of the sulfur sensitizer to be added depends on p during chemical ripening.
H, temperature, varies depending on various conditions such as the size of the silver halide grains, per mol of silver halide 10 ^-7 to 1
It is 0 ^-2 mol, more preferably 10 ^-5 to 10 ^-3 mol. The silver halide emulsion used in the present invention includes European special 29
A thiosulfonic acid compound may be added by the method shown in 3,917.

The silver halide emulsion in the photothermographic material of the present invention may be of one kind or two or more kinds (for example, those having different average grain sizes, those having different halogen compositions,
Those having different crystal habits and those having different chemical sensitization conditions) may be used in combination.

The photosensitive silver halide is used in an amount of 0.01 to 0.5 mol of the photosensitive silver halide to 1 mol of the organic silver salt.
Mol or less, preferably 0.02 mol or more and 0.3 mol or less, particularly preferably 0.03 mol or more and 0.25 mol or less.
Regarding the mixing method and the mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide particles and organic silver salt were mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. And the like, or a method of preparing an organic silver salt by mixing photosensitive silver halide prepared at any timing during the preparation of the organic silver salt. There is no particular limitation as long as it appears in.

The photothermographic material of the present invention contains a non-photosensitive silver salt. The organic silver salt that can be used in the present invention is relatively stable to light, but at 80 ° C. in the presence of an exposed photocatalyst (such as a latent image of a photosensitive silver halide) and a reducing agent.
Alternatively, it is a silver salt that forms a silver image when heated to a higher temperature. The organic silver salt can be any organic substance including a source capable of reducing silver ions. Silver salts of organic acids, in particular silver salts of long-chain fatty carboxylic acids (with 10 to 30, preferably 15 to 28 carbon atoms) are preferred. Also preferred are organic or inorganic silver salt complexes in which the ligand has a complex stability constant in the range of 4.0 to 10.0. The silver donor material can preferably make up about 5-70% by weight of the imaging layer. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, and silver palmitate.
Silver maleate, silver fumarate, silver tartrate, silver linoleate,
Silver butyrate and silver camphorate, and mixtures thereof. In the present invention, among the above-mentioned organic acid silver or a mixture of organic acid silver, it is preferable to use silver behenate having a content of 75 mol% or more, more preferably 85 mol% or more. . Here, the content of silver behenate indicates the molar fraction of silver behenate with respect to the organic acid silver used.
As the organic acid silver other than silver behenate contained in the organic acid silver used in the present invention, those mentioned above can be preferably used.

The organic acid silver which is preferably used in the present invention is
Alkali metal salts of organic acids shown above (Na salt, K salt,
It is prepared by reacting silver nitrate with a solution or suspension. The alkali metal salt of an organic acid used in the present invention can be obtained by treating the above organic acid with an alkali. The preparation of the silver organic acid can be carried out batchwise or continuously in any suitable vessel. The stirring in the reaction vessel can be performed by any stirring method depending on the required characteristics of the particles. As a preparation method of the organic acid silver,
A method of slowly or rapidly adding an aqueous solution of silver nitrate to a reaction vessel containing an organic acid alkali metal salt solution or suspension. Either a method of slowly or rapidly adding, or a method of simultaneously adding a previously prepared aqueous solution of silver nitrate and a solution or suspension of an organic acid alkali metal salt into a reaction vessel can be preferably used.

The silver nitrate aqueous solution and the organic acid alkali metal salt solution or suspension may be of any concentration for controlling the particle size of the prepared organic acid silver, and may be added at any addition rate. Can be. The silver nitrate aqueous solution and the organic acid alkali metal salt solution or suspension can be added by a method of adding at a constant addition rate, an accelerated addition method by an arbitrary time function, or a deceleration addition method. Further, it may be added to the liquid surface or may be added to the reaction solution. In the case of a method in which a previously prepared aqueous silver nitrate solution and an organic acid alkali metal salt solution or suspension are simultaneously added to the reaction vessel, either the silver nitrate aqueous solution or the organic acid alkali metal salt solution or suspension is preceded. Although it can be added, it is preferable to add the silver nitrate aqueous solution in advance. The degree of precedence is preferably 0 to 50 vol% of the total amount added, and 0 to 2 vol%.
5 vol% is particularly preferred. As described in JP-A-9-127643, a method of adding while controlling the pH or silver potential of the reaction solution during the reaction can also be preferably used.

The pH of the silver nitrate aqueous solution or organic acid alkali metal salt solution or suspension to be added can be adjusted according to the required characteristics of the particles. An optional acid or alkali can be added for pH adjustment. Depending on the required characteristics of the particles, for example, the temperature in the reaction vessel can be set arbitrarily for controlling the particle size of the prepared organic acid silver salt. Alternatively, the suspension can also be adjusted to any temperature. The organic acid alkali metal salt solution or suspension is preferably heated and kept at 50 ° C. or higher in order to ensure fluidity of the solution. The organic acid silver used in the present invention is preferably prepared in the presence of a tertiary alcohol. The tertiary alcohol is preferably one having a total carbon number of 15 or less, and particularly preferably 10 or less. Preferred examples of the tertiary alcohol include tert-butanol, but the present invention is not limited thereto. The tertiary alcohol used in the present invention may be added at any time during the preparation of the organic acid silver salt, but it is preferable to add the tertiary alcohol during the preparation of the organic acid alkali metal salt and dissolve the organic acid alkali metal salt before use. . The amount of the third alcohol can be used freely between 0.01 and 10 by weight ratio to of H ₂ O as a solvent at the time of organic acid silver preparation, the range of 0.03 to 1 is preferred.

The shape of the organic silver salt that can be used in the present invention is not particularly limited, but a needle crystal having a short axis and a long axis is preferable. In the present invention, the minor axis is 0.01 μm or more and 0.2 μm or more.
0 μm or less, major axis of 0.10 μm or more and 5.0 μm or less, minor axis of 0.01 μm or more and 0.15 μm or less, and major axis of 0.10 μm or more and 4.0 μm or less are more preferred. The particle size distribution of the organic silver salt is preferably monodispersed. Monodisperse is the standard deviation of the lengths of the minor and major axes divided by the minor and major axes, respectively.
0 fraction is preferably 80% or less, more preferably 50% or less,
It is more preferably at most 30%. The shape of the organic silver salt can be measured from a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring the monodispersity, there is a method of obtaining the standard deviation of the volume-weighted average diameter of the organic silver salt, the percentage of the value divided by the volume-weighted average diameter (coefficient of variation) is preferably 80% or less, more Preferably 50% or less,
It is more preferably at most 30%. As a measuring method, for example, the particle size (volume weighted average diameter) obtained by irradiating a laser beam to an organic silver salt dispersed in a liquid and obtaining an autocorrelation function with respect to a time change of fluctuation of the scattered light is obtained. Can be. A solid fine particle dispersion having an average particle size of 0.05 μm or more and 10.0 μm or less in this measurement method is preferable. More preferably average particle size 0.1 μm or more and 5.0 μm or less, still more preferably average particle size 0.1 μm
Not less than 2.0 μm.

The organic silver salt that can be used in the present invention is
Preferably, desalting can be performed. The method for desalting is not particularly limited, and a known method can be used. However, a known filtration method such as centrifugal filtration, suction filtration, ultrafiltration, or floc-forming water washing by a coagulation method can be preferably used. In the present invention, for the purpose of obtaining an organic silver salt solid dispersion having a high S / N, a small particle size, and no aggregation, the organic silver salt containing an image forming medium is contained, and the photosensitive silver salt is substantially contained. It is preferable to use a dispersion method in which an aqueous dispersion is converted into a high-speed stream and then the pressure is reduced. After passing through such a process, the mixture is mixed with a photosensitive silver salt aqueous solution to produce a photosensitive image forming medium coating solution. When a photothermographic material is prepared using such a coating solution, a haze is low, and a low-fogging, high-sensitivity photothermographic material can be obtained. On the other hand, when the photosensitive silver salt is coexistent when the light is converted into a high-pressure, high-speed flow and dispersed, the fog increases and the sensitivity is remarkably lowered. When an organic solvent is used instead of water as a dispersion medium, haze increases, fog increases, and sensitivity tends to decrease. On the other hand, when a conversion method for converting a part of the organic silver salt in the dispersion to the photosensitive silver salt is used instead of the method of mixing the aqueous solution of the photosensitive silver salt, the sensitivity is reduced.

In the above, the aqueous dispersion which is dispersed by being converted to high pressure and high speed is substantially free of a photosensitive silver salt, and its content is based on the non-photosensitive organic silver salt. 0.
The content is 1 mol% or less, and the photosensitive silver salt is not positively added. In the present invention, for the solid dispersion apparatus and the technology used to carry out the dispersion method as described above, for example, "dispersion system rheology and dispersion technology"
(Toshio Kajiuchi, Hiroki Usui, 1991, Shinzansha Publishing Co., Ltd.,
p357-p403), "Progress in Chemical Engineering Vol. 24" (incorporated association)
Edited by The Society of Chemical Engineers, Tokai Branch, 1990, Maki Shoten, p184-p18
5), etc., the dispersion method according to the present invention is based on a method in which after a water dispersion containing at least an organic silver salt is pressurized by a high-pressure pump or the like and fed into a pipe, a thin slit provided in the pipe is formed. This is a method in which fine dispersion is performed by causing the dispersion to pass through and then causing a sharp pressure drop in the dispersion. As for the high-pressure homogenizer to which the present invention is related, generally, (a) the dispersoid is released at a normal pressure from a high pressure under a high pressure, and `` shearing force '' generated when the dispersoid passes through a narrow gap at a high speed. It is considered that the particles are dispersed into fine particles by a dispersing force such as “cavitation force” generated when the particles are dispersed. As an example of this type of dispersing apparatus, a Gaulin homogenizer is mentioned in the past.In this apparatus, the liquid to be dispersed sent at a high pressure is converted into a high-speed flow through a narrow gap on a cylindrical surface, and the force is applied to the surrounding wall by the force. The particles collide and are emulsified and dispersed by the impact force. Operating pressure is generally 100~600kg / cm ^2, the number is the flow velocity m~3
It is in the range of 0 m / sec, and in order to increase the dispersion efficiency, a device in which the high flow velocity portion is saw-toothed and the number of collisions is increased has been devised. On the other hand, in recent years, devices capable of dispersing at higher pressure and higher flow rate have been developed,
Typical examples thereof include a microfluidizer (Microfluidex International Corporation) and a nanomizer (Special Kika Kogyo Co., Ltd.).

The dispersion apparatus suitable for carrying out the present invention includes:
Microfluidizer M-110S- manufactured by Microfluidex International Corporation
EH (with G10Z interaction chamber),
M-110Y (with H10Z interaction chamber), M-140K (with G10Z interaction chamber), HC-5000 (L30Z or H2
With 30Z interaction chamber), HC-8
000 (with an E230Z or L30Z interaction chamber) and the like. Using these devices, an aqueous dispersion containing at least an organic silver salt is pressurized by a high-pressure pump or the like and fed into a pipe, and then a desired pressure is applied by passing through a narrow slit provided in the pipe. After that, a sudden pressure drop is caused in the dispersion by, for example, rapidly returning the pressure in the pipe to the atmospheric pressure, whereby an organic silver salt dispersion optimal for the present invention can be obtained.

It is preferable that the raw material liquid is preliminarily dispersed before the dispersion operation. As means for preliminary dispersion, known dispersion means (e.g., high-speed mixer, homogenizer, high-speed impact mill, Banbury mixer, homomixer, kneader, ball mill, vibration ball mill, planetary ball mill, attritor, sand mill, bead mill, colloid mill,
Jet mill, roller mill, tron mill, high-speed stone mill) can be used. Instead of mechanically dispersing, fine particles may be formed by coarsely dispersing in a solvent by controlling the pH and then changing the pH in the presence of a dispersing agent. At this time, an organic solvent may be used as a solvent used for the coarse dispersion, and the organic solvent is usually removed after the completion of the fine particle formation.

In the dispersion of an organic silver salt, it is possible to disperse the particles in a desired particle size by adjusting the flow rate, the differential pressure at the time of pressure drop, and the number of times of processing. / Sec to 600m / sec, differential pressure at pressure drop
Is preferably in the range of 900~3000kg / cm ^2, the flow rate is 300 meters / sec to 60
More preferably, the pressure difference at the time of 0 m / sec and the pressure drop is in the range of 1500 to 3000 kg / cm ² . The number of times of dispersion processing can be selected as needed, but usually 1 to 10 times is selected, but from the viewpoint of productivity, about 1 to 3 times is selected. Heating such aqueous dispersions under high pressure is
At a high temperature exceeding 90 ° C., the particle size tends to increase and fog tends to increase. Therefore, in the present invention, the step before the conversion to the high pressure and high flow rate, the step after the pressure is reduced, or both of these steps include a cooling step, and the temperature of such water dispersion is reduced by the cooling step.
The temperature is preferably maintained in the range of 90 to 90 ° C, more preferably in the range of 5 to 80 ° C, particularly preferably in the range of 5 to 65 ° C. In particular, it is effective to provide the above cooling step at the time of high-pressure dispersion in the range of 1500 to 3000 kg / cm ² . As the cooler, a double tube, a double tube using a static mixer, a multi-tube heat exchanger, a coiled tube heat exchanger, or the like can be appropriately selected according to the required heat exchange amount. Further, in order to increase the efficiency of heat exchange, it is sufficient to select a suitable one such as a pipe thickness, a wall thickness and a material in consideration of a working pressure. As the refrigerant used for the cooler, use 20 ° C well water, 5-10 ° C cold water treated with a refrigerator, and, if necessary, -30 ° C ethylene glycol / water refrigerant, etc., based on the heat exchange amount. You can also.

In the dispersion operation, the organic silver salt is preferably dispersed in the presence of an aqueous solvent-soluble dispersant (dispersion aid). Examples of the dispersing agent include polyacrylic acid, a copolymer of acrylic acid, a maleic acid copolymer, a maleic acid monoester copolymer, a synthetic anionic polymer such as an acrylomethylpropanesulfonic acid copolymer, and carboxymethyl. Starch, semi-synthetic anionic polymer such as carboxymethyl cellulose, alginic acid, anionic polymer such as pectic acid, the compound described in JP-A-7-350753,
Alternatively, known anionic, nonionic, cationic surfactants and other known polymers such as polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, hydroxypropylcellulose, and hydroxypropylmethylcellulose, or naturally occurring polymer compounds such as gelatin Can be appropriately selected and used, but polyvinyl alcohols and water-soluble cellulose derivatives are particularly preferred. It is a general method that the dispersing aid is mixed with the organic silver salt powder or the organic silver salt in a wet cake state before dispersion and sent to a disperser as a slurry, but in a state where it is mixed with the organic silver salt in advance. And a heat treatment or a treatment with a solvent may be performed to obtain an organic silver salt powder or a wet cake. The pH may be controlled by a suitable pH adjuster before, during or after dispersion.

In addition to mechanical dispersion, the particles may be coarsely dispersed in a solvent by controlling the pH, and then finely divided by changing the pH in the presence of a dispersing agent. At this time, an organic solvent may be used as a solvent used for the coarse dispersion, and the organic solvent is usually removed after the completion of the fine particle formation. The prepared dispersion is stored with stirring for the purpose of suppressing sedimentation of fine particles during storage, or stored in a highly viscous state by a hydrophilic colloid (for example, in a jelly state using gelatin). You can also. Further, a preservative can be added for the purpose of preventing the propagation of various bacteria during storage.

The organic silver salt solid fine particle dispersion used in the present invention comprises at least an organic silver salt and water. The ratio of the organic silver salt to water is not particularly limited, but the ratio of the organic silver salt to the whole is preferably 5 to 50% by weight, and more preferably 10 to 30% by weight.
It is preferable to use the above-mentioned dispersing aid, but it is preferable to use the dispersing aid in a minimum amount within a range suitable for minimizing the particle size, and 0.5 to 30% by weight, especially 1 to 30% by weight based on the organic silver salt.
A range of 15% by weight is preferred. In the present invention, it is possible to produce a photosensitive material by mixing the organic silver salt aqueous dispersion and the photosensitive silver salt aqueous dispersion, the mixing ratio of the organic silver salt and the photosensitive silver salt can be selected according to the purpose, The ratio of the photosensitive silver salt to the organic silver salt is preferably in the range of 1 to 30 mol%, more preferably 3 to 2 mol%.
A range of 0 mol%, especially 5 to 15 mol% is preferred. Mixing two or more aqueous dispersions of organic silver salts with two or more aqueous dispersions of photosensitive silver salts during mixing is a method preferably used for adjusting photographic characteristics. In the present invention, the organic silver salt can be used in a desired amount, but the silver amount is 0.1 to 5 g /
m ² is preferred, and more preferably 1-3 g / m ² .

In the present invention, it is preferable to add a metal ion selected from Ca, Mg, Zn and Ag to the non-photosensitive organic silver salt. Regarding the addition of a metal ion selected from Ca, Mg, Zn and Ag to the non-photosensitive organic silver salt, it is preferable to add it in the form of a non-halide, water-soluble metal salt, specifically, nitrate or sulfuric acid. It is preferably added in the form of a salt or the like. Addition of halides can be used to preserve the image of the processed photosensitive material due to light (such as room light or sunlight),
This is not preferable because it deteriorates the so-called printout property. For this reason, in the present invention, it is not the above-mentioned halide,
It is preferably added in the form of a water-soluble metal salt. The addition time of the metal ion selected from Ca, Mg, Zn and Ag preferably used in the present invention is, for example, after the particle formation of the non-photosensitive organic silver salt, immediately before the particle formation, before the dispersion, after the dispersion and before and after the preparation of the coating solution. The timing may be any time as long as immediately before the coating, preferably after the dispersion and before and after the preparation of the coating solution. The addition amount of the metal ion selected from Ca, Mg, Zn and Ag in the present invention is preferably 10 ^-3 to 10 ^-1 mol per mol of non-photosensitive organic silver, and particularly preferably 5 × 10 ^{-3 to} 5 × 10 ³ mol. ^-2 mol is preferred.

The photothermographic material of the present invention contains at least one compound represented by the following formula (A). Hereinafter, the compound represented by the formula (A) will be described in detail.

[0056]

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In the formula, R ¹ , R ² and R ³ each independently represent a hydrogen atom; a halogen atom; or a substituent bonded to a benzene ring by a carbon atom, oxygen atom, nitrogen atom, sulfur atom or phosphorus atom. Examples of the substituent bonded to the benzene ring at a carbon atom include a linear, branched or cyclic alkyl group, alkenyl group, alkynyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, cyano group , A carboxyl group, a heterocyclic group, a sulfonylcarbamoyl group, an acylcarbamoyl group, a sulfamoylcarbamoyl group, a carbazoyl group,
Examples include an oxalyl group, an oxamoyl group, and a thiocarbamoyl group. Examples of the substituent bonded to the benzene ring with an oxygen atom include a hydroxy group, an alkoxy group, an aryloxy group,
Examples include a heterocyclic oxy group, an acyloxy group, an (alkoxy or aryloxy) carbonyloxy group, a carbamoyloxy group, and a sulfonyloxy group.

Examples of the substituent bonded to the benzene ring at the nitrogen atom include amino, nitro, hydrazino, heterocyclic, acylamino, (alkoxy or aryloxy) carbonylamino, sulfonamide, and sulfamoyl. Amino group, semicarbazide group, thiosemicarbazide group, hydrazino group, quaternary ammonio group, oxamoylamino group, ureido group, thioureido group, (alkyl or aryl) sulfonyluleide group, acylureido group, acylsulfamoylamino group, phosphoryl Amino group, imide group and the like. Examples of the substituent bonded to the benzene ring with a sulfur atom include a mercapto group, a disulfide group, a sulfo group, a sulfino group, a sulfonylthio group, a thiosulfonyl group, an alkylthio group, an arylthio group, a sulfonyl group, a sulfinyl group, a sulfamoyl group, and an acyl group. A sulfamoyl group, a sulfonylsulfamoyl group, a sulfo group, a heterocyclic thio group and the like. Examples of the substituent bonded to the benzene ring with a phosphorus atom include a phosphonyl group and a phosphinyl group. These substituents may be further substituted with these substituents.

X ¹ and X ² each independently represent a hydrogen atom; a halogen atom; or a substituent bonded to a benzene ring by a carbon atom, oxygen atom, nitrogen atom, sulfur atom or phosphorus atom. When X ¹ and X ² represent a substituent other than a hydrogen atom and a halogen atom, specific examples are selected from the same range as when R ¹ , R ² and R ³ represent a substituent. However, at least one of X ¹ and X ² is a group represented by —NR ⁴ R ⁵ . R ⁴ ,
R ⁵ is each independently a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or —C (＝ O)
—R ⁶ , —C (＝ O) —C (＝ O) —R ⁶ , —SO ₂ —
R ⁶ , —SO—R ⁶ , or —P (＝ O) (— R ⁶ ) —
It is a group represented by R ⁷ . R ⁶ and R ⁷ are each independently a group selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an amino group, a hydroxy group, an alkoxy group, and an aryloxy group. These substituents may be bonded to each other to form a ring.

Next, the preferred range of the compound represented by the formula (A) will be described. R ¹ , R ² and R ³ are preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms (eg, methyl, ethyl, propyl, iso- Propyl, tert-
Butyl, n-octyl, tert-amyl, 1,3-tetramethylbutyl, cyclohexyl, trifluoromethyl, difluoromethyl), an alkenyl group having 1 to 20 carbon atoms (eg, vinyl, allyl, 2-butenyl, 3-pentenyl) ), An alkynyl group having 1 to 20 carbon atoms (for example, propargyl,
3-pentynyl), an aryl group having 6 to 20 carbon atoms (eg, phenyl, p-methylphenyl, naphthyl), an acyl group having 1 to 20 carbon atoms (eg, acetyl, benzoyl,
Formyl, pivaloyl), an alkoxycarbonyl group having 2 to 20 carbon atoms (for example, methoxycarbonyl, ethoxycarbonyl), an aryloxycarbonyl group having 7 to 20 carbon atoms (for example, phenoxycarbonyl),
20 carbamoyl groups (eg, carbamoyl, diethylcarbamoyl, phenylcarbamoyl), a cyano group,
Carboxyl group, heterocyclic group having 1 to 20 carbon atoms (eg, 1-imidazolyl, morpholinyl, 3-pyrazolyl), hydroxy group, alkoxy group having 1 to 20 carbon atoms (eg,
Methoxy, ethoxy, butoxy), an aryloxy group having 6 to 20 carbon atoms (eg, phenyloxy, 2-naphthyloxy), a heterocyclic oxy group having 1 to 20 carbon atoms (eg, 4-pyridyloxy), and 2 carbon atoms To 20 acyloxy groups (eg, acetoxy, benzoyloxy), an amino group having 0 to 20 carbon atoms (eg, amino, methylamino, dimethylamino, diethylamino, dibenzylamino), a nitro group, an acylamino having 1 to 20 carbon atoms Groups (eg, acetylamino, benzoylamino), 2 carbon atoms
To 20 alkoxycarbonylamino groups (for example, methoxycarbonylamino), 7 to 20 carbon atoms of an aryloxycarbonylamino group (for example, phenyloxycarbonylamino), and 1 to 20 carbon atoms of a sulfonamide group (for example, methanesulfonamide) Benzenesulfonamide), a sulfamoylamino group having 1 to 20 carbon atoms, a sulfamoyl group having 0 to 20 carbon atoms (for example, sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, phenylsulfamoyl), and 0 carbon atoms -20 ureido groups (e.g., ureido, methylureide, phenylureide), imide groups having 2 to 20 carbon atoms (e.g., succinimide, phthalimide, trifluoromethanesulfonimide), mercapto groups, disulfide groups having 1 to 20 carbon atoms, Sulfo group, Fino group, alkylthio group having 1 to 20 carbon atoms (eg, methylthio, ethylthio), arylthio group having 6 to 20 carbon atoms (eg, phenylthio), sulfonyl group having 1 to 20 carbon atoms (eg, mesyl, tosyl, phenylsulfonyl) ), A sulfinyl group having 1 to 20 carbon atoms (eg, methanesulfinyl, benzenesulfinyl), a heterocyclic thio group having 1 to 20 carbon atoms (eg, 2-imidazolylthio), a phosphinyl group having 1 to 20 carbon atoms (eg, Diethoxyphosphinyl group, diphenylphosphinyl), and a phosphorylamino group having 1 to 20 carbon atoms (eg, diethylphosphorylamino).

R ¹ , R ² and R ³ are more preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxy group. Carbonyl group,
Cyano group, carboxyl group, carbamoyl group, heterocyclic group, hydroxy group, alkoxy group, aryloxy group,
An acyloxy group, an amino group, a nitro group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonamide group, an imide group, a mercapto group, a sulfo group, an alkylthio group, an arylthio group, a sulfonyl group, and a sulfamoyl group. R ¹ ,
More preferred R ² and R ³ are a hydrogen atom, a halogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, cyano group, Carboxyl group, carbamoyl group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, nitro group, acylamino group, sulfonamide group, mercapto group, sulfo group, alkylthio group, arylthio group, sulfonyl group, and sulfamoyl group.

Preferred examples of X ¹ and X ² other than the group represented by —NR ⁴ R ⁵ are selected from the same ranges as preferred examples of R ¹ , R ² and R ³ , and more preferred are also the same. Selected from a range. In the group represented by -NR ⁴ R ^5, -C
^{(= O) -R 6, -C} (= O) -C (= O) -R 6, -S
^{_{O 2 -R 6, -SO-R}} 6, -P (= O) (- R 6) -R 7
R ⁴ and R ⁵ other than the group represented by are preferably a hydrogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms (eg, methyl, ethyl,
Propyl, iso-propyl, tert-butyl, n-octyl, t
ert-amyl, 1,3-tetramethylbutyl, cyclohexyl, trifluoromethyl, difluoromethyl), an alkenyl group having 1 to 20 carbon atoms (for example, vinyl, allyl, 2-
Butenyl, 3-pentenyl), an alkynyl group having 1 to 20 carbon atoms (eg, propargyl, 3-pentynyl), and an aryl group having 6 to 20 carbon atoms (eg, phenyl, p-methylphenyl, naphthyl), more preferably. Is a hydrogen atom,
A straight-chain, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, an alkynyl group having 1 to 10 carbon atoms, and an aryl group having 6 to 12 carbon atoms. .

-C (= O) -R ⁶ , -C (= O) -C
^{(= O) -R 6, -SO} 2 -R 6, -SO-R 6, -P (=
O) In the group represented by (—R ⁶ ) —R ⁷ , preferred as R ⁶ and R ⁷ are a hydrogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. (Eg, methyl, ethyl, propyl, iso-propyl, tert-
Butyl, n-octyl, tert-amyl, 1,3-tetramethylbutyl, cyclohexyl, trifluoromethyl, difluoromethyl), an alkenyl group having 1 to 20 carbon atoms (eg, vinyl, allyl, 2-butenyl, 3-pentenyl) ), An alkynyl group having 1 to 20 carbon atoms (for example, propargyl,
3-pentynyl), a C6-C20 aryl group (e.g., phenyl, p-methylphenyl, naphthyl), a hydroxy group, a C1-C20 alkoxy group (e.g., methoxy, ethoxy, butoxy), a C6-carbon To 20 aryloxy groups (for example, phenyloxy, 2-naphthyloxy), and a heterocyclic oxy group having 1 to 20 carbon atoms (for example, 4-
Pyridyloxy), an amino group having 1 to 20 carbon atoms (for example,
Amino, methylamino, dimethylamino, diethylamino, dibenzylamino) and a heterocyclic group having 1 to 20 carbon atoms (eg, 1-imidazolyl, morpholinyl, 3-pyrazolyl). More preferably, a hydrogen atom and a carbon number of 1 to 10
Linear, branched or cyclic, substituted or unsubstituted alkyl group, alkenyl group having 1 to 10 carbon atoms,
0 alkynyl group, aryl group having 6 to 12 carbon atoms, hydroxy group, alkoxy group having 1 to 10 carbon atoms, 6 to carbon atoms
They are a 12 aryloxy group, a C1-C10 heterocyclic oxy group, a C1-C10 amino group, and a C1-C10 heterocyclic group. More preferably, a hydrogen atom and carbon number 1
10 to 10 linear, branched or cyclic, substituted or unsubstituted alkyl groups, C6 to C12 aryl groups, hydroxy groups, C1 to C10 alkoxy groups, C6 to C12
An aryloxy group, an amino group having 1 to 10 carbon atoms, and a heterocyclic group having 1 to 10 carbon atoms.

In the compound represented by the formula (A), R ¹ , R ² and R ³ are more preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group, Acyl group, alkoxycarbonyl group, aryloxycarbonyl group, cyano group, carboxyl group, carbamoyl group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, nitro group, acylamino group, sulfonamide group, mercapto group, sulfo group, An alkylthio group, an arylthio group, a sulfonyl group, or a sulfamoyl group, wherein one of X ¹ and X ² is a hydrogen atom,
Halogen atom, linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, cyano group, carboxyl group, carbamoyl group, hydroxy group,
An alkoxy group, an aryloxy group, an acyloxy group, a nitro group, an acylamino group, a sulfonamide group, a mercapto group, a sulfo group, an alkylthio group, an arylthio group, a sulfonyl group, a sulfamoyl group, and the other is -N
R ⁴ represents R ⁵ , and at least one of R ⁴ and R ⁵ represents —
^{C (= O) -R 6,} -C (= O) -C (= O) -R 6, -
SO ₂ —R ⁶ , —SO—R ⁶ , —P (＝ O) (— R ⁶ ) —R
It is the time of the group represented by ⁷ .

In the compound represented by the formula (A), R ¹ , R ² and R ³ are particularly preferably a hydrogen atom, a halogen atom, a linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group, An acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, a carbamoyl group, a hydroxy group, an acylamino group, a sulfonamide group, a sulfonyl group, and a sulfamoyl group; one of X ¹ and X ² is a hydrogen atom or a halogen Atom, linear, branched or cyclic, substituted or unsubstituted alkyl group, aryl group,
An acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, a carbamoyl group, hydroxy group, an acylamino group, a sulfonamido group, a sulfonyl group, a sulfamoyl group, the other represents -NR ⁴ R ^5, and R ⁴ , the other is -C one is a hydrogen atom of R ^{5
(= O) -R 6, -SO} 2 -R 6, -P (= O) (- R 6)
It is the time of the group represented by —R ⁷ .

These substituents may be further substituted with the substituents described above. Further, as long as these substituents have a highly acidic hydrogen atom, their protons may be dissociated to form a salt. As the counter cation, metal ions, ammonium ions, and phosphonium ions are used. Such a state in which active hydrogen is dissociated can be an effective countermeasure in cases where volatility during development of the compound becomes a problem. When one molecule of the compound represented by the formula (A) has only one phenol structure, the total number of carbon atoms of the substituent is preferably 1 to 200.
, More preferably 1 to 150, and still more preferably 1 to 100. However, this is not the case when a plurality of the phenol structures are bonded to a polymer chain, and those having an average molecular weight of 500,000 or less are used. In addition, compounds such as bis-forms and tris-forms bonded by a linking group having 1 to 100 carbon atoms are also effective. Increasing the molecular weight as described above can be an effective measure in cases where volatility during development of the compound becomes a problem.

The compound represented by the formula (A) used in the present invention may have a built-in adsorptive group that adsorbs to silver halide. Examples of such adsorbing groups include U.S. Pat. Nos. 4,385,108 and 4,459,347 such as alkylthio, arylthio, thiourea, thioamide, mercapto heterocyclic, and triazole groups.
JP-A-59-195233 and JP-A-59-200231.
Nos. 59-201045 and 59-201046
Nos. 59-201047 and 59-201048
No. 59-201049, JP-A-61-17073.
Nos. 3, 61-270744, 62-948, 63-234244, 63-234245, and 6
The group described in 3-234246 is mentioned. These adsorbing groups to silver halide may be precursors. Examples of such a precursor include the groups described in JP-A-2-285344. The compound represented by the formula (A) used in the present invention may be one in which a ballast group or a polymer commonly used in immobile photographic additives such as couplers is incorporated. A ballast group is a group having a carbon number of 8 or more and relatively inert to photographic properties, for example, an alkyl group,
It can be selected from aralkyl groups, alkoxy groups, phenyl groups, alkylphenyl groups, phenoxy groups, alkylphenoxy groups and the like. Examples of the polymer include those described in JP-A-1-100530.

The compound represented by the formula (A) used in the present invention contains a cationic group (specifically, a group containing a quaternary ammonium group, or a group containing a quaternized nitrogen atom). A group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, a (alkyl, aryl, or heterocyclic) thio group, or a dissociable group (carboxy group, sulfo group,
Acylsulfamoyl group, carbamoylsulfamoyl group, etc.). Specific examples of these groups include, for example, JP-A-7-234471 and JP-A-5-3
No. 33466, JP-A-6-19032, JP-A-6-1
No. 9031, JP-A-5-45761, U.S. Pat.
No. 4365, U.S. Pat. No. 4,988,604, JP-A-3-2
59240, JP-A-7-5610, JP-A-7-24
No. 4348, German Patent No. 4006032 and the like. Next, preferred specific examples of the compound represented by the formula (A) are shown below. However, the present invention is not limited to the following compounds.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

[0072]

[Table 4]

[0073]

[Table 5]

[0074]

[Table 6]

[0075]

[Table 7]

The compound represented by the formula (A) can be easily synthesized by a known method.
-80386, JP-A-5-257227, and JP-A-10-221806. The amount of the compound represented by the formula (A) is from 1 × 10 ^-6 mol to 2 × 10 ^-1 mol, preferably 1 × 10 ^-5 mol, per mol of the organic silver salt used.
From 1 × 10 ^-1 mol, more preferably from 5 × 10 ^-4 mol
5 × 10 ^-2 mol. The compound represented by the formula (A) is
Dissolve in water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone), dimethylformamide, dimethyl sulfoxide, methyl cellosolve, etc. Can be. Also, by an already well-known emulsification dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone are dissolved and mechanically emulsified and dispersed. An object can be prepared and used. Alternatively, the powder can be dispersed in water by a ball mill, a colloid mill, a sand grinder mill, a Manton-Gaulin, a microfluidizer, or an ultrasonic wave by a method known as a solid dispersion method.

The compound represented by the formula (A) may be added to the layer on the image forming layer side with respect to the support, that is, the image forming layer or any other layer on this layer side. It is preferably added to a layer adjacent thereto. The compound represented by the formula (A) is preferably used in combination with a reducing agent for reducing an organic silver salt described later. As the reducing agent to be used in combination, a compound (a so-called hindered phenol compound) having only one hydroxyl group on the benzene ring of a phenol compound and having at least one substituent at an ortho position of the hydroxyl group is preferably used. Specific examples are U.S. Pat.No. 5,496,955, JP-A-9-274274, JP-A-9-304876.
And the like. Next, the nucleating agent used in the present invention will be described. Although the type of the nucleating agent used in the present invention is not particularly limited, a substituted alkene derivative, a substituted isoxazole derivative and a specific acetal compound are preferably used, and among them, compounds represented by the following formulas (1) to (3) Is preferred. The substituted alkene derivative represented by the formula (1), the substituted isoxazole derivative represented by the formula (2), and the specific acetal compound represented by the formula (3) which are preferably used in the present invention will be described.

[0078]

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In the formula (1), R^{twenty one}, R^{twenty two}, R^{twenty three}Is it
Each independently represents a hydrogen atom or a substituent, and Z is an electron-withdrawing atom.
Represents a functional group or a silyl group. In the formula (1), R^{twenty one}And Z,
R^{twenty two} And R^{twenty three}, R^{twenty one}And R^{twenty two}Or R^{twenty three}And Z are connected to each other
Together, they may form a ring structure. In equation (2)
R^{twenty four}Represents a substituent. In equation (3), X and Y are each
Each independently represents a hydrogen atom or a substituent, and A and B are each
Independently, an alkoxy group, an alkylthio group, an alkyl group
Mino group, aryloxy group, arylthio group, anilino
Group, heterocyclic oxy group, heterocyclic thio group, or hetero
Represents a ring amino group. In equation (3), X and Y or A
And B may combine with each other to form a cyclic structure
No. The compound represented by the formula (1) will be described in detail.
In the formula (1), R^{twenty one}, R^{twenty two}, R^{twenty three}Are each independently water
Z represents an electron atom or a substituent;
Represents a ril group. In the formula (1), R^{twenty one}And Z, R^{twenty two} And R^{twenty three},
R^{twenty one}And R^{twenty two}Or R^{twenty three}And Z are bonded to each other to form a ring structure.
The structure may be formed. R^{twenty one}, R^{twenty two}, R^{twenty three}Is a substituent
When represented, examples of the substituent include, for example, a halogen atom (F
Atom, chlorine atom, bromine atom or iodine atom),
Alkyl group (aralkyl group, cycloalkyl group, active
Alkenyl, alkynyl, ant
And heterocyclic groups (including N-substituted nitrogen-containing heterocyclic groups).
A) a heterocyclic group containing a quaternized nitrogen atom (eg,
Pyridinio group), acyl group, alkoxycarbonyl group,
Aryloxycarbonyl group, carbamoyl group, carbo
Xy groups or salts thereof, imino groups, imines substituted with N atoms
No group, thiocarbonyl group, sulfonylcarbamoyl group,
Acylcarbamoyl group, sulfamoylcarbamoyl
Group, carbazoyl group, oxalyl group, oxamoyl group,
Cyano group, thiocarbamoyl group, hydroxy group or
Salt, alkoxy group (ethyleneoxy group or propyl group)
Including groups containing repeating renoxy group units), aryl
Oxy group, heterocyclic oxy group, acyloxy group, (Al
A (oxy or aryloxy) carbonyloxy group,
Carbamoyloxy group, sulfonyloxy group, amino
Group, (alkyl, aryl, or heterocycle) amino
Group, acylamino group, sulfonamide group, ureido group,
Thioureido group, imide group, (alkoxy or ant
Oxy) carbonylamino group, sulfamoylamido
Group, semicarbazide group, thiosemicarbazide group, hydride
Radino group, quaternary ammonium group, oxamoylamino
Group, (alkyl or aryl) sulfonyluureido
Group, acylureido group, acylsulfamoylamino
Group, nitro group, mercapto group, (alkyl, aryl,
Or heterocycle) thio, acylthio, (alkyl
Or aryl) sulfonyl group, (alkyl or aryl
B) sulfinyl group, sulfo group or salt thereof, sulfa
Moyl group, acyl sulfamoyl group, sulfonyl sulf
Amoyl group or its salt, phosphoryl group, phosphoric amide
Or a group containing a phosphate ester structure, a silyl group,
And the like. These substituents are those substituents
May be further substituted.

The electron-withdrawing group represented by Z in the formula (1) is a substituent whose Hammett's substituent constant σ _p can take a positive value. Carbonyl group, aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted with an N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, halogen atom,
A perfluoroalkyl group, a perfluoroalkaneamide group, a sulfonamide group, an acyl group, a formyl group, a phosphoryl group, a carboxy group (or a salt thereof), a sulfo group (or a salt thereof), a heterocyclic group, an alkenyl group, an alkynyl group, Examples include an acyloxy group, an acylthio group, a sulfonyloxy group, and an aryl group substituted with these electron-withdrawing groups. Here, the heterocyclic group is a saturated or unsaturated heterocyclic group, for example, a pyridyl group, a quinolyl group,
Examples thereof include a pyrazinyl group, a quinoxalinyl group, a benzotriazolyl group, an imidazolyl group, a benzimidazolyl group, a hydantoin-1-yl group, a succinimide group, and a phthalimide group. The electron-withdrawing group represented by Z in the formula (1) may further have a substituent, and as the substituent, R ²¹ , R ²² and R ^{23 in} the formula (1) represent The same substituents as the substituents which may be present at the time of expression are exemplified. In the formula (1), R ²¹ and Z, R ²² and R ²³ , R
R ²¹ and R ²² or R ²³ and Z may be bonded to each other to form a cyclic structure. The cyclic structure formed at this time is a non-aromatic carbon ring or a non-aromatic hetero ring. It is.

Next, a preferred range of the compound represented by the formula (1) will be described. The silyl group represented by Z in the formula (1) is preferably a trimethylsilyl group, t
-Butyldimethylsilyl group, phenyldimethylsilyl group, triethylsilyl group, triisopropylsilyl group,
And a trimethylsilyldimethylsilyl group. The electron-withdrawing group represented by Z in the formula (1) is preferably a group having a total number of carbon atoms of 0 to 30, that is, a cyano group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a thiocarbonyl group, Imino group, imino group substituted with N atom, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group, acyloxy group, acylthio group, or any electron withdrawing A phenyl group substituted with a functional group, and more preferably,
Cyano group, alkoxycarbonyl group, carbamoyl group,
Imino group, sulfamoyl group, alkylsulfonyl group,
An arylsulfonyl group, an acyl group, a formyl group, a phosphoryl group, a trifluoromethyl group, or a phenyl group substituted with any electron-withdrawing group, and particularly preferably a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group , An imino group or a carbamoyl group. The group represented by Z in the formula (1) is more preferably an electron-withdrawing group.

The substituent represented by R ²¹ , R ²² and R ²³ in the formula (1) is preferably a group having a total carbon number of 0 to 30, specifically, Z in the above formula (1). A group having the same meaning as the electron-withdrawing group represented, and an alkyl group, a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, Heterocyclic thio group, amino group,
Alkylamino group, arylamino group, heterocyclic amino group, ureido group, acylamino group, sulfonamide group,
Or a substituted or unsubstituted aryl group. Further, in the formula (1), R ²¹ is preferably an electron-withdrawing group, an aryl group, an alkylthio group, an alkoxy group, or an acylamino group, a hydrogen atom, or a silyl group. When R ²¹ represents an electron-withdrawing group, preferably the following groups having a total carbon number of 0 to 30, that is, a cyano group, a nitro group, an acyl group, a formyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a thiocarbonyl group , Imino group, N
An atom-substituted imino group, an alkylsulfonyl group, an arylsulfonyl group, a carbamoyl group, a sulfamoyl group, a trifluoromethyl group, a phosphoryl group, a carboxy group (or a salt thereof), or a saturated or unsaturated heterocyclic group; Preferred are a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, a carbamoyl group, an imino group, an imino group substituted with an N atom, a sulfamoyl group, a carboxy group (or a salt thereof), or a saturated or unsaturated heterocyclic group. Particularly preferably, a cyano group,
A formyl group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, or a saturated or unsaturated heterocyclic group. When R ²¹ represents an aryl group, it is preferably a substituted or unsubstituted phenyl group having 6 to 30 carbon atoms,
Examples of the substituent include any substituent, and among them, an electron-withdrawing substituent is preferable. In the formula (1), R
²¹ is more preferably a group representing an electron-withdrawing group or an aryl group.

In the formula (1), the substituents represented by R ²² and R ²³ are preferably specific examples of Z in the above formula (1)
A group having the same meaning as the electron-withdrawing group represented by, an alkyl group, a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, Examples include a heterocyclic thio group, an amino group, an alkylamino group, an anilino group, a heterocyclic amino group, an acylamino group, and a substituted or unsubstituted phenyl group. In the formula (1), R ²² and R ²³ are
More preferably, one of them is a hydrogen atom and the other represents a substituent. Preferably as the substituent,
Alkyl group, hydroxy group (or a salt thereof), mercapto group (or a salt thereof), alkoxy group, aryloxy group,
Heterocyclic oxy group, alkylthio group, arylthio group,
A heterocyclic thio group, an amino group, an alkylamino group, an anilino group, a heterocyclic amino group, an acylamino group (particularly a perfluoroalkaneamide group), a sulfonamide group, a substituted or unsubstituted phenyl group, or a heterocyclic group; More preferably a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group, Particularly preferred are a hydroxy group (or a salt thereof), an alkoxy group, and a heterocyclic group.

In the formula (1), Z and R ²¹ , or alternatively, R ²²
It is also preferred that and R ²³ form a cyclic structure. The cyclic structure formed in this case is a non-aromatic carbocyclic ring or a non-aromatic hetero ring, preferably a 5- to 7-membered cyclic structure having a total carbon number including a substituent of 1 to 4
0, more preferably 3 to 30. Among the compounds represented by the formula (1), one of the more preferable ones is that Z is a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group,
Represents an imino group or a carbamoyl group, R ²¹ represents an electron-withdrawing group or an aryl group, one of R ^{22 and} R ²³ is a hydrogen atom, and the other is a hydroxy group (or a salt thereof), a mercapto group (or Salt), an alkoxy group,
The compound represents an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group. Further, one of the particularly preferable compounds represented by the general formula (1) is that Z and R ^{21 form a} non-aromatic 5- to 7-membered cyclic structure,
Either ²² or R ²³ is a hydrogen atom, and the other is a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, A compound representing a ring thio group or a heterocyclic group. At this time, R
^As Z which forms a non-aromatic cyclic structure together with ²¹ , an acyl group, a carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group and the like are preferable, and R ¹ is an acyl group, a carbamoyl group, an oxycarbonyl group. And a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted with an N atom, an acylamino group, and a carbonylthio group.

Next, the compound represented by the formula (2) will be described. In the formula (2), R ²⁴ represents a substituent. As the substituent represented by R ²⁴ , the same substituents as described for the substituents of R ^{21 to} R ^{23 in} the formula (1) can be mentioned. The substituent represented by R ²⁴ is preferably an electron-withdrawing group or an aryl group. When R ²⁴ represents an electron-withdrawing group, preferably
The following groups having a total carbon number of 0 to 30, that is, a cyano group, a nitro group, an acyl group, a formyl group, an alkoxycarbonyl group,
Aryloxycarbonyl group, alkylsulfonyl group,
Arylsulfonyl group, carbamoyl group, sulfamoyl group, trifluoromethyl group, phosphoryl group, imino group, or a saturated or unsaturated heterocyclic group, further cyano group, acyl group, formyl group, alkoxycarbonyl group, carbamoyl group, Sulfamoyl, alkylsulfonyl, arylsulfonyl, and heterocyclic groups are preferred. Particularly preferred are a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, and a heterocyclic group. When R ²⁴ represents an aryl group, preferably a total carbon number of 0 to 30, a substituted or unsubstituted phenyl group, the substituent, R ^21, R ²² of formula (1),
When R ²³ represents a substituent, the same as those described as the substituent can be mentioned. R ⁴ is particularly preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, a heterocyclic group, or a substituted or unsubstituted phenyl group, and most preferably a cyano group, a heterocyclic group, or an alkoxycarbonyl group.

Next, the compound represented by the formula (3) will be described in detail. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent:
Represents an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group. X and Y or A and B may be bonded to each other to form a cyclic structure. As the substituents represented by X and Y in the formula (3), the same substituents as described for the substituents R ^{21 to} R ^{23 in} the formula (1) can be mentioned. Specifically, alkyl groups (including perfluoroalkyl groups, trichloromethyl groups, etc.), aryl groups, heterocyclic groups, halogen atoms, cyano groups, nitro groups, alkenyl groups, alkynyl groups, acyl groups, formyl groups, alkoxy groups Carbonyl group, aryloxycarbonyl group, imino group, imino group substituted with an N atom, carbamoyl group, thiocarbonyl group, acyloxy group, acylthio group, acylamino group,
Alkylsulfonyl, arylsulfonyl, sulfamoyl, phosphoryl, carboxy (or salt thereof), sulfo (or salt thereof), hydroxy (or salt thereof), mercapto (or salt thereof), alkoxy, aryl Oxy group, heterocyclic oxy group, alkylthio group, arylthio group, heterocyclic thio group, amino group,
Examples thereof include an alkylamino group, an anilino group, a heterocyclic amino group, and a silyl group. These groups may further have a substituent. X and Y may be bonded to each other to form a cyclic structure, and the cyclic structure formed in this case may be a non-aromatic carbon ring or a non-aromatic hetero ring. .

The substituents represented by X and Y in the formula (3) are preferably groups having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and include a cyano group, an alkoxycarbonyl group, Aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted with N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group , An acylamino group, an acyloxy group, an acylthio group, a heterocyclic group, an alkylthio group, an alkoxy group, or an aryl group. In the formula (3), X and Y are more preferably cyano group, nitro group, alkoxycarbonyl group, carbamoyl group, acyl group, formyl group, acylthio group, acylamino group, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, aryl Sulfonyl group, imino group,
An imino group, a phosphoryl group, a trifluoromethyl group, a heterocyclic group, or a substituted phenyl group substituted with an N atom, particularly preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, an alkylsulfonyl group, an arylsulfonyl group , Acyl group, acylthio group, acylamino group, thiocarbonyl group, formyl group, imino group, N
Examples include an imino group substituted with an atom, a heterocyclic group, and a phenyl group substituted with an arbitrary electron-withdrawing group. X and Y
Are preferably bonded to each other to form a non-aromatic carbon ring or a non-aromatic hetero ring. At this time, the ring structure formed is preferably a 5- to 7-membered ring, and the total carbon number is preferably 1 to 40, and more preferably 3 to 30.
X and Y forming a cyclic structure are preferably an acyl group, a carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted by an N atom, an acylamino group, a carbonylthio group, and the like.

In the formula (3), A and B are each independently:
Represents an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group, which are bonded to each other to form a cyclic structure. You may. In the formula (3), the groups represented by A and B preferably have a total carbon number of 1 to 40, more preferably a total carbon number of 1 to 40.
To 30 and may further have a substituent.
In the formula (3), A and B more preferably combine with each other to form a cyclic structure. The cyclic structure formed at this time is preferably a 5- to 7-membered non-aromatic hetero ring, and preferably has a total carbon number of 1 to 40, and more preferably 3 to 30. In this case, an example in which A and B are linked (-AB
-), For example, -O- (CH ₂ ) ₂ -O-, -O- (CH ₂ ) ₃ -O-,-
S- (CH ₂ ) ₂ -S-, -S- (CH ₂ ) ₃ -S-, -S-ph-S-, -N (CH ₃ )-(CH ₂ )
₂ -O-, -N (CH ₃ )-(CH ₂ ) ₂ -S-, -O- (CH ₂ ) ₂ -S-, -O- (CH ₂ ) ₃ -S
-, -N (CH ₃ ) -ph-O-, -N (CH ₃ ) -ph-S-, -N (ph)-(CH ₂ ) ₂ -S-
And so on.

The compounds represented by the formulas (1) to (3) used in the present invention may have incorporated therein an adsorptive group that adsorbs to silver halide. Examples of such an adsorbing group include U.S. Pat. Nos. 4,385,108 and 4,459,347 such as an alkylthio group, an arylthio group, a thiourea group, a thioamide group, a mercapto heterocyclic group and a triazole group.
And JP-A-59-195233 and JP-A-59-20023.
No. 1, No. 59-201045, No. 59-201046
Nos. 59-201047 and 59-201048
No. 59-201049, JP-A-61-17073.
Nos. 3, 61-270744, 62-948, 63-234244, 63-234245, and 6
Groups described in JP-A-3-234246. These adsorbing groups to silver halide may be precursors. Examples of such a precursor include the groups described in JP-A-2-285344. The compounds represented by the formulas (1) to (3) used in the present invention may have incorporated therein a ballast group or a polymer commonly used in immobile photographic additives such as couplers. Particularly, those incorporating a ballast group are one of preferred examples of the present invention. The ballast group has a carbon number of 8 or more and is relatively inert to photographic properties, such as an alkyl group, an aralkyl group, an alkoxy group,
It can be selected from a phenyl group, an alkylphenyl group, a phenoxy group, an alkylphenoxy group and the like. Examples of the polymer include those described in JP-A-1-100530.

The compounds represented by the formulas (1) to (3) used in the present invention contain a cationic group (specifically, a group containing a quaternary ammonium group or a quaternized group). A nitrogen-containing heterocyclic group containing a nitrogen atom), a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, an (alkyl, aryl, or heterocyclic) thio group, or a dissociable group (carboxy group) dissociable by a base , A sulfo group,
Acylsulfamoyl group, carbamoylsulfamoyl group, etc.). Particularly, a group containing a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group or a group containing an (alkyl, aryl, or heterocyclic) thio group is one of preferred examples of the present invention. Specific examples of these groups include, for example, JP-A-7-2
No. 34471, JP-A-5-333466, JP-A-6-633
19032, JP-A-6-19031, JP-A-5-4
No. 5761, U.S. Pat. No. 4,994,365, U.S. Pat.
88604, JP-A-3-259240, JP-A-7-
No. 5610, JP-A-7-244348, German Patent 40
06032 and the like. Next, specific examples of the compounds represented by the formulas (1) to (3) used in the present invention are shown below. However, the present invention is not limited to the following compounds.

[0091]

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[0092]

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[0093]

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[0094]

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The compounds represented by the formulas (1) to (3) used in the present invention may be water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol) and ketones (acetone, acetone). Methylethylketone), dimethylformamide, dimethylsulfoxide,
It can be used by dissolving it in methylcellosolve or the like.

Further, by a well-known emulsification and dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, or an auxiliary solvent such as ethyl acetate or cyclohexanone is used to dissolve the compound. An emulsified dispersion can be prepared and used. Alternatively, a compound powder can be dispersed in a suitable solvent such as water by a ball mill, a colloid mill, or ultrasonic waves by a method known as a solid dispersion method and used.

The compounds represented by the formulas (1) to (3) may be added to the layer on the image forming layer side with respect to the support, that is, to the image forming layer or any other layer. It is preferably added to a layer or a layer adjacent thereto. Formula (1)-Formula
The amount of the compound represented by (3) is 1 × with respect to 1 mol of silver.
It is preferably from 10 ^-6 to 1 mol, more preferably from 1 x 10 ^{-5 to} 5 x 10 ^-1 mol, most preferably from 2 x 10 ^-5 to 2 x 10 ^-1 mol.

The compounds represented by the formulas (1) to (3) can be easily synthesized by known methods. For example, US Pat. No. 5,545,515, US Pat. No. 5,635,339,
U.S. Pat. No. 5,654,130, International Publication WO 97/341
No. 96 or Japanese Patent Application No. 9-309813, Japanese Patent Application No. 9-30983
The compound can be synthesized with reference to the method described in No. 272002. The compounds represented by the formulas (1) to (3) may be used alone or in combination of two or more. In addition to the above, US Pat. No. 5,545,515 and US Pat.
No. 39, US Pat. No. 5,654,130, International Publication WO97
/ 34196, compounds described in U.S. Pat. No. 5,686,228, or Japanese Patent Application Nos. 9-228888 and 9
No. 273935, Japanese Patent Application No. 9-309813, Japanese Patent Application No. 9-296174, Japanese Patent Application No. 9-282564, Japanese Patent Application No. 9-272002, Japanese Patent Application No. 9-272003, Japanese Patent Application No. 9-332388. The compounds described in the above items may be used in combination.

The nucleating agent used in the present invention may be a hydrazine derivative. In that case, the following hydrazine derivatives are preferably used. The hydrazine derivative preferably used in the present invention can also be synthesized by various methods described in the following patents. Tokiko 6-7713
A compound represented by Chemical formula 1 described in No. 8 and specifically described on pages 3 and 4 of the same publication. A compound represented by the general formula (I) described in JP-B-6-93082;
Compounds 1-38 on pages 8-18. Compounds represented by the general formulas (4), (5) and (6) described in JP-A-6-230497, specifically the compound 4- described on pages 25 and 26 of the same publication. 1 to compound 4-10, compound 5 described on pages 28 to 36
-1 to 5-42, and compounds 6-1 to 6-7 described on pages 39 and 40. Compounds represented by general formulas (1) and (2) described in JP-A-6-289520, specifically, from page 5 to
Compounds 1-1) to 1-17) and 2-1) described on page 7. JP Hei 6
Compounds represented by (Chemical Formula 2) and (Chemical Formula 3) described in JP-A-313936, specifically, compounds described on pages 6 to 19 of the same publication.
Compounds represented by (Chemical Formula 1) described in JP-A-6-313951, specifically, compounds described on pages 3 to 5 of the same. JP
Compounds represented by formula (I) described in No. 7-5610, specifically, compounds I-1 to I-38 described on pages 5 to 10 of the same publication.
A compound represented by the general formula (II) described in JP-A-7-77783, specifically, a compound II-1 described on pages 10 to 27 of the publication;
~ II-102. Compounds represented by formulas (H) and (Ha) described in JP-A-7-104426, specifically, compounds H-1 to H-44 described on pages 8 to 15 of the same publication. JP 9-2208
The compound described in No. 2 which is characterized by having an anionic group or a nonionic group which forms an intramolecular hydrogen bond with a hydrogen atom of hydrazine in the vicinity of the hydrazine group. B), compounds represented by the general formulas (C), (D), (E) and (F), specifically the compounds N-1 to N-30 described in the publication . A compound represented by the general formula (1) described in JP-A-9-22082,
Specifically, compounds D-1 to D-55 described in the publication. One more
Various hydrazine derivatives described on pages 25 to 34 of "Known Techniques (pages 1 to 207)" (Aztec) published on March 22, 991. Compounds D-2 and D-39 of JP-A-62-86354 (pages 6 to 7).

The hydrazine derivative preferably used in the present invention may be any suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethylsulfoxide, methylcellosolve. It can be used by dissolving it in such as.

Also, the well-known emulsification dispersion method is used.
Therefore, dibutyl phthalate, tricresyl phosphate
Or glyceryl triacetate or diethyl cover
Oils such as ethyl acetate and cyclohexanone
Dissolve with any cosolvent and mechanically create an emulsified dispersion.
It can be manufactured and used. Or as a solid dispersion method
The hydrazine derivative powder is prepared by a known method.
Ball mill, colloid mill or ultrasonic in water
Therefore, they can be dispersed and used. Preferably used in the present invention
The hydrazine derivative is used to form an image on a support.
Any layer of the image forming layer or other binder layer on the layer side
To the image forming layer or adjacent thereto.
It is preferably added to the binder layer. In the present invention
The amount of the hydrazine derivative preferably used is silver 1
1 × 10 per mole^-6~ 1 × 10^-2Mole is preferred, 1 × 10^-Five
~ 5 × 10^-3Mole is more preferred, 2 × 10^-Five ~ 5 × 10^-3Mole
Is most preferred.

Further, the present invention provides a method for forming a super-high contrast image.
A high contrast accelerator can be used in combination with the nucleating agent. For example, amine compounds described in U.S. Patent No. 5,545,505, specifically AM-1 to AM-5, hydroxamic acids described in 5,545,507, specifically HA-1 to HA-11,
Acrylonitrile described in 5,545,507, specifically CN-1 to CN-13, hydrazine compound described in 5,558,983, specifically CA-1 to CA-6, JP-A-9-29736
8. Onium salts according to 8, specifically A-1 to A-42,
B-1 to B-27, C-1 to C-14 and the like can be used.
The synthesis method, addition method, addition amount and the like of these high contrast enhancement agents can be carried out as described in each of the cited patents.

In the present invention, an acid or a salt thereof formed by hydration of diphosphorus pentoxide is preferably used in combination with a nucleating agent. Acids or salts thereof formed by hydration of diphosphorus pentoxide include metaphosphoric acid (salt), pyrophosphoric acid (salt), orthophosphoric acid (salt), triphosphoric acid (salt), tetraphosphoric acid (salt),
Hexametaphosphoric acid (salt) and the like. Particularly preferred acids or salts thereof formed by hydration of diphosphorus pentoxide include orthophosphoric acid (salt) and hexametaphosphoric acid (salt). Specific salts include sodium orthophosphate, sodium dihydrogen orthophosphate, Examples include sodium hexametaphosphate and ammonium hexametaphosphate.

The acid or salt thereof formed by hydration of diphosphorus pentoxide, which can be preferably used in the present invention, is added to the image forming layer or the binder layer adjacent thereto from the viewpoint that the desired effect is exhibited in a small amount. . The amount of the acid or salt thereof formed by hydration of diphosphorus pentoxide used in the present invention (the coating amount per 1 m ^{2 of the} light-sensitive material) may be a desired amount according to the performance such as sensitivity and fog. ~ 500mg
/ m ² is preferable, and 0.5 to 100 mg / m ² is more preferable.

The photothermographic material of the present invention preferably contains a reducing agent for an organic silver salt. The reducing agent for the organic silver salt may be any substance that reduces silver ions to metallic silver, preferably an organic substance. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred. The reducing agent is preferably contained in an amount of 5 to 50 mol%, more preferably 10 to 40 mol%, per 1 mol of silver on the surface having the image forming layer. The layer to which the reducing agent is added may be any layer on the side having the image forming layer. When it is added to a layer other than the image forming layer, it is preferable to use a relatively large amount of 10 to 50 mol% with respect to 1 mol of silver. Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material using an organic silver salt, a wide range of reducing agents are disclosed in JP-A-46-6074 and JP-A-47-1238.
47-33621, 49-46427, 49-115540, 50-14
No. 334, No. 50-36110, No. 50-147711, No. 51-32632,
No. 51-1023721, No. 51-32324, No. 51-51933, No. 52-8
4727, 55-108654, 56-146133, 57-82828
No. 57-82829, JP-A-6-3793, U.S. Pat.
No. 6, 3,751,252, 3,751,255, 3,761,270,
3,782,949, 3,839,048, 3,928,686, 5,4
No. 64,738, German Patent 2321328, European Patent 692732 and the like. For example, phenylamide oxime,
Amide oximes such as 2-thienylamide oxime and p-phenoxyphenylamide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; 2,2′-bis (hydroxymethyl) propionyl-β-
A combination of an aliphatic carboxylic acid aryl hydrazide such as a combination of phenylhydrazine and ascorbic acid with ascorbic acid; a combination of polyhydroxybenzene with hydroxylamine, reductone and / or hydrazine (eg, hydroquinone and bis (ethoxyethyl) hydroxyl Amines, piperidinohexose reductone or a combination of formyl-4-methylphenylhydrazine); hydroxamic acids such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-alinine hydroxamic acid; azine and sulfonamide phenol (E.g., phenothiazine and 2,6-dichloro-4-
Benzenesulfonamidophenol); ethyl-α-
Α-cyanophenylacetic acid derivatives such as cyano-2-methylphenylacetate and ethyl-α-cyanophenylacetate; 2,2′-dihydroxy-1,1′-binaphthyl, 6,6′-dibromo-2,2′- Dihydroxy-1,1'-binaphthyl and bis (2
Bis-β-naphthol as exemplified by -hydroxy-1-naphthyl) methane; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (eg, 2,4-dihydroxybenzophenone or 2 ′, 4′-dihydroxy Acetophenone); 5-pyrazolone, such as 3-methyl-1-phenyl-5-pyrazolone; dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone. Reductones as exemplified; sulfonamide phenol reducing agents such as 2,6-dichloro-4-benzenesulfonamidophenol and p-benzenesulfonamidophenol; 2-phenylindane-1,3-dione and the like; 2,2- Chromanes such as dimethyl-7-t-butyl-6-hydroxychroman; 2,6-dimethoxy-3,5-dicarboethoxy-1,4-dihydrogen 1,4-dihydropyridines such as lopyridine; bisphenols (eg, bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4 , 4-Ethylidene-bis (2-t-butyl-6-methylphenol), 1,1, -bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 2,2 -Bis (3,5-dimethyl-4-hydroxyphenyl) propane, etc.); ascorbic acid derivatives (eg, 1-ascorbyl palmitate, ascorbyl stearate, etc.); and aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and Certain indane-1,3-diones; chromanol (such as tocopherol).
Particularly preferred reducing agents are bisphenol and chromanol.

The reducing agent used in the present invention may be added by any method such as a solution, a powder, and a dispersion of solid fine particles. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

When an additive known as a "toning agent" for improving an image is contained, the optical density may be increased. The toning agent may also be advantageous in forming a black silver image. The toning agent is preferably contained in an amount of 0.1 to 50% mol per mol of silver on the surface having the image forming layer,
More preferably, it is contained in an amount of 0.5 to 20% by mole. Further, the toning agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material using an organic silver salt, a wide range of color toning agents are disclosed in JP-A-46-6077 and JP-A-47-10282.
Nos. 49-5019, 49-5020, 49-91215, 49-9
No. 1215, No. 50-2524, No. 50-32927, No. 50-67132,
No. 50-67641, No. 50-114217, No. 51-3223, No. 51-279
No. 23, No. 52-14788, No. 52-99813, No. 53-1020, No. 5
3-76020, 54-156524, 54-156525, 61-1836
No. 42, JP-A-4-56848, JP-B-49-10727, 54-2033
No. 3, U.S. Pat.Nos. 3,080,254, 3,446,648, 3,782,9
No. 41, No. 4,123,282, No. 4,510,236, British Patent 138079
No. 5, Belgian Patent No. 841910 and the like. Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazolin-5-one, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinedione Cyclic imides such as; naphthalimides (eg, N
-Hydroxy-1,8-naphthalimide); cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-
Mercapto-1,2,4-triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole N- (aminomethyl) aryldicarboximides, such as (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-dicarboximide ); And blocked pyrazoles, isothiuronium derivatives and certain photobleaching agents (eg, N, N'-hexamethylenebis (1-
Carbamoyl-3,5-dimethylpyrazole), 1,8- (3,6-diazaoctane) bis (isothiuronium trifluoroacetate) and 2-tribromomethylsulfonyl)-(benzothiazole)); and 3-ethyl- 5 [(3-ethyl-2-benzothiazolinylidene) -1-methylethylidene] -2-thio-2,4
-Oxazolidinedione; phthalazinone, phthalazinone derivative or metal salt, or 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione A combination of phthalazinone and a phthalic acid derivative (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride, etc.); phthalazine,
Phthalazine derivatives (e.g., 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine,
6-iso-butylphthalazine, 6-iso-propylphthalazine,
6-tert-butylphthalazine, 5,7-dimethylphthalazine,
And metal salts; and phthalazine and its derivatives with phthalic acid derivatives (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride). Combinations; quinazolinedione, benzoxazine or naphthoxazine derivatives; rhodium complexes, such as hexachlororhodium, which function not only as color-toning agents but also in-situ as sources of halide ions for silver halide formation
(III) ammonium, rhodium bromide, rhodium nitrate and potassium hexachlororhodate (III); inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide; 1,3-benzoxazine- 2,4-
Benzoxazine-2,4-diones such as dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione; pyrimidine and asymmetric -Triazines (e.g., 2,4-dihydroxypyrimidine,
2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (e.g., 3,6-
Dimercapto-1,4-diphenyl-1H, 4H-2,3a, 5,6a-tetraazapentalene, and 1,4-di (o-chlorophenyl) -3,6
-Dimercapto-1H, 4H-2,3a, 5,6a-tetraazapentalene).

The toning agent used in the present invention may be added by any method such as a solution, a powder, and a solid fine particle dispersion. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

The surface pH of the photothermographic material of the present invention before the heat development processing is preferably 6 or less from the viewpoint of reducing fogging during storage, particularly 5.5 or less, more preferably 5.3 or less. It is. There is no particular lower limit, but 3
It is about. The adjustment of the film surface pH is preferably performed using an organic acid such as a phthalic acid derivative, a nonvolatile acid such as sulfuric acid, or a volatile base such as ammonia from the viewpoint of reducing the film surface pH. In particular, ammonia is preferable for achieving a low film surface pH since ammonia is easily volatilized and can be removed before the application step and the heat development.

The pH of the film surface of the photothermographic material of the present invention
When measuring the photothermographic material 2.5 mm × 2.5 cm before the heat development processing, the film was folded into a boat shape, 300 μl of distilled water was dropped on the image forming layer side, and the solution was allowed to stand for 30 minutes. It is preferable to measure the dropped solution for 1 minute with a pH BOY-P2 (a semiconductor type pH meter manufactured by Shindengen Kogyo Co., Ltd.).

As the binder used for the photothermographic material of the present invention, the following polymer latex is preferably used. At least one of the image forming layers containing the photosensitive silver halide of the photothermographic material of the present invention.
The layer contains the polymer latex described below for all binders.
The image forming layer is preferably used in an amount of 50% by weight or more. (Hereinafter, this image forming layer is referred to as “image forming layer in the present invention”, and the polymer latex used as a binder is referred to as “polymer latex used in the present invention.”) The polymer latex is not limited to the image forming layer, but may be a protective layer or a backing layer. When the photothermographic material of the present invention is used for printing in which dimensional change is a problem, it is preferable to use a polymer latex for the protective layer and the back layer. However, the "polymer latex" referred to here is a water-insoluble hydrophobic polymer dispersed as fine particles in a water-soluble dispersion medium. The dispersion state is such that the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or partially dispersed in polymer molecules and molecular chains themselves are molecularly dispersed. Any of them may be used. For the polymer latex used in the present invention, `` Synthetic resin emulsion (Hei Okuda, edited by Hiroshi Inagaki, published by Polymer Publishing Association (1978)) '', `` Application of synthetic latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki,
(Edited by Keiji Kasahara, published by the Society of Polymer Publishing (1993)), `` Chemistry of Synthetic Latex (Souichi Muroi, published by the Society of Polymer Publishing (197)
0)) ”. The average particle size of the dispersed particles is 1 to
The range is preferably 50,000 nm, more preferably about 5 to 1000 nm. There is no particular limitation on the particle size distribution of the dispersed particles, and those having a wide particle size distribution or those having a monodispersed particle size distribution may be used.

The polymer latex used in the present invention may be a so-called core / shell type latex other than the polymer latex having a normal uniform structure. In this case, it may be preferable to change the glass transition temperature of the core and the shell. The glass transition temperature (Tg) of the polymer latex preferably used as a binder in the photothermographic material of the present invention differs between the protective layer, the back layer and the image forming layer. In the image forming layer, the temperature is preferably -30 to 40 ° C. in order to promote diffusion of the photographically useful material during thermal development. When used for the protective layer or the back layer, a glass transition temperature of 25 to 70 ° C. is preferable for contacting various devices. Minimum film forming temperature of polymer latex used in the present invention
(MFT) is preferably -30 ° C to 90 ° C, more preferably about 0 ° C to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. The film-forming aid is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of the polymer latex, also called a plasticizer, and is described in, for example, `` Synthesis of Synthetic Latex (Souichi Muroi, published by Polymer Publishing Association (1970) )"It is described in.

Examples of the polymer used in the polymer latex used in the present invention include acrylic resin, vinyl acetate resin, polyester resin, polyurethane resin, rubber resin, vinyl chloride resin, vinylidene chloride resin, polyolefin resin, and copolymers thereof. and so on. The polymer may be a linear polymer, a branched polymer, or a crosslinked polymer. The polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized. In the case of a copolymer, it may be a random copolymer or a block copolymer. The molecular weight of the polymer is preferably from 5000 to 100000, more preferably from about 10,000 to 100,000 in number average molecular weight. If the molecular weight is too small, the mechanical strength of the image forming layer is insufficient, and if it is too large, the film-forming properties are poor, which is not preferable.

Specific examples of the polymer latex used as a binder for the image forming layer of the photothermographic material of the present invention include the following. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer, latex of styrene / butadiene / acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer Latex of methyl methacrylate / vinyl chloride / acrylic acid copolymer, latex of vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer, and the like. Such polymers are also commercially available, and the following polymers can be used. For example, as examples of acrylic resin, Sebian A-4635,46583,4601 (all manufactured by Daicel Chemical Industries, Ltd.), Nipol Lx811,814,821,820,8
Polyester resins include FINETEX ES650, 611, 675, and 850 (all manufactured by Dainippon Ink and Chemicals), WD-size, WMS (all manufactured by Eastman Chemical) , HYDRAN AP1 as polyurethane resin
0, 20, 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.)
LACSTAR 7310K, 3307B, 4700H, 713 as rubber resin
2C (Dai Nippon Ink Chemical Co., Ltd.), Nipol Lx416, 41
0, 438C, 2507, (Nippon Zeon Co., Ltd.) and other vinyl chloride resins such as G351 and G576 (Nippon Zeon Co., Ltd.)
L502, L513 (manufactured by Asahi Kasei Kogyo Co., Ltd.), Aron D7020, D504, D5071 (manufactured by Mitsui Toatsu Co., Ltd.) Mitsui Petrochemical Co., Ltd.). These polymers may be used alone or as a blend of two or more as necessary.

In the image forming layer of the present invention, the above polymer latex is preferably used as 50% by weight or more of the whole binder, and more preferably 70% by weight or more of the above polymer latex. In the image forming layer in the present invention, if necessary, 50% by weight of all binders
%, A hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose and hydroxypropylmethylcellulose may be added. The amount of the hydrophilic polymer to be added is preferably 30% by weight or less, more preferably 15% by weight or less of the total binder in the image forming layer.

The image forming layer in the present invention is preferably prepared by applying an aqueous coating solution and then drying. However, the `` water-based '' here is 60% by weight of the solvent (dispersion medium) of the coating liquid.
It means that the above is water. As components other than water of the coating solution, water-miscible organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used. Specific examples of the solvent composition include the following. Water / methanol = 90/10, water / methanol = 70/30, water / ethanol = 90/10, water / isopropanol = 90/10, water / dimethylformamide = 95
/ 5, water / methanol / dimethylformamide = 80/15 /
5, water / methanol / dimethylformamide = 90/5/5.
(However, the numbers represent% by weight.) The total binder amount of the image forming layer in the present invention is 0.2 to 30 g.
/ M ² , more preferably in the range of 1 to 15 g / m ² . A crosslinking agent for crosslinking and a surfactant for improving coating properties may be added to the image forming layer.

As the sensitizing dye in the present invention, any dye can be used as long as it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holo-holerocyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye, and the like can be used. Useful sensitizing dyes for use in the present invention include, for example, RESEARCH DISCLOSURE Item 17
Item 643IV-A (p.23, December 1978), Item 1831X (August 1979)
p.437) or in the literature cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers, scanners, imagesetters and plate making cameras can be advantageously selected. Examples of spectral sensitization to red light, He-Ne laser, for a so-called red light source such as red semiconductor laser and LED, the I-1 to I-38 described in JP-A-54-18726 Compound, compounds of I-1 to I-35 described in JP-A-6-75322 and compounds of I-1 to I-34 described in JP-A-7-287338, dyes described in JP-B-55-39818 1 to 20, JP-A-62-2
Compounds of I-1 to I-37 described in 284343 and JP-A-7-2
Compounds I-1 to I-34 described in 87338 are advantageously selected.

For a semiconductor laser light source in the wavelength region of 750 to 1400 nm, cyanine, merocyanine, styryl,
A variety of known dyes, including hemicyanine, oxonol, hemioxonol and xanthene dyes, can be spectrally sensitized favorably. Useful cyanine dyes are, for example, cyanine dyes having a basic nucleus, such as a thiazoline nucleus, an oxazoline nucleus, a pyrroline nucleus, a pyridine nucleus, an oxazole nucleus, a thiazole nucleus, a selenazole nucleus and an imidazole nucleus. Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus. Including. Among the above-mentioned cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Pat.
3,719,495, 3,877,943, British Patent 1,466,201,
No. 1,469,117, No. 1,422,057, No. 3-10391, No. 6
-52387, JP-A-5-341432, JP-A-6-94781, JP-A-6-3011
The dye may be appropriately selected from known dyes as described in No. 41.

Particularly preferred as the structure of the dye used in the present invention is a cyanine dye having a thioether bond-containing substituent (for example, see JP-A-62-58239 and JP-A-3-13863).
No.8, No.3-138642, No.4-255840, No.5-72659, No.5-
No. 72661, No. 6-222491, No. 2-230506, No. 6-258757
No., 6-317868, 6-324425, Tokuyohei 7-500926,
Dyes described in U.S. Pat.No. 5,541,054), dyes having a carboxylic acid group (for example, JP-A-3-163440, 6-30114
No. 1, U.S. Pat.No. 5,441,899), merocyanine dyes, polynuclear merocyanine dyes and polynuclear cyanine dyes
(JP 47-6329, JP 49-105524, JP 51-127719, JP
52-80829, 54-61517, 59-214846, 60-6750
No. 63-159841, JP-A-6-35109, JP-A-6-59381,
And the dyes described in JP-A-7-146537, JP-A-7-146537, JP-T-55-50111, British Patent 1,467,638, and US Patent 5,281,515. Further, as a dye forming a J-band, U.S. Pat. These dyes can be preferably used in the present invention.

These sensitizing dyes may be used alone.
Two or more kinds may be used in combination. Combinations of sensitizing dyes are often used, especially for supersensitization. In addition to the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are Re.
search Disclosure Volume 176, 17643 (Issued December 1978) Page 23
IV, J, or JP-B-49-25500, JP-B-43-4933, JP-A-59-19032, and JP-A-59-192242.
The sensitizing dyes may be added to the silver halide emulsion by dispersing them directly in the emulsion or by adding water, methanol, ethanol, propanol, acetone, methylcellosolve, 2,2,3,3. -Tetrafluoropropanol, 2,
2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, dissolved in a solvent alone or a mixture of solvents such as N-dimethylformamide It may be added to the emulsion.

As disclosed in US Pat. No. 3,469,987, a dye is dissolved in a volatile organic solvent, this solution is dispersed in water or a hydrophilic colloid, and this dispersion is dispersed in an emulsion. To Japanese Patent Publication No. 44-23389,
As disclosed in JP-A-44-27555 and JP-A-57-22091, the dye is dissolved in an acid and this solution is added to the emulsion, or an acid or base is added to the emulsion as an aqueous solution in the presence of an acid or base. A method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to an emulsion, as disclosed in U.S. Patent Nos. 3,822,135 and 4,006,025, JP-A-53-102733. JP-A-51-746, a method in which a dye is directly dispersed in a hydrophilic colloid and the dispersion is added to an emulsion as disclosed in JP-A-58-105141.
As disclosed in Japanese Patent No. 24, a method in which a dye is dissolved using a compound that causes a red shift, and this solution is added to an emulsion can also be used. Also, ultrasonic waves can be used for dissolution.

The sensitizing dye may be added to the silver halide emulsion at any time during the preparation of the emulsion which has been found to be useful. US Patent
2,735,766, 3,628,960, 4,183,756, 4,22
No. 5,666, JP-A-58-184142, JP-A-60-196749, etc., as disclosed in the silver halide grain forming step or / and the time before the desalting, during the desalting step and / or during the desalting step. Alternatively, from the time after desalination to before the start of chemical ripening,
As disclosed in the specification such as -113920, the timing immediately before or during chemical ripening, at any time after the chemical ripening and before coating, the emulsion is added at any time during the process. Is also good. Also, U.S. Patent 4,225,666
As disclosed in the specification such as JP-A-58-7629, the same compound may be used alone or in combination with a compound having a different structure, for example, during the particle forming step and during the chemical ripening step or when the chemical ripening is completed. May be added separately, such as before or after chemical ripening or during the process and after completion, or may be added by changing the type of compound and compound combination to be added and divided. Good. The amount of the sensitizing dye used in the present invention may be a desired amount in accordance with performance such as sensitivity and fog, but is preferably 10 ^-6 to 1 mol, more preferably 10 ^-4 to 1 mol per mol of silver halide in the image forming layer. 10 ^-1 mol is more preferred.

In the present invention, a supersensitizer can be used to improve the infrared spectral sensitization efficiency. The supersensitizer used in the present invention is disclosed in EP 587338 and U.S. Pat.
And compounds selected from heteroaromatic or aliphatic mercapto compounds, heteroaromatic disulfide compounds, stilbene, hydrazine, and triazine. Particularly preferred supersensitizers include heteroaromatic mercapto compounds disclosed in JP-A-5-341432, heteroaromatic disulfide compounds, stilbene compounds disclosed in JP-A-10-73899, and Japanese Patent Application No. 10-73899. Compounds represented by the general formula (I) described in No. 78168, specifically, compounds 1 to 57 described in the same specification
It is. The addition amount of these supersensitizers is preferably in the range of 0.0001 to 1.0 mol per mol of silver in the emulsion layer, more preferably 0.001 to 0.3 mol per mol of silver.

The silver halide emulsion used in the present invention and / or
And the organic silver salts can be further protected against the formation of additional fog by antifoggants, stabilizers and stabilizer precursors, and can be stabilized against reduced sensitivity during stock storage. Suitable antifoggants, stabilizers and stabilizer precursors that can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716, U.S. Pat. Azaindene, U.S. Pat.
8,663 mercury salt, U.S. Pat.No. 3,287,135 urazole, U.S. Pat.
Nitrone, nitroindazole, U.S. Patent No. 2,839,405
No. 3,220,839, thiuronium salts, and U.S. Pat.Nos. 2,566,263 and 2,597,915, palladium, platinum and gold salts, U.S. Pat.Nos. 4,108,665 and 4,442,202 No. 4,128,557
Nos. 4,137,079 and 4,138,365 and 4,
No. 4,59,350 and U.S. Pat.
And the phosphorus compounds described in 1,985.

The antifoggant preferably used in the present invention is an organic halide.
19624, 50-120328, 51-121332, 54-58022
Nos. 56-70543, 56-99335, 59-90842, 61
No. -129642, No. 62-129845, JP-A-6-208191, No. 7-56
No. 21, 7-2781, 8-15809, U.S. Pat.No. 5,340,712
Nos. 5,369,000 and 5,464,737. The antifoggant used in the present invention may be added by any method such as a solution, a powder, and a solid fine particle dispersion. Solid fine particle dispersion is a known fine
(For example, ball mill, vibrating ball mill, sand mill,
(Colloid mill, jet mill, roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

Although not required to practice the present invention,
It may be advantageous to add a mercury (II) salt as an antifoggant to the image forming layer. Preferred mercury (II) salts for this purpose are mercury acetate and mercury bromide. The addition amount of mercury used in the present invention is preferably 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol, more preferably 1 × 10 ⁻⁹ mol, per mol of silver coated.
The range is from × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol.

The photothermographic material of the present invention may contain benzoic acids for the purpose of increasing the sensitivity and preventing fog. The benzoic acids may be any benzoic acid derivative, but examples of preferred structures include, for example, U.S. Pat.
No. 9-329864 and JP-A-9-329864.
And compounds described in JP-A No. 9-281637. The benzoic acid may be added to any part of the photothermographic material, but it is preferable to add the benzoic acid to the layer having the image forming layer, and it is preferable to add the benzoic acid to the layer containing the organic silver salt. preferable. The benzoic acid may be added in any step of preparing the coating solution,
When it is added to the layer containing the organic silver salt, any step from the preparation of the organic silver salt to the preparation of the coating solution may be used, but it is preferable after the preparation of the organic silver salt and immediately before the coating. The benzoic acid may be added by any method such as powder, solution, and fine particle dispersion. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent and a color tone agent. The benzoic acid may be added in any amount, but preferably 1 × 10 ⁻⁶ mol or more and 2 mol or less, more preferably 1 × 10 ⁻³ mol or more and 0.5 mol or less, per 1 mol of silver.

The photothermographic material of the present invention contains a mercapto compound, a disulfide compound, a mercapto compound, a disulfide compound, or the like in order to control development by suppressing or accelerating development, to improve spectral sensitization efficiency, to improve storage stability before and after development, and the like. A thione compound can be contained. When a mercapto compound is used in the present invention, any structure may be used.
-SM and Ar-SS-Ar are preferred. Wherein M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic or fused aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogens (e.g., Br and Cl), hydroxy, amino, carboxy,
Alkyl (e.g. one or more carbon atoms, preferably 1-4
Having one carbon atom), alkoxy (eg, having one or more carbon atoms, preferably 1-4 carbon atoms) and aryl (optionally having substituents)
And a substituent selected from the group consisting of:
As mercapto-substituted heteroaromatic compounds, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-
Methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole, 2,2'-dithiobis- (benzothiazole, 3-mercapto-1,2,4-triazole, 4,5-diphenyl-2-imidazolethiol, 2- Mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto
-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate , 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole,
4-Hydrocyr-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2
-Mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole, 1-phenyl
-5-mercaptotetrazole, 3- (5-mercaptotetrazole) -sodium benzenesulfonate, N-methyl-N'-
Examples include [3- (5-mercaptotetrazolyl) phenyl] urea, 2-mercapto-4-phenyloxazole, and the like, but the present invention is not limited thereto. The addition amount of these mercapto compounds is 0.00 per mole of silver in the emulsion layer.
The range is preferably from 001 to 1.0 mole, more preferably from 0.001 to 0.3 mole per mole of silver.

In the image forming layer according to the invention, a polyhydric alcohol (for example, US Pat.
Glycerin and diols of the type described in U.S. Pat. No. 2,960,404), fatty acids or esters described in U.S. Pat. Nos. 2,588,765 and 3,121,060, and silicone resins described in British Patent No. 955,061. In the present invention, it is preferable to provide a protective layer on the image forming layer, as the binder of the protective layer, as described above, it is preferable to use a polymer latex having a glass transition temperature of 25 ° C or more and 70 ° C or less. . In this case, it is preferable to use the polymer latex described above in an amount of 50% by weight or more, preferably 70% by weight or more of the total binder in the protective layer. In the present invention, it is preferable to provide at least one such protective layer. The binder configuration and coating method of such a protective layer are the same as those of the image forming layer. As the polymer latex for the protective layer, an acrylic, styrene, acryl / styrene, vinyl chloride, or vinylidene chloride polymer latex is preferably used. Specifically, acrylic resin-based VONCORT R3370, 4280, Nipo
l Lx857, methyl acrylate / 2-ethylhexyl (meth) acrylate / hydroxyethyl (meth) acrylate / styrene / (meth) acrylic acid copolymer,
Nipol G576 as a vinyl chloride resin and Aron D5071 as a vinylidene chloride resin are preferably used. The total amount of the binder for the protective layer used in the present invention is in the range of 0.2 to 5.0 g / m ² , more preferably 0.5 to 4.0 g / m ² .

In the surface protective layer of the present invention, any anti-adhesion material may be used. Examples of anti-adhesion materials include wax, silica particles, styrene-containing elastomeric block copolymers (e.g., styrene-butadiene-styrene, styrene-isoprene-styrene), cellulose acetate, cellulose acetate butyrate, cellulose propionate and the like. And mixtures. Further, a crosslinking agent for crosslinking and a surfactant for improving coating properties may be added to the surface protective layer. In the image forming layer or the protective layer of the image forming layer in the present invention, a light absorbing material and a filter dye as described in U.S. Pat. It can be used in photographic elements, including: Also, for example, U.S. Patent No. 3,282,699
The dye can be mordanted as described in the item. As the amount of the filter dye used, the absorbance at the exposure wavelength is 0.1 to 3
Is preferred, and 0.2 to 1.5 is particularly preferred.

The image forming layer in the present invention has improved color tone,
Various dyes and pigments can be used from the viewpoint of prevention of irradiation. Dyes and pigments used in the image forming layer may be any, for example, pigments and dyes described in the color index, specifically, pyrazoloazole dye, anthraquinone dye, azo dye, azomethine dye,
Oxonol dyes, carbocyanine dyes, styryl dyes, triphenylmethane dyes, indoaniline dyes, indophenol dyes, organic pigments including phthalocyanine, and inorganic pigments. Preferred dyes used in the present invention include anthraquinone dyes (e.g., compounds 1 to 9 described in JP-A-5-341441, compounds 3-6 to 18 and 3-23 to 38 described in JP-A-5-165147), azomethine Dyes (e.g., compounds 17 to 47 described in JP-A-5-341441) and indoaniline dyes (e.g., compound 11 described in JP-A-5-289227).
To 19, compound 47 described in JP-A-5-341441, JP-A-5-1651
No. 47, compounds 2-10 to 11) and azo dyes (JP-A No.
Compounds 10 to 16) described in 5-341441 are exemplified. As a method for adding these dyes, any method such as a solution, an emulsion, a solid fine particle dispersion, and a state in which the dye is mordanted with a polymer mordant may be used. The amount of these compounds is determined by absorption of the objects, but generally the light-sensitive material 1 m ² per 1 × 10
It is preferable to use in the range of ^-6 g to 1 g.

The photothermographic material of the present invention is a so-called one-sided photosensitive material having at least one image forming layer containing a silver halide emulsion on one side of a support and a back layer on the other side. Preferably, there is. In the present invention, the back layer preferably has a maximum absorption in a desired range of about 0.3 or more and 2.0 or less. When the desired range is 750 to 1400 nm, the optical density at 750 to 360 nm is 0.005 or more.
It is preferably less than 0.5, more preferably 0.001
It is preferable that the antihalation layer has an optical density of at least 0.3 and less than 0.3. When the desired range is 750 nm or less, the maximum absorption of the desired range before image formation is 0.3 or more and 2.0 or more.
The antihalation layer is preferably such that the optical density at 360 to 750 nm after image formation is 0.005 or more and less than 0.3. The method for lowering the optical density after image formation to the above range is not particularly limited. For example, as described in Belgian Patent No. 733,706, a method in which the density of a dye is reduced by decolorization by heating, -17833
And the method of reducing the density by decoloring by light irradiation described in (1).

When an antihalation dye is used in the present invention, the dye has a desired absorption in a desired range, has a sufficiently low absorption in the visible region after treatment, and has a desirable absorbance spectrum shape of the back layer. Any compound can be used as long as it is possible. For example, the following are disclosed, but the present invention is not limited thereto. As a single dye, JP-A-59-56458, JP-A-2-216140, 7-13
No. 295, No. 7-11432, U.S. Pat.No.5,380,635, JP-A-2-688539, page 13, lower left column, line 1 to page 14, lower left column
On the ninth line, JP-A-3-24539, there are compounds described in the lower right column of page 14 to the lower right column of page 16, and as the dye which can be decolorized by the treatment, JP-A Nos. 52-139136 and 53-132334. , 56-501480, 5
7-16060, 57-68831, 57-101835, 59-18243
6, JP-A-7-36145, JP-A-7-199409, JP-B-48-33692
No. 50-16648, Japanese Patent Publication No. 2-41734, U.S. Patent 4,088,4
Nos. 97, 4,283,487, 4,548,896, and 5,187,049.

In the present invention, suitable binders for the back layer are transparent or translucent, generally colorless, and natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as: gelatin, gum arabic, poly (vinyl) Alcohol), hydroxyethyl cellulose,
Cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride) ), Copoly (styrene-acrylonitrile),
Copoly (styrene-butadiene), poly (vinyl acetal) s (e.g., poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethane)
, Phenoxy resin, poly (vinylidene chloride), poly (epoxide) s, poly (carbonate) s, poly (vinyl acetate), cellulose esters, and poly (amide) s. The binder may be coated from water or an organic solvent or an emulsion.

When the photothermographic material of the present invention is a one-sided photosensitive material, a matting agent is added to the surface protective layer of the image forming layer and / or the back layer or the surface protective layer of the back layer in order to improve transportability. Is also good. The matting agent is generally fine particles of an organic or inorganic compound insoluble in water. Any matting agent can be used, for example, U.S. Pat.
No. 213, No. 2,701,245, No. 2,322,037, No. 3,262,782
Nos. 3,539,344, 3,767,448, etc., the organic matting agents described in each specification, 1,260,772, 2,192,241, 3,3
257,206, 3,370,951, 3,523,022, 3,769,0
Those well known in the art, such as an inorganic matting agent described in each specification such as No. 20, can be used. For example, specifically, examples of organic compounds that can be used as a matting agent include, as examples of water-dispersible vinyl polymers, polymethyl acrylate, polymethyl methacrylate, polyacrylonitrile, acrylonitrile-α-methylstyrene copolymer, and polystyrene. , Styrene-divinylbenzene copolymer, polyvinyl acetate, polyethylene carbonate, polytetrafluoroethylene, etc., examples of cellulose derivatives such as methylcellulose, cellulose acetate, cellulose acetate propionate, etc., and starch derivatives such as carboxy starch, carboxynitrophenyl Starch, urea-formaldehyde-starch reactants, and the like, gelatin hardened with a known hardener and hardened gelatin that has been coacervated and hardened into microcapsule hollow granules are preferred. Can be used. Examples of the inorganic compound include silicon dioxide, titanium dioxide, magnesium dioxide, aluminum oxide, barium sulfate, calcium carbonate, silver chloride desensitized by a known method, silver bromide, glass, and diatomaceous earth. . The above matting agents can be used by mixing different types of substances as necessary. There is no particular limitation on the size and shape of the matting agent,
Any particle size can be used. In practicing the present invention, it is preferable to use one having a particle size of 0.1 μm to 30 μm. Further, the particle size distribution of the matting agent may be narrow or wide. On the other hand, since the matting agent greatly affects the haze and surface gloss of the photosensitive material, the particle size, shape, and particle size distribution can be adjusted as needed during the preparation of the matting agent or by mixing a plurality of matting agents. preferable.

In the present invention, it is a preferred embodiment to add a matting agent to the backing layer. The matting degree of the backing layer is preferably a Beck smoothness of 1200 seconds or less and 50 seconds or more, more preferably 700 seconds or less and 100 seconds or more. It is. In the present invention, the matting agent is preferably contained in the outermost surface layer of the photothermographic material, a layer functioning as the outermost surface layer, or a layer close to the outer surface, and is contained in a layer acting as a so-called protective layer. Is preferably performed. The matte degree of the emulsion surface protective layer may be any value as long as no stardust failure occurs, but the Beck smoothness is preferably 300 seconds or more and 5,000 seconds or less, and particularly preferably 500 seconds or more and 2,000 seconds or less. is there.

The image forming layer in the invention is composed of one or more layers on a support. One layer must contain additional optional materials such as organic silver salts, silver halides, developers and binders, and toning agents, coating aids and other auxiliaries. The two-layer configuration is
The first imaging layer (usually the layer adjacent to the substrate) must contain the organic silver salt and silver halide and the second or both layers must contain some other components. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. The construction of a multicolor photothermographic material may include a combination of these two layers for each color, and may include all components in a single layer as described in U.S. Pat.No. 4,708,928. Is also good.
In the case of a multi-dye multi-color photosensitive heat-developable photographic material, each emulsion layer is
Generally, they are kept distinct from one another by using a functional or non-functional barrier layer between each photosensitive layer, as described in US Pat. No. 4,460,681. U.S. Pat.Nos. 4,460,681 and 4,374,921 show a backside resistive heating layer as shown in U.S. Pat.
ating layer) can also be used in the photothermographic image system.

In the photothermographic material of the present invention, a hardener may be used for each layer such as an image forming layer, a protective layer and a back layer. Examples of the hardener include U.S. Pat.No.4,281,060, polyisocyanates described in JP-A-6-208193, epoxy compounds described in U.S. Pat.No.4,791,042, JP-A-62-89048. For example, vinyl sulfone compounds described in US Pat. In the present invention, a surfactant may be used for the purpose of improving coating properties and charging. As the surfactant, any surfactant such as nonionic, anionic, cationic, and fluorine can be used as appropriate. Specifically, JP-A-62-170950, U.S. Patent
Fluoropolymer surfactants described in 5,380,644 and the like,
JP-A-60-244945, fluorine-based surfactants described in JP-A-63-188135, etc., polysiloxane-based surfactants described in U.S. Pat. Examples thereof include a polyalkylene oxide and an anionic surfactant.

The image forming layer and other layers in the invention can be generally coated on various supports. Typical supports include polyester films, primed polyester films, poly (ethylene terephthalate) films, polyethylene naphthalate films, cellulose nitrate films, cellulose ester films,
Including poly (vinyl acetal) film, polycarbonate film and related or resinous materials, as well as glass, paper, metal and the like. Flexible substrates, especially partially acetylated or baryta and / or α-olefin polymers, especially polyethylene, polypropylene, ethylene-butene copolymers, etc.
Paper supports coated with polymers of 10 α-olefins are typically used. The support may be transparent or opaque, but is preferably transparent. Among these, polyethylene terephthalate biaxially stretched to about 75 to 200 μm is particularly preferred. On the other hand, when a plastic film is passed through a heat developing machine at a temperature of 80 ° C. or higher, the dimensions of the film generally expand and contract. When the processed material is used for printing plate making, this expansion and contraction becomes a serious problem when performing precision multicolor printing. Therefore, in the present invention, it is preferable to use a film having a small dimensional change, which is designed to reduce internal strain remaining in the film at the time of biaxial stretching and eliminate thermal shrinkage distortion generated during thermal development. For example, polyethylene terephthalate which has been heat-treated at 100 to 210 ° C. before applying the image forming layer is preferably used. Those having a high glass transition point are also preferable, and polyether ethyl ketone, polystyrene, polysulfone,
Polyether sulfone, polyarylate, polycarbonate and the like can be used.

The photothermographic material of the present invention may contain, for example, a soluble salt (eg, chloride, nitrate, etc.) for preventing electrification.
Evaporated metal layers, U.S. Pat.Nos. 2,861,056 and 3,206,3
No. 12 ionic polymer or U.S. Pat.
Insoluble inorganic salts as described in 3,428,451, JP-A-60-25
It may have a layer containing fine particles of tin oxide described in JP-A Nos. 2349 and 57-104931. A method for obtaining a color image by using the photothermographic material of the present invention is described in JP-A-7-1329.
No. 5, page 10, left column, line 43 to 11 left column, line 40. In addition, as a stabilizer for color dye images, UK Patent No.
No. 1,326,889, U.S. Pat.Nos. 3,432,300 and 3,698,909
No. 3,574,627, No. 3,573,050, No. 3,764,33
No. 7 and No. 4,042,394. The imaging layers and other layers in the present invention can be coated by various coating operations, including dip coating, air knife coating, flow coating, or extrusion coating using a hopper of the type described in U.S. Pat. No. 2,681,294. U.S. Pat.
Two or more layers can be coated simultaneously by the methods described in 2,761,791 and GB 837,095. Additional layers in the photothermographic material of the present invention, such as a dye-receiving layer for receiving a migrating dye image, an opacifying layer if reflective printing is desired, a protective topcoat layer and a primer known in the photothermographic art Layers and the like. The light-sensitive material of the present invention is preferably capable of forming an image with only one light-sensitive material, and it is preferable that a functional layer required for image formation such as an image receiving layer does not become another light-sensitive material.

In the present invention, the exposure apparatus used for imagewise exposure may be any apparatus capable of performing exposure with an exposure time of less than 10 ^-7 seconds.
D), an exposure apparatus using a Light Emitting Diode (LED) as a light source is preferably used. In particular, LD is more preferable in terms of high output and high resolution. Any of these light sources may be used as long as it can generate light of an electromagnetic wave spectrum in a target wavelength range. For example, for LD,
Dye lasers, gas lasers, solid-state lasers, semiconductor lasers, and the like can be used. The exposure is performed by overlapping the light beams of the light source, and the overlap means that the sub-scanning pitch width is smaller than the beam diameter. For example, the overlap can be quantitatively represented by FWHM / sub-scanning pitch width (overlap coefficient) when the beam diameter is represented by a half width of beam intensity (FWHM). In the present invention, the overlap coefficient is preferably 0.2 or more.

The scanning method of the light source of the exposure apparatus used in the present invention is not particularly limited, and a cylinder outer surface scanning method, a cylinder inner surface scanning method, a plane scanning method, or the like can be used. Also,
The channel of the light source may be a single channel or a multi-channel, but in the case of a cylindrical outer surface type, a multi-channel is preferably used. The photothermographic material of the present invention has a low haze at the time of exposure and tends to cause interference fringes.
Examples of the interference fringe prevention technology include a technology disclosed in Japanese Patent Application Laid-Open No. HEI 5-113548 and the like, in which a laser beam is obliquely incident on a photosensitive material, and a technology disclosed in International Publication WO95 / 31754 and the like. Methods using a mode laser are known, and it is preferable to use these techniques.

In the heat development step of forming an image on the photothermographic material of the present invention, any method may be used for development, but usually the imagewise exposed photosensitive material is heated to develop. A preferred embodiment of the heat developing machine used is a type in which the photothermographic material is brought into contact with a heat source such as a heat roller or a heat drum.
No., Patent Publication No. 684453, JP-A-9-292695, JP-A-9-
297385 and the thermal developing machine described in WO95 / 30934, as a non-contact type, JP-A-7-13294, WO97 / 28489, WO97 / 28488 and WO97 / 28487. There is a heat developing machine. A particularly preferred embodiment is a non-contact type thermal developing machine. The preferred development temperature is 80 to
The temperature is 250 ° C, more preferably 100 to 140 ° C. The development time is preferably from 1 to 180 seconds, more preferably from 10 to 90 seconds. As a method for preventing processing unevenness due to dimensional change during thermal development of the photothermographic material of the present invention, 80 ° C or more 115
A method in which the image is heated at a temperature lower than 110 ° C. for 5 seconds or more so as not to form an image, and then thermally developed at 110 ° C. to 140 ° C. to form an image (a so-called multi-step heating method) is effective.

When the photothermographic material of the present invention is subjected to thermal development processing, it is exposed to a high temperature of 110 ° C. or more, so that a part of the components contained in the material or a part of the components decomposed by the thermal development are removed. Volatilizes. These volatile components may cause uneven development, corrode the components of the heat developing machine, precipitate at low temperatures, cause deformation of the screen as foreign matter, and adhere to the screen and become dirty. Is known to have a bad effect. In order to eliminate these effects, it is known to install a filter in the heat developing machine and optimally adjust the flow of air in the heat developing machine. These can be effectively used in combination. International Publication Nos. WO 95/30933, WO 97/21150 and JP-T-Hei 10-500496 have a first opening for introducing and discharging volatile components having binding and absorbing particles. It describes that a filter cartridge is used in a heating device that heats in contact with a film. International Publication WO96 / 12213, Tokiohei 10-50740
No. 3 discloses a filter in which a heat-conductive condensation collector and a gas-absorbing fine particle filter are combined.

Also, US Pat. No. 4,518,845 and Japanese Patent Publication No. 3-54331 have a device for removing vapor from a film, a pressurizing device for pressing the film against a heat transfer member, and a device for heating the heat transfer member. The configuration is described. International Publication WO 98/27458 describes removing fog-increasing components from the film surface that evaporate from the film.

FIG. 1 shows an example of the configuration of a heat developing machine used in the heat developing process of the photothermographic material of the present invention. FIG. 1 is a side view of the heat developing machine. The thermal developing machine shown in FIG. 1 is a pair of carry-in rollers 11 (a lower roller is a heat roller) for carrying the thermal development photosensitive material 10 into a heating unit while correcting and preheating the thermal development photosensitive material 10 in a plane, and a photothermographic material after thermal development after thermal development. It has an unloading roller pair 12 that unloads the material 10 from the heating unit while correcting it into a flat shape. The photothermographic material 10 is thermally developed while being transported from the carry-in roller pair 11 to the carry-out roller pair 12. In the transporting means for transporting the photothermographic material 10 during the thermal development, a plurality of rollers 13 are provided on the side in contact with the surface having the image forming layer, and the non-woven fabric (for example, A smooth surface 14 on which polyphenylene sulfite or Teflon) is attached is installed. The back surface of the photothermographic material 10 is conveyed by sliding on the smooth surface 14 by driving a plurality of rollers 13 that come into contact with the surface having the image forming layer. As the heating means, a heater 15 is provided at an upper portion of the roller 13 and a lower portion of the smooth surface 14 so as to be heated from both sides of the photothermographic material 10. As a heating means in this case, a plate heater or the like can be used. Roller 13 and smooth surface 14
Is different depending on the member having a smooth surface, but is appropriately adjusted so that the photothermographic material 10 can be conveyed. Preferably it is 0 to 1 mm.

The material of the surface of the roller 13 and the smooth surface 14
May be any material as long as it has high-temperature durability and does not hinder the conveyance of the photothermographic material 10, but the material of the roller surface is silicon rubber, and the material of the smooth surface is a nonwoven fabric made of aromatic polyamide or Teflon (PTFE). Is preferred. It is preferable to use a plurality of heaters as the heating means and to set the heating temperature freely. The preliminary heating section upstream of the thermal development processing section is lower than the thermal development temperature (for example, 1
It is desirable to set the temperature and time to be sufficient to evaporate the amount of water in the photothermographic material, and to set the glass transition temperature (Tg) of the support of the photothermographic material 10 It is preferable that the temperature is set so as not to cause uneven development at a high temperature. Further, a guide plate 16 is provided downstream of the thermal development processing section, and a slow cooling section is further provided. The guide plate is preferably made of a material having a low thermal conductivity, and is preferably cooled gradually to prevent deformation of the photothermographic material.

Although the above has been described with reference to the illustrated examples, the present invention is not limited to this. For example, the thermal developing machine used in the present invention, such as that described in JP-A-7-13294, may have various structures. In the case of the multi-stage heating method preferably used in the present invention, in the above-described apparatus, two or more heat sources having different heating temperatures may be provided, and heating may be performed continuously at different temperatures.

[0151]

The present invention will be described in more detail with reference to the following examples.
Will be described. The materials, amounts, proportions,
Operations and the like may be changed as appropriate without departing from the spirit of the present invention.
Can be Therefore, the scope of the present invention is shown below.
The present invention is not limited to the specific examples.1. Preparation of silver halide emulsion (preparation of emulsions A to I)  <Emulsion A> Alkali-treated gelatin (calcium
11 g, potassium bromide 30 mg
And 1.24 g of sodium 4-methylbenzenesulfonate
After adjusting the pH to 6.5 at a temperature of 65 ° C, silver nitrate 18.
159 ml of an aqueous solution containing 6 g, 1 mol / l of potassium bromide and K
_ThreeIrCl₆2 × 10^-FiveKeep the aqueous solution containing mol / liter at pAg7.7
While using the control double jet method for 7 minutes
Added. Next, 476 ml of an aqueous solution containing 55.4 g of silver nitrate and bromide
Potassium 1 mol / l and K_ThreeIrCl₆2 × 10^-Five Mol / lit
Control double while maintaining aqueous solution containing pAg7.7
It was added over 30 minutes by the jet method. Then lower the pH
And subjected to desalting treatment by coagulation and sedimentation.
Low molecular weight gelatin with an average molecular weight of 15,000 (containing calcium
Adjusted to pH 5.9 and pAg 7.9.
Was. The resulting particles have an average particle size of 0.16 μm, projected area
Cubic particles with a diameter variation coefficient of 9% and a (100) face ratio of 90%
Was. The temperature of the particles obtained in this way was raised to 60 ° C.
The temperature was raised and 4-hydroxy-6-methyl-1,3,3
a, 7-tetrazaindene 5 × 10^-FourAfter adding mol, 40
The temperature was lowered to ° C. After that, keep the temperature at 40 ℃, halogen
12.5 × 10 per mole of silver halide^-FourMolar sensitizing dye A, 7.6 ×
Ten^-3Mole of compound B is added with stirring and after 20 minutes 30
The mixture was rapidly cooled to ° C. to complete the preparation of silver halide emulsion A.

<Emulsion B> A silver halide grain B having an average grain size of 0.14 μm was prepared in the same manner as the silver halide grain A, except that the grain formation temperature of the silver halide grain A was changed to 60 ° C. <Emulsion C> Silver halide grains C having an average grain size of 0.12 μm were prepared in the same manner as the silver halide grains A except that the grain formation temperature of the silver halide grains A was changed to 55 ° C. <Emulsion D> A silver halide grain D having an average grain size of 0.1 μm was prepared in the same manner as the silver halide grain A except that the grain formation temperature of the silver halide grain A was changed to 45 ° C. <Emulsion E> Silver halide grains E having an average grain size of 0.08 μm were prepared in the same manner as the silver halide grains A except that the grain formation temperature of the silver halide grains A was changed to 40 ° C. <Emulsion F> Silver halide grains F having an average grain size of 0.06 μm were prepared in the same manner as for the silver halide grains A except that the grain formation temperature of the silver halide grains A was changed to 30 ° C.

<Emulsion G> To the silver halide grains E having an average grain size of 0.08 μm, the temperature was raised to 60 ° C., and 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver. Add 154 μmol of sodium
Aged for 100 minutes, 4-hydroxy-6-methyl-1,3,3
After adding 5 × 10 ^-4 mol of 3a, 7-tetrazaindene, 4
The temperature was lowered to 0 ° C. <Emulsion H> Silver halide grains E having an average grain size of 0.08 μm
The temperature was raised to 60 ° C., 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver, and 3 minutes later, 71 μmol of triethylthiourea was added, and the mixture was ripened for 100 minutes to give 4-hydroxy-6. -Methyl-1,3,3a, 7-
After addition of 5 × 10 ⁻⁴ mol of tetrazaindene, the temperature was lowered to 40 ° C. <Emulsion I> Average grain size 0.06 μm Silver halide grains F
The temperature was raised to 60 ° C., 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver, and 3 minutes later, 71 μmol of triethylthiourea was added, and the mixture was ripened for 100 minutes to give 4-hydroxy-6. -Methyl-1,3,3a, 7-
After addition of 5 × 10 ⁻⁴ mol of tetrazaindene, the temperature was lowered to 40 ° C.

[0154]

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[0155]2. Preparation of Organic Acid Silver Dispersion <Organic Acid Silver A
>  Behenic acid manufactured by Henkel (Product name Edenor C22-85R) 8
7.6 g, distilled water 423 ml, 5N-NaOH aqueous solution 49.2 ml, tert-butyl
Mix 120 ml of chilled alcohol and stir at 75 ° C for 1 hour.
To give a sodium behenate solution. Separately, silver nitrate
206.2 ml of a 40.4 g aqueous solution was prepared and kept at 10 ° C. 63
5ml distilled water and 30ml tert-butyl alcohol
Keep the reaction vessel at 30 ° C and stir with the above sodium behenate.
The total volume of the lithium solution and the total volume of the aqueous silver nitrate solution were
It was added over 62 minutes, 10 seconds and 60 minutes, respectively. At this time, silver nitrate
7 minutes and 20 seconds after the start of aqueous solution addition, only silver nitrate aqueous solution is added
And then add the sodium behenate solution
9 minutes and 30 seconds after completion of the addition of the aqueous silver nitrate solution
Only the sodium acid solution was added. This and
The temperature inside the reaction vessel is 30 ° C and the liquid temperature does not rise
Was controlled as follows. In addition, sodium behenate
The piping of the liquid addition system is kept warm by steam tracing,
Make sure that the liquid temperature at the outlet of the addition nozzle tip is 75 ° C.
The amount of the game was controlled. Addition of silver nitrate aqueous solution
The system piping is circulated by circulating cold water outside the double pipe.
And kept warm. Addition position of sodium behenate solution and nitric acid
Silver solution is added symmetrically around the stirring axis
The height was adjusted so as not to contact the reaction solution.
After addition of the sodium behenate solution, keep the temperature
For 20 minutes, and the temperature was lowered to 25 ° C. Then, suction filtration
The solid content is separated by filtration, and the solid content of the filtrate has a conductivity of 30 μS / cm.
And washed with water. The solids thus obtained are dried
Stored as a wet cake without letting it go. The obtained bee
The morphology of silver henate particles was evaluated by electron microscopy
However, average projected area diameter 0.52 μm, average grain thickness 0.14 μm
m, scale-like crystals with a coefficient of variation of 15%
Was.

Next, a dispersion of silver behenate was prepared by the following method. To a wet cake having a dry solid content of 100 g, 7.4 g of polyvinyl alcohol (trade name: PVA-217, average degree of polymerization: about 1700) and water are added, and the total amount is 385 g.
And then predispersed with a homomixer. Next, the pressure of the predispersed undiluted solution was adjusted to 1750 kg / cm ² with a dispersing machine (trade name: Microfluidizer M-110S-EH, manufactured by Microfluidics International Corporation, using a G10Z interaction chamber), and This was repeated to obtain a silver behenate dispersion. In the cooling operation, a coiled heat exchanger was mounted before and after the interaction chamber, and the temperature of the refrigerant was adjusted to a desired dispersion temperature. The silver behenate particles contained in the silver behenate dispersion thus obtained have a volume-weighted average diameter of 0.52 μm,
The particles had a coefficient of variation of 15%. Particle size measurement is Mal
Vern Instruments Ltd. made MasterSizerX. When evaluated by electron microscopy, the ratio of the long side to the short side is
The particle had a thickness of 0.14 μm and an average aspect ratio of 5.1 (the ratio of the circle equivalent diameter of the projected area of the particle to the particle thickness) was 5.1.

[0157]3. 1,1-bis (2-hydroxy-3,5-dimethyl
Ruphenyl) -3,5,5-trimethylhexane: reducing agent solid fine
Preparation of particle dispersion  1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-
Kuraray's MP poly for 25 g of trimethylhexane
25 g of a 20 wt% aqueous solution of MP-203 from Nisshin Chemical Co., Ltd.
0.1 g of Finol 104E, 2 g of methanol and 48 ml of water were added.
The mixture was stirred well and left as a slurry for 3 hours. That
After that, prepare 360g of 1mm zirconia beads and prepare slurry
Put together in the vessel and disperser (1 / 4G sand grinder)
Dermill: Imex Co., Ltd.) for 3 hours
An agent solid fine particle dispersion was prepared. Particle size is 80wt of particle
% Was 0.3 μm or more and 1.0 μm or less.

[0158]4. Solid fine particles of polyhalogen compounds
Preparation of powder  Kuraray Co., Ltd. for 30g of polyhalogen compound-A
4 g of MP-203 of MP polymer, 0.25 g of compound C, and 66 g of water
Add and stir well, then add 0.5mm zirconia silicate
Prepare 200 g of toby beads and put it in the vessel with the slurry.
And a dispersing machine (1 / 16G sand grinder mill:
5 hours, and the solid fine particle dispersion is
Prepared. Particle size, 80% by weight of particles is 0.3μm or more and 1.0μm
It was below. Polyhalogen compound-B
Prepare solid fine particle dispersion in the same manner as halogen compound-A
And had the same particle diameter.

[0159]5. Preparation of solid fine particle dispersion of nucleating agent  For 10 g of the nucleating agent described in Table 4, polyvinyl alcohol
2.5 g of water (Kuraray PVA-217) and 87.5 g of water
And left as a slurry for 3 hours. Then, 0.5mm
Prepare 240g of luconia beads and set the slurry together with the slurry.
And a dispersing machine (1 / 4G sand grinder mill: Eye
(Mex Corporation) for 10 hours to disperse solid fine particles
Was prepared. Particle size, 80 wt% of the particles is 0.1 μm or more 1.
It was 0 μm or less and the average particle size was 0.5 μm.

[0160]6. Preparation of solid fine particle dispersion of compound Z  For 30 g of compound Z, MP polymer manufactured by Kuraray Co., Ltd.
3g of MP-203 and 87ml of water were added and stirred well,
Left for 3 hours. Then, the reducing agent solid fine particles
Dispersion of solid fine particles of compound Z in the same manner as in the preparation of the dispersion
Was prepared. The particle size is 80% by weight of the particles 0.3μm or more 1.
It was 0 μm or less.

[0161]7. Preparation of emulsion layer coating solution  Based on 1 mol of silver of the organic acid silver microcrystal dispersion prepared above
And the following binders, materials, and silver halide emulsions
Was added, and water was added to obtain an emulsion layer coating solution. Binder; Luckstar 3307B 397 g as solid content (manufactured by Dainippon Ink and Chemicals, Inc .; glass transition temperature of 17 ° C. with SBR latex) 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5 , 5-Trimethylhexane 149 g as solid content Polyhalogen compound-A 0.06 mol as solid content Polyhalogen compound-B 0.02 mol as solid content Nucleating agent Kind and amount (mol) shown in Table 4 Compound of formula (A) Table Kind and amount (mol) described in 4 sodium ethylthiosulfonate 0.30 g benzotriazole 1.04 g polyvinyl alcohol (Kuraray Co., Ltd. PVA-235) 10.8 g 6-iso-propylphthalazine 15.0 g sodium dihydrogen orthophosphate • Dihydrate 0.37 g Compound Z 9.7 g as solid content Dye A Amount of coating that gives an optical density of 783 nm of 0.3 (0.37 g as a standard) 0.06 mol as silver halide emulsions A to IAg

[0162]

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[0163]8. Preparation of coating solution for lower protective layer of emulsion surface  Methyl methacrylate / styrene / 2-ethylhexylurea
Acrylate / 2-hydroxyethyl methacrylate / ac
Particle size 120 of lylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%)
nm polymer latex solution (glass transition temperature of copolymer
Degree 57 ° C, 21.5wt% solids concentration
Compound D containing 15 wt% based on the solid content of the latex) 956 g
To H_TwoO, compound E 1.62 g, matting agent (polystyrene)
Particles, average particle size 7μm) 1.98g and polyvinyl alcohol
23.6 g of Kuraray (Kuraray Co., Ltd., PVA-235)_Two
O was added to prepare a coating solution.

[0164]9. Preparation of coating solution for protective layer on emulsion surface  Methyl methacrylate / styrene / 2-ethylhexylurea
Acrylate / 2-hydroxyethyl methacrylate / ac
Lyric acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%) particle size 70n
m polymer latex solution (copolymer glass transition temperature
54 ° C, solid content concentration 21.5wt%, used as film-forming aid
Compound D (containing 15wt% based on the solid content of latex) 630g
To H_TwoAdd O, Carnava wax (Chukyo Yushi Co., Ltd.)
Manufactured by Cellosol 524) 30 wt% solution 6.30 g, Compound E 0.72
g, compound F 7.95 g, compound G 0.01 mol, matting agent
(Polystyrene particles, average particle size 7 μm, particle size distribution 9%) 1.
18 g and polyvinyl alcohol (Kuraray Co., Ltd., PVA-2
35) Add 8.30 g and add H_TwoAdd O to prepare the coating solution
did.

[0165]

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[0166]10. PET support with backing / priming layer
Production of holding body  (1) Support Using terephthalic acid and ethylene glycol, follow standard methods.
IV (intrinsic viscosity) = 0.66 (phenol / tetrachlor
PET (measured at 25 ° C. in ethane = 6/4 (weight ratio))
Was. After pelletizing this, it was dried at 130 ° C. for 4 hours.
Then, after being melted at 300 ° C, extruded from a T-die and quenched,
An unstretched film having a thickness of 120 μm after heat setting
Ilm was made. Using rolls with different peripheral speeds,
Longitudinal stretching 3.3 times, then transverse stretching 4.5 times with a tenter
did. The temperatures at this time were 110 ° C and 130 ° C, respectively.
Was. After this, heat set at 240 ° C for 20 seconds and at the same temperature
Relaxed 4% in the lateral direction. After this, the chuck of the tenter is
After slitting, knurling both ends, 4.8kg / cm2
Rolled up. In this way, width 2.4m, length 3500m,
A roll having a thickness of 120 μm was obtained.

(2) Undercoat layer (a) Polymer latex- (1) (a core-shell type latex having a core portion of 90 wt% and a shell portion of 10 wt%, core portion: vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic) Acid = 93/3/3 / 0.9 / 0.1 (wt%), shell: weight consisting of vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic acid = 88/3/3/3/3 (wt%) Polymer latex with average molecular weight of 38000) 3.0 g / m3 as solid content^Two  2,4-dichloro-6-hydroxy-s-triazine 23mg / m^Two  Matting agent (polystyrene, average particle size 2.4 μm, particle size distribution 9%) 1.5 mg / m^Two

(3) Undercoat layer (b) Deionized gelatin (Ca²⁺Content 0.6ppm, jelly strength 230g) 50mg / m^Two  (4) Conductive layer Jurimar ET-410 (manufactured by Nippon Pure Chemical Co., Ltd.) 96mg / m^Two  Alkali-treated gelatin (molecular weight about 10,000, Ca²⁺Content 30ppm) 42mg / m^Two  Deionized gelatin (Ca²⁺Content 0.6ppm) 8mg / m^Two  Compound A 0.2mg / m^Two  Polyoxyethylene phenyl ether 10mg / m^Two  Sumitex Resin M-3 (Water-soluble melamine compound, manufactured by Sumitomo Chemical Co., Ltd.) 18mg / m^Two  Dye A Coating amount at which the optical density of 783 nm becomes 1.2 SnO2 / Sb (9/1 weight ratio, needle-like fine particles, major axis / minor axis = 20 to 30, manufactured by Ishihara Sangyo Co., Ltd.) 160 mg / m^Two  Matting agent (polymethyl methacrylate, average particle size 5μm) 7mg / m^Two

(5) Protective Layer Polymer Latex- (2) (Methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 59/9/26/5/1 (weight% copolymer) )) 1000mg / m as solid content^Two  Polystyrene sulfonate (molecular weight 1000-5000) 2.6mg / m^Two  Cellsol 524 (Chukyo Yushi Co., Ltd.) 25mg / m^Two  Sumitex Resin M-3 (Water-soluble melamine compound, manufactured by Sumitomo Chemical Co., Ltd.) 218mg / m^Two  (6) Preparation of PET support with back / undercoat layer An undercoat layer (a) and an undercoat layer (b) are provided on both sides of the support (base).
They were sequentially applied and dried at 180 ° C. for 4 minutes. About
One side on which the undercoat layer (a) and the undercoat layer (b) are applied
A conductive layer and a protective layer are sequentially applied to the surface of
Dry for 10 minutes and remove PET backing / subbing layer
Produced. The dry thickness of the undercoat layer (a) was 2.0 μm.
Was.

(7) Heat treatment for transport (7-1) Heat treatment The PET with back / undercoat layer produced in this way
Place the support in a heat treatment zone with a total length of 200 m set at 160 ° C,
It was transported at a tension of 3 kg / cm ² and a transport speed of 20 m / min. (7-2) Post heat treatment Following the heat treatment, post heat treatment was performed by passing through a zone at 40 ° C for 15 seconds, and winding was performed. The winding tension at this time is 10
kg / cm ² .

[0171]

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[0172]11. Preparation of photothermographic materials  PET support on the side where the undercoat layer (a) and the undercoat layer (b) are applied
The above emulsion layer coating solution was coated on the undercoat layer of the body by 1.6 g of silver.
/ m^TwoIt was applied so that In addition, the emulsion
Coating solution for lower layer protective layer solid content of polymer latex
1.31g / m^TwoLayer coating with emulsion coating solution
Clothed. After that, the above-mentioned emulsion layer upper layer protective layer coating solution
The solid content of the polymer latex is 3.02 g / m^Twobecome
To form a photothermographic material. The heat gained
The pH of the film surface on the image forming side of the developed photosensitive material is 4.9,
The lubricity is 660 seconds, the pH of the opposite membrane surface is 5.9,
The slip was 560.

[0173]12. Evaluation of photographic performance  (Exposure treatment) The obtained photothermographic material is
FWHM of 1/2 of the beam intensity) 12.56μm, laser output 50m
W, a single channel equipped with a semiconductor laser with an output wavelength of 783 nm
Using a laser exposure device with a tunnel inner surface method, a mirror
Exposure time and output value by changing the rotation speed of
Adjust the exposure by changing^-8Exposure in seconds
Was. The overlap coefficient at this time was set to 0.449. (Heat development processing)
A heat development process was performed using a machine. Row of heat development processing section
The surface material is silicon rubber and the smooth surface is Teflon non-woven fabric
And the pre-heating section for 14.4 seconds (pre-
The drive systems of the heating unit and the heat development processing unit are independent,
The speed difference from the image area is set to -0.5% to -1%.
Roller temperature setting, time is the first roller temperature 65 ℃, 2.4
Second, second roller temperature 78 ° C, 2.4 seconds, third roller temperature 9
5 ° C, 2.4 seconds, 4th roller temperature 109 ° C, 2.4 seconds, 5th
Roller temperature 115 ° C, 2.4 seconds, 6th roller temperature 120 ° C,
2.4 sec.), Heat development processing section 120 ℃ (photothermographic material surface
Temperature) for 13.6 seconds, slow cooling section 16 seconds (continuous from 120 ° C to 70 ° C)
Over 16 seconds, at a cooling rate of -2.45 ° C / sec.
Was subjected to a heat development process. Note that the temperature
The degree was ± 1 ° C. The setting of each roller temperature is
5 cm longer on both sides than the width of the optical material (eg 61 cm wide)
Then, apply the temperature to that part, and the temperature accuracy will come out
Caught. The temperature at both ends of each roller drops sharply.
Part that is 5cm longer than the width of the photothermographic material
Is set so that the temperature is 1-3 ° C higher than the center of the roller.
Image density of a photothermographic material (for example, in a width of 61 cm)
Care was taken to achieve a homogeneous finish.

(Evaluation of photographic performance)
The test was performed in an environment of 25 ° C., 50% RH and 20 ° C., 20% RH.
The photothermographic material was aged in the environment for at least 16 hours so that the water content of the photothermographic material was constant under the environment, and then the above-described exposure and heat development were performed. Evaluation of the obtained image was performed with a Macbeth TD904 densitometer at a visible density (about 560 nm). The measurement results were Dmin, sensitivity (evaluated by the relative value of the reciprocal of the ratio of the exposure amount giving a density higher than Dmin by 1.0, and the photothermographic material 1 shown in Table 4 was set to 100), Dmax (maximum density) , Γ (contrast: a value represented by the slope of a straight line connecting the points of density 0.2 and 2.5 with the logarithm of the exposure amount as the horizontal axis). Table 4 shows the results of the above evaluations performed on each photothermographic material.

[0175]

[Table 8]

As shown in Table 4, the photothermographic material of the present invention has a D
It can be seen that min is low, Dmax (maximum density) is high, and γ is high. In particular, it can be seen that Dmax (maximum concentration) is higher than that of the comparative sample in a 20 ° C., 20% RH environment, and the γ becomes high. From the viewpoint of sensitivity, the use of the chemically sensitized emulsion preferably used in the present invention provides higher sensitivity and higher Dmax.
Is high, which is preferable. Further, it can be seen that it is preferable to use the compounds of the formulas (1) to (3), which are preferably used in the present invention, as a nucleating agent rather than a formylhydrazine-based compound. From the above, the effect of the present invention is clear.

[0177]

According to the present invention, fog is low especially for photoengraving, especially for scanners and imagesetters.
High sensitivity and high contrast, high blackening density (Dmax),
It has become possible to provide a photothermographic material capable of obtaining photographic characteristics having a low Dmin.

[Brief description of the drawings]

FIG. 1 is a side view illustrating a configuration example of a heat developing machine.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 10 photothermographic material 11 carry-in roller pair 12 carry-out roller pair 13 roller 14 smooth surface 15 heating heater 16 guide plate A preheating section B heat development processing section C slow cooling section

Claims (5)

[Claims] In a photothermographic material having a non-photosensitive silver salt, a photosensitive silver halide and a binder on a support, the number average particle size is from 0.01 μm to 0.12 μm.
It has an image forming layer containing the following photosensitive silver halide, and contains, on the side having the image forming layer, at least one compound represented by the following formula (A) and at least one nucleating agent. A photothermographic material comprising: Embedded image [In the formula (A), R ¹ , R ² and R ³ each independently represent a hydrogen atom; a halogen atom; or a carbon atom, an oxygen atom,
Represents a substituent bonded to a benzene ring by a nitrogen atom, a sulfur atom or a phosphorus atom. X ¹ and X ² each independently represent a hydrogen atom; a halogen atom; or a substituent bonded to a benzene ring by a carbon atom, an oxygen atom, a nitrogen atom, a sulfur atom or a phosphorus atom. Provided that at least one of X ¹ and X ² is -N
It is a group represented by R ⁴ R ⁵ . R ⁴ and R ⁵ each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group,
An aryl group or —C (＝ O) —R ⁶ , —C (=
O) -C (= O) -R 6, -SO 2 -R 6, -SO-R 6,
-P (= O) (- R 6) a group represented by -R ^7.
R ⁶ and R ⁷ are each independently a group selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, an amino group, a hydroxy group, an alkoxy group, an aryloxy group and a heterocyclic oxy group. is there. These substituents may be bonded to each other to form a ring. ] 2. The photothermographic material according to claim 1, wherein the photosensitive silver halide is formed in advance and is chemically sensitized with a chemical sensitizer. 3. The photothermographic material according to claim 2, wherein the chemical sensitizer is a sulfur sensitizer represented by the following general formula (S). Embedded image [In the formula (S), R ^{11 to} R ¹⁴ each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl. Group, nitrogen-containing heterocyclic group and acyl group. R ¹¹ and R ¹² , R ¹³ and R ¹⁴ , R
¹¹ and R ¹³ or R ¹² and R ¹⁴ may combine with each other to form a 5-, 6- or 7-membered ring containing a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom. ] 4. A nucleating agent selected from a substituted alkene derivative represented by the following formula (1), a substituted isoxazole derivative represented by the following formula (2), or an acetal compound represented by the following formula (3): 4. The photothermographic material according to claim 1, wherein at least one compound is used. Embedded image [In the formula (1), R ²¹ , R ²² and R ²³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ²¹ and Z, R ²² and R
²³ , R ²¹ and R ²² , and R ²³ and Z may combine with each other to form a cyclic structure. In the formula (2), R ²⁴ is
Represents a substituent. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group,
Represents a heterocyclic oxy group, a heterocyclic thio group or a heterocyclic amino group. In the formula (3), X and Y, and A and B are
They may combine with each other to form a ring structure. ] 5. A temperature of at least -30 ° C. and at least 50% by weight of the binder of the image forming layer containing the photosensitive silver halide.
5. The photothermographic material according to claim 1, wherein a latex of a polymer having a glass transition temperature of 0 [deg.] C. or less is used.