JPH1138552A - Heat developing photographic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat developing photographic material suitable for plate making, very high in contrast, extremely little in photographic performance change and fogging due to the change of the developing temp. and time of heat development and having excellent stability of heat development by incorporating a reductive silver salt, a reducing agent, an ultrahigh contrast agent, a binder and a specified compd. SOLUTION: This heat developing photographic material contains a reductive silver salt, a reducing agent, an ultrahigh contrast agent, a binder and at least one kind of compd. expressed by the formula. In the formula, Z1 is an aliphatic hydrocarbon group or aryl group and Z2 is an aryl group. The heat developing photographic material contains a ultrahigh contract agent and is suitable for a plate making process. By incorporating a disulfide compd. expressed by the formula, both of ultrahigh contrast and photographic performance such as low fog and high sensitivity can be obtd. Also, changes in the photographic performances due to changes in the conditions of temp. and time during heat development can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable photographic material. As the photothermographic material, there are a photothermographic material containing silver halide as a photocatalyst and a thermosensitive material utilizing only a thermal reaction. The present invention particularly relates to a heat-developable photosensitive material, and more particularly to a heat-developable ultra-high contrast light-sensitive material suitable for printing plate making which has very little change in photographic sensitivity and fog due to fluctuations in development temperature and time during heat development and has excellent development processing stability. Things.

[0002]

2. Description of the Related Art In the field of printing, an image forming system exhibiting ultra-high contrast (especially gamma of 10 or more) photographic characteristics is required in order to improve reproduction of continuous tone images or line images by using halftone dots. Although it is provided, it is strongly desired to reduce the processing waste liquid from the viewpoint of environmental protection and space saving, and it has been studied and the waste liquid has been considerably reduced in recent years. It is impossible not to emit at all. Therefore, there is a need in the art for a heat development processing system which eliminates the use of solution processing chemicals and is simpler and does not damage the environment.

An image forming method using a photothermographic material in which a developing step is performed by heat treatment has been proposed. For example, Japanese Patent Publication No. 43-4924, Japanese Patent Publication No. 44-6582,
No. 6-6074, JP-A-48-97523, JP-A-Hei-7
No.-2781, US Pat. No. 5,468,603, etc., but the gamma (gradation) is soft and not used for printing plate making.

[0004] In the printing field, as described above, ultra-high contrast photographic properties are desired, and obtaining ultra-high contrast performance by using a hydrazine derivative has been proposed in, for example, US Pat. No. 5,496,695. However, when a hydrazine derivative is used, there is a problem that a stable image cannot be obtained due to a large change in sensitivity due to a change in temperature or time of thermal development, and improvement is desired.

[0005] Also, fogging due to thermal development is a major problem. Many studies have been made to reduce fogging of silver halide light-sensitive materials for thermography. For example, US Pat. No. 3,589,903 discloses a mercury salt. In addition, US 4,152,160 discloses carboxylic acids such as benzene and phthalic acid, US 4,784,
No. 939, benzoylbenzene compound, US Pat. No. 4,569,906, indane or tetralin carboxylic acid, US Pat.
No. 7 discloses a dicarboxylic acid and US Pat. No. 4,626,500 discloses a heteroaromatic carboxylic acid. US4,546,075, US4,75
6,999, US4,452,885, US3,874,946 and US3,95
No. 5,982 discloses halogenated compounds. US5,0
No. 28,523 discloses halogen atoms combined with a halogen molecule or a heteroatom ring. US Pat. No. 4,103,312 and GB 1,502,670 are palladium compounds, US Pat. No. 4,128,428 is a metal of irons, US Pat. No. 4,123,374, US Pat.
US 4,125,430 discloses substituted triazoles, US 4,213,784
US Pat. No. 4,245,033 and JP-A-51-26019, sulfur compounds, US Pat. No. 4,002,479, thiouracils, JP-A-50-12
No. 3331 includes sulfinic acid, US 4,125,403, US 4,152,160
No. 4,307,187 discloses a metal salt of thiosulfonic acid, JP-A-53-20923 and JP-A-53-19825 describe a combined use of a metal salt of thiosulfonic acid and sulfinic acid, Japanese Patent Publication No. 62-50810,
JP-A-7-209797 and JP-A-9-43760 disclose thiosulfonic acid esters. In addition, JP
No. 42529 and JP-B-63-37368 disclose disulfide compounds. There is no description in any of these documents regarding the effect on the fluctuation of sensitivity due to the heat development conditions in a super-high contrast material using a super-high contrast agent.

Japanese Patent Publication No. 6-21925 discloses the use of a hydrazine derivative and a disulfide in a silver halide photographic material which is developed using a developing solution. Describes the effect of improving the stability of photographic performance, but does not describe any desired effect such as the stability of heat development processing in a heat development system.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a super-high contrast, extremely little change in photographic performance and fogging due to fluctuations in development temperature and time during thermal development, and excellent heat development processing stability. Another object of the present invention is to provide a heat-developable photographic material typified by a heat-developable ultra-high contrast photosensitive material suitable for printing plate making.

[0008]

The above object has been achieved by the following means. (1) (a) a reducible silver salt, (b) a reducing agent, (c) a super-high contrast agent, (d) a binder, and (e) a general formula (1)
A photothermographic material comprising at least one compound represented by the formula:

[0009]

Embedded image

[In the general formula (1), Z ₁ represents an aliphatic hydrocarbon group or an aryl group, and Z ₂ represents an aryl group. (2) The photothermographic material according to the above (1), which contains a photosensitive silver halide as a photocatalyst.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The photothermographic material of the present invention is preferably a photothermographic material containing a photosensitive silver halide, and has a super-high contrast suitable for printing plate making containing a super-high contrast agent. By including a disulfide compound represented by the general formula (1) in such a heat-developable photographic material, compatibility between ultra-high contrast property and photographic performance such as low fog and high sensitivity can be achieved, and heat development can be performed. Variations in photographic performance due to changes in temperature and time conditions can be suppressed.

First, the general formula (1) used in the present invention will be described in detail. The general formula (1) is shown below.

[0013]

Embedded image

In the general formula (1), Z ₁ represents an aliphatic hydrocarbon group or an aryl group, and Z ₂ represents an aryl group.

The aliphatic hydrocarbon group represented by Z ₁ in the general formula (1) is a linear, branched or cyclic alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 12 carbon atoms). To 8, for example, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, n-octyl, n-dodecyl, tert-amyl, cyclohexyl and the like. Alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 2 carbon atoms).
8, for example, vinyl, allyl, 2-butenyl, 3-pentenyl and the like. ), An alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms, such as a propargyl group and a 3-pentynyl group). It may have a substituent.

The aliphatic hydrocarbon group represented by Z ₁ is preferably an alkyl group, and more preferably a chain alkyl group.

As the substituent, for example, an aryl group (preferably having 6 to 30, more preferably 6 to 20, and particularly preferably 6 to 12 carbon atoms such as phenyl, p-methylphenyl, naphthyl and the like can be mentioned. ), An amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10, and still more preferably 0 to 6, and examples thereof include amino, methylamino, dimethylamino, diethylamino, and dibenzylamino. ), An alkoxy group (preferably having 1 to 20, more preferably 1 to 12, and particularly preferably 1 to 8; examples thereof include methoxy, ethoxy, and butoxy), and an aryloxy group (preferably, It has 6 to 20 carbon atoms, more preferably 6 to 16, and particularly preferably 6 to 12, and examples thereof include phenyloxy and 2-naphthyloxy. A sil group (preferably having 1 to 20 carbon atoms, more 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, for example, acetoxy, benzoyloxy, etc.), an acylamino group (preferably having 1 carbon atom). -20, more preferably 2-16, particularly preferably 2-10, for example, acetylamino, propionylamino, butyrylamino, valerylamino, benzoylamino and the like, and an alkoxycarbonylamino group (preferably having 2 carbon atoms). -20, more preferably 2-16, particularly preferably 2-12, for example, methoxycarbonylamino and the like.), An aryloxycarbonylamino group (preferably having 7-20 carbon atoms, more preferably 7-7 carbon atoms). 16,
Particularly preferably, it is 7 to 12, and examples thereof include phenyloxycarbonylamino. ), A sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 20 carbon atoms)
16, particularly preferably 1 to 12, for example, methanesulfonylamino, octanesulfonylamino, benzenesulfonylamino and the like. ), A sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 16,
Particularly preferred is 0 to 12, for example, sulfamoyl, methylsulfamoyl, dimethylsulfamoyl,
Phenylsulfamoyl and the like. ), A carbamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0
To 16, particularly preferably 0 to 12, and examples include carbamoyl, diethylcarbamoyl, phenylcarbamoyl and the like. ), A ureido group (preferably having 1 carbon atom)
-20, more preferably 1-16, particularly preferably 1-12, for example, ureide, methylureide, phenylureide, naphthylureide and the like. ), An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms such as methylthio and ethylthio, etc.), and an arylthio group (preferably having 6 to carbon atoms). 20, more preferably 6-16,
Particularly preferably, it is 6 to 12, for example, phenylthio and the like. ), A sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms)
And for example, mesyl, tosyl and the like. ), A sulfinyl group (preferably having 1 to 20, more preferably 1 to 16, particularly preferably 1 to 12, and examples thereof include methanesulfinyl and benzenesulfinyl), and a thioureido group (preferably having a carbon number of 1). 1 to 20, more preferably 1 to 16, particularly preferably 1
To 12, for example, thioureido, methylthioureide, phenylthioureide and the like. ), A phosphoramide group (preferably having 1 to 20 carbon atoms, more preferably 1
To 16, particularly preferably 1 to 12, for example, diethylphosphoramide, phenylphosphoramide, diphenylphosphoramide 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, oxolanyl, 1,3-dione-isoindolyl and the like), disulfide group and the like. Among them, hydroxy group,
A mercapto group, a sulfo group, a sulfino group, a carboxyl group, a phosphono group, a phosphino group, and the like may form a salt. These substituents may be further substituted. When there are two or more substituents, they may be the same or different.

The substituent of the aliphatic hydrocarbon group represented by Z ₁ is preferably a halogen atom, an aryl group, an alkoxy group, a heterocyclic group, a cyano group, an acyl group, an alkoxycarbonyl group, a sulfamoyl group, a carbamoyl group,
Carboxyl group, sulfo group, hydroxy group, nitro group, more preferably halogen atom, aryl group,
A carboxyl group, an alkoxycarbonyl group, a hydroxy group, a heterocyclic group, a cyano group, an acyl group, and a nitro group.

The aryl group represented by Z ₁ and Z ₂ is preferably a monocyclic or condensed aryl group having 6 to 30 carbon atoms, more preferably a monocyclic or condensed aryl group having 6 to 20 carbon atoms. And, for example, phenyl, naphthyl and the like can be mentioned, and a phenyl group is particularly preferred. Z ₁ and Z ₂ may be the same or different from each other. Z ₁ and Z
Aryl group represented by ₂ may have a substituent, in addition to those exemplified as the substituents for the aliphatic hydrocarbon group as the substituent represented by e.g. Z _1, an alkyl group (preferably having a carbon number of 1 -20, more preferably 1-12, particularly preferably 1-8, for example methyl, ethyl,
iso-propyl, tert-butyl, n-octyl,
tert-amyl, cyclohexyl and the like. ), 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, and examples include a propargyl group and a 3-pentynyl group. ) Can be applied.

The substituent of the aryl group represented by Z ₁ and Z ₂ is preferably an alkyl group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group,
Acylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfonylamino group,
Carbamoylamino group, carbamoyl group, sulfamoyl group, ureido group, alkylthio group, arylthio group,
A sulfinyl group, a sulfonylthio group, a thiosulfonyl group, a thioureido group, a carboxyl group, a sulfo group, a hydroxy group, a halogen atom, a cyano group, a nitro group, a heterocyclic group, a phosphoric acid amide group, and more preferably an alkyl group, Alkoxy, alkoxycarbonyl, carbamoyl, sulfamoyl, aryloxycarbonylamino, sulfonylamino, ureido, thioureido, acylamino, halogen, cyano, hydroxy, carboxyl, nitro, heterocyclic , A phosphoric amide group.

Next, specific examples of the compound represented by the general formula (1) are shown, but the present invention is not limited thereto.

[0022]

Embedded image

[0023]

Embedded image

[0024]

Embedded image

[0025]

Embedded image

[0026]

Embedded image

[0027]

Embedded image

As the compound represented by the general formula (1) of the present invention, a commercially available compound may be used. For example, pages 85 to 120 of "Organic Sulfur Chemistry (Synthetic Reaction)", edited by Doujin Kagaku (Thiol oxidation reaction,
(A reaction between sulfenyl chloride and thiol, a reaction between thiol sulfonate and thiol, a reaction between Bunte salt and thiol, etc.).

The compound of the general formula (1) according to the present invention can be prepared from water or a suitable organic solvent such as alcohols (methanol,
It can be used by dissolving it in ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethyl sulfoxide, methyl cellosolve and the like.

Further, by a well-known emulsification and dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate or an auxiliary solvent such as ethyl acetate or cyclohexanone is used for dissolution, and An emulsified dispersion can be prepared and used. Alternatively, the powder can be dispersed in water by a ball mill, a colloid mill, a sand grinder mill, a Manton-Gaulin, a microfluidizer, or an ultrasonic wave by a method known as a solid dispersion method.

The compound of the general formula (1) of the present invention can be used as a layer on the side of a silver halide emulsion layer which is an image forming layer with respect to a support,
That is, it may be added to the silver halide emulsion layer or any other layer, but is preferably added to the silver halide emulsion layer or a layer adjacent thereto.

The amount of the compound of the present invention represented by the general formula (1) is represented by a molar amount relative to 1 mol of silver, and is preferably 1 ×.
10 ^{-5 to} 5 × 10 ^-1 mol / mol Ag, more preferably,
5 × 10 ^-5 to 1 × 10 ^-1 mol / mol Ag, more preferably 1 × 10 ^{-4 to} 5 × 10 ^-2 mol / mol Ag. These compounds may be used alone or in combination of two or more.

In the present invention, a super-high contrast agent is used for forming a super-high contrast image. Examples of the ultra-high contrast agent that can be used in the present invention include, for example, U.S. Patent Nos. 5,464,738 and 5,496,695,
6,512,411, 5,536,622, Japanese Patent Application No. 7-2286
No. 27, No. 8-215822, No. 8-130842, No. 8-148113, No.
Nos. 8-156378, 8-148111, and hydrazine derivatives described in 8-148116, or compounds having a quaternary nitrogen atom described in Japanese Patent Application No. 8-83566 and U.S. Pat.
The acrylonitrile compound described in No. 515 can be used. Specific examples of the compound include the aforementioned U.S. Pat.
Compounds 1 to 10 of No. 4,738, H-1 to H-28 of No. 5,496,695, I-1 to I-86 of Japanese Patent Application No. 8-215822, H-1 to H-6 of No. 8-130842.
2, 1-1-11-2 of the 8-148113, 1-50 of the 8-148111,
Nos. 1 to 40 of 8-148116, P-1 to P-26 and T-1 to T-18 of 8-83566, and CN-1 to CN-13 of U.S. Pat.No. 5,545,515. .

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, amine compounds described in U.S. Pat.No. 5,545,505, specifically AM-1 to AM-5, hydroxamic acids described in 5,545,507, specifically HA-1 to HA-11, and the like.
Acrylonitrile described in 5,545,507, specifically C
Hydrazine compounds described in N-1 to CN-13 and 5,558,983, specifically CA-1 to CA-6, onium salts described in Japanese Patent Application No. 8-132836, specifically A-1 to A-42, B-1 to
B-27, C-1 to C-14 and the like can be used.

The methods for synthesizing, adding, and adding amounts of these super-high contrast agents and high-contrast accelerators can be carried out as described in each of the cited patents.

The super-high contrast agents used in the present invention include:
Any of the above super-high contrast agents may be used as long as they have the performance to achieve the object of the present invention, but hydrazine derivatives are preferably used.

The hydrazine derivative used in the present invention may be any hydrazine derivative as long as it has the performance to achieve the object of the present invention, but those represented by the following formula (H) are preferably used. Can be

[0038]

Embedded image

In the formula, R ² represents an aliphatic group, an aromatic group, or a heterocyclic group, R ¹ represents a hydrogen atom or a block group, and G ¹ represents —CO—, —COCO—, —C (= S)-,-SO
_{2 -, - SO -, -} PO (R 3) - group (. R ³ is selected from the same range as the groups defined in R ^1, may be different from R ^1), or an iminomethylene group . A ¹ and A ^{2 each} represent a hydrogen atom, or one of them represents a hydrogen atom and the other represents a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, or a substituted or unsubstituted acyl group. n1 is 0 or 1,
When n1 is 0, R ¹ represents an aliphatic group, an aromatic group or a heterocyclic group.

In the formula (H), the aliphatic group represented by R ² is preferably a substituted or unsubstituted, straight-chain, branched or cyclic alkyl, alkenyl or alkynyl group having 1 to 30 carbon atoms. .

In the general formula (H), the aromatic group represented by R ² is a monocyclic or condensed-ring aryl group such as a phenyl group derived from a benzene ring or a naphthalene ring,
And a naphthyl group. The heterocyclic group represented by R ² is a monocyclic or condensed, saturated or unsaturated, aromatic or non-aromatic heterocyclic group, and the heterocyclic ring in these groups is, for example, a pyridine ring , Pyrimidine ring, imidazole ring, pyrazole ring, quinoline ring, isoquinoline ring, benzimidazole ring, thiazole ring,
Examples include a benzothiazole ring, a piperidine ring, a triazine ring, a morpholino ring, a piperidine ring, and a piperazine ring.

Preferred as R ² is an aryl group or an alkyl group.

R ² may be substituted. Representative examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), an alkyl group (an aralkyl group, a cycloalkyl group, an active methine group). Alkenyl group, alkynyl group, aryl group, heterocyclic group, heterocyclic group containing a quaternized nitrogen atom (eg, pyridinio group), acyl group, alkoxycarbonyl group,
Aryloxycarbonyl group, carbamoyl group, carboxy group or a salt thereof, sulfonylcarbamoyl group, acylcarbamoyl group, sulfamoylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group, cyano group, thiocarbamoyl group, hydroxy group, alkoxy group ( (Including a group repeatedly containing an ethyleneoxy group or a propyleneoxy group unit), an aryloxy group, a heterocyclic oxy group, an acyloxy group, an (alkoxy or aryloxy) carbonyloxy group, a carbamoyloxy group, a sulfonyloxy group, an amino group, (Alkyl, aryl, or heterocyclic) amino group, N-substituted nitrogen-containing heterocyclic group, acylamino group, sulfonamide group, ureido group, thioureido group, imide group, (alkoxy or aryloxy Carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, quaternary ammonio group, oxamoylamino group, (alkyl or aryl) sulfonyluureido group, acylureido group, acylsulfamoylamino group, A nitro group, a mercapto group, an (alkyl, aryl, or heterocyclic) thio group, an (alkyl or aryl) sulfonyl group, an (alkyl or aryl) sulfinyl group, a sulfo group or a salt thereof, a sulfamoyl group,
An acylsulfamoyl group, a sulfonylsulfamoyl group or a salt thereof, a group having a phosphoric amide or a phosphoric ester structure, and the like can be given.

These substituents may be further substituted with these substituents.

[0045] Preferred examples of the substituent which may be R ² optionally has, when R ² represents an aromatic group or a heterocyclic group, (including an active methylene group) alkyl group, an aralkyl group, a heterocyclic group, Substituted amino group, acylamino group, sulfonamide group, ureido group, sulfamoylamino group,
Imide group, thioureido group, phosphoric amide group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, carboxy group (including its salt), (alkyl , Aryl, or heterocycle)
Examples thereof include a thio group, a sulfo group (including a salt thereof), a sulfamoyl group, a halogen atom, a cyano group, and a nitro group.

When R ² represents an aliphatic group, an alkyl group, an aryl group, a heterocyclic group, an amino group, an acylamino group, a sulfonamide group, a ureido group, a sulfamoylamino group, an imide group, a thioureido group, Phosphoric acid amide group, hydroxy group, alkoxy group, aryloxy group,
Acyloxy group, acyl group, alkoxycarbonyl group,
Aryloxycarbonyl group, carbamoyl group, carboxy group (including its salt), (alkyl, aryl, or heterocycle) thio group, sulfo group (including its salt), sulfamoyl group, halogen atom, cyano group, nitro group, etc. Is preferred.

In the general formula (H), R ¹ represents a hydrogen atom or a block group, and the block group specifically refers to an aliphatic group (specifically, an alkyl group, an alkenyl group, an alkynyl group) or an aromatic group. Group (monocyclic or condensed-ring aryl group), heterocyclic group, alkoxy group, aryloxy group,
Represents an amino group or a hydrazino group.

The alkyl group represented by R ¹ is preferably a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, such as methyl, ethyl, trifluoromethyl, difluoromethyl, 2-carboxytetra. Fluoroethyl group, pyridiniomethyl group, difluoromethoxymethyl group, difluorocarboxymethyl group, 3-hydroxypropyl group, 3-methanesulfonamidopropyl group, phenylsulfonylmethyl group, o-hydroxybenzyl group, methoxymethyl group, phenoxymethyl group, 4
-Ethylphenoxymethyl group, phenylthiomethyl group,
t-butyl group, dicyanomethyl group, diphenylmethyl group,
Examples include a triphenylmethyl group, a methoxycarbonyldiphenylmethyl group, a cyanodiphenylmethyl group, and a methylthiodiphenylmethyl group. The alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms, and examples thereof include a vinyl group, a 2-ethoxycarbonylvinyl group, and a 2-trifluoro-2-methoxycarbonylvinyl group. The alkynyl group preferably has 1 to 10 carbon atoms.
And examples thereof include an ethynyl group and a 2-methoxycarbonylethynyl group. As the aryl group, a monocyclic or condensed-ring aryl group is preferable, and an aryl group containing a benzene ring is particularly preferable. For example, a phenyl group, a perfluorophenyl group, a 3,5-dichlorophenyl group, a 2-methanesulfonamidophenyl group, a 2-carbamoylphenyl group, a 4,5-dicyanophenyl group,
2-hydroxymethylphenyl group, 2,6-dichloro-
Examples include a 4-cyanophenyl group and a 2-chloro-5-octylsulfamoylphenyl group.

The heterocyclic group is preferably a 5- to 6-membered, saturated or unsaturated, monocyclic or condensed heterocyclic group containing at least one of nitrogen, oxygen and sulfur atoms. Morpholino group, piperidino group (N-substituted), imidazolyl group, indazolyl group (4-
Nitroindazolyl group, pyrazolyl group, triazolyl group, benzimidazolyl group, tetrazolyl group, pyridyl group, pyridinio group (N-methyl-3-pyridinio group, etc.), quinolinio group, quinolyl group and the like.

The alkoxy group is preferably an alkoxy group having 1 to 8 carbon atoms, for example, methoxy, 2-hydroxyethoxy, benzyloxy, t-butoxy and the like. As the aryloxy group, a substituted or unsubstituted phenoxy group is preferable, and as the amino group, an unsubstituted amino group, and an alkylamino group having 1 to 10 carbon atoms,
An arylamino group or a saturated or unsaturated heterocyclic amino group (including a nitrogen-containing heterocyclic amino group containing a quaternized nitrogen atom) is preferred. Examples of the amino group include 2,2,6,6-tetramethylpiperidin-4-ylamino group, propylamino group, 2-hydroxyethylamino group, anilino group, o-hydroxyanilino group, 5
-Benzotriazolylamino group, N-benzyl-3-pyridinioamino group and the like. As the hydrazino group, a substituted or unsubstituted hydrazino group or a substituted or unsubstituted phenylhydrazino group (such as a 4-benzenesulfonamidophenylhydrazino group) is particularly preferred.

The group represented by R ¹ may be substituted, and examples of the substituent include those exemplified as the substituent of R ² .

In the general formula (H), R ¹ cleaves the G ¹ -R ¹ moiety from the residual molecule and causes a cyclization reaction to form a cyclic structure containing atoms of the -G ¹ -R ¹ moiety. For example, Japanese Patent Application Laid-Open
No. 29751 and the like.

The hydrazine derivative represented by the general formula (H) may have a built-in adsorptive group that adsorbs to silver halide. Such adsorbing groups include alkylthio, arylthio, thiourea, thioamide,
U.S. Pat. Nos. 4,385,108 and 4,459,347, JP-A-59-195233, JP-A-59-200231, JP-A-59-201045 and JP-A-59-201045, such as mercapto heterocyclic groups and triazole groups. 201046, 5
Nos. 9-201047, 59-201048, 59
-201049, JP-A-61-170733, and 6
1-270744, 62-948, 63-23
No. 4244, No. 63-234245, No. 63-234
No. 246. These adsorbing groups to silver halide may be precursors. As such a precursor, JP-A-2-28
No. 5344.

R ¹ or R ^{2 in} the formula (H) may have a ballast group or a polymer commonly used in immobile photographic additives such as couplers incorporated therein. The ballast group is a group having a carbon number of 8 or more and relatively inactive to photographic properties, such as an alkyl group, an aralkyl group, an alkoxy group, a phenyl group, an alkylphenyl group, a phenoxy group, and an alkylphenoxy group. You can choose from. Examples of the polymer include those described in JP-A-1-100530.

R ¹ or R ² in the general formula (H) may contain a plurality of hydrazino groups as substituents. At this time, the compound represented by the general formula (H) is a polymer having a hydrazino group. Represents, for example, JP-A-64-86134
No., JP-A-4-16938, JP-A-5-97091, WO95-
No. 32452, WO95-32453, Japanese Patent Application No. 7-3511
No. 32, Japanese Patent Application No. 7-351269, Japanese Patent Application No. 7-351168, Japanese Patent Application No. 7-351
Compounds described in Japanese Patent Application No. 351287 and Japanese Patent Application No. 7-351279 are exemplified.

In the general formula (H), R ¹ or R ² represents a cationic group (specifically, a group containing a quaternary ammonium group or a nitrogen-containing hetero atom containing a quaternized nitrogen atom). Ring group), a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, a (alkyl, aryl, or heterocyclic) thio group, or a dissociable group (carboxy group, sulfo group, acylsulfa Moyl group, carbamoylsulfamoyl group, etc.). Examples of those groups include, for example, JP-A-7-234471 and JP-A-5-333466.
JP-A-6-19032, JP-A-6-19031
JP-A-5-45761, U.S. Pat. No. 4,994,365.
No. 4,988,604, JP-A-3-25924.
No. 0, JP-A-7-5610, JP-A-7-244348
And the compounds described in German Patent No. 4006032.

In the general formula (H), A ¹ and A ² represent a hydrogen atom, an alkyl or arylsulfonyl group having 20 or less carbon atoms (preferably a phenylsulfonyl group or a Hammett substituent having a sum of -0.5 or more. Phenylsulfonyl group), an acyl group having 20 or less carbon atoms (preferably a benzoyl group, or a benzoyl group substituted so that the sum of Hammett's substituent constants becomes -0.5 or more, or A chain, branched or cyclic substituted or unsubstituted aliphatic acyl group (here, examples of the substituent include a halogen atom, an ether group, a sulfonamide group, a carbonamide group, a hydroxy group, a carboxy group, a sulfo group, etc. )).

A ¹ and A ² are most preferably hydrogen atoms.

Next, particularly preferred hydrazine derivatives in the present invention will be described.

R ² is preferably a phenyl group or a substituted alkyl group having 1 to 3 carbon atoms.

When R ² represents a phenyl group, preferred substituents are a nitro group, an alkoxy group, an alkyl group, an acylamino group, a ureido group, a sulfonamide group,
Thioureido group, carbamoyl group, sulfamoyl group,
Examples include a carboxy group (or a salt thereof), a sulfo group (or a salt thereof), an alkoxycarbonyl group, or a chloro atom.

When R ² represents a substituted phenyl group, the substituent may be directly or via a linking group, a ballast group, an adsorptive group to silver halide, a group containing a quaternary ammonium group, or a quaternized group. Nitrogen-containing heterocyclic group containing a nitrogen atom, a group containing a repeating unit of an ethyleneoxy group, an (alkyl, aryl, or heterocyclic) thio group, a nitro group, an alkoxy group, an acylamino group, a sulfonamide group, a dissociative group ( carboxy group, sulfo group, acylsulfamoyl group, such as carbamoyl sulfamoyl group), or at least one hydrazino group capable of forming a multimer (group represented by -NHNH-G ¹ -R ¹⁾ is substituted Is more preferable.

[0063] When R ² represents a substituted alkyl group having 1 to 3 carbon atoms, R ² is more preferably a substituted methyl group, more preferably a disubstituted methyl group or trisubstituted methyl group, as a substituent Are specifically a methyl group, a phenyl group, a cyano group, an (alkyl, aryl or heterocycle) thio group, an alkoxy group, an aryloxy group, a chloro atom, a heterocyclic group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl A group, a sulfamoyl group, an amino group, an acylamino group, or a sulfonamide group is preferred, and a substituted or unsubstituted phenyl group is particularly preferred.

When R ² represents a substituted methyl group, more preferred specific examples are t-butyl group, dicyanomethyl group, dicyanophenylmethyl group, triphenylmethyl group (trityl group), diphenylmethyl group, methoxycarbonyldiphenyl Examples include a methyl group, a cyanodiphenylmethyl group, a methylthiodiphenylmethyl group, a cyclopropyldiphenylmethyl group, and among them, a trityl group is most preferred.

In the general formula (H), R ² is most preferably a substituted phenyl group.

[0066] While in n1 general formula (H) represents 1 or 0, when n1 is 0, R ¹ represents an aliphatic group, an aromatic group or a heterocyclic group. When n1 is 0, R ¹ is particularly preferably a phenyl group or a substituted alkyl group having 1 to 3 carbon atoms, which is the same as the preferable ranges of R ² described above.

N1 is preferably 1.

Among the groups represented by R ¹ , when R ² represents a phenyl group and G ¹ is —CO—, a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, Or a heterocyclic group, more preferably a hydrogen atom, an alkyl group, or an aryl group, and most preferably a hydrogen atom or an alkyl group. Here, when R ¹ represents an alkyl group, the substituent is particularly preferably a halogen atom, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, or a carboxy group.

R ² represents a substituted methyl group, and G ¹ represents-
In the case of CO-, R ¹ is preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an amino group (unsubstituted amino group, alkylamino group, arylamino group, heterocyclic amino group). And more preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an alkylamino group, an arylamino group, or a heterocyclic amino group. When G ¹ is —COCO—, R ²
Regardless, R ¹ is an alkoxy group, an aryloxy group,
An amino group is preferred, and a substituted amino group, specifically an alkylamino group, an arylamino group, or a saturated or unsaturated heterocyclic amino group is particularly preferred.

When G ¹ is —SO ₂ —, R ¹ is preferably an alkyl group, an aryl group or a substituted amino group regardless of R ² .

In the general formula (H), G ¹ is preferably-
CO- or -COCO-, particularly preferably -C
O-.

Next, specific examples of the compound represented by formula (H) are shown below. However, the present invention is not limited to the following compounds.

[0073]

[Table 1]

[0074]

[Table 2]

[0075]

[Table 3]

[0076]

[Table 4]

[0077]

[Table 5]

[0078]

[Table 6]

[0079]

[Table 7]

[0080]

[Table 8]

[0081]

[Table 9]

[0082]

[Table 10]

[0083]

[Table 11]

[0084]

[Table 12]

[0085]

[Table 13]

[0086]

[Table 14]

[0087]

[Table 15]

[0088]

[Table 16]

[0089]

[Table 17]

[0090]

[Table 18]

[0091]

[Table 19]

[0092]

[Table 20]

The compound represented by formula (H) may be used alone or in combination of two or more.

As the hydrazine derivative used in the present invention, in addition to the above, the following hydrazine derivatives are preferably used. (In some cases, they can be used in combination.) The hydrazine derivative used in the present invention can also be obtained by various methods described in the following patents.
Can be synthesized.

(Formula 1) described in JP-B-6-77138
And specifically the compounds described on pages 3 and 4 of the same publication. A compound represented by the general formula (I) described in JP-B-6-93082, specifically, pages 8 to 1 of the publication
Compounds 1 to 38 on page 8. JP-A-6-23049
A compound represented by the general formula (4), the general formula (5) or the general formula (6) described in No. 7;
Compounds 4-1 to 4-10 described on page 26, compounds 5-1 to 5-42 described on pages 28 to 36, and 39
6-1 to 6-7. Compounds represented by the general formulas (1) and (2) described in JP-A-6-289520, specifically from page 5 to
Compounds 1-1) to 1-17) and 2-
1). Compounds represented by (Chemical Formula 2) and (Chemical Formula 3) described in JP-A-6-313936, specifically, compounds described on pages 6 to 19 of the same. Compounds represented by (Chemical Formula 1) described in JP-A-6-313951, specifically, compounds described on pages 3 to 5 of the same. Compounds represented by formula (I) described in JP-A-7-5610, specifically, compounds I-1 to I-38 described on pages 5 to 10 of the same. Compounds represented by the general formula (II) described in JP-A-7-77783, specifically, compounds II-1 to II-102 described on pages 10 to 27 of the same. Compounds represented by general formula (H) and general formula (Ha) described in JP-A-7-104426, specifically, compound H described on pages 8 to 15 of the same publication
-1 to H-44. As described in Japanese Patent Application No. 7-191007,
A compound characterized by having an anionic group or a nonionic group forming an intramolecular hydrogen bond with a hydrogen atom of hydrazine in the vicinity of a hydrazine group. C), compounds represented by formulas (D), (E), and (F), specifically, compounds N-1 to N-30 described in the same specification. Japanese Patent Application No. 7-
The compound represented by the general formula (1) described in JP191007, specifically, the compounds D-1 to D-5 described in the same specification
5.

Further, “Known techniques (1 to
207) ”(published by Aztec) on pages 25 to 34. Compounds D-2 and D-39 of JP-A-62-86354 (pages 6 to 7).

The hydrazine-based nucleating agent of the present invention can be used in a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethyl sulfoxide, methyl cellosolve and the like. Can be dissolved and used.

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

The hydrazine nucleating agent of the present invention may be added to a silver halide emulsion layer which is a layer on the side of the silver halide emulsion layer which is an image forming layer with respect to the support or any other layer. It is preferably added to the silver halide emulsion layer or a layer adjacent thereto.

The amount of the nucleating agent added in the present invention is 1 silver halide.
It is preferably 1 × 10 ⁻⁶ to 1 × 10 ⁻² mol per mol,
× 10 ^{-5 to} 5 × 10 ^-3 mol is more preferred, and 2 × 10 ^-5
~ 5 x ^10-3 mol is most preferred.

The photothermographic material of the present invention is preferably a photothermographic material containing photosensitive silver halide as a photocatalyst.

The method of forming the photosensitive silver halide in the present invention is well known in the art, and uses, for example, the methods described in Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458. be able to. 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 particle size of the photosensitive silver halide is preferably small for the purpose of suppressing the white turbidity after image formation to be low.
20 μm or less, more preferably 0.01 μm or more and 0.15 μm or less,
More preferably, the thickness is 0.02 μm or more and 0.12 μm or less. 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-shaped grains, etc., it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

The shapes of the silver halide grains are 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 ratio of {100} plane was determined by T. Tani; J. Imaging Sci., 29, 165 (1985) using the dependence of adsorption of sensitizing dyes on {111} and {100} planes. It can be determined by the method described. The halogen composition of the photosensitive silver halide is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, and silver iodide. In the present invention, silver bromide,
Alternatively, silver iodobromide can be preferably used. Particularly preferred is silver iodobromide, and the silver iodide content is 0.1%.
Mol% or more and 40 mol% or less are preferable, and 0.1 mol% or more and 20 mol
% Or less is more preferable. The distribution of the halogen composition in the grains may be uniform, the halogen composition may be changed stepwise, or may be changed continuously, but as a preferable example, the silver iodide content inside the grains is High silver iodobromide grains can be used. Preferably, silver halide grains having a core / shell structure can be used. The structure is preferably 2
Core / shell particles having a ５5-fold structure, more preferably a 2- to 4-fold structure, can be used.

The photosensitive silver halide grains of the present invention preferably contain at least one complex of a metal selected from rhodium, rhenium, ruthenium, osmium, iridium, cobalt and iron. These metal complexes are 1
They may be of the same kind, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol per mol of silver,
A range of 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol is more preferable. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used.
As the compound of cobalt and iron, a hexacyano metal complex can be preferably used. Specific examples include ferricyanate ion, ferrocyanate ion, hexacyanocobaltate ion, and the like, but are not limited thereto. The metal complex in the silver halide may be contained uniformly, may be contained in the core at a high concentration, or may be contained in the shell at a high concentration, and there is no particular limitation.

The photosensitive silver halide grains can be desalted by washing with a method known in the art such as a noodle method or a flocculation method, but in the present invention, they may or may not be desalted. .

The photosensitive silver halide grains in the present invention are preferably chemically sensitized. As a preferred chemical sensitization method, a sulfur sensitization method, a selenium sensitization method, and a tellurium sensitization method are well known in the art. Further, a noble metal sensitization method or a reduction sensitization method of a gold compound, platinum, palladium, an iridium compound or the like can be used. As the compound preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds can be used, and the compounds described in JP-A-7-128768 can be used. 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, P-Te
Compounds having a bond, Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Compounds preferably used for the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, or U.S. Pat.
Compounds described in 18,061 and the like can be preferably 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. . Reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ion during grain formation.

The amount of the photosensitive silver halide used in the present invention is preferably from 0.01 mol to 0.5 mol, more preferably from 0.02 mol to 0.3 mol, more preferably from 0.03 mol to 0.3 mol, per mol of the organic silver salt. It is particularly preferably at least 0.25 mol and not more than 0.25 mol. 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 are mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. There is a method of mixing, 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 the effects of the present invention are sufficiently exhibited.

In the present invention, a reducible silver salt is used.
Organic silver salts that can be used as reducible silver salts include:
Relatively stable to light, but forms a silver image when heated to 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent It is a silver salt. The organic silver salt can be any organic substance including a source capable of reducing silver ions. Silver salts of organic acids,
Particularly, a silver salt of a long-chain fatty carboxylic acid (having 10 to 30 carbon atoms, preferably 15 to 28 carbon atoms) is preferred. Complexes of organic or inorganic silver salts wherein the ligand has a complex stability constant in the range of 4.0 to 10.0 are also preferred. The silver donor is preferably present in about 5 to 3 of the image forming layer.
0% by weight can be constituted. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate, silver fumarate, and tartaric acid. Silver, silver linoleate, silver butyrate and silver camphorate, and mixtures thereof.

A silver salt of a compound containing a mercapto group or a thione group and derivatives thereof can also be used.
Preferred examples of these compounds include 3-mercapto-4
-Phenyl-1,2,4-triazole silver salt, 2-mercaptobenzimidazole silver salt, 2-mercapto-5-aminothiadiazole silver salt, 2- (ethylglycolamide) benzothiazole silver salt, S- Silver salts of thioglycolic acid such as silver salts of 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, 5 -Carboxyl-1-methyl-2-phenyl-4-thiopyridine silver salt, mercaptotriazine silver salt, 2-mercaptobenzoxazole silver salt, silver salts described in U.S. Pat.No.4,123,274, for example, 3-amino-5 Silver salts of 1,2,4-mercaptothiazole derivatives such as -benzylthio-1,2,4-thiazole silver salt, 3- (3-carboxyethyl) -4- described in U.S. Pat.No. 3,301,678
Includes silver salts of thione compounds such as silver salt of methyl-4-thiazoline-2-thione. Further, compounds containing an imino group can 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, U.S. Pat.
0,709 1,2,4-triazole or 1-H-
Includes silver salts of tetrazole, silver salts of imidazole and imidazole derivatives, and the like. For example, U.S. Pat.
Various silver acetylide compounds as described in No. 1 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. As is well known in photosensitive silver halide light-sensitive materials, the inverse relationship between the size of silver salt crystal grains and their covering power also holds in the photothermographic material of the present invention, that is, the photothermographic material When the size of the organic silver salt particles in the image forming section is large, it means that the covering power is small and the image density is low. Therefore, it is necessary to reduce the size of the organic silver salt. In the present invention, short axis 0.01μ
m or more and 0.20 μm or less, major axis 0.10 μm or more and 5.0 μm or less, minor axis 0.01 μm or more and 0.15 μm or less, major axis 0.10 μm or more
4.0 μm or less is more preferable. The particle size distribution of the organic silver salt is preferably monodispersed. Monodispersion is the minor axis, the percentage of the value obtained by dividing the standard deviation of the length of each major axis by each minor axis, major axis is preferably 100% or less, more preferably 80% or less.
%, More preferably 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. Another method for measuring monodispersity is to determine the standard deviation of the volume-weighted average diameter of the organic silver salt, and the percentage 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 50% or less. As a measuring method, for example, the particle size (volume weighted average diameter) obtained by irradiating a laser beam to an organic silver salt dispersed in a liquid and obtaining an autocorrelation function with respect to a time change of fluctuation of the scattered light is obtained. Can be.

As the sensitizing dye in the present invention, any dye can be used as long as it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holopolar cyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye, and the like can be used. Useful sensitizing dyes for use in the present invention include, for example, RESEARCH DISCLOSURE Item 17
Item 643IV-A (p.23, December 1978), Item 1831X (August 1979)
p.437) or in the literature cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers, scanners, imagesetters and plate making cameras can be advantageously selected.

Examples of spectral sensitization to red light include He-Ne
For the laser light source, I- described in JP-A-54-18726
Compounds 1 to I-38, I-1 to I described in JP-A-6-75322
-35 and I-1 to I- described in JP-A-7-287338.
Compound 34, dyes 1 to 20 described in JP-B-55-39818, and I-1 to I described in JP-A-62-284343 for LED light sources
-37 and I-1 to I- described in JP-A-7-287338.
34 compounds and the like are advantageously selected.

The silver halide grains are spectrally sensitized in any wavelength range from 750 to 1400 nm. Specifically, the photosensitive silver halide can be spectrally sensitized with various known dyes, including cyanine, merocyanine, styryl, hemicyanine, oxonol, hemioxonol, and xanthene dyes. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nuclei, oxazoline nuclei, pyrroline nuclei, pyridine nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei and imidazole nuclei. 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 cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Pat.
No. 3,719,495, No. 3,877,943, British Patent No. 1,
No. 466,201, No. 1,469,117, No. 1,422,057, Japanese Patent Publication No. 3-10391, Japanese Patent Publication No. 6-52387, JP-A-5-341432, JP-A-6-194781, and JP-A-6-301141. Such dyes may be appropriately selected from known dyes. A particularly preferred structure of the dye is a cyanine dye having a thioether bond, and examples thereof include JP-A-62-58239 and JP-A-3-13.
No. 8638, No. 3-138842, No. 42-558840, No. 5-72659,
5-72661, 6-222491, 2-230506, 6-25875
Cyanine dyes described in JP-A No. 7, 6-317868, 6-324425, and JP-T-Hei 7-500926.

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. Along with 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
Research Disclosure Volume 176, 17643 (December 1978) No. 23
It is described in page IV, section J, or JP-B-49-25500, JP-B-43-4933, JP-A-59-19032, and JP-A-59-192242.

The sensitizing dyes used in the present invention may be used in combination of two or more. To add sensitizing dyes to a silver halide emulsion, they may be directly dispersed in the emulsion,
Or water, methanol, ethanol, propanol,
Acetone, methyl cellosolve, 2,2,3,3-tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol , N, N-dimethylformamide or the like, alone or in a mixed solvent, and added to the emulsion.

As disclosed in US Pat. No. 3,469,987, a dye is dissolved in a volatile organic solvent, and this solution is dispersed in water or a hydrophilic colloid. Method of adding into the inside, Japanese Patent Publication No. 44-23389,
As disclosed in JP-A-44-27555 and JP-A-57-22091, the dye is dissolved in an acid and this solution is added to the emulsion, or an acid or base is added to the emulsion as an aqueous solution in the presence of an acid or base. A method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to an emulsion as disclosed in U.S. Patent Nos. 3,822,135 and 4,006,025, -102733, 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, JP-A-51-7
As disclosed in Japanese Patent No. 4624, a method of dissolving a dye using a compound that causes a red shift and adding this solution to an emulsion can also be used. Also, ultrasonic waves can be used for dissolution.

The sensitizing dye used in the present invention may be added to the silver halide emulsion at any time during the preparation of the emulsion which has been found to be useful.
For example, U.S. Pat.Nos. 2,735,766, 3,628,960,
No. 4,183,756, No. 4,225,666, JP-A-58-184142,
As disclosed in the specification of JP-A-60-196749 and the like, the timing before silver halide grain forming step and / or desalting, during and / or after desalting and before the start of chemical ripening. As disclosed in the specification such as JP-A-58-113920, any time immediately before chemical ripening or during the process, after chemical ripening, and before coating the emulsion before coating It may be added at the time and in the process.
As disclosed in U.S. Pat. No. 4,225,666 and Japanese Patent Application Laid-Open No. 58-7629, the same compound may be used alone or in combination with a compound having a different structure, for example, in a particle forming step. It may be divided and added separately during or after the chemical ripening step or during the chemical ripening step, or may be added separately before or during the chemical ripening step and after the completion of the chemical ripening step. You may change and add the kind of combination.

In the present invention, a reducing agent is used. The reducing agent for the organic silver salt may be any substance that reduces silver ions to metallic silver, preferably an organic substance. Phenidone,
Conventional photographic developers such as hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred. The reducing agent should be present as 1 to 10% by weight of the imaging layer. In multilayer constructions, if the reducing agent is added to a layer other than the emulsion layer, a slightly higher percentage
2-15% by weight tends to be more desirable.

A wide range of reducing agents have been disclosed for photothermographic materials utilizing organic silver salts. For example, phenylamide oxime, 2-thienylamide oxime and p-
Amide oximes such as phenoxyphenylamide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; such as the combination of 2,2′-bis (hydroxymethyl) propionyl-β-phenylhydrazine and ascorbic acid A combination of an aliphatic carboxylic acid aryl hydrazide and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (for example, hydroquinone and bis (ethoxyethyl) hydroxylamine, piperidinohexose reductone or formyl) 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-
Diones and the like; chromanes such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman; 1,4-dihydropyridines such as 2,6-dimethoxy-3,5-dicarboethoxy-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 and the like); ascorbic acid derivatives (for example, palmitic acid 1 -Ascorbyl, ascorbyl stearate, etc.); and aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indan-1,3-diones.

Particularly preferred reducing agents in the present invention include compounds represented by the following general formulas (RI), (R-II), (R-III) and (R-IV). No.

[0121]

Embedded image

In the general formula (R-III), the ring structure formed by Z is as follows.

[0123]

Embedded image

In the general formula (R-IV), the ring structure formed by Z is as follows.

[0125]

Embedded image

In the formula, L ₁ and L ₂ represent CH—R ₆ , CH—
A group represented by R ₆ ′ or a sulfur atom; n represents a natural number.

R _i (R _{1 to} R ₁₀ , R ₁ ′ to R ₅ ′, R ₆ ′,
_{R 11 ~R 13, R 11 '} ~R 13', R 21 ~R 26, R 21 '~R
₂₄ ′) is a hydrogen atom, an alkyl group (1 to 30 carbon atoms), an aryl group, an aralkyl group, a halogen atom, an amino group or a substituent represented by —OA. Provided that at least one of R _{1 to} R ₅ and Z ¹ ′ to
At least one of R ₅ ′ and at least one of R _{7 to} R ₁₀
One is a group represented by -OA. Also, R _i may form a ring. A and A 'represent a hydrogen atom, an alkyl group (1 to 30 carbon atoms), an acyl group (1 to 30 carbon atoms), an aryl group, a phosphoric acid group, and a sulfonyl group. R _i , A,
A ′ may be substituted, and typical examples of the substituent include an alkyl group (including an active methylene group), a nitro group, an alkenyl group, an alkynyl group, an aryl group, a group including a heterocyclic ring, and a quaternary group. A group containing a heterocyclic ring containing a converted nitrogen atom (eg, a pyridinio group), a hydroxy group, an alkoxy group (including a group repeatedly containing an ethyleneoxy group or a propyleneoxy group unit), an aryloxy group,
Acyloxy group, acyl group, alkoxycarbonyl group,
Arylcarbonyl group, carbamoyl group, urethane group,
Carboxy group, imide group, amino group, carbonamide group, sulfonamide group, ureide group, thioureide group,
Sulfamoylamino group, semicarbazide group, thiosemicarbazide group, group containing hydrazino group, group containing quaternary ammonium group, mercapto group, (alkyl, aryl or heterocycle) thio group, (alkyl or aryl) sulfonyl group , (Alkyl or aryl) sulfinyl group, sulfo group, sulfamoyl group, acylsulfamoyl group, (alkyl or aryl) sulfonylureido group, (alkyl or aryl) sulfonylcarbamoyl group, halogen atom, cyano group, phosphoramide group,
Examples include a group having a phosphate ester structure, a group having an acylurea structure, a group having a selenium atom or a tellurium atom, and a group having a tertiary sulfonium structure or a quaternary sulfonium structure. The substituents of R _i , A and A ′ may be further substituted, and preferred examples include those exemplified as the substituents of R _i . A substituent, a substituent of the substituent, a substituent of the substituent of the substituent. . . The compound may be substituted multiple times as described above, and preferable examples also include those exemplified as the substituents of R _i , A and A ′.

Hereinafter, the compounds represented by the general formulas (RI) and (R-
II), and specific examples of the compounds represented by the general formula (R-III) and the general formula (R-IV). However, the present invention is not limited to the following compounds.

[0129]

[Table 21]

[0130]

[Table 22]

[0131]

Embedded image

[0132]

[Table 23]

[0133]

[Table 24]

[0134]

[Table 25]

[0135]

[Table 26]

[0136]

[Table 27]

The amount of the reducing agent used in the present invention is preferably 1 × 10 ⁻³ to 10 mol, more preferably 1 × 10 ^{−2 to} 1.5 mol, per 1 mol of silver. is there.

In the present invention, a mercapto compound or a thione compound can be contained in order to control the development by suppressing or accelerating the development, to improve the spectral sensitization efficiency, or to improve the storage stability before and after the development. .

When a mercapto compound is used in the present invention, it may have any structure, but is preferably a compound represented by Ar-SM. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring group or a condensed aromatic ring group having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, a heteroaromatic ring group, wherein the heteroaromatic ring in these groups 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) and alkoxy ( For example, it may have a substituent selected from the group consisting of one or more carbon atoms, preferably those having 1 to 4 carbon atoms. As mercapto-substituted heteroaromatic compounds, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole, 2,2 '-Dithiobis-benzothiazole, 3-mercapto-1,2,4-triazole, 4,5-diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-
4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,
2,4-Triazole, 4-Hydrocyr-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl- Examples thereof include 1,2,4-triazole and 2-mercapto-4-phenyloxazole, but the present invention is not limited thereto.

The addition amount of these mercapto compounds is preferably in the range of 1 × 10 ⁻⁶ to 1 mol per mol of silver in the emulsion layer, and more preferably 1 × 10 ⁻⁶ to 1 mol per mol of silver.
10 ^- is the amount of ^{from 3} to 0.3 moles.

It may be advantageous to include additives known as "toning agents" which enhance the image. For example, the toning material may be present in an amount of 0.1 to 10% by weight of the total silver holding component. Toning agents are described in U.S. Pat.Nos. 3,080,254 and 3,847,612.
Nos. 4,123,282 and 4,123,282.

Examples of toning agents include phthalimide and N-hydroxyphthalimide; succinimide, pyrazoline-5-
On, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and
Cyclic imides such as 2,4-thiazolidinedione; naphthalimides (eg, N-hydroxy-1,8-naphthalimide);
Cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4-triazole,
4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,
Mercaptans exemplified by 4-thiadiazole; N- (aminomethyl) aryldicarboximide, (for example, (N, N
-Dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-dicarboximide); and blocked pyrazoles, isothiuronium derivatives and certain photobleaching agents (e.g., 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, a phthalazinone derivative or a metal salt, or 4- (1
-Naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-
Derivatives such as dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione; phthalazinone and phthalic acid derivatives (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride) A phthalazine, a phthalazine derivative or a metal salt,
Or derivatives such as 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (for example, phthalic acid, 4-methylphthalic acid) Quinazolinedione, benzoxazine or naphthoxazine derivatives; not only as a color tone regulator but also as a source of halide ions for silver halide formation in situ. A working rhodium complex, such as hexachlororhodium (III)
Ammonium phosphate, rhodium bromide, rhodium nitrate and potassium hexachlororhodate (III) and the like; inorganic peroxides and persulfates such as ammonium disulfide and hydrogen peroxide; 1,3-benzoxazine-2,4 Benzoxazine-2,4-diones such as -dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione; pyrimidine and non-pyrimidine Asymmetric-triazines (e.g., 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (e.g., 3,6-dimercapto-1,4-diphenyl-1H, 4H -2,3a, 5,6a-tetraazapentalene and 1,4-di (o-chlorophenyl) -3,6-dimercapto-1H, 4H-2,3a, 5,6a-tetraazapentalene) There is.

As the binder for the emulsion layer in the present invention, well-known natural or synthetic resins such as gelatin, polyvinyl acetal, polyvinyl chloride,
Any one can be selected from polyvinyl acetate, cellulose acetate, polyolefin, polyester, polystyrene, polyacrylonitrile, polycarbonate and the like. Of course, copolymers and terpolymers are also included. Preferred polymers are polyvinyl butyral, butyl ethyl cellulose, methacrylate copolymer, maleic anhydride copolymer, polystyrene and butadiene-styrene copolymer. If necessary, two or more of these polymers can be used in combination. Such a polymer is used in an amount sufficient to hold the components therein. That is, it is used in a range effective to function as a binder. The effective range can be appropriately determined by those skilled in the art. As a guideline for at least retaining the organic silver salt, the ratio of the binder to the organic silver salt is 15:
A range of 1 to 1: 2, especially 8: 1 to 1: 1 is preferred.

At least one of the image forming layers (ie, emulsion layers) of the present invention may be an image forming layer using 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 “emulsion layer”). The polymer latex used in the "image forming layer of the present invention" and the binder is referred to as "the polymer latex of the present invention"). 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 of the present invention, `` Synthetic resin emulsion (Hiroshi Okuda, edited by Hiroshi Inagaki, published by the Society of Polymer Publishing (1978)) '', `` Application of synthetic latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, edited by Keiji Kasahara, Published by Polymer Publishing Association (1
993)) "," 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 they may have a wide particle size distribution or a monodispersed particle size distribution.

As the polymer latex of the present invention, other than a polymer latex having a normal uniform structure, a so-called core / polymer latex is used.
Shell type latex may be used. In this case, it may be preferable to change the glass transition temperature of the core and the shell.

The minimum film forming temperature (MFT) of the polymer latex of the present invention is preferably from -30 ° C to 90 ° C, more preferably from about 0 ° C to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. The film-forming aid is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of the polymer latex, also called a plasticizer. )"It is described in.

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

The polymer of the polymer latex used in the present invention preferably has an equilibrium water content at 25 ° C. and 60% RH of 2% by weight or less, more preferably 1% by weight or less. The lower limit of the equilibrium water content is not particularly limited, but is preferably 0.01% by weight, more preferably 0.03% by weight. For the definition and measurement method of the equilibrium moisture content, see, for example, “Polymer Engineering Course 14, Polymer Material Testing Method (Polymer Society, edited by Jinjinshokan)”
And so on.

Specific examples of the polymer latex used as a binder in the image forming layer of the photothermographic material of the present invention are as follows. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer, latex of styrene / butadiene / acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer Latex of methyl methacrylate / vinyl chloride / acrylic acid copolymer, latex of vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer, and the like.
Such polymers are also commercially available, and the following polymers can be used. For example, as examples of acrylic resin, Sebian A-4635,46583,4601 (all manufactured by Daicel Chemical Industries, Ltd.), Nipol Lx811,814,821,820,857
(Nippon Zeon Co., Ltd.) and other polyester resins, such as FINETEX ES650, 611, 675, 850 (Dai Nippon Ink Chemical Co., Ltd.), WD-size, WMS (Eastman Chemical Co., Ltd.), etc. HYDRAN AP10 as polyurethane resin,
LACSTAR 7310K, 3307B, 4700H, 7132C as rubber resins such as 20, 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.)
(Dai Nippon Ink Chemical Co., Ltd.), Nipol Lx416, 41
0, 438C, 2507, (Nippon Zeon Co., Ltd.) and other vinyl chloride resins such as G351 and G576 (Nippon Zeon Co., Ltd.)
Examples of the vinylidene chloride resin include L502 and L513 (all manufactured by Asahi Kasei Kogyo Co., Ltd.), and olefin resins include Chemipearl S120 and SA100 (all manufactured by Mitsui Petrochemical Co., Ltd.). These polymers may be used alone or as a blend of two or more as necessary.

In such a case, the above-mentioned polymer latex may be used in the image forming layer in an amount of 50% by weight or more of the entire binder, and preferably 70% by weight or more of the polymer latex.

In the image forming layer of the present invention, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose and hydroxypropylmethylcellulose may be added to the binder in an amount of 50% by weight or less based on the whole binder. Is also good. The addition amount of these hydrophilic polymers is preferably 30% by weight or less of the total binder in the image forming layer.

The image forming layer of the present invention can be prepared by applying an aqueous coating solution and then drying. However, the term “aqueous” used herein means that 30% 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%.)

Further, the method described in US Pat. No. 5,946,955 can also be used.

The total amount of the binder in the image forming layer of the present invention is 0.1.
The range is preferably ^{2 to} 30 g / m ² , more preferably 1 to 15 g / m ² . A crosslinking agent for crosslinking may be added to the image forming layer of the invention.

In the heat-developable photographic material of the present invention, a surface protective layer can be provided for the purpose of preventing adhesion of an image forming layer (emulsion layer, photosensitive layer, etc.). 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.

In the emulsion layer or the protective layer of the emulsion layer in the invention, US Pat. Nos. 3,253,921 and 2,274,782,
Light absorbing materials and filter dyes as described in US Pat. Nos. 2,527,583 and 2,956,879 can be used. Also, dyes can be mordanted, for example, as described in US Pat. No. 3,282,699.

In the emulsion layer or the protective layer of the emulsion layer in the present invention, a matting agent such as starch, titanium dioxide, zinc oxide, silica, US Pat. Nos. 2,992,101 and 2,7
Polymer beads, including beads of the type described in JP 01,245, can be included. The matte degree of the emulsion surface may be any value as long as stardust failure does not occur, but the Beck smoothness is preferably 1,000 seconds or more and 10,000 seconds or less, particularly 200
The time is preferably from 0 to 10,000 seconds.

In the present invention, the silver halide emulsion or /
And 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.Nos. 2,886,437 and 2,444,605. Azaindene, U.S. Pat.
8,663 mercury salt, U.S. Pat.No. 3,287,135 urazole, U.S. Pat.No. 3,235,652 sulfocatechol, British Patent 623,448 Oxime,
Nitrone, nitroindazole, U.S. Patent No. 2,839,405
No. 3,220,839, thiuronium salts, and U.S. Pat.Nos. 2,566,263 and 2,597,915, palladium, platinum and gold salts, U.S. Pat.Nos. 4,108,665 and 4,442,202 No. 4,128,557
Nos. 4,137,079 and 4,138,365 and 4,
No. 4,59,350 and U.S. Pat.
And the phosphorus compounds described in No. 1,985.

In the emulsion layer of the present invention, a polyhydric alcohol (for example, US Pat.
Glycerin and diols of the type described in U.S. Pat. No. 0,404), 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.

A hardener may be used in each of the layers such as the emulsion layer, the protective layer, and the back layer of the present invention. Examples of hardeners include U.S. Pat.No. 4,281,060, polyisocyanates described in JP-A-6-208193, epoxy compounds described in U.S. Pat.No. 4,791,042, and JP-A-62-89048.
And vinylsulfone compounds described in Nos. 1 and 2 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,
No. 62-170950, Fluoropolymer surfactants described in U.S. Pat.No. 5,382,504, JP-A-60-244945, JP-A-63-18
8135 No. fluorinated surfactants described in U.S. Pat.
No. 5,965, and the like, and polysiloxy acid-based surfactants described in JP-A-6-301140 and the like, and polyalkylene oxide and anionic surfactants.

The heat-developable photographic emulsion of the present invention can be 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 Including materials, as well as glass, paper, metal and the like. Coated with a flexible substrate, especially baryta paper, or a partially acetylated α-olefin polymer, especially a polymer of α-olefin having 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylene-butene copolymer. A paper support is typically used.
The support may be transparent or opaque, but is preferably transparent.

The photographic material of the present invention comprises an antistatic or conductive layer such as a soluble salt (eg, chloride, nitrate, etc.), a vapor-deposited metal layer, US Pat. No. 2,861,056 and US Pat.
It may have a layer containing an ionic polymer as described in US Pat. No. 3,206,312 or an insoluble inorganic salt as described in US Pat. No. 3,428,451.

As a method for obtaining a color image using the heat-developable photographic material in the present invention, JP-A-7-13295, page 10, left column 4
There is a method described from the third line to the 11th left column, 40th line. Also, as a stabilizer for color dye images, UK Patent No. 1,326,889
No. 3,432,300, U.S. Pat.No. 3,698,909, U.S. Pat.
Nos. 574,627, 3,573,050, 3,764,337 and 4,042,394.

The photothermographic emulsions of the present invention can be coated by various coating operations including dip coating, air knife coating, flow coating or extrusion coating using a hopper of the type described in 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 heat-developable photographic material of the present invention, additional layers, such as a dye-receiving layer for receiving a mobile dye image, an opaque layer if reflective printing is desired, a protective topcoat layer and photothermographic techniques It may include a known primer layer and the like. The photographic material of the present invention is preferably capable of forming an image with only one photographic material, and it is preferable that a functional layer required for image formation such as an image receiving layer does not become a photographic material.

The vinylidene chloride copolymer in the present invention is a copolymer containing 50 to 99.9% by weight, preferably 70 to 99% by weight, of vinylidene chloride.
Vinylidene chloride / acrylates described in 35526 /
A copolymer comprising a vinylidene monomer having an alcohol in a side chain, vinylidene chloride described in US Pat. No. 2,852,378;
A copolymer comprising an alkyl acrylate / acrylic acid,
US Pat. No. 2,698,235 describes a copolymer of vinylidene chloride / acrylonitrile / itaconic acid, US Pat.
Copolymers of vinylidene chloride / alkyl acrylate / itaconic acid described in No. 8,856 and the like can be mentioned. Specific examples of the compounds are shown below, but the present invention is not limited thereto. The numbers in parentheses indicate weight ratios.

Copolymer of vinylidene chloride: methyl acrylate: hydroxyethyl acrylate (83: 12: 5) Vinylidene chloride: hydroxyethyl methacrylate: copolymer of hydroxypropyl acrylate (82: 10: 8) Vinylidene chloride: hydroxydiethyl methacrylate (9
2: 8) copolymer vinylidene chloride: butyl acrylate: acrylic acid (9
4: 4: 2) copolymer vinylidene chloride: butyl acrylate: itaconic acid (7
5: 20: 5) copolymer vinylidene chloride: methyl acrylate: itaconic acid (9
0: 8: 2) copolymer vinylidene chloride: itaconic acid monoethyl ester (96:
4) Copolymer of vinylidene chloride: acrylonitrile: acrylic acid (96:
3.5: 1.5) copolymer vinylidene chloride: methyl acrylate: acrylic acid (9
2: 5: 3) Copolymer of vinylidene chloride: methyl acrylate: 3-chloro-2-hydroxypropyl acrylate (84: 9: 7) Copolymer of vinylidene chloride: methyl acrylate: N-ethanol acrylamide (85:10) : Copolymer of 5)

The method of applying the vinylidene chloride copolymer in the present invention may be carried out by a dip coating method, an air knife method, or the like, in which a liquid obtained by dissolving a polymer in a suitable organic solvent or a liquid dispersed in water is used. Coating method, curtain coating method, roller coating method, wire bar coating method, gravure coating method, or US Patent 2,681,294
It can be applied by an extrusion coating method using a hopper described in No. It is also possible to use a so-called extrusion coating method in which a molten polymer is caused to flow down onto a moving object to be applied and to be bonded by pressure simultaneously with cooling, or a lamination method in which a polymer in a film form is bonded with a paste and heat. Good.

The heat-developable photographic material of the present invention has at least one photosensitive layer (emulsion layer) containing a silver halide emulsion which is an image forming layer on one side of a support, and on the other side. It is preferably a so-called one-sided photosensitive material having a backing layer (back layer).

In the present invention, a matting agent may be added for improving transportability. The matting agent is generally fine particles of an organic or inorganic compound insoluble in water. Any matting agent can be used, for example, U.S. Pat.
No. 213, No. 2,701,245, No. 2,322,037, No. 3,262,782
Nos. 3,539,344, 3,767,448, 3,767,448, etc., the organic matting agents described in the respective specifications, 1,260,772, 2,192,241, and 3,300
257,206, 3,370,951, 3,523,022, 3,769,0
Those well known in the art, such as an inorganic matting agent described in each specification such as No. 20, can be used. For example, specifically, examples of organic compounds that can be used as a matting agent include, as examples of water-dispersible vinyl polymers, polymethyl acrylate, polymethyl methacrylate, polyacrylonitrile, acrylonitrile-α-methylstyrene copolymer, and polystyrene. , Styrene-divinylbenzene copolymer, polyvinyl acetate, polyethylene carbonate, polytetrafluoroethylene, etc., examples of cellulose derivatives such as methylcellulose, cellulose acetate, cellulose acetate propionate, 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. As examples of the inorganic compound, 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 can be preferably used. 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 of the coating film and the surface gloss, the particle size, shape, and particle size distribution can be changed as necessary during the preparation of the matting agent or by mixing a plurality of matting agents. preferable.

In the present invention, the matting degree of the backing layer is preferably such that the Beck smoothness is 250 seconds or less and 10 seconds or more.
More preferably, the time is 180 seconds or less and 50 seconds or more.

In the present invention, the matting agent is preferably contained in the outermost surface layer of the photographic material, a layer functioning as the outermost surface layer, or a layer close to the outer surface. It is preferable to be contained.

In the present invention, suitable binders for the backing layer are transparent or translucent, generally colorless, and include natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as: gelatin, acacia, poly (vinyl). Alcohol), hydroxyethylcellulose, cellulose acetate, cellulose acetate butyrate, poly (vinylpyrrolidone), 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 (ester) s, poly (urethane) s, phenoxy resin, poly (vinylidene chloride), poly (epoxide) s, poly (carbonate) s, poly (vinyl acetate), cellulose esters, polyamide)
There is kind. The binder may be coated from water or an organic solvent or emulsion.

In the present invention, the backing layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less, more preferably an antihalation layer having an optical density of 0.5 or more and 2 or less. . When an antihalation dye is used in the present invention, such a dye has a desired absorption in a desired wavelength range, has a sufficiently small absorption outside the desired wavelength range, and has a preferable absorbance spectrum shape of the backing layer. Any compound may be used as long as it is obtained. For example, JP-A-7-13295, U.S. Patent 5,380,635
The compound described in JP-A No. 2-68539, page 13, lower left column, line 1 to page 14, lower left column, line 9; JP-A-3-24539, page 14, lower left column, page 16, lower right column. Described compounds,
The present invention is not limited to this.

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.

The photothermographic material according to a preferred embodiment of the present invention may be developed by any method, but is usually developed by raising the temperature of the photothermographic material exposed imagewise. A preferred development temperature is 80 to 250 ° C,
More preferably, it is 100 to 140 ° C. The development time is preferably from 1 to 180 seconds, more preferably from 10 to 90 seconds.

The latent image can be formed on the photothermographic material of the present invention by any method, but a laser beam is preferred as an exposure light source. As the laser beam according to the present invention, a gas laser, a YAG laser, a dye laser, a semiconductor laser and the like are preferable. Further, a semiconductor laser and a second harmonic generation element can be used.

When the photothermographic material of the present invention contains no photosensitive silver halide, the photothermographic material of the present invention can form a latent image by heating. Heating can be done by direct heating using a thermal head, etc., or by indirectly heating a material that absorbs a specific wavelength and converting it to heat (dye, pigment, etc.). A method is also acceptable. The light source used at this time is preferably the laser beam described above. Furthermore, these can be combined. Further, when a latent image is formed by heating, a latent image may be formed by heating in a first stage, and an image may be formed in a second stage. It can be performed up to the formation.

[0180]

EXAMPLES Examples will be shown below to further illustrate specific embodiments of the present invention.

Example-1 The structure of the additive used in Example-1 is shown below.

[0182]

Embedded image

(Preparation of silver halide particles A) 7.5 g of inert gelatin and 10 mg of potassium bromide were dissolved in 900 ml of water, the pH was adjusted to 3.0 at a temperature of 35 ° C., and 370 ml of an aqueous solution containing 74 g of silver nitrate and bromide were added. An aqueous solution containing potassium and potassium iodide in a molar ratio of 94: 6 and containing K ₃ [IrCl ₆ ] was added over 10 minutes by the control double jet method while maintaining the pAg at 7.7. [IrCl ₆ ] ^3- was added at 3 × 10 ⁻⁷ mol per mol of silver. Then 4-hydroxy-6-methyl-
0.3 g of 1,3,3a, 7-tetrazaindene was added and the pH was adjusted to 5 with NaOH.
Adjust the average size to 0.06μm, projection area variation coefficient 8%,
Cubic silver iodobromide grains having a {100} face ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, and after desalting, 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and the pAg to 7.5.

(Preparation of Organic Acid Silver Emulsion A) Behenic acid 10.6
g, 300 ml of distilled water at 90 ° C. for 15 minutes, 31.1 ml of 1N-NaOH aqueous solution was added over 15 minutes with vigorous stirring, and the mixture was left as it was for 1 hour and then cooled to 30 ° C. Next, 7 ml of a 1N-phosphoric acid aqueous solution was added, and 0.13 g of N-bromosuccinimide was added while stirring more vigorously, and the silver halide particles A prepared in advance were adjusted to have a silver halide amount of 1.25 mmol. Was added. Furthermore, 25m of 1N-silver nitrate aqueous solution
was continuously added over 2 minutes, and stirring was continued for 90 minutes. After adding 37 g of a 1.2% by weight butyl acetate solution of polyvinyl acetate to this aqueous mixture to form flocs of the dispersion,
After removing the water and performing two more water washes and water removal,
20 g of a 2.5 wt% mixed solution of polyvinyl butyral (Denka Butyral # 3000-K, manufactured by Denki Kagaku Kogyo KK) and 1: 2 isopropyl alcohol were added with stirring, and the gelled organic acid thus obtained was added. 7.8 g of polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo Co., Ltd.) and 57 g of 2-butanone were added to the mixture of silver halide and dispersed with a homogenizer, and a silver behenate emulsion (mean minor axis 0.06 μm) , Needle-shaped particles having an average major axis of 1 µm and a variation coefficient of 30%).

(Preparation of Emulsion Layer Coating Solution A) The following chemicals were added to the above-obtained organic acid silver emulsion in the following amounts per mole of silver. At 25 ° C, (C-1) 1.0 g, sensitizing dye A 0.65 g,
2.1 g of (C-2), 14.2 g of (C-3), 580 g of 2-butanone, 220 g of dimethylformamide, and 32 g of methanol were added with stirring, and left for 3 hours. Then (C-4) 14.1 g, (C-5) 1
25 g, hydrazine derivative (Exemplified Compound 54a)
86 g, (C-6) 0.67 g, the compound of the general formula (1) and (C-1)
1) (Types and addition amounts (mol / mol A shown in Table 28)
g)), Megafax F-176P (fluorinated surfactant manufactured by Dainippon Ink and Chemicals, Inc.) 1.1 g, sumidur N3500
(Sumitomo Bayer Urethane Polyisocyanate) 3.7g
Was added with stirring.

(Preparation of Coating Solution for Emulsion Surface Protective Layer) CAB171-15S
(Cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.)
45 g, 2-butanone 1520 g and ethyl acetate 10 g, dimethylformamide 50 g, (C-7) 1.4 g, (C-8) 11.6 g, (C-9) 5.
4 g, (C-10) 4.0 g, compound of general formula (1) and (C-12)
(Types and addition amounts (mol / mol A shown in Table 28)
g)), Megafax F-176P0.43g, Sildex H31
(Doukai Chemical's spherical silica average size 3μm) 1.2g, su
A solution of 0.42 g of midur N3500 (polyisocyanate manufactured by Sumitomo Bayer Urethane) in 4.2 g of ethyl acetate was added and dissolved.

(Preparation of Support Having Back Surface) 6 g of polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo KK), Sildex H121 (average size of spherical silica 12 μm, manufactured by Dokai Chemical Co., Ltd.) 0.2 g, Sildex H51 (Tokai Chemical Co., Ltd., spherical silica average size 5 μm) 0.2 g, 0.1 g
Of Megafax F-176P was added to 64 g of 2-propanol with stirring and dissolved and mixed. In addition, 420mg
A mixed solution of (C-6) dissolved in 10 g of methanol and 20 g of acetone and a solution of 0.8 g of sumidur N3500 (polyisocyanate manufactured by Sumitomo Bayer Urethane) in 6 g of ethyl acetate were added to prepare a coating solution.

A coating solution for the back side was applied on a polyethylene terephthalate film having a moisture-proof undercoat containing vinylidene chloride on both sides so as to have an optical density of 780 nm of 0.7.
After the emulsion layer coating solution was coated on the support prepared as described above so that the silver content was 1.6 g / m ² , the emulsion surface protective layer coating solution was dried on the emulsion surface to a dry thickness of 1.8 μm. Was applied.

(Evaluation of photographic performance) The above sample was exposed to xenon flash light having an emission time of 10 ^-4 sec through an interference filter having a peak at 780 nm and a step wedge. Then, this exposed sample is heated using a heat drum.
Heat development was performed at 115 ° C., 117 ° C., and 120 ° C. for 25 seconds. The density of the obtained image was measured.

The performance evaluation was performed on the following items. Dmin (fogging); minimum density S1.5 (sensitivity); relative value of -log (reciprocal of exposure amount required to obtain density 1.5) ΔS1.5; sensitivity difference between development processing at 115 ° C and 120 ° C (Δlog
E) G0330 (gradation γ); G0330 = (3.0−0.3)) ÷ (S3.0-S0.
3) S3.0 = -log (reciprocal of the exposure required to obtain a density of 3.0) S0.3 = -log (reciprocal of the exposure required to obtain a density of 0.3) It is shown in Table 28.

[0191]

[Table 28]

(Results) In Comparative Sample No. 101, the fog was high, the gamma was low, and the sensitivity variation due to the development temperature change was very large. Further, in Comparative Sample Nos. 110 and 120, the fogging did not sufficiently fall and the sensitivity variation was large. On the other hand, in the samples of the present invention, the fogging is low and the sensitivity variation due to the temperature change is small.

Example 2 The hydrazine derivative of Example 1 was replaced with the aforementioned compound 54.
Example 1 except that r, 56a, 96-1, and 37p were replaced.
A sample was prepared in the same manner as described above, and its performance was evaluated. With the sample of the present invention, good results were obtained.

Example 3 (Preparation of silver halide particles B) After dissolving 22 g of phthalated gelatin and 30 mg of potassium bromide in 700 ml of water, adjusting the pH to 5.0 at a temperature of 40 ° C., and containing 18.6 g of silver nitrate Aqueous solution 159m
l and an aqueous solution containing potassium bromide were added over 10 minutes by the control double jet method while maintaining the pAg at 7.7.
An aqueous solution containing 8 × 10 ⁻⁶ mol / L of K ₃ [IrCl ₆ ] ^3- and 1 mol / L of potassium bromide was added over 30 minutes by the control double jet method while maintaining the pAg at 7.7.
Thereafter, the pH was adjusted to 5.9 and pAg 8.0.

The obtained particles had an average particle size of 0.07 μm.
m, coefficient of variation of projected area diameter 8%, (100) area ratio 86%
Was cubic particles.

The above silver halide grains B were heated to a temperature of 60 ° C., and 8.5 × 10 ⁻⁵ mol of sodium thiosulfate and 1.1 × 10 ⁻⁵ mol of 2,3,4,5, 6-pentafluorophenyldiphenylsulfine selenide, 2 × 10 ⁻⁶ mol of the following tellurium compound-1, 3.3 × 10 ⁻⁶ mol of chloroauric acid, 2.3 ×
10 ^-4 mol of thiocyanic acid was added and aged for 120 minutes. Thereafter, at a temperature of 50 ° C., 8 × 10 ^-4 mol of the following sensitizing dye-B was added with stirring, and 3.5 × 10 ^-2 mol of potassium iodide was further added, followed by stirring for 30 minutes. The mixture was rapidly cooled to ℃ to complete the preparation of silver halide grains.

[0197]

Embedded image

(Preparation of Organic Acid Silver Microcrystal Dispersion) Behenic Acid
40 g, stearic acid 7.3 g and distilled water 500 ml were mixed at 90 ° C. for 15 minutes, and 1N-NaOH aqueous solution 187 ml was added over 15 minutes with vigorous stirring, 1N-nitric acid aqueous solution 61 ml was added, and the temperature was lowered to 50 ° C. . Next, add 124 ml of 1N silver nitrate aqueous solution and leave
Stir for 30 minutes. Then, the solid content was filtered by suction filtration,
The solid content was washed with water until the conductivity of the filtrate reached 30 μS / cm. The solid content thus obtained was handled as a wet cake without drying, and 12 g of polyvinyl alcohol and 150 ml of water were added to a wet cake having a dry solid content of 34.8 g and mixed well to form a slurry. Prepare 840 g of zirconia beads having an average diameter of 0.5 mm, put them in a vessel together with the slurry, disperse them in a dispersing machine (1 / 4G-sand grinder mill: manufactured by IMEX Co., Ltd.) for 5 hours, and obtain a volume-weighted average of 1.5 μm. Of organic acid silver microcrystal dispersion was obtained. Particle size measurements are available from Malvern Instruments Ltd.
It was performed with MasterSaizerX manufactured by the company.

(Preparation of Material Solid Fine Particle Dispersion) Tetrachlorophthalic acid, 4-methylphthalic acid, 1,1-bis (2
-Hydroxy-3,5-dimethylphenyl) -3,5
Solid fine particle dispersions were prepared for 5-trimethylhexane, phthalazine, and tribromomethylphenol sulfone.

To tetrachlorophthalic acid, 0.81 g of hydroxypropylcellulose and 94.2 ml of water were added, stirred well, and left as a slurry for 10 hours. Thereafter, 100 ml of zirconia beads having an average diameter of 0.5 mm and a slurry were put together in a vessel and dispersed for 5 hours using a dispersing machine of the same type as that used for the preparation of the silver salt of organic acid microcrystals. Was obtained. As for the particle size of the solid fine particles, 70 wt% was 1.0 μm or less.

With respect to the other materials, the amount of the dispersant used and the dispersion time were appropriately changed in order to obtain a desired average particle size, and a solid fine particle dispersion was obtained.

(Preparation of Emulsion Layer Coating Solution) The following compositions were added to the previously prepared organic acid silver microcrystal dispersion to prepare emulsion coating solutions.

Organic acid silver microcrystal dispersion 0.95 mol Silver halide particles B 0.05 mol Binder: SBR latex (LACSTAR 3307B, manufactured by Dainippon Ink and Chemicals, Inc.) 430 g Material for development: tetrachlorophthalic acid 5 g 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane 98 g phthalazine 9.2 g tribromomethylphenylsulfone 12 g 4-methylphthalic acid 7 g hydrazine derivative (exemplified compound 54a) 1.5 g Compound of the general formula (1) of the present invention (kind and addition amount shown in Table 29; mol / mol Ag) The following (C-11) (addition amount shown in Table 29; mol / mol A)
g)

The average particle size of the dispersed particles of LACSTAR 3307B, which is a latex of a styrene-butadiene copolymer, is about 0.1 to 0.15 μm.
The equilibrium water content under the condition of 60 ° C. and 60% RH was 0.6% by weight.

[0205]

Embedded image

(Preparation of Emulsion Protective Layer Coating Solution) The following compositions were added to inert gelatin to prepare an emulsion protective layer coating solution.

Inert gelatin 10 g Surfactant A (described below) 0.26 g Surfactant B (described below) 0.09 g Fine silica particles (average particle size 2.5 μm) 0.9 g 1,2- (bisvinylsulfone acetamide) ethane 0 0.3 g water 64 g Compound of the general formula (1) of the present invention (type shown in Table 29,
(Amount: mol / mol Ag) The following (C-12) (types and addition amounts shown in Table 29; mol / mol Ag)
Mol Ag)

[0208]

Embedded image

(Preparation of Coloring Agent Dispersion A) Ethyl acetate 35
2.5 g each of the following compounds 1 and 2,
7.5 g was added and dissolved by stirring. To this solution was added 50 g of a 10% by weight solution of polyvinyl alcohol previously dissolved, and the mixture was dispersed with a homogenizer for 5 minutes. Thereafter, ethyl acetate was removed by removing the solvent, and then diluted with water to prepare a color former dispersion.

[0210]

Embedded image

(Preparation of Back Surface Coating Solution) The following compositions were added to polyvinyl alcohol to prepare a back surface coating solution.

Polyvinyl alcohol 30 g Coloring agent dispersion A 50 g Additive-A (described below) 20 g Water 250 g Sildex H121 (Tokai Chemical Co., Ltd., spherical silica average size 12 μm) 1.8 g

[0213]

Embedded image

(Preparation of photosensitive material) The emulsion layer coating solution prepared as described above was coated on a polyethylene terephthalate support at a silver concentration of 1.6 g / m ² . The emulsion protective layer coating solution was coated thereon so that the coating amount of gelatin was 1.8 g / m ² . After drying, a coating solution for the back surface was applied on the surface opposite to the emulsion layer so that the optical density at 660 nm was 0.7, thereby preparing a sample.

(Evaluation of Photographic Performance) The above sample was exposed to xenon flash light having an emission time of 10 ⁻⁴ sec through a step wedge through an interference filter having a peak at 656 nm, and evaluated in the same manner as in Example 1. The results are shown in Table 29 together with the thermal development temperature conditions.

[0216]

[Table 29]

(Results) It can be seen that the photographic processing performance of the sample of the present invention can be obtained in the same manner as in Example-1.

Example 4 The hydrazine derivative of Example 3 was replaced with the aforementioned Compound 54.
Example 3 except that r, 56a, 96-1, and 37p were replaced.
A sample was prepared in the same manner as described above, and its performance was evaluated. With the sample of the present invention, good results were obtained.

[0219]

From the above results, according to the present invention, the present invention is suitable for a printing photographic material having a super-high contrast performance, a small fluctuation in photographic performance with respect to fluctuations in development processing temperature and the like, and a stable image can be obtained. A heat-developable photographic material can be provided.

Claims (2)

[Claims] (1) a reducible silver salt, (b) a reducing agent,
A heat-developable photographic material comprising (c) a super-high contrast agent, (d) a binder, and (e) at least one compound represented by the general formula (1). Embedded image [In the general formula (1), Z ₁ represents an aliphatic hydrocarbon group or an aryl group, and Z ₂ represents an aryl group. ] 2. The photothermographic material according to claim 1, which contains a photosensitive silver halide as a photocatalyst.