JP2000347345A - Photosensitive heat-developable image forming material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the photosensitive heat-developable image forming material good in surface conditions and superior in storage stability for forming a photographic printing plate (especially for a scanner and an image setter) and for a medical image. SOLUTION: The photosensitive heat-developable image forming material contains (a) a photosensitive silver halide (b) a non-photosensitive reducible organic silver salt, (c) a reducing agent, (d) a binder, and (e) a dispersed antifoggant having an average particle diameter of <=0.3 μm and a maximum particle diameter of <=2 μm salt, on at least one same side of a support and this antifoggant is composed of compounds represented by the formula in which Q is an alkyl or aryl or heterocyclic group; each of X1 and X2 is, independently, a halogen atom; Z is an H atom or an electron withdrawing group; Y is a-C(=0) or -SO- or a -SO2-group; and (m) is 0 or 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a photosensitive heat-developable image forming material. More specifically, the present invention relates to a laser-exposed photosensitive heat-developable image forming material suitable for photoengraving and medical applications, which scans a laser beam and records an image on the photosensitive material.

[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 that can form a sharp black image having high resolution and sharpness. These photosensitive heat-developable materials eliminate the use of solution-based processing chemicals, and can provide customers with a simpler heat-development system that does not damage the environment.

[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.

Conventionally, in the method of forming an image by heat development, a photosensitive material is prepared by applying a coating solution using an organic solvent in most cases. The use of a solvent is not preferred, and it is desired that a photosensitive material be prepared using an aqueous coating solution. Application using an aqueous coating solution is disclosed in Japanese Patent Application No. 10-41304,
It is disclosed in Japanese Patent Application Nos. 9-287891 and 10-213487, but there are problems with the surface properties (especially pinholes) and storability of the photosensitive material, and there are still issues to be improved. ing.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems of the prior art. That is,
An object of the present invention is to provide a photosensitive heat-developable image forming material having a good surface condition and excellent storability for photoengraving (especially for scanners and imagesetters) and for medical images.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that an antifoggant having an average particle size of 0.3 μm or less and a maximum particle size of 2 μm or less is dispersed. It has been found that the use of a product can provide an excellent photosensitive heat-developable image forming material exhibiting a desired effect, and have led to the present invention. That is, the present invention, on at least one same surface of the support,
(A) photosensitive silver halide, (b) non-photosensitive reducible organic silver salt, (c) reducing agent, (d) binder, (e)
An antifoggant dispersion having an average particle size of 0.3 μm or less and a maximum particle size of 2 μm or less.
The present invention provides a photosensitive heat-developable image forming material having a thickness of not more than μm.

In the present invention, preferably, the antifoggant is a compound having a bisphenol structure in which the compound of the general formula (I) or the general formula (II) or the compound of the general formula (II) is bonded via one carbon atom. It is.

Embedded image [In the general formula (I), Q represents an alkyl group, an aryl group or a heterocyclic group, and X ₁ and X ₂ each independently represent a halogen atom. Z represents a hydrogen atom or an electron-withdrawing group. Y is -C (= O) -, - SO- or -SO ₂ - represents a. m represents 0 or 1. In the general formula (II), M represents a hydrogen atom or a k-valent cation, and R represents a substituent. n is an integer of 0 to 4, and when n ≧ 2, a plurality of R
May be the same or different. k is an integer of 1 or more, and when M is a hydrogen atom, k = 1. In one aspect of the invention, the antifoggant dispersion is a solid particulate dispersion. In another aspect of the invention, the antifoggant dispersion is an emulsified dispersion.

[0008] The photosensitive heat-developable image-forming material of the present invention preferably further comprises a super-high contrast agent. In the present invention, at least one of a substituted alkene derivative, a substituted isoxazole derivative and a specific acetal compound represented by the following general formulas (III) to (V) is preferably used as the super-high contrast agent.

Embedded image [In the general formula (III), R ¹ , R ² , and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the general formula (III), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure. In the general formula (IV), R
⁴ represents a substituent. In the general formula (V), 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. , A heterocyclic oxy group, a heterocyclic thio group, or a heterocyclic amino group. In the general formula (V), X and Y or A and B may be bonded to each other to form a cyclic structure. ]

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the following, embodiments and methods of the photosensitive heat-developable image forming material of the present invention are described in detail. The photosensitive heat-developable image forming material of the present invention is
A photosensitive silver halide, a non-photosensitive reducible organic silver salt, a reducing agent and a binder are contained on at least one same surface of the support, and the average particle size is 0 in the same plane as the support. It is characterized by containing an antifoggant dispersion having a maximum particle size of not more than 0.3 μm and a maximum particle size of not more than 2 μm, whereby a heat-developable image-forming material having no pinholes in the highest density portion can be obtained. On the other hand, if a water-soluble antifoggant is used without using an antifoggant dispersion, the image storability deteriorates, and when the antifoggant is dissolved in an organic solvent and added, the coated surface condition is greatly deteriorated. Would. Further, when using an antifoggant having an average particle size exceeding 0.3 μm and a maximum particle size exceeding 2 μm,
Pinholes occur in the highest concentration area, and the storage stability deteriorates.
The occurrence of pinholes is particularly prominent in a photographic plate-making photosensitive material containing a super-high contrast agent which is required to have a high contrast and a high maximum density, and the means of the present invention is effective.

First, the antifoggant dispersion used in the present invention will be described. The antifoggant used as the raw material of the antifoggant dispersion used in the present invention may be used alone or in combination of two or more. Further, a stabilizer or a stabilizer precursor of an antifoggant may be used in combination. Antifoggants, stabilizers and stabilizer precursors suitable for use in the present invention are described in U.S. Pat.
No. 8 and 2,694,716 thiazonium salt, U.S. Pat.Nos. 2,886,437 and 2,444,605 Azaindene, U.S. Pat.No. 2,728,663 Mercury salt,
Urazole described in U.S. Pat.No. 3,287,135, sulfocatechol described in U.S. Pat.
No. 23,448, oximes, nitrones, nitroindazoles, polyvalent metal salts described in U.S. Pat.No. 2,839,405, thyuronium salts described in U.S. Pat. Palladium, platinum and gold salts, U.S. Pat.No. 4,108,665
No. 4,442,202 and halogen-substituted organic compounds described in U.S. Pat.Nos. 4,128,557 and 4,137,079,
Nos. 4,138,365 and 4,459,350, triazines, phosphorus compounds described in U.S. Pat. No. 4,411,985, and salicylic acid derivatives of the compound of formula (I) described in Japanese Patent Application No. 11-5709.

The antifoggant dispersion used in the present invention may be dispersed by any method. However, dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate can be dispersed by a well-known emulsification dispersion method. And an auxiliary solvent such as ethyl acetate or cyclohexanone to dissolve and mechanically produce and use an emulsified dispersion. Alternatively, the powder of the antifoggant 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 average particle size of the antifoggant dispersion used in the present invention is 0.3 μm or less, preferably 0.1 μm or less.
01 to 0.3 μm, more preferably 0.05 to 0.3 μm.
0.25 μm. The maximum particle size is 2 μm or less, preferably 0.01 to 2 μm, and more preferably 0.05 to 1.5 μm. The particle size can be measured by any method, but can be measured by a laser diffraction / scattering type particle size distribution analyzer LA-910 manufactured by HORIBA.
In the present invention, as described above, it is important to control the average particle size and the maximum particle size of the antifoggant dispersion. In the emulsification dispersion method, the particle size can be controlled by the amount of a dispersant such as polyvinyl alcohol and the emulsification time. In order to obtain the fine particles of the present invention, it is effective to increase the amount of the dispersant and lengthen the emulsification time. However, when the amount of the dispersant is simply increased, the firing may become intense at the time of removing the organic solvent. It is effective to use. In the solid dispersion method, fine particles can generally be obtained by lengthening the dispersion time.

The type of the antifoggant used in the present invention is not particularly limited. Preferably, the compound of the general formula (I) or the general formula (II) or the compound of the general formula (II) is bonded through one carbon atom. Is a compound having a modified bisphenol structure. First, the compound of the general formula (I) that can be used in the present invention will be described.

[0013]

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In the general formula (I), Q is an alkyl group,
Represents an aryl group or a heterocyclic group. The aryl group represented by Q may be monocyclic or condensed, is preferably a monocyclic or bicyclic aryl group having 6 to 30 carbon atoms (eg, phenyl, naphthyl, etc.), and is more preferably phenyl. And a naphthyl group, and more preferably a phenyl group. The heterocyclic group represented by Q is a 3- to 10-membered saturated or unsaturated heterocyclic group containing at least one of N, O and S atoms, which may be monocyclic, It may form a condensed ring with another ring. The heterocyclic group is preferably a 5- or 6-membered unsaturated heterocyclic group optionally having a condensed ring, and more preferably a 5- or 6-membered aromatic heterocyclic ring optionally having a condensed ring. Group. More preferably, it is a 5- or 6-membered aromatic heterocyclic group containing a nitrogen atom.
And an aromatic heterocyclic group which may have a 5- or 6-membered condensed ring containing 4 to 4 atoms.

Specific examples of the heterocycle in the heterocyclic group include, for example, pyrrolidine, piperidine, piperazine, morpholine, thiophene, furan, pyrrole, imidazole, pyrazole, pyridine, pyrimidine, pyrazine, pyridazine, triazole, triazine, indole, Indazole, purine, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, thiazole, oxazole, benzimidazole, benzoxazole, benzothiazole, benzoselenazole, india Renin, tetrazaindene and the like. Preferably as a heterocycle, imidazole, pyrazole, pyridine, pyrimidine, pyrazine, pyridazine,
Triazole, triazine, indole, indazole, purine, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, thiazole,
Oxazole, benzimidazole, benzoxazole, benzthiazole, indolenine, tetrazaindene, more preferably imidazole, pyridine, pyrimidine, pyrazine, pyridazine, triazole, triazine, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline , Quinazoline, cinnoline, tetrazole, thiazole, oxazole, benzimidazole, benzoxazole, benzothiazole, tetrazaindene, more preferably imidazole, pyridine, pyrimidine, pyrazine,
Pyridazine, triazole, triazine, thiadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, tetrazole, thiazole, benzimidazole and benzthiazole, particularly preferably pyridine, thiadiazole, quinoline and benzthiazole.

The aryl group and heterocycle represented by Q may have a substituent in addition to-(Y) _m -CZ (X ₁ ) (X ₂ ). (Preferably having 1 to 20 carbon atoms, more preferably having 1 to 1 carbon atoms.
2, particularly preferably having 1 to 8 carbon atoms, for example, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, Cyclopropyl,
Cyclopentyl, cyclohexyl and the like can be mentioned. ), An alkenyl group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 12 carbon atoms, and particularly preferably having 2 carbon atoms.
-8, for example, vinyl, allyl, 2-butenyl, 3
-Pentenyl and the like. ), Alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, for example, propargyl,
Pentynyl and the like. ), An aryl group (preferably having 6 to 30 carbon atoms, more preferably having 6 to 20 carbon atoms, particularly preferably having 6 to 12 carbon atoms, for example, phenyl,
p-Methylphenyl, naphthyl and the like. ),
An amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms,
For example, amino, methylamino, dimethylamino, diethylamino, dibenzylamino and the like can be mentioned. ), An alkoxy group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 12 carbon atoms, particularly preferably having 1 to 8 carbon atoms, such as methoxy, ethoxy, and butoxy), and an aryloxy group ( Preferably 6 to 2 carbon atoms
It has 0, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples include phenyloxy and 2-naphthyloxy. ), An acyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, for example, acetyl,
Benzoyl, formyl, pivaloyl and the like can be mentioned. ), An alkoxycarbonyl group (preferably having 2 carbon atoms)
-20, more preferably 2-16 carbon atoms, particularly preferably 2-12 carbon atoms, for example, methoxycarbonyl,
Ethoxycarbonyl and the like. ), An aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, and particularly preferably having 7 to 1 carbon atoms.
0, for example, phenyloxycarbonyl and the like. ), An acyloxy group (preferably having 2 to 2 carbon atoms)
It has 0, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 10 carbon atoms, and examples thereof include acetoxy and benzoyloxy. ), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 16 carbon atoms, particularly preferably having 2 to 10 carbon atoms, and examples thereof include acetylamino and benzoylamino), and an alkoxycarbonylamino group. (Preferably having 2 to 20 carbon atoms,
More preferably, it has 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonylamino. ), An aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably having 7 carbon atoms)
To 16, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino. ), A sulfonylamino group (preferably having 1 to 2 carbon atoms)
0, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, for example, methanesulfonylamino,
Benzenesulfonylamino and the like. ), A sulfamoyl group (preferably having 0 to 20, more preferably 0 to 16, and particularly preferably 0 to 12 carbon atoms, for example, sulfamoyl, methylsulfamoyl,
Dimethylsulfamoyl, phenylsulfamoyl and the like can be mentioned. ), A carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include carbamoyl, methylcarbamoyl, diethylcarbamoyl, and phenylcarbamoyl). An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 1 carbon atoms)
6, particularly preferably 1 to 12 carbon atoms, for example, methylthio, ethylthio and the like. ), An arylthio group (preferably having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably having 6 to 12 carbon atoms, such as phenylthio, etc.), and a sulfonyl group (preferably having 1 carbon atom). ~ 20, more preferably 1 carbon atom
To 16, particularly preferably 1 to 12 carbon atoms, for example, mesyl, tosyl, phenylsulfonyl and the like. ), A sulfinyl group (preferably having 1 to 20 carbon atoms,
More preferably, it has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as methanesulfinyl and benzenesulfinyl. ), Ureido group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 1 carbon atoms)
6, particularly preferably 1 to 12 carbon atoms, for example, ureide, methylureide, phenylureide and the like. ), A phosphoric amide group (preferably having 1 to 2 carbon atoms)
It has 0, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include diethylphosphoramide and phenylphosphoramide. ), A hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom,
Chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, heterocyclic group (for example, imidazolyl, pyridyl, furyl, piperidyl, morpholino, etc.) )). These substituents may be further substituted. When there are two or more substituents, they may be the same or different.

The substituent is preferably an alkyl group, an alkenyl group, an aryl group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonyl. Amino group, sulfonylamino group, sulfamoyl group,
A carbamoyl group, a sulfonyl group, a ureido group, a phosphoric acid amide group, a halogen atom, a cyano group, a sulfo group, a carboxyl group, a nitro group, and a heterocyclic group, and more preferably an alkyl group, an aryl group, an alkoxy group, or an aryloxy group An acyl group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group,
Ureido group, phosphoric acid amide group, halogen atom, cyano group, nitro group, heterocyclic group, more preferably alkyl group, aryl group, alkoxy group, aryloxy group, acyl group, acylamino group, sulfonylamino group,
A sulfamoyl group, a carbamoyl group, a halogen atom, a cyano group, a nitro group, and a heterocyclic group, and particularly preferably an alkyl group, an aryl group, and a halogen atom.

The alkyl group represented by Q may be linear, branched or cyclic, and preferably has 1 to 30 carbon atoms, more preferably 1 to 15 carbon atoms. Examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and a tertiary octyl group. Alkyl group represented by Q _{- (Y) m -CZ (X} 1) (X 2) in addition to may have a substituent, the substituent, Q is a heterocyclic group or an aryl group, And the same substituents as possible in the case of are mentioned. As the substituent, preferably an alkenyl group, an aryl group, an alkoxy group, an aryloxy group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonylamino group, an alkylthio group, an arylthio group, a ureido group, and phosphorus Acid amide group, hydroxy group, halogen atom, heterocyclic group, more preferably aryl group, alkoxy group, aryloxy group, acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group, ureido group, A phosphoric amide group, a halogen atom, more preferably an aryl group, an alkoxy group, an aryloxy group,
An acylamino group, a sulfonylamino group, a ureido group, and a phosphoric amide group. These substituents may be further substituted. When there are two or more substituents, they may be the same or different.

Y is -C (= O)-, -SO- or -S
Represents O ₂ —, preferably —C (＝ O) —, —SO ₂ —, and more preferably —SO ₂ —. m represents 0 or 1, and is preferably 1. X ₁ and X ₂ each independently represent a halogen atom, and the halogen atoms represented by X ₁ and X ₂ may be the same or different from each other, and are preferably a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom; Is a chlorine atom, a bromine atom and an iodine atom, more preferably a chlorine atom and a bromine atom, and particularly preferably a bromine atom. Z represents a hydrogen atom or an electron-withdrawing group,
The electron-withdrawing group represented by Z is preferably a substituent having a Hammett's substituent constant σ _p value of 0.01 or more, more preferably 0.1 or more. For the Hammett's substituent constant, see Journal of Medicinal Chemistr.
y, 1973, Vol. 16, No. 11, 1207-1216, etc. can be referred to. Examples of the electron-withdrawing group include a halogen atom (fluorine atom (σp value: 0.06), a chlorine atom (σ
p value: 0.23), bromine atom (σp value: 0.23), iodine atom (σp value: 0.18), trihalomethyl group (tribromomethyl (σp value: 0.29), trichloromethyl ( σp value: 0.33), trifluoromethyl (σ
p value: 0.54)), a cyano group (σp value: 0.66),
Nitro group (σp value: 0.78), aliphatic / aryl or heterocyclic sulfonyl group (eg, methanesulfonyl (σp value: 0.72)), aliphatic / aryl or heterocyclic acyl group (eg, acetyl (σp Value: 0.5
0), benzoyl (σp value: 0.43)), alkynyl group (eg, C≡CH (σp value: 0.23)), aliphatic / aryl or heterocyclic oxycarbonyl group (eg, methoxycarbonyl (σp value: : 0.45), phenoxycarbonyl (σp value: 0.44)), carbamoyl group (σp value: 0.36), sulfamoyl group (σp value:
0.57).

Z is preferably an electron-withdrawing group, more preferably a halogen atom, an aliphatic / aryl or heterocyclic sulfonyl group, an aliphatic / aryl or heterocyclic acyl group, an aliphatic / aryl or heterocyclic oxycarbonyl. Group, carbamoyl group, sulfamoyl group,
Particularly preferred is a halogen atom. Among the halogen atoms, a chlorine atom, a bromine atom and an iodine atom are preferred, a chlorine atom and a bromine atom are more preferred, and a bromine atom is particularly preferred. Among the compounds represented by the general formula (I), a compound represented by the following general formula (Ia) is preferable.

[0021]

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In the formula, Q has the same meaning as in formula (I), and the preferred range is also the same. Further, the substituent that Q can take is the same as the substituent that Q can take in general formula (I). X ₁ , X ₂ , Y, and Z have the same meanings as those in formula (I), and the preferred ranges are also the same.

Among the compounds represented by the general formula (I), more preferred are the compounds represented by the general formula (Ib).

[0024]

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In the formula, Q has the same meaning as in formula (I), and the preferred range is also the same. Further, the substituent that Q can take is the same as the substituent that Q can take in general formula (I). X ₁ , X ₂ and Z have the same meanings as those in formula (I), and the preferred ranges are also the same. Specific examples of the compound represented by formula (I) are shown below, but the invention is not limited thereto.

[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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When Y = —SO— or —SO ₂ —, the compound represented by the general formula (I) used in the present invention is (1) aryl or heterocyclic mercaptan and α-halogenoacetic acid derivative, or α Α-arylthio or heterocyclic thioacetic acid derivative from a halogenoacetic acid ester derivative or the like, and (2) oxidation and bromination of the corresponding acetic acid derivative. In addition, Japanese Unexamined Patent Application Publication No.
A method for oxidizing and brominating a corresponding sulfide derivative as described in JP-A-304059 or the like;
A method of halogenating the corresponding sulfone derivative as described in 4754 and the like can also be used. α
Conversion to an arylthio or heterocyclic thioacetic acid derivative can be carried out by reacting the corresponding mercaptan compound with an α-halogenoacetic acid derivative or the like under basic conditions. Oxidation / halogenation of α-arylthio or heterocyclic thioacetic acid derivatives is described in, for example, U.S. Pat. Oxidation and halogenation can be performed simultaneously by adding and reacting an α-arylthio or heterocyclic thioacetic acid derivative or a salt thereof. Also, α
-It can also be synthesized by converting an arylthio or heterocyclic thioacetic acid derivative into a sulfoxide or a sulfonylacetic acid derivative in advance using an oxidizing agent such as hydrogen peroxide, and then halogenating the derivative.

As a method for synthesizing alkyl, aryl or heterocyclic mercaptans used as raw materials, for example, alkyl and aryl mercaptans are described in New Experimental Chemistry Course (Maruzen) 14-III, Chapter 8, 8-1, ORGANIC FUNCTIONA.
L GROUP PREPARATIONS (Sandler, Karo ACADEMIC PRESS
New York and Rondon) I-Chapt.18 or THE CHEMIST
RY OF FUNCTIONAL GROUPS (Patai, JONE WILLY &; SON
S) Various methods are known as described in "The Chemistry of the thiol group", Chapter 4. For heterocyclic mercaptans, Comprehensive Heterocyclic Che
mistry, Pergamaon Press, 1984 and Heterocyclic Compo
Various methods are known as described in unds, John Wiley and Sons, Vol. 1-9, 1950-1967 and the like.

When the compound represented by the general formula (I) used in the present invention is Y = -C (= O)-, (1) acetophenone or a carbonyl-substituted heterocyclic derivative is synthesized, and (2) It can be synthesized by α-halogenating a carbonyl compound. For the α-halogenation of a carbonyl compound, a method described in New Experimental Chemistry Course (Maruzen) 14-I, Chapter 2, etc. can be used. When m = 0, the compound can be synthesized by halogenating a heterocyclic compound having a toluene, xylene, or methyl group.
As a halogenation method, a method as described in New Experimental Chemistry Course (Maruzen) 14-I, Chapter 2, etc. can be used in the same manner as described above.

The compound of the general formula (I) used in the present invention may be added by a method of preparing a solid fine particle dispersion using a dispersant for the purpose of obtaining fine particles having a small particle size and without aggregation. The method of dispersing the compound of the general formula (I) into solid fine particles can be carried out by a known means for making fine particles in the presence of a dispersing agent (for example, ball mill, vibrating ball mill, planetary ball mill, sand mill, colloid mill, jet mill, roller mill) And can be dispersed mechanically. When the compound of the general formula (I) is formed into solid fine particles using a dispersant, for example, polyacrylic acid, a copolymer of acrylic acid,
Maleic acid copolymer, maleic acid monoester copolymer, acryloylmethylpropanesulfonic acid copolymer,
Synthetic anionic polymers such as carboxymethyl starch and carboxymethyl cellulose; anionic polymers such as alginic acid and pectic acid; and anionic surfactants described in JP-A-52-92716 and WO88 / 04794. The compounds described in Japanese Patent Application No. 7-350753, or known anionic, nonionic, cationic surfactants and other polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, etc. A polymer or a polymer compound existing in the natural world such as gelatin can be appropriately selected and used.

It is a general method that the dispersing aid is mixed with a powder of the compound of the general formula (I) or the compound of the general formula (I) in the form of a wet cake before dispersion and then sent to a dispersing machine as a slurry. Alternatively, a heat treatment or treatment with a solvent may be performed in a state where the compound is mixed with the compound of the general formula (I) in advance to obtain a powder or a wet cake. The pH may be controlled by a suitable pH adjuster before, during or after dispersion. 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. The prepared dispersion may be stored with stirring for the purpose of suppressing sedimentation of fine particles during storage, or may be stored in a highly viscous state by a hydrophilic colloid (for example,
(In a jelly state using gelatin). Further, a preservative can be added for the purpose of preventing the propagation of various bacteria during storage.

The compound of the general formula (I) is not limited to the addition position.
No image forming layer (photosensitive layer or heat sensitive layer), protective layer, etc.
Is added to the layer. The same layer as the layer containing organic silver salt or halo
It is particularly preferred that this is the same layer as the layer containing silver genide.
The compounds of the general formula (I) may be used alone or in combination of two or more.
May be. The compound of the general formula (I) has an image forming layer
1 × 10 per mole of silver^-6 Up to 0.5 mol
Preferably 1 × 10^-Five~ 1 × 10^-1Included
More preferably,

Next, the compound of the general formula (II) which can be used in the present invention and the compound having a bisphenol structure in which the compound of the general formula (II) is bonded via one carbon atom will be described in detail. The general formula (II) is shown below.

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In the general formula (II), M is a hydrogen atom or a k-valent cation (for example, sodium ion, potassium ion, calcium ion, barium ion, zinc ion, iron ion, manganese ion, cadmium ion, chromium ion, Metal ions such as cobalt ion, ruthenium ion, rhodium ion and silver ion, and ammonium ions such as tetramethylammonium ion and tetrabutylammonium ion). k is an integer of 1 or more as shown by the exemplified ion, and is usually 1 or 2. When M is a hydrogen atom, k = 1.
M is preferably a heavy metal ion, specifically, zinc, iron, manganese, cadmium, chromium, cobalt,
It is an ion such as ruthenium, rhodium, and silver. In the general formula (II), R represents a substituent, for example, a linear, branched or cyclic alkyl group (preferably having 1 to 20 carbon atoms,
More preferably 1 to 12, particularly preferably 1 to 8,
For example, methyl, ethyl, iso-propyl, t-butyl, n-octyl, 1,1,3,3-tetramethylbutyl, t-amyl, cyclohexyl and the like can be mentioned. ), An alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, for example, vinyl, allyl, 2-butenyl, 3-pentenyl and the like), alkynyl Group (preferably having 2 to 2 carbon atoms)
20, more preferably 2 to 12, particularly preferably 2 to 8, for example, propargyl, 3-pentynyl and the like. ), An aralkyl group (preferably having 7 to 30 carbon atoms,
It is more preferably from 7 to 20, particularly preferably from 7 to 16, and examples include benzyl, α-methylbenzyl, α-ethylbenzyl, diphenylmethyl, naphthylmethyl, naphthylphenylmethyl and the like. ), An aryl group (preferably having 6 to 30, more preferably 6 to 20, and particularly preferably 6 to 12; examples thereof include phenyl, p-methylphenyl, and naphthyl); and an amino group (preferably). Has 0 to 20, more preferably 0 to 10, and still more preferably 0 to 6 carbon atoms. Examples thereof include amino, methylamino, dimethylamino, diethylamino, dibenzylamino and the like, and an alkoxy group (preferably, It has from 1 to 20 carbon atoms, more preferably from 1 to 12, particularly preferably from 1 to 8, and includes, for example, methoxy, ethoxy, butoxy, etc., and an aryloxy group (preferably from 6 to 20, more preferably Is from 6 to 16, particularly preferably from 6 to 12, for example, phenyloxy, 2-naphthyloxy and the like.), An acyl group (preferably having 1 to 20 carbon atoms, Ri preferably 1 to 16, particularly preferably 1 to
12, for example, acetyl, benzoyl, formyl,
Pivaloyl and the like. ), An alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 1
6, particularly preferably 2 to 12, for example, methoxycarbonyl, ethoxycarbonyl and the like. ),
Aryloxycarbonyl group (preferably having 7 to 2 carbon atoms)
It is 0, more preferably 7 to 16, particularly preferably 7 to 10, and examples include phenoxycarbonyl. ), An acyloxy group (preferably having 1 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, such as acetoxy and benzoyloxy, etc.), and an acylamino group (preferably having 1 carbon atom). -20, more preferably 2-16, particularly preferably 2-10, for example, acetylamino, benzoylamino and the like.), Alkoxycarbonylamino group (preferably 2-20 carbon atoms, more preferably 2 carbon atoms) To 16, particularly preferably 2 to 12, for example, methoxycarbonylamino and the like.), An aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably having 7 to 16 carbon atoms). 12, for example, phenyloxycarbonylamino and the like), a sulfonylamino group (preferably having 1 to 20 carbon atoms, Ri is preferably 1 to 1
6, particularly preferably 1 to 12, for example, methanesulfonylamino, benzenesulfonylamino and the like. ), A sulfamoyl group (preferably having 0 to 2 carbon atoms)
0, more preferably 0 to 16, particularly preferably 0 to 12, for example, sulfamoyl, methylsulfamoyl,
Dimethylsulfamoyl, phenylsulfamoyl and the like can be mentioned. ), A carbamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 16, particularly preferably 0 to 12 carbon atoms).
And examples thereof include carbamoyl, diethylcarbamoyl, phenylcarbamoyl and the like. ), Ureido group (preferably 1 to 20 carbon atoms, more preferably 1 to
16, particularly preferably 1 to 12, for example, ureido,
Methyl ureide, phenyl ureide and the like can be mentioned. ), An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16, particularly preferably 1 to 12, and examples thereof include methylthio and ethylthio).
An arylthio group (preferably having 6 to 20, more preferably 6 to 16, particularly preferably 6 to 12, and examples thereof include phenylthio, etc.) and a sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably Is 1 to 16, particularly preferably 1 to 12, and examples thereof include mesyl and tosyl.), A sulfinyl group (preferably having 1 to 1 carbon atoms)
20, more preferably 1 to 16, particularly preferably 1 to 12, for example, methanesulfinyl, benzenesulfinyl and the like. ), A phosphoramide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 16 carbon atoms).
To 12, for example, diethylphosphoramide, phenylphosphoramide and the like. ), Hydroxy, mercapto, halogen (eg, fluorine, chlorine, bromine, iodine), cyano, sulfo, carboxy, nitro, hydroxam, sulfino, sulfino, hydrazino, sulfonylthio Thiosulfonyl group, heterocyclic group (for example, imidazolyl, pyridyl, furyl, piperidyl, morpholinyl, etc.),
And a disulfide group.

These substituents may be further substituted and may form a salt if the group is capable of forming a salt. In addition, n is an integer of 0 to 4, but when there are two or more substituents, that is, when n ≧ 2, they may be the same or different. n is preferably 1 to 3, and most preferably 2. These substituents may be bonded to each other to form a 5- to 7-membered non-aromatic or aromatic carbon ring (for example, a benzene ring). Further, this ring may be substituted with another substituent (eg, a halogen atom, a carboxy group). The substituent represented by R is preferably an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, an amino group, an alkoxy group, an acyl group,
Alkoxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, ureido group, alkylthio group, sulfonyl group, hydroxy group, mercapto group, halogen atom, cyano group, sulfo group, carboxy Group, a nitro group, a heterocyclic group, more preferably an alkyl group, an alkenyl group, an aralkyl group, an amino group, an alkoxy group, an alkylthio group, a hydroxy group,
A mercapto group, a halogen atom, a sulfo group, and a carboxy group.

Further, in the general formula (II), it is particularly preferable that the hydroxyl group is substituted with an alkyl group at the ortho position and / or the para position. Further, a bisphenol structure in which the compound of the general formula (II) is bonded via one carbon is more preferable. In this case, one carbon atom linking the compound of the general formula (II) is a substituted or unsubstituted methylene group. The number of substituents on the methylene group is 1 or 2, and examples of the substituent include an alkyl group (for example, an alkyl group having 1 to 6 carbon atoms), an aryl group (for example, a phenyl group, a naphthyl group, and the like). These substituents may be further substituted with a substituent such as an alkyl group, a halogen atom (such as a chlorine atom), a hydroxyl group, a nitro group or a carboxyl group. Next, specific examples of the compound of the general formula (II) and the compound having a bisphenol structure in which the compound of the general formula (II) is bonded through one carbon atom are shown, but the present invention is not limited thereto.

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As the compound of the general formula (II), a commercially available compound may be used. Can be easily synthesized by an acid-catalyzed condensation reaction of salicylic acid with a carbonyl compound. The photothermographic image-forming material of the present invention preferably contains a super-high contrast agent. The kind of the super-high contrast agent used in the present invention is not particularly limited, but preferably,
Substituted alkene derivatives, substituted isoxazole derivatives, and specific acetal compounds represented by the general formulas (III), (IV), and (V) are used.

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In the general formula (III), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group. In the general formula (III), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure. In the general formula (IV), R
⁴ represents a substituent. In the general formula (V), 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. , A heterocyclic oxy group, a heterocyclic thio group, or a heterocyclic amino group. In the general formula (V), X and Y or A and B may be bonded to each other to form a cyclic structure. When R ¹ , R ² and R ³ represent a substituent in the general formula (III), examples of the substituent include a halogen atom (a fluorine atom, a chloro atom, a bromine atom or an iodine atom) and an alkyl group (Including aralkyl groups, cycloalkyl groups, active methine groups, etc.), alkenyl groups, alkynyl groups, aryl groups, heterocyclic groups (including N-substituted nitrogen-containing heterocyclic groups) and quaternized nitrogen atoms A heterocyclic group (eg, a pyridinio group), an acyl group, an alkoxycarbonyl group,
An aryloxycarbonyl group, a carbamoyl group, a carboxy group or a salt thereof, an imino group, an imino group substituted with an N atom, a thiocarbonyl group, a sulfonylcarbamoyl group,
Acylcarbamoyl group, sulfamoylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group,
Cyano group, thiocarbamoyl group, hydroxy group, alkoxy group (including groups containing repeating ethyleneoxy or propyleneoxy group units), aryloxy group, heterocyclic oxy group, acyloxy group, (alkoxy or aryloxy) carbonyloxy group , Carbamoyloxy group, sulfonyloxy group, amino group, (alkyl, aryl, or heterocycle) amino group, acylamino group, sulfonamide group, ureido group, thioureido group, isothioureido group, imide group, (alkoxy or aryloxy) carbonyl Amino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, quaternary ammonio group, oxamoylamino group, (alkyl or aryl) sulfonyluureido group, acyluree Group, acylsulfamoylamino group, nitro group, mercapto group, (alkyl, aryl, or heterocycle) thio group, acylthio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or A salt thereof, a sulfamoyl group, an acylsulfamoyl group, a sulfonylsulfamoyl group or a salt thereof, a phosphoryl group, a group containing a phosphate amide or phosphate ester structure, a silyl group,
And a stannyl group. These substituents may be further substituted with these substituents.

The electron-withdrawing group represented by Z in the general formula (III) is a substituent whose Hammett's substituent constant σ _p can take a positive value. Group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted by N atom,
Thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, halogen atom, perfluoroalkyl group, perfluoroalkaneamide group, sulfonamide group, acyl group, formyl group, phosphoryl group, carboxy group, sulfo group (Or a salt thereof), a heterocyclic group, an alkenyl group, an alkynyl group, an acyloxy group, an acylthio group, a sulfonyloxy group, or an aryl group substituted with these electron-withdrawing groups. Here, the heterocyclic group is an aromatic or non-aromatic, saturated or unsaturated heterocyclic group, for example, a pyridyl group, a quinolyl group, a pyrazinyl group, a benzotriazolyl group, an imidazolyl group, a benzimidazolyl group, a hydantoin group. Examples thereof include a 1-yl group, a urazol-1-yl group, a succinimide group, and a phthalimide group. The electron-withdrawing group represented by Z in the general formula (III) may further have an optional substituent. General formula (I
In II), the electron-withdrawing group represented by Z is preferably a group having a total carbon number of 0 to 30 or less, that is, a cyano group,
Alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, thiocarbonyl group, imino group, N
Substituted with an atom-substituted imino group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group, acyloxy group, acylthio group, or any electron-withdrawing group And further preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, a thiocarbonyl group, an imino group, an imino group substituted with an N atom, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, an acyl group , A formyl group, a phosphoryl group, a trifluoromethyl group, or a phenyl group substituted with an arbitrary electron-withdrawing group, and particularly preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, an imino group, and a group substituted with an N atom. Imino group, alkylsulfonyl group, ant Rusuruhoniru group, an acyl group, or a formyl group,.

The substituent represented by R ¹ in the general formula (III) is preferably a group having a total carbon number of 0 to 30, specifically, represented by Z in the general formula (III). A group having the same meaning as the electron-withdrawing group, and an alkyl group, an alkenyl group, an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, an amino group,
An alkylamino group, an arylamino group, a heterocyclic amino group, a ureido group, an acylamino group, a silyl group, or a substituted or unsubstituted aryl group, more preferably an electron represented by Z in the above general formula (III) Group having the same meaning as the attraction group, substituted or unsubstituted aryl group, alkenyl group, alkylthio group, arylthio group, alkoxy group,
A silyl group or an acylamino group, more preferably an electron-withdrawing group, an aryl group, an alkenyl group, or an acylamino group. When R ¹ represents an electron-withdrawing group, its preferred range is the same as the preferred range of the electron-withdrawing group represented by Z.

The substituent represented by R ² and R ³ in the general formula (III) is preferably Z
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. R2 and R3 are more preferably when one of them is a hydrogen atom and the other represents a substituent. The substituent is preferably 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, a heterocyclic thio group, an amino group. 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, and 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, an amino group, or a heterocyclic group, and particularly preferably. It is a hydroxy group (or a salt thereof), an alkoxy group, or a heterocyclic group.

In the general formula (III), it is also preferable that Z and R ¹ , or R ² and R ³ form a cyclic structure.
The cyclic structure formed in this case is a non-aromatic carbon ring or a non-aromatic hetero ring, and preferably has 5 to 7 members.
Having a total carbon number of 1 to 4 including substituents.
0, more preferably 3 to 35. Among the compounds represented by formula (III), more One of preferred, Z represents a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, an imino group or a carbamoyl group,, R ¹ is an electron withdrawing One of R ^{2 and} R ³ 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. A compound representing a group, an arylthio group, a heterocyclic thio group, an amino group or a heterocyclic group Furthermore, one of the more preferable compounds represented by the general formula (III) is that Z and R ¹ are linked to form a non-aromatic 5- to 7-membered cyclic structure, Either ² or R ³ 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, an amino group, or a heterocyclic group. Here, the non-aromatic 5- to 7-membered cyclic structure formed by Z and R ¹ is specifically an indane-1,3-dione ring, a pyrrolidine-2,4-dione ring, a pyrazolidine-
3,5-dione ring, oxazolidine-2,4-dione ring, 5-pyrazolone ring, imidazolidine-2,4-dione ring, thiazolidine-2,4-dione ring, oxolane-
2,4-dione ring, thiolan-2,4-dione ring, 1,
3-dioxane-4,6-dione ring, cyclohexane-
1,3-dione ring, 1,2,3,4-tetrahydroquinoline-2,4-dione ring, cyclopentane-1,3-dione ring, isoxazolidine-3,5-dione ring, barbituric acid ring, 2,3-dihydrobenzofuran-3-one ring, pyrazolotriazole ring (for example, 7H-pyrazolo [1,5-b] [1,2,4] triazole, 7H-pyrazolo [5,1-c] [1, 2,4] triazole, 7
H-pyrazolo [1,5-a] benzimidazole and the like),
Pyrrolotriazole ring (for example, 5H-pyrrolo [1,2-
b] [1,2,4] triazole, 5H-pyrrolo [2,
1-c] [1,2,4] triazole, etc.), 2-cyclopentene-1,3-dione ring, 2,3-dihydrobenzothiophen-3-one-1,1-dioxide ring, chroman-2,4 -Dione ring, oxazoline-5-one ring and the like, among which indane-1,3-dione ring, pyrrolidine-2,4-dione ring, pyrazolidine-3,5-dione ring, 5-pyrazolone ring, barbitur Acid rings and oxazolin-5-one rings are preferred.

Examples of the substituent represented by R ⁴ in the general formula (IV) are the same as those described for the substituents R ^{1 to} R ^{3 in} the general formula (III). The substituent represented by R ⁴ in the general formula (IV) is preferably an electron-withdrawing group or an aryl group. When R ⁴ represents an electron-withdrawing group, preferably the following groups having a total carbon number of 0 to 30, ie,
Cyano group, nitro group, acyl group, formyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, carbamoyl group, sulfamoyl group, perfluoroalkyl group, phosphoryl group, imino group, sulfonamide group, Or a heterocyclic group, and further a cyano group, an acyl group, a formyl group,
Preferred are an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, a sulfonamide group, and a heterocyclic group. When R ⁴ represents an aryl group, it preferably has a total of 0 to 30 carbon atoms,
It is a substituted or unsubstituted phenyl group, and examples of the substituent include the same as those described as the substituent when R ¹ , R ² , and R ^{3 in} the general formula (III) represent the substituent. Electron withdrawing groups are preferred.

The substitution represented by X and Y in the general formula (V)
As the group, R of the general formula (III)¹~ R^Three About the substituents
The same ones as described are mentioned. Represented by X, Y
Substituents are preferably 1 to 50 carbon atoms in total, more preferably
It is preferably a group having a total carbon number of 1 to 35, a cyano group, an a
Alkoxycarbonyl group, aryloxycarbonyl group,
Carbamoyl group, imino group, imino substituted with N atom
Group, thiocarbonyl group, sulfamoyl group, alkyls
Ruphonyl group, arylsulfonyl group, nitro group, perf
Fluoroalkyl group, acyl group, formyl group, phosphoryl
Group, acylamino group, acyloxy group, acylthio group,
A heterocyclic group, an alkylthio group, an alkoxy group, or an
Reel bases and the like are preferred. More preferably a cyano group, nitro
B, alkoxycarbonyl group, carbamoyl group, reed
Group, formyl group, acylthio group, acylamino group,
Ocarbonyl group, sulfamoyl group, alkylsulfoni
Group, arylsulfonyl group, imino group, substituted with N atom
Imino group, phosphoryl group, trifluoromethyl group,
A heterocyclic group or a substituted phenyl group;
Is preferably a cyano group, an alkoxycarbonyl group,
Bamoyl group, alkylsulfonyl group, arylsulfoni
Group, acyl group, acylthio group, acylamino group, thio
Substituted with a carbonyl, formyl, imino or N atom
Imino group, heterocyclic group, or any electron-withdrawing group
And a substituted phenyl group.

It is also preferred that X and Y combine with each other to form a non-aromatic carbon ring or a non-aromatic hetero ring. The ring formed at this time is preferably a 5- to 7-membered ring, and specifically, a non-aromatic 5- to 7-membered ring which can be formed by bonding Z and R ¹ of the general formula (III) to each other. And the preferred range is also the same. These rings may further have a substituent, and the total carbon number is preferably 1 to 40, more preferably 1 to 35. General formula
The group represented by A or B in (V) may further have a substituent, and is preferably a group having a total carbon number of 1 to 40, more preferably a group having a total carbon number of 1 to 30. . General formula
In (V), 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 connected (-AB-)
By way of, 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 -} , - O- (CH 2) 3 -S -, - N
(CH ₃ ) -ph-S-, -N (ph)-(CH ₂ ) _2-
S- and so on.

The compounds represented by the general formulas (III) to (V) may have incorporated therein an adsorptive group which adsorbs to silver halide. Ballast groups or polymers commonly used in immobile photographic additives such as couplers may be incorporated, and cationic groups (specifically, groups containing a quaternary ammonium group, or A nitrogen-containing heterocyclic group containing a graded nitrogen atom), a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, an (alkyl, aryl, or heterocyclic) thio group,
Alternatively, it may contain a dissociable group (such as a carboxy group, a sulfo group, an acylsulfamoyl group, or a carbamoylsulfamoyl group) that can be dissociated by a base. Examples of these groups include, for example, JP-A-63-29751, U.S. Pat. Nos. 4,385,108 and 4,459,347.
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
JP-A-3-234246, JP-A-2-285344, JP-A-1-100530, JP-A-7-234471, JP-A-5-333466, JP-A-6-19032, JP-A-6-19031, JP-A-5 No. 4,5761,365, U.S. Pat. No. 4,994,365, U.S. Pat. No. 4,988,604, JP-A-73-259240, JP-A-7-5610, JP-A-7-244348, and German Patent 4006032. Specific examples of the compounds represented by the general formulas (III) to (V) are shown below. However, the present invention is not limited to the following compounds.

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The compounds represented by the general formulas (III) to (V) can be easily synthesized by a known method. For example, US Pat.
No. 39, US Pat. No. 5,654,130, International Publication WO97
/ 34196, or Japanese Patent Application Nos. 9-354107, 9-309813, and 9-272002. General formula (II
The compounds represented by (I) to (V) 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.
9, U.S. Pat. No. 5,654,130, U.S. Pat.
No. 24, the compound described in U.S. Pat.
3935, Japanese Patent Application No. 9-354107, Japanese Patent Application No. 9-3
No. 09813, Japanese Patent Application No. 9-296174, Japanese Patent Application No. 9-296
No. 282564, Japanese Patent Application No. 9-272002, Japanese Patent Application No. 9
-272003 and Japanese Patent Application No. 9-332388 may be used in combination. Further, in the present invention, various hydrazine derivatives described in JP-A-10-161270 can be used in combination.

The compounds represented by the general formulas (III) to (V) can be prepared by using water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol) and ketones (acetone, methyl ethyl ketone). ,
It can be used by dissolving in dimethylformamide, dimethylsulfoxide, methylcellosolve and the like. Also,
By an already well-known emulsification dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate is dissolved using an auxiliary solvent such as ethyl acetate or cyclohexanone, and the emulsified dispersion is mechanically dispersed. It can be manufactured and used. Alternatively, by a method known as a solid dispersion method, a powder of a compound represented by the general formula (III) to the general formula (V) is dispersed in a suitable solvent such as water by a ball mill, a colloid mill, or ultrasonic waves. Can be used. The compounds represented by the general formulas (III) to (V) may be added to the image recording layer or any other layer on the image recording layer side with respect to the support. It is preferable to add it to the layer adjacent thereto. General formula (III)-
The addition amount of the compound represented by the general formula (V) is preferably 1 × 10 ⁻⁶ to 1 mol per 1 mol of silver, and 1 × 10 ^{−5 to} 5 × 1.
0 ^-1 mol is more preferred, and 2 × 10 ^-5 to 2 × 10 ^-1 mol 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 above-mentioned super-high contrast agent. For example, the amine compounds described in U.S. Patent No. 5,545,505, specifically AM-1 to AM-5, and 5,545,507
The hydroxamic acids, specifically HA-1 to HA-1
1, acrylonitriles described in 5,545,507, specifically CN-1 to CN-13, hydrazine compounds described in 5,558,983, specifically CA-1 to CA-6, JP-A-9-2973
68. Onium salts according to 68, specifically A-1 to A-4
2, 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 super-high contrast agents and high-contrast accelerators can be performed as described in each of the cited patents.

Next, the photosensitive silver halide used in the present invention will be described in detail. The photosensitive silver halide used in the present invention is not particularly limited as a halogen composition,
Silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide can be used. The distribution of the halogen composition in the grains may be uniform, the halogen composition may change stepwise, or may change continuously. Further, silver halide grains having a core / shell structure can be preferably used. As the structure, core / shell particles having preferably a 2- to 5-layer structure, more preferably a 2- to 4-layer structure, can be used. A technique for localizing silver bromide on the surface of silver chloride or silver chlorobromide grains can also be preferably used. The method of forming the photosensitive silver halide in the present invention is well known in the art, for example, Research Disclosure No. 17029 of June 1978.
And the methods described in U.S. Pat. No. 3,700,458. Specific methods that can be used in the present invention include a method of converting a part of the silver of the organic silver salt to a photosensitive silver halide by adding a halogen-containing compound to the prepared organic silver salt, gelatin. Alternatively, a method of preparing a photosensitive silver halide grain by adding a silver supply compound and a halogen supply compound to another polymer solution and mixing the resultant with an organic silver salt can be used. In the present invention, the latter method can be preferably used. The grain size of the photosensitive silver halide is preferably small for the purpose of suppressing the white turbidity after image formation, specifically, 0.20 μm or less, more preferably 0.01 μm or less.
0.15μm or less, more preferably 0.02μm or more 0.12μ
m or less is good. Here, the grain size means the length of the edge of the silver halide grain when the silver halide grain is a cubic or octahedral so-called normal crystal. In the case where the silver halide grains are tabular grains, the diameter refers to a diameter when converted into a circular image having the same area as the projected area of the main surface. In the case of other than normal crystals, for example, in the case of spherical grains, rod-like grains, etc., it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

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.

The photosensitive silver halide grains used in the present invention
Are metals or metals of group VII or VIII of the periodic table
Preferably contains a metal complex. VI of the Periodic Table
Central metal of Group I or VIII metals or metal complexes
Is preferably rhodium, rhenium, ruthenium,
They are sunium and iridium. One of these metal complexes
Or two or more complexes of the same and different metals.
May be used. The preferred content is 10 moles per mole of silver.^-9
10 from mole^-2The molar range is preferably 10^-8 From mole
10^-FourA molar range is more preferred. Specific metal complex
As the structure, gold having the structure described in JP-A-7-225449
A genus complex can be used. Preferably used in the present invention
Examples of the rhodium compound include a water-soluble rhodium compound.
Can be used. For example, rhodium halide
(III) Compound or rhodium complex as ligand
Those having a logene, amines, oxalato, etc.
For example, hexachlororhodium (III) complex salt, pentachloro
Achodium (III) complex salt, tetrachlorodiachodium
(III) complex salt, hexabromorhodium (III) complex salt,
Oxaminmine rhodium (III) complex salt, Trizaratrodiu
(III) complex salts. These rhodium compounds
The substance is used after being dissolved in water or a suitable solvent.
Generally well used to stabilize solutions of rhodium compounds
The method to be performed, ie, the aqueous solution of hydrogen halide (
For example, hydrochloric acid, bromic acid, hydrofluoric acid, etc.)
Those who add potassium (eg KCl, NaCl, KBr, NaBr, etc.)
Method can be used. An alternative to using water-soluble rhodium
When preparing silver halide, rhodium is
Add and dissolve another silver halide grain
It is also possible.

The addition amount of these rhodium compounds is
1 × 10 per mole of silver halide^-8Mol to 5 × 10^-6Molar range
Enclosure is preferable, and particularly preferably 5 × 10^-8Mol ~ 1 x 1
0^-6 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 when the emulsion is formed.
And preferably incorporated into silver halide grains.
No. Rhenium and ruthenium preferably used in the present invention
And osmium are disclosed in JP-A-63-2042 and JP-A-1-285941
No. 2-20852, water-soluble complex salts described in 2-20855, etc.
It is added in the form of Particularly preferred are the following formulas
And a six-coordinate complex represented by [ML₆]^-n  Here, M represents Ru, Re, or Os, and L represents a ligand.
And n represents 0, 1, 2, 3 or 4. This place
If the counterion is not important, ammonium or
Alkali metal ions are used. Also preferred ligand
As halide ligand, cyanide ligand,
Oxide ligand, nitrosyl ligand, thionitrosyl ligand
And the like. Hereinafter, specific examples used in the present invention
Examples of complexes are shown, but the present invention is not limited to these.
Absent.

[ReCl₆]^-3 [ReBr₆]^-3 [ReCl_Five(NO)]^-2  [Re (NS) Br_Five]^-2[Re (NO) (CN)_Five]^-2 [Re (O)_Two(CN)_Four]^-3  [RuCl₆]^-3 [RuCl_Four(H_TwoO)_Two]^-1 [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 ⁻⁵ mol per mol, and particularly preferably from 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁶ 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 to incorporate them into the silver halide grains. . In order to add these compounds during silver halide grain formation and incorporate them into silver halide grains, powder of metal complex or Na
A method in which an aqueous solution dissolved together with Cl and KCl is added to a water-soluble salt or water-soluble halide solution during particle formation,
Alternatively, when a silver salt and a halide solution are simultaneously mixed, they are added as a third solution to prepare silver halide grains by a three-solution simultaneous mixing method, or a required amount of an aqueous solution of a metal complex is reacted during grain formation. There is a method of putting it in a container. 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.

Various compounds can be used as the iridium compound preferably used in the present invention, 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 to stabilize the solution of the iridium compound, that is, a hydrogen halide aqueous solution (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) is used. Etc.) or alkali halides (eg KCl, NaCl, KBr, NaBr
Etc.) can be used. 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, cobalt, iron, nickel, chromium, palladium, platinum, gold, thallium, copper,
It may contain a metal atom such as lead. For compounds of cobalt, iron, chromium, and ruthenium, hexacyano metal complexes 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, in order to incorporate the metal, a metal salt in the form of a single salt, a double salt, or a complex salt can be added at the time of preparing particles.

The photosensitive silver halide grains can be desalted by washing with water by 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 chemically sensitized. As the method of chemical sensitization, 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, and these are used alone or in combination. When used in combination, for example, sulfur sensitization and gold sensitization, sulfur sensitization and selenium sensitization and gold sensitization, sulfur sensitization and tellurium sensitization and gold sensitization, Sulfur sensitization, selenium sensitization, tellurium sensitization, gold sensitization and the like are preferred. The sulfur sensitization 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 period of time. Known compounds can be used as the sulfur sensitizer. For example, in addition to sulfur compounds contained in gelatin, various sulfur compounds such as thiosulfates, thioureas, thiazoles, rhodanines and the like are used. be able to. Preferred sulfur compounds are thiosulfates and thiourea compounds. The amount of the sulfur sensitizer to be added depends on the pH during chemical ripening,
Temperature, varies under various conditions such as the size of the silver halide grains, per mol of silver halide 10 ^-7 to 10 ^-2
Mol, more preferably 10 ^-5 to 10 ^-3 mol.

As the selenium sensitizer used in the present invention, known selenium compounds can be used. That is, it is usually carried out by adding an unstable and / or non-unstable selenium compound and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. As unstable selenium compounds, JP-B-44-15748, JP-B-43-13489, JP-A-4-25832,
The compounds described in JP-A Nos. 4-109240, 3-21798 and the like can be used. In particular, it is preferable to use compounds represented by formulas (VIII) and (IX) in JP-A-4-324855. The tellurium sensitizer used in the present invention is a compound that 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-5-31.
It can be tested by the method described in No. 3284. 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,
Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Specifically, U.S. Pat.Nos. 1,623,499 and 3,320,06
No. 9, 3,772,031, British Patent No. 235,211 and No. 1,121,
No. 496, No. 1,295,462, No. 1,396,696, Canadian Patent No. 800,958, Japanese Patent Application No. 2-333819, No. 3-53693, No. 3-13159
No. 8, No. 4-129787, Journal of Chemical Society Chemical Communication (J. Chem. S.
oc.Chem.Commun.) 635 (1980), ibid 1102 (1979), ibid 6
45 (1979), Journal of Chemical Society Perkin Transaction (J. Chem. Soc. Perkin.
Trans.) 1,2191 (1980), edited by S. Patai, edited by The Chemistry of Organ, Selenium and Tellurium
ic Serenium and Tellunium Compounds), Vol 1 (1986),
The compounds described in Vol. 2 (1987) can be used.
In particular, JP-A-5-313284 discloses general formulas (II) and (II).
The compounds represented by I) and (IV) are preferred.

The amount of the selenium and tellurium sensitizers used in the present invention varies depending on the silver halide grains to be used, the conditions of chemical ripening, etc., but generally 10 ^-8 to 10 ^-2 mol per mol of silver halide, 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. Examples of the noble metal sensitizer used in the present invention include gold, platinum, palladium, and iridium, and gold sensitization is particularly preferable. Specific examples of the gold sensitizer used in the present invention include chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, and gold sulfide, and 10 ^-7 to 10 ^-2 mol per mol of silver halide. Degrees can be used. 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. . Further, the pH of the emulsion is 7 or more or the pAg is 8.
Reduction sensitization can be achieved by ripening while keeping at 3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ion during grain formation. To the silver halide emulsion used in the present invention, a thiosulfonic acid compound may be added according to the method described in EP 293,917. The silver halide emulsion used in the present invention may be only one kind, or two or more kinds (e.g., 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 per 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 image-forming material of the present invention contains a non-photosensitive reducible organic silver salt. The organic silver salt that can be used in the present invention is relatively stable to light, but at 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of a photosensitive silver halide) and a reducing agent. It is a silver salt that forms a silver image when heated as described above. 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 the aliphatic carboxylic acid include silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate, and fumarate. Silver acid, silver tartrate, silver linoleate, silver butyrate and silver camphorate, and mixtures thereof. Silver salts of compounds containing a mercapto group or a thione group and derivatives thereof can also be used. Preferred examples of these compounds include silver salt of 3-mercapto-4-phenyl-1,2,4-triazole, silver salt of 2-mercaptobenzimidazole, and 2-mercapto-5-
Silver salts of thioglycolic acid such as silver salts of aminothiadiazole, silver salts of 2- (ethylglycolamide) benzothiazole, silver salts of S-alkylthioglycolic acid (where the alkyl group has 12 to 22 carbon atoms) , Silver salts of dithiocarboxylic acids such as silver salts of dithioacetic acid, silver salts of thioamides, silver salts of 5-carboxyl-1-methyl-2-phenyl-4-thiopyridine, silver salts of mercaptotriazine, 2-mercaptobenzoxazole Silver salts described in U.S. Pat.No. 4,123,274, for example, silver salts of 1,2,4-mercaptothiazole derivatives such as silver salts of 3-amino-5-benzylthio-1,2,4-thiazole, U.S. Pat. And silver salts of thione compounds such as silver salt of 3- (3-carboxyethyl) -4-methyl-4-thiazoline-2-thione described in Japanese Patent No. 3,301,678. Furthermore, compounds containing an imino group can also be used. Preferred examples of these compounds include silver salts of benzotriazole and derivatives thereof, for example, silver salts of benzotriazole such as silver methylbenzotriazole, silver salts of halogen-substituted benzotriazole such as silver 5-chlorobenzotriazole, and US Pat. No. 4,220,709, silver salts of 1,2,4-triazole or 1-H-tetrazole, and silver salts of imidazole and imidazole derivatives. For example, U.S. Pat.
Various silver acetylide compounds as described in 1,361 and 4,775,613 can also be used.

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 100% or less, more preferably 80% or less,
More preferably, it is 50% or less. 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, 100% of the value divided by the volume-weighted average diameter (coefficient of variation) is preferably 100% or less , More preferably 80% or less,
More preferably, it is 50% or less. As a measuring method, for example, a particle size (volume weight average diameter) obtained by irradiating a laser beam to an organic silver salt dispersed in a liquid and obtaining an autocorrelation function for a time change of fluctuation of the scattered light.
Can be obtained from The organic silver salt that can be used in the present invention is preferably desalted. 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, and floc-forming water washing by a coagulation method can be preferably used. .

In the present invention, in order to obtain an organic silver salt solid dispersion having a high S / N, a small particle size and no aggregation, an organic silver salt which is an image forming medium and a photosensitive silver salt are substantially contained. It is preferable to use a dispersion method in which a water dispersion liquid which is not included in the liquid is converted into a high-speed flow 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 high-pressure, the aqueous dispersion is dispersed and converted to high speed, is substantially free of photosensitive silver salt, the water content is 0.1 mol% based on the non-photosensitive organic silver salt The following is the case where the photosensitive silver salt is not positively added.

In the present invention, the solid dispersion apparatus and the technique used for carrying out the dispersion method as described above are described in, for example, “Dispersion Rheology and Dispersion Technology” (Toshio Kajiuchi and Hiroki Usui, 1991, Shinzansha Publishing Co., Ltd., p357
-P403), "The 24th Progress of Chemical Engineering", edited by The Society of Chemical Engineers, Tokai Branch, 1990, Maki Shoten, p184-p185),
Although detailed in the dispersing method of the present invention, the aqueous dispersion containing at least an organic silver salt is pressurized by a high-pressure pump or the like and sent into a pipe, and then passed through a narrow slit provided in the pipe, Thereafter, the dispersion is finely dispersed by causing an abrupt 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.).

As a dispersing apparatus suitable for the present invention, a microfluidizer M-110S-EH manufactured by Microfluidics International Corporation is used.
(With G10Z interaction chamber), M-
110Y (with H10Z interaction chamber), M-140K (with G10Z interaction chamber), HC-5000 (L30Z or H23
With 0Z interaction chamber), HC-80
00 (with an E230Z or L30Z interaction chamber) and the like. Using these devices,
After the aqueous dispersion containing at least the organic silver salt is pressurized by a high-pressure pump or the like and sent into the pipe, a desired pressure is applied by passing through a narrow slit provided in the pipe, and thereafter, the inside of the pipe is It is possible to obtain an optimal organic silver salt dispersion for the present invention by causing a rapid pressure drop in the dispersion by, for example, rapidly returning the pressure to the atmospheric pressure. In organic silver salt dispersion, it is possible to disperse to 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 ～600M / sec, preferably in the range differential pressure of 900~3000kg / cm ² at the time of pressure drop, the range the flow rate is 300 meters / sec ～600M / sec, the pressure difference at the pressure drop of 1500~3000kg / cm ² Is more preferable. 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. It is not preferable to raise the temperature of such an aqueous dispersion under high pressure from the viewpoint of dispersibility and photographic characteristics.At a temperature higher than 90 ° C., the particle size tends to increase, and the fog tends to increase. is there. 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, it is preferable to disperse the organic silver salt 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.

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 aid. 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. Organic silver salts can be used in a desired amount, preferably 0.1-5 g / m ² as silver amount, more preferably from 1 to 3 g / m ^2.

The photothermographic image-forming material of the present invention 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 used in an amount of 5 to 50 mol based on 1 mol of silver on the surface having the image forming layer.
%, More preferably 10 to 40 mol%. 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, 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. 86, No. 3,679,426, No. 3,751,252, No. 3,751,255
Nos. 3,761,270, 3,782,949, 3,839,048,
3,928,686, 5,464,738, German patent 2321328,
It is disclosed in European Patent No. 692732 and the like. For example, phenylamide oxime, 2-thienylamide oxime and
Amide oximes such as p-phenoxyphenylamide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; combinations of 2,2′-bis (hydroxymethyl) propionyl-β-phenylhydrazine with ascorbic acid A combination of such an aliphatic carboxylic acid aryl hydrazide and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (eg, hydroquinone and bis (ethoxyethyl) hydroxylamine, piperidinohexose reductone Or a combination of formyl-4-methylphenylhydrazine, etc.); phenylhydroxamic acid, p
Hydroxamic acids such as -hydroxyphenylhydroxamic acid and β-alinine hydroxamic acid; combinations of azines with sulfonamidophenols (eg, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol); ethyl-α-cyano Α-cyanophenylacetic acid derivatives such as 2-methylphenylacetate and ethyl-α-cyanophenylacetate; 2,2′-dihydroxy-1,1′-binaphthyl, 6,6′-dibromo-2,2′-dihydroxy Bis-β-naphthol as exemplified by -1,1′-binaphthyl and bis (2-hydroxy-1-naphthyl) methane; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (eg, 2,4
-Dihydroxybenzophenone or 2 ', 4'-dihydroxyacetophenone); 3-methyl-1-phenyl
5-pyrazolone, such as -5-pyrazolone; reductones as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone;
Sulfonamidophenol reducing agents such as 2,6-dichloro-4-benzenesulfonamidophenol and p-benzenesulfonamidophenol; 2-phenylindane-1,3-
Dione and the like; chromanes such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman; 1,4-dihydropyridines such as 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine; Bisphenols (e.g., 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 (for example, 1-palmitic acid) And aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidones and certain indan-1,3-diones; chromanols (such as tocopherols). 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. The addition of additives known as "toning agents" that improve the image may increase the optical density. The toning agent may also be advantageous in forming a black silver image. The color-toning agent is preferably contained in an amount of 0.1 to 50% mol, more preferably 0.5 to 20% mol, per mol of silver on the surface having the image forming layer. 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 utilizing 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-tert-butylphthalazine,
Derivatives such as 5,7-dimethylphthalazine and 2,3-dihydrophthalazine) or metal salts; phthalazine and its derivatives and phthalic acid derivatives (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachloro Quinazolinedione, benzoxazine or naphthoxazine derivatives; rhodium complexes, such as hexachlororhodium, which function not only as a color tone control agent but also as a source of halide ions for silver halide formation in situ (III) ammonium, rhodium bromide, rhodium nitrate and hexachlororhodium (II
I) Potassium acid and the like; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide;
Benzoxazine-2,4 such as benzoxazine-2,4-dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione -Diones; pyrimidines and asymmetric-triazines (eg, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (eg, 3,6-dimercapto-1,4 -Diphenyl-1
H, 4H-2,3a, 5,6a-tetraazapentalene, and 1,4-di
(o-chlorophenyl) -3,6-dimercapto-1H, 4H-2,3a, 5,6
a-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. At least one of the image forming layers in the photosensitive heat-developable image forming material of the present invention is preferably an image forming layer containing the polymer latex described below in an amount of 50% by weight or more of the total binder. (Hereinafter, this image forming layer is referred to as “image forming layer in the present invention” and the polymer latex used for the binder is referred to as “polymer latex used in the present invention.” When the photosensitive heat-developable image forming material of the present invention is used for printing in which dimensional change is a problem, it is necessary 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 (Taira Okuda, edited by Hiroshi Inagaki, published by Kobunshi Kankokai (197
8))), `` Application of synthetic latex (Takaaki Sugimura, Yasuo Kataoka,
Edited by Souichi Suzuki and Keiji Kasahara, published by The Polymer Publishing Association (199
3)) "and" Synthesis of Synthetic Latex (Souichi Muroi, published by Kobunshi Kankokai (1970)) "and the like. The average particle size of the dispersed particles is preferably in the range of 1 to 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 a 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 used as a binder in the photosensitive heat-developable image forming material of the present invention is preferably different between the protective layer, the back layer and the image forming layer. In the image forming layer, the temperature is 40 ° C. or less to promote the diffusion of useful photographic materials during thermal development.
-30 to 40 ° C is preferred. 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. The minimum film forming temperature (MFT) of the polymer latex used in the present invention is -30 ° C to 90 ° C, more preferably 0 ° C.
About 70 ° C. is preferable. A film-forming auxiliary may be added to control the minimum film-forming temperature. The film-forming assistant is also called a plasticizer and is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of the polymer latex.
0)) ". Acrylic resin as the polymer species used in the polymer latex used in the present invention,
Examples include a vinyl acetate resin, a polyester resin, a polyurethane resin, a rubber resin, a vinyl chloride resin, a vinylidene chloride resin, a polyolefin resin, and a copolymer thereof. 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 polymer has a number average molecular weight of 5000 to 10000000, preferably 1
It is preferably about 10,000 to 100,000. 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 photosensitive heat-developable image forming 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 an example of an acrylic resin, Sebian A-4635,46583,4601 (all manufactured by Daicel Chemical Industries, Ltd.), Nipol Lx811, 814, 82
Polyester resins such as 1,820, 857 (all manufactured by Nippon Zeon Co., Ltd.) include FINETEX ES650, 611, 675, 850 (all manufactured by Dainippon Ink & Chemicals, Inc.), WD-size, WMS (all Eastman H) as polyurethane resin
YDRAN AP10, 20, 30, 40 (Dai Nippon Ink Chemical Co., Ltd.)
LACSTAR 7310K, 3307B, 4
700H, 7132C (all manufactured by Dainippon Ink and Chemicals, Inc.), Nipol L
x416, 410, 438C, 2507, (Nippon Zeon Co., Ltd.), etc., vinyl chloride resins such as G351, G576 (Nippon Zeon Co., Ltd.), etc., vinylidene chloride resins L502, L
513 (manufactured by Asahi Kasei Corporation), Aron D7020, D504, D5
071 (Mitsui Toatsu Co., Ltd.) and other olefin resins include Chemipearl S120 and SA100 (Mitsui Petrochemical Co., Ltd.)
And the like. These polymers may be used alone or as a blend of two or more as necessary.

In the image forming layer in the present invention, 50% by weight or more of the total binder is the above polymer latex.
It is preferable that the polymer latex accounts for at least% by weight. The image forming layer in the present invention has a hydrophilicity such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, and hydroxypropylmethylcellulose in the range of 50% by weight or less, preferably 10% by weight or less of the total binder, if necessary. A polymer may be added. The amount of these hydrophilic polymers added is 30% by weight of the total binder of the image forming layer.
Below, more preferably 5% by weight or less. The image forming layer in the invention is preferably prepared by applying an aqueous coating solution and then drying. However, the term “aqueous” as used herein means that 60% by weight or more of the solvent (dispersion medium) of the coating liquid 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 wt%.)

The total amount of the binder in the image forming layer in the invention is preferably in the range of 0.2 to 30 g / m ² , more preferably 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 the silver halide grains in a desired wavelength region when adsorbed on the 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 invention include, for example, RESEARCH DISCLOSURE Item 17643, Section IV-A (Dec. 1978
(P. 23) and Item 1831X (August 1979, p. 437). 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 include He-Ne laser, red semiconductor laser and L
For a so-called red light source such as an ED, see JP-A-54-18726.
Compounds of I-1 to I-38 described in JP-A-6-75322, 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. Compounds, dyes 1 to 20 described in JP-B-55-39818, compounds of I-1 to I-37 described in JP-A-62-284343, and I-1 described in JP-A-7-287338.
And the compound of I-34 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, JP-A-62-58239, JP-A-3-38638,
3-138642, 4-255840, 5-72659, 5-72661
Nos. 6-222491, 2-230506, 6-258757, 6-
No. 317868, No. 6-324425, Tokuyohei No. 7-500926, U.S. Patent
5,541,054), a dye having a carboxylic acid group (for example, JP-A-3-163440, 6-301141, the dye described in U.S. Pat. Cyanine dye (JP-A-4
7-6329, 49-105524, 51-127719, 52-80829
No. 54-61517, No. 59-214846, No. 60-6750, No. 63
No. -159841, JP-A-6-35109, JP-A-6-59381, JP-A-7-14653
No.7, No.7-146537, JP-T-Hei 55-50111, UK Patent 1,46
7,638 and US Pat. No. 5,281,515). In addition, U.S. Patent
Nos. 5,510,236 and 3,871,887, dyes described in Example 5, JP-A-2-96131 and JP-A-59-48753 are disclosed.
It 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,
Dissolved in a single or mixed solvent such as 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, N-dimethylformamide May be added to the emulsion. Further, as disclosed in U.S. Pat.No. 3,469,987, a dye is dissolved in a volatile organic solvent, the solution is dispersed in water or a hydrophilic colloid, and this dispersion is added to the emulsion. Method, JP-B-44-23389, 44-27555, 57
As disclosed in U.S. Pat. No. 2,220,91, a method of dissolving a dye in an acid and adding the solution to an emulsion, or adding an acid or a base to an emulsion as an aqueous solution in the presence of an acid or base, US Pat.
No. 822,135, 4,006,025, etc., a method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to an emulsion as disclosed in JP-A-53-102,
No. 733, a method of directly dispersing a dye in a hydrophilic colloid as disclosed in JP-A-58-105141, and adding the dispersion to an emulsion, as disclosed in JP-A-51-74624. In, dissolve the dye using a compound to red shift,
A method of adding the solution to the emulsion can also be used.
Also, ultrasonic waves can be used for the solution.

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 desalting, during the desilvering step and / or Alternatively, from the time after desalting 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. U.S. Pat. No. 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 the 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 photosensitive layer. 10 ^-1 mol is more preferred.

The silver halide emulsion according to the invention 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.
Nitron, 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, for example, as described in JP-A-50-119624.
No. 50-120328, No. 51-121332, No. 54-58022, No.
56-70543, 56-99335, 59-90842, 61-12964
No. 2, 62-129845, JP-A-6-208191, 7-5621,
Nos. 7-2781, 8-15809, U.S. Pat.No. 5,340,712,
Compounds such as those disclosed in US Pat. Nos. 5,369,000 and 5,464,737 can be mentioned. Salicylic acid derivatives are also preferred as the antifoggant preferably used in the present invention, and examples thereof include compounds represented by formula (I) described in Japanese Patent Application No. 11-5709, and specific examples are A-1 to A-1. -60 compounds. 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 known micronization means (for example, ball mill, vibrating ball mill, sand mill, colloid mill,
Jet mill, roller mill, etc.). Also,
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 emulsion 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 nmol to 1 mmol, more preferably 10 nmol to 100 μm per mol of silver applied.
Range of moles. The photosensitive heat-developable image forming 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 those described in U.S. Pat.
No. 9, No. 4, 152, 160, Japanese Patent Application No. 8-151242, No. 8-151241
And the compounds described in JP-A-8-98051 and the like. The benzoic acid may be added to any part of the photosensitive material, but it is preferably added to the layer having the photosensitive layer, more preferably to the organic silver salt-containing layer. The benzoic acid may be added at any time during the preparation of the coating solution, and when added to the organic silver salt-containing layer, may be added at any time from the preparation of the organic silver salt to the coating solution, but after the preparation of the organic silver salt. To just before application. 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 is preferably 1 μmol or more and 2 mol or less, more preferably 1 mmol or more and 0.5 mol or less per 1 mol of silver.

In the present invention, a mercapto compound, a disulfide compound, and a thione compound are contained in order to control development by suppressing or accelerating development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. be able to. When using a mercapto compound in the present invention, any structure may be used, but Ar-SM, Ar-SS-Ar
Is preferably represented by 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., those having one or more carbon atoms, preferably 1-4 carbon atoms), alkoxy ( For example, it may have one selected from a substituent group consisting of one or more carbon atoms, preferably having one to four carbon atoms) and aryl (which may have a substituent). Good. 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-hydrokilos-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 '-[3- (5-mercaptotetrazolyl) phenyl] urea, 2-mercapto-4-phenyloxazole, and the like, but the invention is not limited thereto. . The addition amount of these mercapto compounds is preferably in the range of 0.0001 to 1 mol per mol of silver in the emulsion layer, more preferably 0.01 to 1 mol per mol of silver.
It is in an amount of from 01 to 0.1 mol.

In the photosensitive layer according to the present invention, a polyhydric alcohol (for example, US Pat.
Glycerin and diols of the type described in U.S. Pat. No. 60,404), 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. The photosensitive heat-developable image forming material of the present invention may be provided with a surface protective layer for the purpose of preventing adhesion of the image forming layer. Any polymer may be used as the binder for the surface protective layer, but a polymer having a carboxylic acid residue is 100 mg / m ² or more.
It is preferable to contain 5 g / m ² or less. Examples of the polymer having a carboxyl residue include natural polymers (gelatin, alginic acid, etc.), modified natural polymers (carboxymethylcellulose, phthalated gelatin, etc.), synthetic polymers (polymethacrylate, polyacrylate, polyalkyl methacrylate / acrylate). Copolymer, polystyrene / polymethacrylate copolymer) and the like. The content of the carboxy residue of the polymer is 10
It is preferably from 10 mmol to 1.4 mol per 0 g.
Further, the carboxylic acid residue may form a salt with an alkali metal ion, an alkaline earth metal ion, an organic cation, or the like. Any anti-adhesion material may be used as the surface protective layer. 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.

As the image forming layer or the protective layer of the image forming layer, US Pat. No. 3,253,921, US Pat. No. 2,274,782, US Pat.
It can be used in photographic elements containing light absorbing materials and filter dyes as described in 527,583 and 2,956,879. Also, for example, U.S. Pat.
Dyes can be mordant as described in 282,699. The amount of the filter dye used is preferably such that the absorbance at the exposure wavelength is 0.1 to 3, and particularly preferably 0.2 to 1.5. Various dyes and pigments can be used in the photosensitive layer in the photosensitive heat-developable image forming material of the present invention from the viewpoint of improving color tone and preventing irradiation. Dyes and pigments used in the photosensitive layer may be any, for example, pigments and dyes described in the Color Index, specifically, pyrazoloazole dye, anthraquinone dye, azo dye, azomethine dye, oxonol dye, carbocyanine dye , Styryl dyes, triphenylmethane dyes, indoaniline dyes, indophenol dyes, organic pigments such as 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, JP-A-5-1651).
No. 47 described compounds 3-6-18 and 3-23-38), azomethine dyes (such as compounds 17-47 described in JP-A-5-341441),
Indoaniline dyes (e.g., compounds 11 to 19 described in JP-A-5-289227, compound 47 described in JP-A-5-341441,
5-165147 No. 2-10 to 11) and azo dyes
(Compounds 10 to 16 described in JP-A-5-341441).
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 purpose, generally 1 m ² per 1μg more
It is preferable to use it in a range of 1 g or less.

The photosensitive heat-developable image-forming material according to the present invention has a support having at least one photosensitive layer containing a silver halide emulsion on one side and a back layer on the other side, that is, a so-called one-sided surface. It is preferably a photosensitive material. In the present invention, the back layer has a maximum absorption of about 0.
It is preferably from 3 to 2.0. Desired range is 750
When it is from 1 to 1400 nm, the optical density at 750 to 360 nm is preferably from 0.005 to less than 0.5, more preferably an antihalation layer having an optical density from 0.001 to less than 0.3. Desired range is 750nm
If not more than the maximum absorption of the desired range before image formation is 0.3 or more and 2.0 or less, and further after 360-750 after image formation.
It is preferable that the antihalation layer has an optical density of 0.005 or more and less than 0.3. There is no particular limitation on the method of reducing the optical density after image formation to the above range, for example, a method of reducing the density by dyeing by heating to reduce the density by heating as described in Belgian Patent No. 733,706,
Japanese Patent Application Laid-Open No. Sho 54-17833 discloses a method of reducing the density by decoloring by light irradiation.

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 include 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 photosensitive heat-developable image-forming material of the present invention is a single-sided photosensitive material, a matting agent is added to the surface protective layer of the photosensitive emulsion layer and / or the back layer or the surface protective layer of the back layer to improve transportability. It may be added. 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. Patent Nos. 1,939,213, 2,701,245, 2,322,037, 3,2
62,782, 3,539,344, 3,767,448, etc., the organic matting agent described in each specification, 1,260,772, 2,192,241
Nos. 3,257,206, 3,370,951, 3,523,022,
Inorganic matting agents well-known in the art such as the inorganic matting agents described in the respective specifications such as 3,769,020 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, and starch derivatives such as carboxy starch, carboxynitrophenyl Gelatin hardened with a known hardener such as starch, urea-formaldehyde-starch reactant, and hardened gelatin formed into microcapsule hollow granules by coacervate hardening are preferably used. Can be. 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. The size and shape of the matting agent are not particularly limited, and those having an arbitrary 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 such that the Bekk smoothness is 250 seconds or less and 10 seconds or more, more preferably 180 seconds or less and 50 seconds or more. It is. In the present invention, the matting agent is preferably contained in the layer functioning as the outermost surface layer or the outermost surface layer of the light-sensitive material, or a layer close to the outer surface, and is contained in a layer acting as a so-called protective layer. Is preferred. The degree of matting of the emulsion surface protective layer may be any value as long as stardust failure does not occur, but the Beck smoothness is preferably 500 seconds or more and 10,000 seconds or less, particularly preferably 500 seconds or more and 2,000 seconds or less. is there. The photothermographic emulsion of the present invention is composed of one or more layers on a support. One layer is composed of an organic silver salt, a silver halide, a developer and a binder, and a toning agent,
Optional additional materials such as coating aids and other auxiliaries must be included. The two-layer configuration requires that the first emulsion layer (usually the layer adjacent to the base) contain an organic silver salt and silver halide and the second layer or both layers contain some other components. No. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. The composition of the multicolor photothermographic material may include a combination of these two layers for each color,
All components may be contained in a single layer as described in US Pat. No. 4,708,928. In the case of a multi-dye, multi-color photothermographic material, each emulsion layer generally employs a functional or non-functional barrier layer between the light-sensitive layers, as described in U.S. Pat.No. 4,460,681. By doing so, they are kept distinct from each other.

US Pat. Nos. 4,460,681 and 4,374,9
Backside resistive heating layer as shown in No. 21
stive heating layer) can also be used in a photosensitive heat developed photographic image system. A hardener may be used for each layer such as a photosensitive layer, a protective layer and a back layer in the photosensitive heat-developable image forming material of the present invention. Examples of hardeners include U.S. Pat.
No. 1,060, polyisocyanates described in JP-A-6-208193, epoxy compounds described in U.S. Pat. And the like are used. 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-62-17095
No. 0, U.S. Pat.No.5,380,644, a fluorine-based polymer surfactant described in JP-A-60-244945, JP-A-63-188135, a fluorine-based surfactant described in U.S. Pat. Polysiloxane surfactant described, JP-A-6-30
Examples include polyalkylene oxide and anionic surfactant described in No. 1140 and the like.

The photographic emulsion for thermal development used in the present 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, poly (vinyl acetal) films, polycarbonate films and related or resinous Materials, as well as glass,
Including paper, metal, etc. Flexible substrates, in particular coated with partially acetylated or baryta and / or α-olefin polymers, especially polymers of C 2-10 α-olefins such as polyethylene, polypropylene, ethylene-butene copolymers A coated paper support is 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 is heat-treated at 100 to 210 ° C. before coating the photographic emulsion for thermal development, is preferably used. Those having a high glass transition point are also preferable, and polyether ethyl ketone, polystyrene, polysulfone, polyethersulfone, polyarylate, polycarbonate and the like can be used.

The photosensitive heat-developable image-forming material of the present invention may be prepared, for example, by adding soluble salts (for example, chlorides and nitrates), deposited metal layers, and those described in US Pat. Such ionic polymers or insoluble inorganic salts as described in U.S. Pat.No. 3,428,451;
It may have a layer containing tin oxide fine particles described in JP-A-60-252349 and JP-A-57-104931. As a method for obtaining a color image using the photosensitive heat-developable image forming material of the present invention, JP-A-7-13295, page 10, left column, line 43 to 11 left column 40
There is a method described in the line. Also, as a stabilizer for color dye images, UK Patent No. 1,326,889, U.S. Patent No. 3,432,3
No. 00, No. 3,698,909, No. 3,574,627, No. 3,573,
Nos. 050, 3,764,337 and 4,042,394. The photothermographic emulsions used in this invention can be coated by a variety of coating operations, including dip coating, air knife coating, flow coating, or extrusion coating using a hopper of the type described in US Pat. No. 2,681,294. If desired, two or more layers can be coated simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095.

In the light-sensitive heat-developable image-forming material of the present invention, additional layers such as a dye-receiving layer for receiving a transfer dye image, an opaque layer when reflective printing is desired, and a protective topcoat layer And a primer layer known in photothermography. It is preferable that the image forming material of the present invention can form an image with only one image forming material, and it is preferable that a functional layer such as an image receiving layer necessary for image formation does not become another image forming material. The photosensitive heat-developable image-forming material of the present invention may be developed by any method, but is usually developed by elevating the temperature of the photosensitive material exposed imagewise. 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 of preventing the processing unevenness due to the dimensional change during the above-mentioned heat development of the photosensitive heat-developable image forming material of the present invention, after heating for 5 seconds or more so that an image does not appear at a temperature of 80 ° C. or more and less than 115 ° C. And a method of forming an image by heat development at 110 ° C. or higher (a so-called multi-stage heating method) is effective.

The image forming material of the present invention may be exposed by any method, but a laser beam is preferred as an exposure light source. As laser light according to the present invention, gas lasers,
YAG lasers, dye lasers, semiconductor lasers and the like are preferred. Further, a semiconductor laser and a second harmonic generation element can be used. The image forming material of the present invention has a low haze at the time of exposure, and tends to cause interference fringes.
As the interference fringe generation prevention technology, a technology disclosed in Japanese Patent Application Laid-Open No. 5-113548 or the like that obliquely enters a laser beam into a photosensitive material or a multi-mode laser disclosed in WO95 / 31754 or the like is used. There are known methods for performing these methods, and it is preferable to use these techniques. To expose the image forming material of the present invention, SPIE vol.169 Laser Printing 116-
As disclosed in page 128 (1979), JP-A-4-51043, and WO95 / 31754, it is preferable to expose the laser beams so that they overlap each other so that the scanning lines are not visible.

FIG. 1 shows an example of the configuration of a heat developing machine used for the heat developing process of the photosensitive heat-developable image forming material of the present invention.
FIG. 1 is a side view of the heat developing machine. The heat developing machine shown in FIG. 1 has a carry-in roller pair 11 (a lower roller is a heat roller) for carrying the photosensitive heat-developable image forming material 10 into a heating section while correcting and preheating the heat-developable photosensitive heat-developable image forming material 10 and a heat-developed heat-developed heat-developed image. It has a carry-out roller pair 12 that carries out the heat-developable image forming material 10 from the heating unit while correcting it into a planar shape. The photosensitive heat-developable image forming material 10 is a pair of carry-in rollers 1
While being transported from 1 to the discharge roller pair 12, it is thermally developed. The conveying means for conveying the photosensitive heat-developable image forming material 10 during the heat development is provided with a plurality of rollers 13 on the side where the surface having the image forming layer is in contact, and on the side where the back surface on the opposite side is in contact. A smooth surface 14 on which a non-woven fabric (for example, made of polyphenylene sulfite or Teflon) is attached is provided. Photothermographic image-forming material 10
Is a plurality of rollers 13 that contact the surface having the image forming layer.
, The back surface slides on the smooth surface 14 and is conveyed. The heating means is the upper part of the roller 13 and the smooth surface 14
A heater 15 is provided at the lower part of the photosensitive heat-developable image forming material 10 so as to be heated from both sides. As a heating means in this case, a plate heater or the like can be used. The clearance between the roller 13 and the smooth surface 14 varies depending on the member of the smooth surface, but is appropriately adjusted to a clearance that allows the photosensitive heat-developable image forming material 10 to be conveyed. Preferably 0
1 mm.

The surface material 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 photosensitive heat-developable image forming material 10, but the material of the roller surface is silicon rubber, and the material of the smooth surface is aromatic polyamide or Teflon (PTFE). Non-woven fabrics are preferred. It is preferable to use a plurality of heaters as the heating means and to set the heating temperature freely. The preheating section upstream of the heat development processing section has a temperature lower than the heat development temperature (for example, about 10 to 30 ° C. lower) and a temperature sufficient to evaporate the amount of water in the photosensitive heat development image forming material. And the time are desirably set, and it is preferable that the temperature is higher than the glass transition temperature (Tg) of the support of the photosensitive heat-developable image forming material 10 so that development unevenness does not occur. 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 so as not to deform the photosensitive heat-developable image forming material. As described above, the description has been made in accordance with the illustrated example. However, the present invention is not limited to this example.
The thermal developing machine used in the present invention may have various configurations. 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.

[0112]

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. (Example 1)1. Preparation of silver halide emulsion (emulsion A)  700ml of alkali-treated gelatin (with calcium content
Less than 2700 ppm) 11 g and potassium bromide 30 mg, benze
Dissolve 10 mg of sodium thiosulfonate and bring the temperature to 40 ° C
After adjusting the pH to 5.0, 159 m of an aqueous solution containing 18.6 g of silver nitrate
l and potassium bromide at 1 mol / l (NH_Four)_TwoRhCl_Five
(H_TwoO) 5 × 10^-6Mol / l and K_ThreeIrCl₆To
2 × 10^-FiveDo not keep the aqueous solution containing mol / l at pAg 7.7.
It takes 6 minutes and 30 seconds by the control double jet method
Was added. Then, 476 ml of an aqueous solution containing 55.5 g of silver nitrate and odor
1 mol / liter of potassium iodide and K_ThreeIrCl₆2 × 10
^-Five Keep the halogen salt aqueous solution containing pAg 7.7
28 minutes 30 seconds by the control double jet method
And added. After that, the pH is lowered to cause coagulation and sedimentation and desalination.
0.17 g of compound A and a low molecular weight of 15,000
Gelatin gelatin (less than 20 ppm as calcium content) 51.
The solution was adjusted to pH 5.9 and pAg 8.0 by adding 1 g. The resulting particles are flat
Uniform grain size 0.08μm, projected area variation coefficient 9%, (100) face ratio
The cubic particles had a rate of 90%. The halogenation thus obtained
The temperature of the silver particles is raised to 60 ° C, and benzenethios
Add 76 μmol of sodium sulfonate and after 3 min.
71 μmol of thiothiourea was added, and the mixture was aged for 100 minutes.
Hydroxy-6-methyl-1,3,3a, 7-tetraza
5 × 10 inden^-FourAfter mole addition, the temperature was lowered to 40 ° C.
Thereafter, the temperature was maintained at 40 ° C., with respect to 1 mole of silver halide.
12.8 × 10^-FourMolar sensitizing dye A, 6.4 × 10^-3Mole of
Compound B was added with stirring, and quenched to 30 ° C after 20 minutes.
Thus, the preparation of silver halide emulsion A was completed.

[0113]

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[0114]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 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 conductivity of the filtrate is 20 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.

[0116]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% aqueous solution of Ma-MP-203, manufactured by Nissin Chemical Co., Ltd.
0.1 g of INOL 104E, 2 g of methanol and 48 ml of water.
The mixture was stirred well and left as a slurry for 3 hours. Then 1
Prepare 360g of zirconia beads with mm and with slurry
Put in a vessel and disperser (1 / 4G sand grinder
3 hours by dispersing with a reducing agent solid
A fine particle dispersion was prepared. The particle size is 80% by weight of the particles
It was 0.3 μm or more and 1.0 μm or less.

[0117]4. Preparation of solid fine particle dispersion of antifoggant
Made  (Compound of the general formula (I)) 30 g of the compound of the general formula (I)
On the other hand, 4 g of MP-203 of MP polymer manufactured by Kuraray Co., Ltd.
Material C 0.25g and water 66g are added and stirred well, then 0.5mm
Prepare 200g of zirconia silicate beads of slurry
Into a vessel together with a dispersing machine (1 / 16G
Under mill: IMEX Co., Ltd.)
A fine particle dispersion was prepared. Particle size changes dispersion time
Adjusted. See table for particle size, dispersion time, and compound type.
Described in 1. (Compound of the general formula (II)) Compound 30 of the general formula (II)
3g of MP-203 of MP polymer manufactured by Kuraray Co., Ltd.
And add 87 ml of water and stir well to obtain a slurry for 3 hours
I left it. Then, the preparation of the above-mentioned solid dispersion of reducing agent solid
In the same manner as described above, a solid fine particle dispersion was prepared. The particle size is
The dispersion time was varied and adjusted. Particle size, dispersion
Meanwhile, the types of compounds are shown in Table 1.

[0118]5. Preparation of emulsified dispersion of antifoggant  (Compound of the general formula (I)) 50 g of the compound of the general formula (I)
The solution dissolved in 60 g of ethyl acetate was used as solution A. Kuraray Co., Ltd.
Water to MP-203 (made in Table 1)
The solution adjusted to 100 g by water addition was designated as solution B. A
Solution B and solution B are mixed and homogenized (HIGH-FLEX HOMOGENIZ
ER; manufactured by SMT Co., Ltd.)
Emulsification was performed at an emulsification time of 5 minutes and an emulsification temperature of 60 ° C. Emulsified
After the dispersion, 140 g of water was added, and the organic solvent was removed at a heating temperature of 60.
C. and the solvent was removed until the weight became 166 g. Remaining
The amount of existing ethyl acetate was 0.1% or less. Particle size of MP203
The amount was varied and adjusted. Particle size and compound type
It is described in Table 1. (Compound of the general formula (II)) Compound 50 of the general formula (II)
g solution in 60 g of methyl isobutyl ketone
Was. MP-203 manufactured by Kuraray Co., Ltd.
Water) and adjusted to 100 g by adding water.
The solution was designated as solution B. A solution and B solution are mixed and homogenized (HIG
H-FLEX HOMOGENIZER; SMT Co., Ltd.)
Number of revolutions = 12000 rpm, emulsification time = 5 minutes, emulsification temperature = 60 ° C.
And emulsified. After emulsification and dispersion, 140 g of water was added, and the organic solvent was removed.
Perform the agent at a heating temperature of 80 ° C until the weight becomes 166 g.
The solvent was removed. The amount of residual methyl isobutyl ketone is 0.1
% Or less. Particle size is adjusted by changing the amount of MP203
did. Table 1 shows the particle size and compound type.

[0119]6. Preparation of solid fine particle dispersion of ultra-high contrast agent  For 10 g of the nucleating agent shown in Table 1, 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.
Into a dispersing machine (1 / 16G sand grinder mill:
Disperse for 10 hours with Imex Co., Ltd.
A powder was prepared. Particle size: 80% by weight of particles is 0.1 μm or less
It was 1.0 μm or less and had an average particle size of 0.5 μm.

[0120]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
A 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 solids Compound of general formula (I) Kind and amount (mol) shown in Table 1 Compound of general formula (II) Kind and amount (mol) shown in Table 1 Sodium ethylthiosulfonate 0.30 g 4-methylbenzotriazole 1.04 g Polyvinyl alcohol (PVA-235 manufactured by Kuraray Co., Ltd.) 10.8 g 6-iso-propylphthalazine 15.0 g Sodium dihydrogen orthophosphate dihydrate 0.37 g Super hardening agent Table Kind and amount (mol) described in 1 Dye A Coating amount at which the optical density of 783 nm becomes 0.3 (0.37 g as a standard) 0.06 mol as silver halide emulsion A Ag amount

[0121]

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[0122]8. Preparation of coating solution for lower protective layer of emulsion surface  Methyl methacrylate / styrene / 2-ethylhexylurea
Acrylate / 2-hydroxyethyl methacrylate / ac
Polymer of lylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%)
Latex solution (copolymer, glass transition temperature 57 ℃, solid
Compound D as a film-forming aid with a concentration of 21.5%
H to 956 g)_Two Add O
Compound E 1.62 g, Compound S 3.15 g, matting agent (Polystyrene
1.98 g of Len particles, average particle size 7 μm) and polyvinyl alcohol
23.6 g of coal (Kuraray Co., Ltd., PVA-235) was added.
H_TwoO was added to prepare a coating solution.9. Preparation of coating solution for protective layer on emulsion surface  Methyl methacrylate / styrene / 2-ethylhexylurea
Acrylate / 2-hydroxyethyl methacrylate / ac
Polymer of lylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%)
Latex solution (copolymer, glass transition temperature 54 ℃, solid
Compound D as a film-forming aid with a concentration of 21.5%
H to 630 g)_Two Add O
Lunava wax (Chukyo Yushi Co., Ltd., Cellosol 52
4) 30 wt% solution 6.30 g, Compound E 0.72 g, Compound F 7.95
g, compound S 0.90 g, matting agent (polystyrene particles, flat
1.18 g of average particle size 7 μm) and polyvinyl alcohol
8.30 g of PVA-235 manufactured by Re Co., Ltd._TwoAdd O
Thus, a coating solution was prepared.

[0123]

Embedded image

[0124]10. PET support with back / undercoat layer
Making the 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
I created an Irum. 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 of 90% by weight and a shell of 10% by weight, core: vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic acid = 93/3/3 / 0.9 / 0.1 (% by weight), shell: weight consisting of vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic acid = 88/3/3/3/3 (% by weight) Polymer latex with average molecular weight of 38000) 3.0g / m as solid content^Two  2,4-dichloro-6-hydroxy-s-triazine 23mg / m^Two  Matting agent (polystyrene, average particle size 2.4μm) 1.5mg / 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 0.2 mg / 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 Amount of coating at which optical density of 783 nm becomes 1.2 SnO_Two/ Sb (9/1 weight ratio, acicular fine particles, major axis / minor axis = 20-30, manufactured by Ishihara Sangyo Co., Ltd.)^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)) solid 1000mg / m as quantity^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 PET with back / undercoat layer produced in this way
Put the support in a 200m long heat treatment zone set at 160 ° C,
Tension 3kg / cm^TwoAnd transported at a transport speed of 20 m / min. (7-2) Post heat treatment Following the above heat treatment, pass through the 40 ° C zone for 15 seconds.
Heat treatment was performed and the film was wound up. The winding tension at this time is 10
kg / cm^TwoMet.

[0125]

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[0126]11. Preparation of photosensitive heat-developable image forming material  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 1.7 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 photosensitive developed image forming material. Profit
Surface p on the image forming side of the photosensitive heat-developable image forming material
H is 4.9, Beck smoothness is 660 seconds, and the opposite film surface p
H was 5.9 and Beck smoothness was 560.

[0127]12. Evaluation of photographic performance  (Exposure treatment) The obtained photosensitive heat-developable image forming material is
Diameter (FWHM of 1/2 of beam intensity) 12.56μm, laser
-Equipped with a semiconductor laser with an output of 50 mW and an output wavelength of 783 nm
Using a single-channel cylindrical inner surface laser exposure system
The exposure time by changing the number of rotations of the mirror.
And adjust the exposure by changing the output value.
^-8Exposure in seconds. At this time, the overlap coefficient is 0.449
did. (Heat development processing)
Roller surface material of heat development processing section using heat development machine
The quality is silicone rubber and the smooth surface is Teflon non-woven fabric.
Heat at 90-100 ° C for 5 seconds, heat at 120 ° C for 20 seconds
A development process was performed. Note that the temperature accuracy in the width direction is ± 1 ° C.
there were. (Evaluation of photographic performance) Macbeth TD904
The measurement was performed using a densitometer (visible density). The result of the measurement is Dmin,
Sensitivity (reciprocal of the ratio of exposure dose giving a density 1.5 higher than Dmin
The photosensitive heat development image formation described in Table 1 was evaluated by the relative value of
Evaluated by Dmax, γ (contrast)
(Fresh photographic properties in Table 1). γ is the exposure amount
With the number as the horizontal axis, the density of 0.3 and 3.0
It was represented by the slope of a straight line connecting the points. In addition, evaluation of storage stability
The photosensitive heat-developable image forming material at 25 ° C. and a humidity of 30% RH.
After adjusting the humidity and cutting it into a sheet state, put three sheets in a moisture-proof bag
Make two sets each and store them at 50 ° C for 3 days
And then the photosensitive heat-developable image forming material before storage
Exposure as described above for the central part (second sheet) of three stacked sheets after storage
And heat development processing, and Dmin, sensitivity, Dmax, γ (contra
(After the aging test in Table 1)
Field). (Evaluation of pinhole) The exposure amount at which Dmax appears in the obtained photosensitive material
Samples exposed to light and subjected to heat development in the same manner as above
Shakasten (Seiko Co., Ltd.)
Expression: KSHD5)) Gives translucent light from behind and magnifies from front
(Magnification: 10x) to determine the peak within 9 square centimeters.
The number of holes was counted. Each photosensitive heat-developable image forming material
Table 1 shows the results of the above evaluations of the materials.

[0128]

[Table 1]

(Results) According to the combination of the present invention, a photosensitive heat-developable image forming material having few pinholes and excellent storability can be provided, and the method of dispersing the antifoggant dispersion used in the present invention can be a solid. The emulsified dispersion has less pinholes and is excellent in storage stability as compared with the dispersion.

[0130]

According to the present invention, it is possible to provide a photosensitive heat-developable image-forming material having a good surface condition and excellent storability for photoengraving (especially for scanners and imagesetters) and for medical images. Was.

[Brief description of the drawings]

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 photosensitive heat-developable image forming 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 (6)

[Claims] 1. At least one surface of a support,
(A) photosensitive silver halide, (b) non-photosensitive reducible organic silver salt, (c) reducing agent, (d) binder, (e)
An antifoggant dispersion having an average particle size of 0.3 μm or less and a maximum particle size of 2 μm or less.
a photosensitive heat-developable image-forming material having a particle size of not more than μm. 2. The antifoggant is a compound of the general formula (I) or (II) or a compound having a bisphenol structure in which the compound of the general formula (II) is bonded through one carbon atom. 2. The photosensitive heat-developable image forming material according to claim 1, wherein: Embedded image [In the general formula (I), Q represents an alkyl group, an aryl group or a heterocyclic group, and X ₁ and X ₂ each independently represent a halogen atom. Z represents a hydrogen atom or an electron-withdrawing group. Y is -C (= O) -, - SO- or -SO ₂ - represents a. m represents 0 or 1. In the general formula (II), M represents a hydrogen atom or a k-valent cation, and R represents a substituent. n is an integer of 0 to 4, and when n ≧ 2, a plurality of R
May be the same or different. k is an integer of 1 or more, and when M is a hydrogen atom, k = 1. ] 3. The photothermographic image-forming material according to claim 1, wherein the antifoggant dispersion is a solid fine particle dispersion. 4. The photothermographic image-forming material according to claim 1, wherein the antifoggant dispersion is an emulsified dispersion. 5. The photosensitive heat-developable image forming material according to claim 1, further comprising a super-high contrast agent. 6. A super-high contrast agent represented by the following general formula (III):
At least one substituted alkene derivative, substituted isoxazole derivative and acetal compound represented by (V)
6. The photosensitive heat-developable image forming material according to claim 5, wherein the material is used as a seed. Embedded image [In the general formula (III), R ¹ , R ² , and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the general formula (III), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure. In the general formula (IV), R
⁴ represents a substituent. In the general formula (V), 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, a hetero group. Represents a ring oxy group, a heterocyclic thio group, or a heterocyclic amino group. In the general formula (V), X and Y or A and B may combine with each other to form a cyclic structure. ]