JP2002365758A - Heat developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developable photosensitive material capable of forming an image by short-time processing and having an excellent silver tone of an image and excellent aging stability of an image after processing. SOLUTION: In the heat developable photosensitive material having at least one photosensitive silver halide, a reducer, etc., on one face of a substrate, the reducer is a compound of formula (R1) and at least one compound of the formula Q<1> -NHNHCONH-R<1> (A) is contained. In the formula (R1), R<11> and R<11> ' are each a 4-20C tertiary alkyl; R<12> and R<12> ' are each H, phenyl or the like; and R<13> is H or a 1-20C alkyl. In the formula (A), Q<1> is aryl or a heterocyclic group and R<1> is alkyl or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material, and more particularly, to a photothermographic material capable of forming an image in a short time, and having excellent silver tone of the image and excellent stability over time of the processed image. It relates to a photosensitive material.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand in the medical field to reduce the amount of waste liquid from the viewpoint of environmental protection and space saving.
Therefore, a photosensitive photosensitive material for medical diagnostics and photographic technology can be efficiently exposed by a laser imagesetter or a laser imager, and can form a sharp black image having high resolution and sharpness. There is a need for technology for developed photographic materials. These photothermographic materials can eliminate the use of solution processing chemicals and provide a simpler and more environmentally friendly thermal development system to customers.

[0003] Although there is a similar demand in the field of general image forming materials, medical images require high-quality images with excellent sharpness and granularity due to the need for fine depiction. From the viewpoint, there is a feature that a cool tone image is preferred. At present, various hard copy systems using pigments and dyes, such as ink jet printers and electrophotographs, are distributed as general image forming systems, but there is a problem that there is no satisfactory medical image output system.

On the other hand, a thermal image forming system using an organic silver salt is disclosed in, for example, US Pat. Nos. 3,152,904 and 345.
No. 7075 and B.I. Shelly
"Thermal Treated Silver System (Ther
Mally Processed Silver Sy
stems) "(Imaging Processes and Materials)
s and Materials) Neblette
Eighth Edition, Sturge, V.S. Walworth, A.M. Shepp
Compilation, page 2, 1996).

A photothermographic material generally has a catalytically active amount of a photocatalyst (eg, silver halide), a reducing agent, a reducible silver salt (eg, a non-photosensitive organic silver salt), and controls the color tone of silver if necessary. The photosensitive layer has a color tone agent dispersed in a binder matrix. After the image exposure, the photothermographic material is heated to a high temperature (for example, 80 ° C. or higher), and is subjected to a redox reaction between a silver halide or a reducible silver salt (which functions as an oxidizing agent) and a reducing agent. To form a silver image. The oxidation-reduction reaction is promoted by the catalytic action of the latent image of silver halide generated by exposure. Therefore, a black silver image is formed in the exposed area. US Patent 291037
No. 7, the Japanese Patent Publication No. 43-4924, and many other documents. As a medical image forming system using a photothermographic material, Fuji Medical Dry Imager FM-DPL has been released.

The above photothermographic material has environmental advantages,
It is excellent in terms of easy handling, space saving, etc.
Although well received in the market, further improvements are desired. In particular, further improvements are desired in terms of reduction in processing time, preservation of unused photographic materials, and stability of images after processing. Among them, particularly, it has been strongly desired that the silver color tone be a natural color tone close to the conventional wet processing system and that the color tone does not change with time. That is, the heat-developable light-sensitive material is such that the elements necessary for image formation are left as it is in the light-sensitive material after processing. There was a problem that it was inferior to the above.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, an object of the present invention is to provide a photothermographic material which can form an image in a short time, and has excellent silver tone of the image and excellent stability with time of the processed image.

[0008]

Means for solving the above problems are as follows. <1> A photothermographic material comprising at least one photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent for silver ions, and a binder on one surface of a support. A photothermographic material characterized in that the agent is a compound represented by the following general formula (R1) and contains at least one compound having no high contrast function represented by the following general formula (A). is there.

[0009]

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In the general formula (R1), R ¹¹ and R
^{11 ′} each independently represents a tertiary alkyl group having 4 to 20 carbon atoms. R ¹² and R ^{12 ′} each independently represent a hydrogen atom, a phenyl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylthio group or an arylthio group. R
¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. General formula (A) Q ¹ -NHNHCONH-R ^{1 In the} general formula (A), Q ¹ represents an aryl group or a heterocyclic group. R ¹ represents an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group or a heterocyclic group.

<2> The compound represented by the general formula (A), which has no contrast-increasing effect, wherein Q ¹ is an aryl group substituted with an electron-withdrawing group or a substituted or unsubstituted heterocyclic group. A photothermographic material according to <1>.

<3> The above <2>, wherein the substituted or unsubstituted heterocyclic group is a monocyclic or condensed-ring heterocyclic group.
The photothermographic material according to item 1.

<4> The above <1> to <3> containing at least one compound represented by the following general formula (B):
> The photothermographic material according to any one of <1> to <3>.

[0014]

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In the general formula (B), R ¹ represents a tertiary alkyl group. R ² represents an alkyl group, an alkoxy group, or a halogen atom. R ³ represents a hydrogen atom, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group, or an amino group.

<5> The photothermographic material according to any one of <1> to <4>, containing a compound represented by the following general formula (D).

[0017]

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In the general formula (D), R ²¹ , R ²² ,
And R ²³ each independently represent a substituted or unsubstituted alkyl group, aryl group, alkoxy group, aryloxy group, amino group, or heterocyclic group. When R ²¹ , R ²² , and R ²³ have a substituent, the substituent is a halogen atom, an alkyl group, an aryl group, an alkoxy group, an amino group, an acyl group, an acylamino group, an alkylthio group, an arylthio group, a sulfonamide group. , An acyloxy group, an oxycarbonyl group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, or a phosphoryl group.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The photothermographic material of the present invention will be described below in detail. (Description of compounds contained in photothermographic material of the present invention)
The compound contained in the photothermographic material of the invention will be described in detail.

<Reducing Agent Represented by General Formula (R1)> The photothermographic material of the present invention contains a reducing agent represented by the following general formula (R1).

[0021]

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In the general formula (R1), R ¹¹ and R
^{11 ′} each independently represents a tertiary alkyl group having 4 to 20 carbon atoms. R ¹² and R ^{12 ′} each independently represent a hydrogen atom, a phenyl group, a hydroxy group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylthio group, or an arylthio group. R ¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

The general formula (R1) will be described in detail. R ¹¹ and R ^{11 ′} are each 3 to 4 carbon atoms.
Secondary alkyl groups are preferred. Specifically, tert-butyl group, tert-amyl group, 1,1, -dimethylpropyl group, 1,1-dimethylbutyl group, 1,1-dimethylhexyl group, 1,1,3,3-tetramethyl Butyl group,
1,1-dimethyldecyl group, 1-methylcyclohexyl group, tert-octyl group, 1-methylcyclopropyl group and the like are preferable, and tert-butyl group, tert-amyl group, tert-octyl group and 1-methylcyclohexyl group are preferable. More preferred is a tert-butyl group.

When R ¹² and R ^{12 ′} are a phenyl group, an aryloxy group or an arylthio group, these groups may have a substituent. The substituent may be any group that can be substituted on a benzene ring, but may be an alkyl group, an aryl group, a heterocyclic group, a halogen atom, an alkoxy group, a hydroxy group, an aryloxy group, an alkylthio group, an arylthio group, an amino group, Examples include an acyl group, an acyloxy group, an acylamino group, an alkoxycarbonyl group, a carbamoyl group, a sulfonyl group, a sulfonamide group, a sulfonyloxy group, a sulfamoyl group, a sulfoxide group, a ureido group, and a urethane group. R ¹² and R
^{When 12 ′} is an alkoxy group or an alkylthio group,
These groups may further have a substituent, and examples of the substituent include an alkoxy group, an alkoxycarbonyl group, an acyloxy group, a sulfonyl group, a carbonyl group, an alkylthio group, an aryloxy group, an arylthio group, and a sulfone. Examples include an amide group and an acylamino group. R ¹² and R ^{12 ′} are more preferably a hydrogen atom, a methoxy group, or a benzyloxy group.

R ¹³ is preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group,
A 4-trimethylpentyl group is preferred. Particularly preferred as R ¹³ is a hydrogen atom, a methyl group, an ethyl group, a propyl group, or an isopropyl group.

Hereinafter, specific examples of the reducing agent represented by the general formula (R1) of the present invention are shown, but the present invention is not limited thereto.

[0027]

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[0028]

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[0029]

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The addition amount of the reducing agent represented by general formula (R1), it is preferably 0.01~5.0g / m ^2, is 0.1 to 3.0 g / m ² More preferred. 5 to 1 mol of silver on the surface having the image forming layer
It is preferably contained at 50 mol%, and 10 to 40 mol%
More preferably, it is included. In addition, the general formula (R
The reducing agent represented by 1) is preferably contained in the image forming layer.

The reducing agent represented by the general formula (R1) is
Solution form, emulsified dispersion form, solid fine particle dispersion form, etc.
The coating solution may be contained by any method and may be contained in the photosensitive material. Well-known emulsification dispersion methods include oils such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone. A method for producing the same is given. Further, as a solid fine particle dispersion method, a powder of a reducing agent is dispersed in a suitable solvent such as water by a ball mill, a colloid mill, a vibration ball mill, a sand mill, a jet mill, a roller mill or ultrasonic waves to produce a solid dispersion. Method. In this case, a protective colloid (for example, polyvinyl alcohol) and a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. Good. The aqueous dispersion can contain a preservative (eg, benzoisothiazolinone sodium salt). The general formula (R
The reducing agent represented by 1) is preferably used in a solid dispersion method.

<Compound represented by the general formula (A), compound having no contrast-increasing effect> The photothermographic material of the present invention contains a compound represented by the following general formula (A), without a contrast-increasing effect. General formula (A) Q ¹ -NHNHCONH-R ^{1 In the} general formula (A), Q ¹ represents an aryl group or a heterocyclic group. R ¹ represents an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group or a heterocyclic group.

It is preferable that Q ¹ is an aryl group having 6 to 40 carbon atoms or a heterocyclic group having 2 to 40 carbon atoms. The aryl group represented by Q ^1, a phenyl group, a naphthyl group are preferred, and these groups may have a substituent. The substituent may be any group that can be substituted on a benzene ring, and examples thereof include a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxy group, an alkoxy group, an aryloxy group, an acyloxy group, and an alkylthio group. Arylthio group, amino group, acylamino group, sulfonamide group, ureido group, urethane group, acyl group, alkoxycarbonyl group, carbamoyl group, sulfamoyl group, sulfonyl group, sulfoxide group, cyano group, nitro group, sulfo group, or carboxy And the like. When Q ¹ is an aryl group, the aryl group is preferably substituted with an electron-withdrawing group, and at least one of the substituents is a halogen atom, a heterocyclic group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, It is preferably a sulfoyl group, a sulfonyl group, a sulfoxide group, a cyano group, a nitro group, a fluoroalkyl group such as a trifluoromethyl group, a fluoroaryl group such as a pentafluorophenyl group, or an electron-withdrawing group equal to or more than these. . Among them, a strong electron-withdrawing group such as an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, a cyano group, and a trifluoromethyl group is preferable, and an alkoxycarbonyl group, a sulfonyl group, a cyano group, and a trifluoromethyl group are particularly preferable. . When Q ¹ is an aryl group, the number of substituents of the aryl group is in the range of 0 to 5, but at least one is preferably the above-mentioned strong electron-withdrawing group, and more preferably the above-mentioned electron-withdrawing group. More preferably.

When Q ¹ is a heterocyclic group, preferred examples include a pyridine ring, a pyrazine ring, a pyrimidine ring,
Pyridazine ring, 1,2,4-triazine ring, 1,3,5
-Triazine ring, pyrrole ring, imidazole ring, pyrazole ring, 1,2,3-triazole ring, 1,2,4-triazole ring, tetrazole ring, 1,3,4-thiadiazole ring, 1,2,4-thiadiazole Ring, 1,2,5
-Thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,4-oxadiazole ring, 1,2,5-oxadiazole ring, thiazole ring, oxazole ring, isothiazole ring, isoxazole ring Or a thiophene ring, and a condensed ring in which these rings are condensed with each other is also preferable. Further, the heterocyclic ring may have a substituent, and when the heterocyclic ring has two or more substituents, those substituents may be the same or different. Examples of the substituent include a halogen atom, an alkyl group, an aryl group,
A carbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a carbamoyl group, a sulfamoyl group, a cyano group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group,
An aryloxycarbonyl group, and an acyl group. When these substituents are substitutable groups, they may further have a substituent. Examples of the substituent include a halogen atom, an alkyl group, an aryl group, a carbonamide group,
Alkylsulfonamide, arylsulfonamide, alkoxy, aryloxy, alkylthio, arylthio, acyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, cyano, sulfamoyl, alkylsulfonyl, arylsulfonyl And acyloxy groups.

The group represented by R ¹ has 1 carbon atom.
An alkyl group of -40, an alkenyl group of 2-40 carbon atoms,
An alkynyl group, a cycloalkyl group having 3 to 40 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a heterocyclic group having 2 to 40 carbon atoms is preferable. These groups may further have a substituent.

When R ¹ is an alkyl group having 1 to 40 carbon atoms, a primary alkyl group having 4 to 30 carbon atoms,
A secondary alkyl group having from 30 to 30 carbon atoms or a tertiary alkyl group having from 4 to 30 carbon atoms is preferable, and a primary alkyl group having from 6 to 18 carbon atoms, a secondary alkyl group having from 3 to 18 carbon atoms, or from 4 to 30 carbon atoms.
18 tertiary alkyl groups are more preferred. Among them, 2
A tertiary or tertiary alkyl group is preferred, and a tertiary alkyl group is more preferred. Specific examples of the alkyl group include a methyl group, a propyl group, an n-butyl group, an n-hexyl group,
-Octyl group, n-dodecyl group, n-hexadecyl group,
Neopentyl group, 2-ethylhexyl group, 2-octyloctyl group, isopropyl group, 1-hexylhexyl group, t-butyl group, 1,1,3,3-tetramethyloctyl group, 1,1-dimethylhexyl group, Examples thereof include a 1,1-dimethyldecyl group, a benzyl group, a phenethyl group, a phenoxyethyl group, and a 2,4-di-t-amylphenoxypropyl group.

When R ¹ is an alkenyl group, an alkenyl group having 2 to 20 carbon atoms is preferable, and examples thereof include a vinyl group, an allyl group and an oleyl group.

When R ¹ is a cycloalkyl group,
A cycloalkyl group having 3 to 20 carbon atoms is preferable, for example, a cyclopropyl group, a 1-ethylcyclopropyl group,
Examples thereof include a cyclopentyl group, a cyclohexyl group, a 1-methylcyclohexyl group, a 2,2,2-bicyclooctyl group, a norbornyl group, and an adamantyl group.

When R ¹ is an aryl group, it is preferably a phenyl group, a naphthyl group or the like, and these groups may have a substituent. The substituent may be any group that can be substituted on a benzene ring, and examples thereof include a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxy group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylthio group, and an arylthio group. , Amino group, acylamino group,
Examples thereof include a sulfonamide group, a ureido group, a urethane group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, a sulfoxide group, a cyano group, a nitro group, a sulfo group, and a carboxy group.

The heterocyclic group represented by R ¹ includes a pyridine ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring,
1,2,4-triazine ring, 1,3,5-triazine ring, pyrrole ring, imidazole ring, pyrazole ring,
2,3-triazole ring, 1,2,4-triazole ring, tetrazole ring, 1,3,4-thiadiazole ring,
1,2,4-thiadiazole ring, 1,2,5-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,2
Preferable examples include a 4-oxadiazole ring, a 1,2,5-oxadiazole ring, a thiazole ring, an oxazole ring, an isothiazole ring, an isoxazole ring, and a thiophene ring. These rings may be single rings or condensed rings fused together. The heterocyclic group may have a substituent, and when it has two or more substituents, those substituents may be the same or different. Examples of the substituent include a halogen atom, an alkyl group, an aryl group, a carbonamide group, an alkylsulfonamide group, an arylsulfonamide group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a carbamoyl group, a sulfamoyl group, Examples include a cyano group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, and an acyl group. When the substituent is a substitutable group, the substituent may further have a substituent. Examples of the preferable substituent include a halogen atom, an alkyl group, an aryl group, a carbonamido group, an alkylsulfonamido group, and an arylsulfone. Amide group, alkoxy group, aryloxy group, alkylthio group, arylthio group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, cyano group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, and acyloxy group Can be

Among the compounds represented by the general formula (A), those wherein Q ¹ is a 5- or 6-membered unsaturated ring are preferable, and a benzene ring, a pyrimidine ring, a 1,2,3-triazole ring, 1,2,4-triazole ring, tetrazole ring, 1,3,4-thiadiazole ring, 1,2,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,
A 2,4-oxadiazole ring, a thiazole ring, an oxazole ring, an isothiazole ring, an isoxazole ring, or a ring in which these rings are condensed with a benzene ring or an unsaturated heterocycle are more preferable, and a quinazoline ring is particularly preferable. preferable.

The above-mentioned Q ¹ preferably has at least one electron-withdrawing substituent, and is preferably a fluoroalkyl group (for example, trifluoromethyl group, pentafluoroethyl group, , 1-difluoroethyl group, difluoromethyl group, fluoromethyl group, heptafluoropropyl group, pentafluorophenyl group), cyano group, halogen atom (fluoro, chloro,
Bromo, iodo), an acyl group, an alkoxycarbonyl group, a carbamoyl group, an alkylsulfonyl group, and an arylsulfonyl group. A particularly preferred substituent is a trifluoromethyl group.

Hereinafter, specific examples of the compound represented by formula (A) are shown, but the compounds used in the present invention are not limited to these specific examples.

[0044]

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[0045]

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[0046]

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[0047]

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[0048]

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[0049]

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[0050]

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[0051]

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[0052]

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The amount of the compound represented by the general formula (A) is preferably 0.1 to 100 mol%, more preferably 0.5 to 10 mol%, based on the reducing agent. 1-5 mol% is more preferred. Further, the compound represented by the general formula (A) is preferably contained in the image forming layer.

The compound represented by formula (A) may be incorporated in the coating solution by any method such as a solution form, an emulsified dispersion form, and a solid fine particle dispersion form, and may be contained in the light-sensitive material. Well-known emulsification dispersion methods include oils such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone. A method for producing the same is given.

As a method for dispersing the solid fine particles, a powder of the compound represented by the general formula (A) is dissolved in a suitable solvent such as water in a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill or a super mill. A method of dispersing by a sound wave to produce a solid dispersion is exemplified.
In this case, a protective colloid (for example, polyvinyl alcohol) and a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. Good. The aqueous dispersion can contain a preservative (eg, benzoisothiazolinone sodium salt). The compound represented by the general formula (A) is desirably used in a solid dispersion method from the viewpoint of storage stability of the photosensitive material and stability of coating.

<Compound Represented by General Formula (B)> The photothermographic material of the present invention contains at least one compound represented by the following general formula (B).

[0057]

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In the general formula (B), R ¹ represents a tertiary alkyl group. R ² represents an alkyl group, an alkoxy group, or a halogen atom. R ³ represents a hydrogen atom, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group, or an amino group. R ¹ has 4 carbon atoms.
And a tertiary alkyl group having a carbon number of 4 to 12 is preferable.
Is more preferable. Specifically, ter
t-butyl group, 1,1, -dimethylpropyl group, 1,1
-Dimethylbutyl group, 1,1-dimethylhexyl group,
1,1,3,3-tetramethylbutyl group, 1,1-dimethyldecyl group, 1-methylcyclohexyl group, 1-methylcyclopropyl group and the like are preferable, and tert-butyl group, tert-amyl group, tert-octyl Group, 1-
A methylcyclohexyl group is more preferred, and a tert-butyl group is most preferred.

R ² is preferably an alkyl group having 1 to 20 carbon atoms, preferably a secondary or tertiary alkyl group having 3 to 12 carbon atoms, and more preferably a tertiary alkyl group having 4 to 8 carbon atoms. . Specifically, a tert-butyl group, t
An ert-amyl group, a tert-octyl group and a 1-methylcyclohexyl group are preferred, and a tert-butyl group is particularly preferred. The preferred substitution position of R ² is the ortho position of the phenolic hydroxyl group.

R ³ is a hydrogen atom, a carbon number of 6 to
An aryl group having 30 carbon atoms, a hydroxy group, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, or an amino group having 2 to 30 carbon atoms is preferable. Among them, a hydrogen atom, a hydroxy group, an alkoxy group, or an aryl group is more preferred, and a hydrogen atom or an aryl group is still more preferred. In the case of the aryl group represented by R ^2, the aryl group may have a substituent. Examples of the substituent include a halogen atom, an alkyl group, a hydroxy group, an alkoxy group, an acyl group, an acylamino group, a sulfonamide group, a sulfonyl group, a sulfamoyl group, a carbamoyl group, and a ureido group.A preferred substituent is alkyl. And hydroxy groups. Particularly preferred as R ³ is 4-hydroxy-3,5-di -tert- butylphenyl group.

Hereinafter, specific examples of the compound represented by the formula (B) will be shown, but the present invention is not limited thereto.

[0062]

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[0063]

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The amount of the compound represented by formula (B) is preferably from 0.1 to 100 mol%, more preferably from 0.5 to 10 mol%, based on the reducing agent. , 1 to 5 mol% is more preferred. Further, the compound represented by the general formula (B) is preferably contained in the image forming layer.

The compound represented by the general formula (B) may be incorporated in the coating solution by any method such as a solution form, an emulsified dispersion form and a solid fine particle dispersion form, and may be contained in the light-sensitive material. Well-known emulsification dispersion methods include oils such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone. A method for producing the same is given.

As a method for dispersing the solid fine particles, a powder of the compound represented by the general formula (B) is dissolved in a suitable solvent such as water in a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill or a super mill. A method of dispersing by a sound wave to produce a solid dispersion is exemplified.
In this case, a protective colloid (for example, polyvinyl alcohol) and a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. Good. The aqueous dispersion can contain a preservative (eg, benzoisothiazolinone sodium salt). The compound represented by the general formula (B) is desirably used in a solid dispersion method from the viewpoint of the storage stability of the photosensitive material and the stability of coating.

<Reducing Agent that can be Used in Combination with the Reducing Agent of the Present Invention> The photothermographic material of the present invention includes, in addition to the reducing agent represented by formula (R1), a reducing agent for non-photosensitive organic silver salts. Agents can be used in combination. The reducing agent for the non-photosensitive organic silver salt can be any substance (preferably an organic substance) that reduces silver ions to metallic silver. Such reducing agents are described in paragraphs 0043 to 0045 of JP-A-11-65021.
And page 7, line 34 to page 18, line 12 of European Patent Publication No. 0803764A1.

As the reducing agent that can be used in combination with the reducing agent in the present invention, a hindered phenol reducing agent and a bisphenol reducing agent are preferable, and a compound represented by the following formula (R2) is more preferable.

[0069]

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In the general formula (R2), R ¹¹ and R
^{11 ′} each independently represents an alkyl group having 1 to 20 carbon atoms. R ¹² and R ^{12 ′} each independently represent a hydrogen atom or a substituent that can be substituted on a benzene ring. L is a -S- group or-
Represents a CHR ¹³ — group. R ¹³ is a hydrogen atom or carbon number 1-2
Represents an alkyl group of 0. X ¹ and X ^{1 ′} each independently represent a hydrogen atom or a group that can be substituted on a benzene ring. However,
R ¹¹ and R ^{11 ′} represent a tertiary alkyl group, and R ¹² and R ^{12 ′}
Each independently represents a methyl group, a benzyl group, an alkoxymethyl group, an aryloxymethyl group, an acyloxymethyl group, an alkylthiomethyl group, or an arylthiomethyl group, and R ¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. Excluding the case where

Hereinafter, the general formula (R2) will be described in detail. R ¹¹ and R ^{11 ′} each independently represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Although the substituent of the alkyl group is not particularly limited, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acylamino group, a sulfonamide group, a sulfonyl group, a phosphoryl group,
Preferred are an acyl group, a carbamoyl group, an ester group, a halogen atom and the like.

R ¹² and R ^{12 ′} each independently represent a hydrogen atom or a substituent that can be substituted on a benzene ring. The X
¹ and X ^{1 ′} each independently represent a hydrogen atom or a group that can be substituted on a benzene ring. As the group that can be substituted on the benzene ring, an alkyl group, an aryl group, a halogen atom, an alkoxy group, and an acylamino group are preferable.

The above L represents a —S— group or a —CHR ¹³ — group. R ¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. The alkyl group may have a substituent. When R ¹³ represents an unsubstituted alkyl group, specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, an undecyl group, an isopropyl group,
Examples thereof include an ethylpentyl group and a 2,4,4-trimethylpentyl group. Examples of the substituent of the alkyl group, the same as the substituent of R ^11, a halogen atom, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an acylamino group, a sulfonamido group, a sulfonyl group, a phosphoryl group, an oxy A carbonyl group, a carbamoyl group, a sulfamoyl group and the like are preferred.

R ¹¹ and R ^{11 ′ each} have 3 to 3 carbon atoms.
Preferred are 15 secondary or tertiary alkyl groups. Specifically, isopropyl, isobutyl, t-butyl, t
-Amyl group, t-octyl group, cyclohexyl group, cyclopentyl group, 1-methylcyclohexyl group, 1-methylcyclopropyl group and the like. R ¹¹ and R ^{11 ′}
Is more preferably a tertiary alkyl group having 4 to 12 carbon atoms, and among them, a t-butyl group, a t-amyl group, and a 1-methylcyclohexyl group are still more preferable, and a t-butyl group is most preferable.

R ¹² and R ^{12 ′ each} have 1 to 1 carbon atoms.
Twenty alkyl groups are preferred. Specifically, a methyl group,
Ethyl group, propyl group, butyl group, isopropyl group, t
-Butyl group, t-amyl group, cyclohexyl group, 1-methylcyclohexyl group, benzyl group, methoxymethyl group, methoxyethyl group and the like are preferable, and methyl group, ethyl group, propyl group, isopropyl group, and t-butyl group are more preferable. preferable. X ¹ and X ^{1 ′} are preferably a hydrogen atom,
It is a halogen atom or an alkyl group, more preferably a hydrogen atom.

The above L is preferably a —CHR ¹³ — group. R ¹³ is preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group,
A 4-trimethylpentyl group is preferred. Particularly preferred as R ¹³ is a hydrogen atom, a methyl group, a propyl group or an isopropyl group.

The above R¹¹And R^{11 '}Is a tertiary alkyl group
If R¹²And R^{12 '}Is an alkyl group having 2 to 5 carbon atoms
Are preferred, and an ethyl group and a propyl group are more preferred.
A tyl group is most preferred. The R¹³Is primary with 1-8 carbon atoms
Or, when it is a secondary alkyl group, R¹²And R ^{12 '}Hame
A tyl group is preferred. The R¹³A primary having 1 to 8 carbon atoms or
Secondary alkyl groups include methyl, ethyl, and
Pill groups and isopropyl groups are more preferred, and methyl groups and
A tyl group and a propyl group are more preferred. The R¹¹And R
^{11 '}, R¹²And R^{12 '}Are all methyl groups
Is R¹³Is preferably a secondary alkyl group. This
If R¹³Isopropyl as the secondary alkyl group
Group, isobutyl group, 1-ethylpentyl group is preferred,
An isopropyl group is more preferred.

The following are specific examples of the reducing agent that can be used in combination with the reducing agent of the present invention, including the compound represented by the general formula (R2), but the present invention is not limited thereto.

[0079]

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[0080]

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[0081]

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[0082] The addition amount of the reducing agent represented by the general formula (R2) of the present invention is preferably from 0.01~5.0g / m ^2, is 0.1 to 3.0 g / m ² Is more preferable. 5 to 1 mol of silver on the surface having the image forming layer
It is preferably contained in an amount of from 50 to 50 mol%, more preferably from 10 to 40 mol%. The reducing agent is preferably contained in the image forming layer.

The reducing agent may be contained in the coating solution by any method such as a solution form, an emulsified dispersion form and a solid fine particle dispersion form, and may be contained in the light-sensitive material. Well-known emulsification dispersion methods include oils such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone. A method for producing the same is given.

In the solid fine particle dispersion method, a powder of a reducing agent is dispersed in a suitable solvent such as water by a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill or ultrasonic waves to obtain a solid dispersion. Is produced. In this case, a protective colloid (for example, polyvinyl alcohol) and a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. Good. The aqueous dispersion can contain a preservative (eg, benzoisothiazolinone sodium salt).

<Description of Hydrogen Bonding Compound> When the reducing agent in the present invention has an aromatic hydroxyl group (—OH),
In particular, in the case of the above-mentioned bisphenols, it is preferable to use a non-reducing compound having a group capable of forming a hydrogen bond with these groups. Examples of the group that forms a hydrogen bond with the hydroxyl group or the amino group include a phosphoryl group, a sulfoxide group, a sulfonyl group, a carbonyl group, an amide group, an ester group, a urethane group, a ureido group, a tertiary amino group, and a nitrogen-containing aromatic group. Is mentioned. Among them, preferred are a phosphoryl group, a sulfoxide group, an amide group (provided that they have no> NH group and are blocked like> N-Ra (Ra is a substituent other than H)), and a urethane group. (However, it has no> NH group and is blocked like> N-Ra (Ra is a substituent other than H)), and a ureido group (however, it has no> NH group, and> And N-Ra (Ra is a substituent other than H). In the present invention, a particularly preferred hydrogen bonding compound is a compound represented by the following formula (D).

[0086]

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In the general formula (D), R ²¹ , R ²² ,
And R ²³ each independently represent an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group, or a heterocyclic group, and these groups may be unsubstituted or have a substituent .

When R ²¹ , R ²² and R ²³ have a substituent, examples of the substituent include a halogen atom, an alkyl group, an aryl group, an alkoxy group, an amino group, an acyl group, an acylamino group, an alkylthio group and an arylthio group. , A sulfonamide group, an acyloxy group, an oxycarbonyl group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, a phosphoryl group, and the like. As the substituent, an alkyl group or an aryl group is preferable, and among them, a methyl group, an ethyl group, an isopropyl group, a t-butyl group, a t-octyl group,
A phenyl group, a 4-alkoxyphenyl group and a 4-acyloxyphenyl group are more preferred.

The alkyl group represented by R ²¹ , R ²² and R ²³ includes a methyl group, an ethyl group, a butyl group, an octyl group, a dodecyl group, an isopropyl group, a t-butyl group and a t-butyl group.
-Amyl group, t-octyl group, cyclohexyl group, 1-
Methylcyclohexyl group, benzyl group, phenethyl group,
R ²¹ and R ²¹ described above which include a 2-phenoxypropyl group and the like.
Examples of the aryl group represented by ²² and R ²³ include a phenyl group, a cresyl group, a xylyl group, a naphthyl group, a 4-t-butylphenyl group, a 4-t-octylphenyl group, a 4-anisidyl group, and a 3,5-dichlorophenyl group And the like.

The alkoxy group for R ²¹ , R ²² and R ²³ includes methoxy, ethoxy, butoxy, octyloxy, 2-ethylhexyloxy,
Examples thereof include a 3,5,5-trimethylhexyloxy group, a dodecyloxy group, a cyclohexyloxy group, a 4-methylcyclohexyloxy group, and a benzyloxy group. Examples of the aryloxy group include a phenoxy group, a cresyloxy group, an isopropylphenoxy group, a 4-t-butylphenoxy group, a naphthoxy group, a biphenyloxy group, and the like.

The amino groups in R ²¹ , R ²² and R ²³ include dimethylamino, diethylamino, dibutylamino, dioctylamino, N-methyl-N
-Hexylamino group, dicyclohexylamino group, diphenylamino group, N-methyl-N-phenylamino group and the like.

As R ²¹ , R ²² and R ²³ , an alkyl group, an aryl group, an alkoxy group and an aryloxy group are preferred. In terms of the effect of the present invention, R ²¹ , R ²² , and R
It is preferable that at least one of ²³ is an alkyl group or an aryl group, and it is more preferable that at least two of them are an alkyl group or an aryl group. Further, it is preferable that R ²¹ to R ²³ be the same group in that they can be obtained at low cost.

Hereinafter, specific examples of the hydrogen bonding compound including the compound represented by the general formula (D) will be shown.
The present invention is not limited to these.

[0094]

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[0095]

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Specific examples of the hydrogen bonding compound are described in Japanese Patent Application Nos. 2000-192191 and 2000-19
No. 4811. The compound represented by the general formula (D) may be in the form of a solution, like the reducing agent,
It can be incorporated in a coating solution in the form of an emulsified dispersion or a solid dispersion of fine particles and used in a light-sensitive material. The compound of the present invention forms a hydrogen bonding complex with a compound having a phenolic hydroxyl group and an amino group in a solution state, and is formed by a combination of a reducing agent and a compound represented by the general formula (D) of the present invention. Can be isolated in crystalline form as a complex. It is particularly preferable to use the crystal powder isolated in this manner as a solid dispersion fine particle dispersion in order to obtain stable performance. Further, the reducing agent and the general formula (D) of the present invention
A method in which the compound represented by the formula (1) is mixed with a powder and complexed at the time of dispersion with a sand grinder mill or the like using an appropriate dispersant can also be preferably used. The compound represented by formula (D) of the present invention is used in an amount of 1 to 200 with respect to the reducing agent.
It is preferably used in the range of 10 mol%, more preferably in the range of 10 to 150 mol%, and still more preferably 30 mol%.
１００100 mol%.

<Non-photosensitive Organic Silver Salt> The non-photosensitive organic silver salt which can be used in the present invention is relatively stable to light, but is exposed to an exposed photocatalyst (a latent image of a photosensitive silver halide). And the like, and a silver salt that forms a silver image when heated to 80 ° C. or higher in the presence of a reducing agent. The non-photosensitive organic silver salt can be any organic material including a source capable of reducing silver ions. Such a non-photosensitive organic silver salt is described in paragraph No. 00 of JP-A-10-62899.
48-0049, page 18, line 24 to page 19, line 37 of EP-A-0803764A1,
European Patent Publication No. 0962812 A1,
-34991, JP-A-2000-7683, 20
It is described in each publication of 00-72711. As the non-photosensitive organic silver salt in the invention, a silver salt of a long-chain aliphatic carboxylic acid (having 10 to 30 carbon atoms, preferably 15 to 28 carbon atoms) is particularly preferable. As the non-photosensitive organic silver salt, silver salts such as silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, and mixtures thereof are preferable. . In the present invention, among these non-photosensitive organic silver salts, it is preferable to use a non-photosensitive organic silver salt having a silver behenate content of 75 mol% or more. The shape of the non-photosensitive organic silver salt that can be used in the present invention is not particularly limited, and may be a needle shape, a rod shape, a flat plate shape, or a scale shape. In the present invention, scaly non-photosensitive organic silver salts are preferred. In the present specification, the scaly non-photosensitive organic silver salt is defined as follows. The silver salt of an organic acid was observed with an electron microscope, and the shape of the silver salt of the organic acid was approximated to a rectangular parallelepiped. The sides of the rectangular parallelepiped were designated as a, b, and c from the shortest side (c is the same as b). Then, calculation is performed using the shorter numerical values a and b, and x is obtained as follows. x = b / a

As described above, x is obtained for about 200 particles, and when an average value x (average) thereof is set as an average value x (average), those satisfying the relationship of x (average) ≧ 1.5 are regarded as scaly. Preferably 30 ≧ x (average) ≧ 1.5, more preferably 2
0 ≧ x (average) ≧ 2.0. By the way, needle shape is 1 ≦ x
(Average) <1.5.

In the scaly particles, a can be regarded as the thickness of tabular particles having a main plane with b and c as sides. The average of a is preferably 0.01 μm or more and 0.23 μm, more preferably 0.1 μm or more and 0.20 μm or less.
The average of c / b is preferably 1 or more and 6 or less, more preferably 1.05 or more and 4 or less, and further preferably 1.1 or more and 3 or less.
The value is particularly preferably 1.1 or more and 2 or less.

The particle size distribution of the non-photosensitive organic silver salt is preferably monodispersed. The monodispersion is preferably 100% or less, more preferably 80% or less, and still more preferably 50% of a value obtained by dividing the standard deviation of the length of each of the short axis and the long axis by each of the short axis and the long axis. It is as follows. The shape of the non-photosensitive organic silver salt can be measured from a transmission electron microscope image of the non-photosensitive organic silver salt dispersion.
Another method for measuring monodispersity is to determine the standard deviation of the volume-weighted average diameter of the non-photosensitive organic silver salt. The percentage (coefficient of variation) divided by the volume-weighted average diameter is preferably 100%. Or less, more preferably 80% or less, still more preferably 50% or less. As a measuring method, for example, a particle size (volume weighted average diameter) obtained by irradiating a laser beam to a non-photosensitive organic silver salt dispersed in a liquid and obtaining an autocorrelation function with respect to a time change of fluctuation of the scattered light. Can be obtained from

Known methods and the like can be applied to the production and dispersion method of the organic acid silver used in the present invention. For example, the above-mentioned JP-A-10-62899, European Patent Publication No. 0803763A1, and European Patent Publication No. 096281.
2A1, JP-A-11-34991, JP-A-2000
Nos. 7683 and 2000-72711, Japanese Patent Application Nos. 11-348228-30 and 11-20341.
No. 3, Japanese Patent Application No. 2000-90093, No. 2000-19
No. 5621, No. 2000-191226, No. 2000
-213813, 2000-214155, 2
000-191226 can be referred to.

When a non-photosensitive organic silver salt is dispersed in the presence of a photosensitive silver salt, fog increases and the sensitivity is remarkably reduced. More preferred. According to the present invention, the amount of the photosensitive silver salt in the aqueous dispersion to be dispersed is 0.1 mol% or less based on 1 mol of the organic acid silver salt in the liquid. Is not done.

In the present invention, a photothermographic material can be produced by mixing an aqueous dispersion of a non-photosensitive organic silver salt and an aqueous dispersion of a photosensitive silver salt. Can be selected according to the purpose, but the ratio of the photosensitive silver salt to the non-photosensitive organic silver salt is preferably in the range of 1 to 30 mol%, more preferably 3 to 20 mol%, particularly preferably 5 to 15 mol%. Is preferred. Mixing two or more aqueous dispersions of non-photosensitive organic silver salt and two or more aqueous dispersions of photosensitive silver salt at the time of mixing is a method preferably used for adjusting photographic characteristics.

[0104] Non-photosensitive organic silver salt of the present invention can be used in a desired amount, preferably 0.1-5 g / m ² as silver amount, more preferably from 1 to 3 g / m ^2.

<Other Development Accelerators> In the photothermographic material of the present invention, other development accelerators are disclosed in Japanese Patent Application No. 11-7.
Phenol derivatives represented by the formula (A) described in 3951 are preferably used.

<Explanation of Silver Halide> The photosensitive silver halide used in the present invention is not particularly limited in terms of the halogen composition. Silver chloride, silver chlorobromide, silver bromide, silver iodobromide, chloroiodide Silver halide can be used. Among them, silver bromide and silver iodobromide are preferred. The distribution of the halogen composition in the grains may be uniform, the halogen composition may change stepwise, or may change continuously. Further, silver halide grains having a core / shell structure can be preferably used. Preferred as the structure is a 2- to 5-fold structure, more preferably 2 to 4
Heavy core / shell particles can be used. Further, a technique of localizing silver bromide on the surface of silver chloride or silver chlorobromide grains can also be preferably used.

Methods for forming photosensitive silver halide are well known in the art and are described, for example, in Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458. Specifically, a photosensitive silver halide is prepared by adding a silver supply compound and a halogen supply compound to gelatin or another polymer solution, and then mixed with a non-photosensitive organic silver salt. Is used. Further, paragraphs 0217 to 02 of JP-A-11-119374 are used.
24, Japanese Patent Application No. 11-98708.
And Japanese Patent Application No. 2000-42336 are also preferable.

The grain size of the photosensitive silver halide is preferably small for the purpose of suppressing white turbidity after image formation, specifically, 0.20 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. The grain size as used herein refers to a diameter when converted into a circular image having the same area as the projected area of a silver halide grain (in the case of a tabular grain, the projected area of a main plane).

Examples of the shape of the silver halide grains include cubic, octahedral, tabular, spherical, rod-like and potato-like grains. In the present invention, cubic grains are particularly preferred. 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 grains is not particularly limited. However, the spectral sensitization efficiency when the spectral sensitizing dye is adsorbed is high. preferable. The ratio is preferably at least 50%, more preferably at least 65%, even more preferably at least 80%. The ratio of the {100} plane of the Miller index is determined by the T.M. Tani; Imaging
Sci. , 29, 165 (1985).

In the present invention, the hexacyano metal complex is
Silver halide grains present on the outermost surface of the particles are preferred. Six
Examples of the cyano metal complex include [Fe (CN)₆]^Four-, [F
e (CN)₆]^3-, [Ru (CN)₆]^Four-, [Os (C
N)₆]^Four-, [Co (CN)₆] ^3-, [Rh (CN)₆]
^3-, [Ir (CN)₆]^3-, [Cr (CN)₆]^3-, [R
e (CN)₆]^3-And the like. In the present invention
Hexacyano Fe complexes are preferred.

Since the hexacyano metal complex exists in the form of ions in an aqueous solution, the counter cation is not important. However, the hexacyano metal complex is easily miscible with water and is suitable for sodium ion and potassium ions which are suitable for the precipitation operation of a silver halide emulsion. Use of alkali metal ions such as ions, rubidium ions, cesium ions, and lithium ions, ammonium ions, and alkylammonium ions (for example, tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, and tetra (n-butyl) ammonium ion) Is preferred.

The hexacyano metal complex may be used in combination with water and a suitable water-miscible organic solvent (eg, alcohols, ethers, glycols, ketones, esters, amides, etc.) or gelatin. And can be added as a mixture.

The addition amount of the hexacyano metal complex is preferably from 1 × 10 ⁻⁵ mol to 1 × 10 ⁻² mol, more preferably from 1 × 10 ⁻⁴ mol to 1 × 10 ⁻³ mol per mol of silver. It is.

In order for the hexacyano metal complex to be present on the outermost surface of the silver halide grains, the addition of the hexacyano metal complex to the silver nitrate aqueous solution used for grain formation is followed by sulfur sensitization, selenium sensitization and tellurium sensitization. Is added directly before the completion of the charging step before the chemical sensitization step for precious metal sensitization such as chalcogen sensitization or gold sensitization, during the water washing step, during the dispersion step, or before the chemical sensitization step. In order not to grow the silver halide fine grains, it is preferable to add the hexacyano metal complex immediately after the grain formation, and it is preferable to add the hexacyano metal complex before the completion of the charging step.

Incidentally, the addition of the hexacyano metal complex may be started after 96% by mass of the total amount of silver nitrate added for grain formation, or started after 98% by mass is added. More preferably, it is particularly preferable after adding 99% by mass.

When these hexacyano metal complexes are added after the addition of an aqueous solution of silver nitrate immediately before the completion of grain formation, they can be adsorbed on the outermost surface of the silver halide grains, and most of them are hardly soluble in silver ions on the grain surface. Forms salt. Since the silver salt of hexacyanoiron (II) is a salt that is less soluble than AgI, it can be prevented from being redissolved by fine particles,
It has become possible to produce silver halide fine grains having a small grain size.

The photosensitive silver halide grains of the present invention can contain metals or metal complexes of Groups 8 to 10 of the periodic table (showing Groups 1 to 18). Rhodium, ruthenium, and iridium are preferably the metals of Groups 8 to 10 of the periodic table or the central metal of the metal complex. One kind of these metal complexes may be used, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is in the range of 1 × 10 ^-9 mol to 1 × 10 ^-3 mol per mol of silver. These heavy metals and metal complexes and their addition methods are described in paragraphs 0018 of JP-A-7-225449 and JP-A-11-65021.
To 0024, paragraphs 0227 to 0240 of JP-A-11-119374.

Further, metal atoms (for example, [Fe (C)) which can be contained in the silver halide grains used in the present invention.
N) ₆ ] ^4- ), the desalting method and the chemical sensitization method of the silver halide emulsion are described in paragraph No. 0 of JP-A-11-84574.
046-0050, paragraphs 0025-0031 of JP-A-11-65021, and JP-A-11-119374.
Nos. 0242 to 0250 in the publication.

As the gelatin contained in the photosensitive silver halide emulsion used in the present invention, various gelatins can be used. In order to maintain a good dispersion state of the photosensitive silver halide emulsion in the non-photosensitive organic silver salt-containing coating solution, it is preferable to use low molecular weight gelatin having a molecular weight of 500 to 60,000. These low molecular weight gelatins may be used at the time of grain formation or at the time of dispersion after desalting, but are preferably used at the time of dispersion after desalting.

The sensitizing dye applicable to the present invention is a sensitizing dye capable of spectrally sensitizing silver halide grains in a desired wavelength region when adsorbed on silver halide grains, and having a spectral sensitivity suitable for the spectral characteristics of an exposure light source. Can be advantageously selected. For sensitizing dyes and addition methods, see paragraphs 0103 to 010 of JP-A-11-65021.
9. General formula (II) of JP-A-10-186572
A dye represented by the general formula (I) and paragraph No. 0106 in JP-A-11-119374, U.S. Pat. Nos. 5,510,236 and 3,872.
Dyes described in Example 5 of JP-A No. 1,887,
Dyes disclosed in JP-A-96131 and JP-A-59-48753; European Patent Publication No. 0803764A.
No. 1, page 19, line 38 to page 20, page 35
Line, Japanese Patent Application No. 2000-86865, Japanese Patent Application No. 2000-10
2560 and Japanese Patent Application No. 2000-205399. These sensitizing dyes may be used alone or in combination of two or more. In the present invention, the time when the sensitizing dye is added to the silver halide emulsion is preferably after the desalting step and before coating, and more preferably after desalting and before the start of chemical ripening. The addition amount of the sensitizing dye in the present invention can be a desired amount according to the sensitivity and the performance of fogging, but is preferably 10 ^-6 to 1 mol, more preferably 1 mol per mol of silver halide in the photosensitive layer. Is 10 ^-4 to 10 ^-1 mol.

In the present invention, a supersensitizer can be used in order to improve the spectral sensitization efficiency. Examples of the supersensitizer used in the present invention include European Patent Publication No. 587,3.
No. 38, U.S. Pat. Nos. 3,877,943 and 4,873,184, JP-A-5-3414.
No. 32, No. 11-109947, No. 10-11154
Compounds described in the respective publications of No. 3 and the like can be mentioned.

The photosensitive silver halide grains in the present invention are preferably chemically sensitized by a sulfur sensitization method, a selenium sensitization method, or a tellurium sensitization method. As compounds preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds, for example, JP-A-7-12876
Compounds described in JP-A No. 8 and the like can be used.
Particularly in the present invention, tellurium sensitization is preferable.
Compounds described in the literature described in paragraph No. 0030 of 1-65021 and compounds represented by formulas (II), (III) and (IV) in JP-A-5-313284 are more preferred.

In the present invention, chemical sensitization can be performed at any time after grain formation and before coating. After desalting, (1) before spectral sensitization, (2) simultaneously with spectral sensitization, ( 3)
After spectral sensitization, there may be (4) just before coating. In particular, it is preferably performed after spectral sensitization. The amount of the sulfur, selenium and tellurium sensitizers used in the present invention varies depending on the silver halide grains to be used, the conditions of chemical ripening, etc., but is preferably 10 ^-8 to 10 ^-2 mol per mol of silver halide, preferably About 10 ^-7 to 10 ^-3 mol is used. The conditions of the chemical sensitization in the present invention are not particularly limited, but the pH is 5
-8, pAg as 6-11, temperature as 40-9
It is about 5 ° C. A thiosulfonate compound may be added to the silver halide emulsion used in the present invention by the method described in EP-A-293,917.

The light-sensitive silver halide emulsion in the light-sensitive material used in the present invention may be of one kind or two or more kinds (for example, those having different average grain sizes, different halogen compositions, different crystal habits). And those having different conditions of chemical sensitization). The gradation can be adjusted by using a plurality of photosensitive silver halides having different sensitivities.
Japanese Patent Application Laid-Open No. 57-119341 discloses a technique relating to these.
Nos. 53-106125, 47-3929, 48-55730, 46-5187, and 50-7
Nos. 3627 and 57-150841. The sensitivity difference was 0.2 lo for each emulsion.
It is preferable to have a difference of gE or more.

The amount of the photosensitive silver halide is 0.03, expressed as the amount of silver applied per m ^{2 of the} photothermographic material.
~ 0.6 g / m ² , preferably 0.07 ~
0.4 g / m ² is more preferable, and 0.05 g / m ² is more preferable.
Most preferably, it is ０．３0.3 g / m ² . For one mole of the non-photosensitive organic silver salt, the content of the photosensitive silver halide is 0.1%.
It is preferably from 01 mol to 0.5 mol, more preferably from 0.02 mol to 0.3 mol.

With respect to the mixing method and mixing conditions of the separately prepared photosensitive silver halide and non-photosensitive organic silver salt, the prepared silver halide particles and non-photosensitive organic silver salt were mixed with a high-speed stirrer, a ball mill, and the like. A method of mixing with a sand mill, a colloid mill, a vibration mill, a homogenizer, or the like, or a method of mixing a photosensitive silver halide prepared at any timing during the preparation of the non-photosensitive organic silver salt to mix the non-photosensitive organic silver salt There is no particular limitation as long as the effects of the present invention are sufficiently exhibited. In addition, mixing two or more aqueous dispersions of non-photosensitive organic silver salt and two or more aqueous dispersions of photosensitive silver salt is a preferable method for controlling photographic properties.

In the present invention, the preferable timing of adding the silver halide to the coating solution for the image forming layer is 18
The time is from 0 minutes to immediately before, preferably from 60 minutes to 10 seconds, but there is no particular limitation on the mixing method and mixing conditions as long as the effects of the present invention are sufficiently exhibited. As a specific mixing method, there is a method of mixing in a tank in which the average residence time calculated from the addition flow rate and the amount of liquid sent to the coater is set to a desired time, Harnby, M .; F. Ed
wards, A.M. W. Nienow, Translated by Koji Takahashi, "Liquid Mixing Technology" (Nikkan Kogyo Shimbun, 1989), 8th edition
There is a method using a static mixer or the like described in a chapter or the like.

<Binder> The binder for the organic silver salt-containing layer (that is, the image forming layer) of the present invention may be any polymer, and a suitable binder is transparent or translucent, generally colorless, and may be a natural resin or the like. Polymers and copolymers, synthetic resins, polymers and copolymers, and other film-forming media such as gelatins, rubbers, poly (vinyl alcohol) s, hydroxyethyl celluloses, cellulose acetates, cellulose acetate butyrate, poly (vinyl Pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), styrene-maleic anhydride copolymer, styrene-acrylonitrile Copolymers, styrene-butadiene copolymers, poly Vinyl acetal) (e.g., poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes),
There are phenoxy resins, poly (vinylidene chloride) s, poly (epoxides), poly (carbonates), poly (vinyl acetate) s, poly (olefins), cellulose esters, and poly (amides). The binder may be coated from water or an organic solvent or an emulsion.

In the present invention, the binder in the layer containing the organic silver salt has a glass transition temperature of preferably 10 ° C. or more and 80 ° C. or less (hereinafter, sometimes referred to as a high Tg binder), and more preferably 20 ° C. to 70 ° C. More preferably, 23
More preferably, it is not less than 65 ° C and not less than 65 ° C.

In the present specification, Tg was calculated by the following equation. 1 / Tg = Σ (Xi / Tgi) Here, it is assumed that the polymer is a copolymer of n monomer components from i = 1 to n. Xi is the weight fraction of the i-th monomer (ΣXi = 1), and Tgi is the glass transition temperature (absolute temperature) of the homopolymer of the i-th monomer.
Where Σ is the sum of i = 1 to n. The homopolymer glass transition temperature (Tgi) of each monomer is Pol
ymer Handbook (3rd Edition
n) (J. Brandrup, EH Immergu)
t (Wiley-Interscience, 198
9)) was adopted.

The polymer serving as the binder may be used alone or in combination of two or more as necessary.
Further, those having a glass transition temperature of 20 ° C. or higher and those having a glass transition temperature of less than 20 ° C. may be used in combination.
When two or more polymers having different Tg are blended and used, the weight average Tg is preferably in the above range.

In the present invention, when the organic silver salt-containing layer is formed by coating using a coating solution in which 30% by mass or more of water is water and then drying, the binder of the organic silver salt-containing layer is further added. The performance is improved when it is soluble or dispersible in an aqueous solvent (aqueous solvent), particularly when it is composed of a polymer latex having an equilibrium water content at 25 ° C. and 60% RH of 2% by mass or less. The most preferred form has an ionic conductivity of 2.5 m
It is prepared so as to be S / cm or less. As such a preparation method, a method of purifying using a separation functional membrane after polymer synthesis can be mentioned.

The aqueous solvent in which the polymer is soluble or dispersible is water or a mixture of water and 70% by mass or less of a water-miscible organic solvent. Examples of the water-miscible organic solvent include alcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol; cellosolves such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; ethyl acetate; and dimethylformamide.

The term "aqueous solvent" is used herein even in the case where the polymer is not thermodynamically dissolved but exists in a so-called dispersed state.

The “equilibrium water content at 25 ° C. and 60% RH” is defined as the weight W1 of the polymer in the moisture-conditioning equilibrium under the atmosphere of 25 ° C. and 60% RH and the weight W0 of the polymer in the dry state at 25 ° C. It can be expressed as follows. Equilibrium water content at 25 ° C. and 60% RH = ｛(W1-W
0) / W0｝ × 100 (% by mass)

The definition and measurement method of the water content can be referred to, for example, Polymer Engineering Course 14, Polymer Materials Testing Method (edited by The Society of Polymer Science, Jinjinshokan).

The binder polymer of the present invention at 25 ° C. 60
The equilibrium water content at% RH is preferably 2% by mass or less, more preferably 0.01% by mass or more and 1.5% by mass or less.
%, More preferably 0.02% by mass or more and 1% by mass or less.

In the present invention, a polymer dispersible in an aqueous solvent is particularly preferred. Examples of the dispersion state include a latex in which fine particles of a water-insoluble hydrophobic polymer are dispersed, and a dispersion in which polymer molecules are dispersed in a molecular state or in the form of micelles. The average particle size of the dispersed particles is 1 to 50,000 nm, more preferably 5 to 50000 nm.
A range of about to 1000 nm is preferable. There are no particular restrictions on the particle size distribution of the dispersed particles, and those having a wide particle size distribution or those having a monodispersed particle size distribution may be used.

In the present invention, preferred examples of the polymer dispersible in an aqueous solvent include acrylic polymers, poly (esters), rubbers (for example, SBR resin), poly (urethane) s, poly (vinyl chloride) s, Hydrophobic polymers such as poly (vinyl acetate) s, poly (vinylidene chloride) s and poly (olefins) can be preferably used. These polymers may be a linear polymer, a branched polymer, a crosslinked polymer, a so-called homopolymer obtained by polymerizing a single monomer, or a copolymer obtained by polymerizing two or more types of monomers. In the case of a copolymer, it may be a random copolymer or a block copolymer. These polymers have a number average molecular weight of 5,000 to 1,000,000, preferably 10,000 to 200,000. If the molecular weight is too small, the mechanical strength of the emulsion layer is insufficient, and if it is too large, the film-forming properties are poor, which is not preferable.

Specific examples of preferable polymer latex include the following. In the following, the raw material monomers are used, and the numerical value in parentheses is mass%, and the molecular weight is the number average molecular weight. When a polyfunctional monomer is used, the concept of molecular weight cannot be applied because a crosslinked structure is formed. Tg represents a glass transition temperature.

P-1; -MMA (70) -EA (27)
-MAA (3)-latex (molecular weight 37000) P-2; -MMA (70) -2EHA (20) -St
Latex of (5) -AA (5)-(molecular weight 4000
0) P-3; -St (50) -Bu (47) -MAA (3)
-Latex (crosslinkable) of P-4; -St (68) -Bu (29) -AA (3)-
Latex (crosslinkability) P-5; -St (71) -Bu (26) -AA (3)-
Latex (crosslinkable, Tg 24 ° C) P-6; -St (70) -Bu (27) -IA (3)-
Latex (crosslinkable) P-7; -St (75) -Bu (24) -AA (1)-
Latex (crosslinkable) P-8; -St (60) -Bu (35) -DVB (3)
-MAA (2)-latex (crosslinkable) P-9; -St (70) -Bu (25) -DVB (2)
-AA (3)-latex (crosslinkable) P-10; -VC (50) -MMA (20) -EA (2
Latex of 0) -AN (5) -AA (5)-(molecular weight: 80000) P-11; -VDC (85) -MMA (5) -EA
Latex of (5) -MAA (5)-(molecular weight 6700
0) Latex of P-12; -Et (90) -MAA (10)-(molecular weight 12000) P-13; -St (70) -2EHA (27) -AA
Latex of (3) (molecular weight 130000) P-14; -MMA (63) -EA (35) -AA
Latex of (2) (molecular weight 33000) P-15; -St (70.5) -Bu (26.5) -A
A (3) -latex (crosslinkable, Tg 23 ° C) P-16; -St (69.5) -Bu (27.5) -A
A (3) -latex (crosslinkable, Tg 20.5 ° C)

The abbreviations of the above structures represent the following monomers.
MMA; methyl methacrylate, EA; ethyl acrylate, MAA; methacrylic acid, 2EHA; 2-ethylhexyl acrylate, St; styrene, Bu; butadiene, AA; acrylic acid, DVB; divinylbenzene, VC; vinyl chloride, AN;
Acrylonitrile, VDC; vinylidene chloride, Et; ethylene, IA; itaconic acid.

The polymer latex described above is commercially available, and the following polymers can be used. Examples of acrylic polymers include Sebian A-463.
5,4718,4601 (Daicel Chemical Industries, Ltd.)
Nipol Lx811, 814, 821, 82
Examples of poly (esters) such as 0, 857 (all manufactured by Zeon Corporation) are FINETEX ES65.
Examples of poly (urethane) s such as 0, 611, 675, and 850 (all manufactured by Dainippon Ink and Chemicals, Inc.), WD-size, and WMS (all manufactured by Eastman Chemical) include HYDRAN AP10, 20, 30, Examples of rubbers such as 40 (all manufactured by Dainippon Ink and Chemicals, Inc.) include LACSTAR 7310K, 3307B, 470
0H, 7132C (Dai Nippon Ink Chemical Co., Ltd.)
Nipol Lx416, 410, 438C, 2
Examples of poly (vinyl chloride) such as 507 (manufactured by Nippon Zeon) include G351 and G576 (manufactured by Nippon Zeon); examples of poly (vinylidene chloride) include L502; L513 (Asahi Kasei Corporation)
Examples of poly (olefins) such as Chemipearl S120, SA100 (Mitsui Petrochemical Co., Ltd.)
Manufactured).

These polymer latexes may be used alone or may be blended as required.

The polymer latex used in the present invention is particularly preferably a styrene-butadiene copolymer latex. The mass ratio of the styrene monomer unit to the butadiene monomer unit in the styrene-butadiene copolymer is preferably from 40:60 to 95: 5. The proportion of the copolymer of styrene monomer units and butadiene monomer units is 60 to 99% by mass.
It is preferred that The preferred molecular weight range is the same as described above.

Styrene which is preferably used in the present invention
As the latex of butadiene copolymer, the above-mentioned P-
3-P-8, 14, 15; LACSTAR, a commercial product
−3307B, 7132C, Nipol Lx416 and the like.

The organic silver salt-containing layer of the light-sensitive material of the present invention may optionally contain a hydrophilic polymer such as gelatin, polyvinyl alcohol, methyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose and the like. The amount of these hydrophilic polymers to be added is 30% by mass or less, more preferably 20% by mass of the total binder in the organic silver salt-containing layer.
% By mass or less is preferred.

The organic silver salt-containing layer (that is, the image forming layer) of the invention is preferably formed using a polymer latex. As for the amount of the binder in the organic silver salt-containing layer, the mass ratio of total binder / organic silver salt is preferably in the range of 1/10 to 10/1, more preferably 1/5 to 4/1.

Further, such an organic silver salt-containing layer is usually a photosensitive layer (emulsion layer) containing a photosensitive silver halide, which is a photosensitive silver salt. / Mass ratio of silver halide is preferably in the range of 400 to 5, more preferably 200 to 10.

The total amount of the binder in the image forming layer of the present invention is:
Preferably 0.2 to 30 g / m ^2, the range of 1 to 15 g / m ² is more preferable. A crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like may be added to the image forming layer of the invention.

In the present invention, the solvent of the coating solution for the organic silver salt-containing layer of the light-sensitive material (the solvent and the dispersion medium are collectively referred to as a solvent for simplicity) is preferably an aqueous solvent containing 30% by mass or more of water. . As a component other than water, any water-miscible organic solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate may be used. The water content of the solvent in the coating liquid is preferably 50% by mass or more, more preferably 70% by mass or more. As an example of a preferable solvent composition, in addition to water, water / methyl alcohol =
90/10, water / methyl alcohol = 70/30, water /
Methyl alcohol / dimethylformamide = 80/15
/ 5, water / methyl alcohol / ethyl cellosolve = 85
/ 10/5, water / methyl alcohol / isopropyl alcohol = 85/10/5, etc. (numerical values are mass%).

<Description of Antifoggant> Antifoggant, stabilizer and stabilizer precursor usable in the present invention Paragraph 0070 of JP-A-10-62899 and No. 20 of European Patent Publication No. 0803764A1. Patents described on page 57, line 21 to page 21, line 7, JP-A-9-28
Compounds described in JP-A Nos. 1637 and 9-329864 are exemplified. The antifoggant preferably used in the present invention is an organic halide, which is described in paragraph No. 011 of JP-A-11-65021.
Patent Documents 1 to 0112 disclose those disclosed. In particular, an organic halogen compound represented by the formula (P) of Japanese Patent Application No. 11-87297,
An organic polyhalogen compound represented by the general formula (II) of JP-A-39934 and an organic polyhalogen compound described in Japanese Patent Application No. 11-205330 are preferred.

<Polyhalogen Compound> Preferred organic polyhalogen compounds used in the present invention will be specifically described below. The preferred polyhalogen compound of the present invention is a compound represented by the following general formula (H). General formula (H) Q- (Y) nC (Z ₁ ) (Z ₂ ) X In the general formula (H), Q represents an alkyl group, an aryl group, or a heterocyclic group. Y represents a divalent linking group.
n represents 0 or 1. Z ₁ and Z ₂ represent a halogen atom. X represents a hydrogen atom or an electron-withdrawing group. In the general formula (H), Q is a Hammett's substituent constant σp
Is preferably a phenyl group substituted with an electron-withdrawing group having a positive value. Regarding Hammett's substituent constant, see Journal of Medicinal Ch.
chemistry, 1973, Vol. 16, No. 1
1, 1207-1216 etc. can be referred to. Examples of such an electron-withdrawing group include a halogen atom (fluorine atom (σp value: 0.06), a chlorine atom (σ
p value: 0.23), bromine atom (σp value: 0.23), iodine atom (σp value: 0.18), trihalomethyl group (tribromomethyl (σp value: 0.29), trichloromethyl ( σp value: 0.33), trifluoromethyl (σ
p value: 0.54)), a cyano group (σp value: 0.66),
Nitro group (σp value: 0.78), aliphatic / aryl or heterocyclic sulfonyl group (eg, methanesulfonyl (σp value: 0.72)), aliphatic / aryl or heterocyclic acyl group (eg, acetyl (σp value) Value: 0.5
0), benzoyl (σp value: 0.43)), alkynyl group (eg, C≡CH (σp value: 0.23)), aliphatic / aryl or heterocyclic oxycarbonyl group (eg, methoxycarbonyl (σp value: : 0.45), phenoxycarbonyl (σp value: 0.44)), carbamoyl group (σp value: 0.36), sulfamoyl group (σp value:
0.57), a sulfoxide group, a heterocyclic group, a phosphoryl group and the like. The σp value is preferably in the range of 0.2 to 2.0, and more preferably in the range of 0.4 to 1.0. As the electron-withdrawing group, a carbamoyl group, an alkoxycarbonyl group, an alkylsulfonyl group, and an alkylphosphoryl group are particularly preferable, and among them, a carbamoyl group is most preferable. X is preferably an electron-withdrawing group, and is a halogen atom, an aliphatic / aryl or heterocyclic sulfonyl group, an aliphatic / aryl or heterocyclic acyl group, an aliphatic / aryl or heterocyclic oxycarbonyl group, a carbamoyl group, a sulfamoyl group. Is more preferable, and a halogen atom is particularly preferable. Among the halogen atoms, a chlorine atom, a bromine atom and an iodine atom are preferred, a chlorine atom and a bromine atom are more preferred, and a bromine atom is particularly preferred. Y is -C (= O)-, -SO-, or -SO ₂
Preferably, -C (= O) -, - SO 2 - is more preferable, -SO ₂ - is particularly preferred. N is 0 or 1, and preferably 1.

Hereinafter, specific examples of the compound represented by formula (H) will be shown.

[0155]

Embedded image

[0156]

Embedded image

In the present invention, the compound represented by the general formula (H) is preferably used in an amount of 10 ^-4 to 1 mol per 1 mol of the non-photosensitive silver salt in the image forming layer.
The range of 10 ^{−3 to} 0.8 mol is more preferred, and 5 × 10 ^−3.
More preferably, it is used in the range of 0.5 mol.
In the present invention, as a method for incorporating the antifoggant into the photothermographic material, the method described in the above-mentioned method for containing a reducing agent is exemplified, and it is preferable that the organic polyhalogen compound is also added in a solid fine particle dispersion. .

<Other antifoggants> Other antifoggants include mercury (II) salt of paragraph No. 0113 of JP-A-11-65021 and paragraph No. 01 of the same publication.
14, benzoic acids, a salicylic acid derivative of JP-A-2000-206664, a formalin scavenger compound represented by the formula (S) of JP-A-2000-221634, and a triazine according to claim 9 of JP-A-11-352624. Compounds, compounds represented by the general formula (III) in JP-A-6-11791, 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene and the like.

The photothermographic material of the present invention may contain an azolium salt for the purpose of preventing fog. Examples of the azolium salt include compounds represented by the general formula (XI) described in JP-A-59-193449, and JP-B-55-125.
No. 81, JP-A-60-153039
And the compound represented by the general formula (II) described in JP-A No. 6-1980. The azolium salt may be added to any part of the light-sensitive material, but it is preferable to add the azolium salt to the layer having the photosensitive layer, and to the non-photosensitive organic silver salt-containing layer (image forming layer). More preferably, The azolium salt may be added at any time during the preparation of the coating solution, and when the azolium salt is added to the non-photosensitive organic silver salt-containing layer (image forming layer), from the time of preparing the non-photosensitive organic silver salt to the time of preparing the coating solution. Any of the steps described above may be used, but is preferably performed after preparation of the non-photosensitive organic silver salt and immediately before coating. The azolium salt may be added by any method such as powder, solution, and fine particle dispersion. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent and a color tone agent. In the present invention, the addition amount of the azolium salt may be any amount, but is preferably 1 × 10 ⁻⁶ mol or more and 2 mol or less, more preferably 1 × 10 ⁻³ mol or more and 0.5 mol or less per 1 mol of silver.

The photothermographic material of the present invention may contain a mercapto compound, a disulfide compound or the like for controlling development by suppressing or accelerating development, improving spectral sensitization efficiency, and improving storage stability before and after development. And a thione compound.
Paragraph Nos. 0067 to 0069 of JP-A No.
No. 86572, compounds represented by the general formula (I) and specific examples thereof, paragraphs [0033] to [0052], and EP2080364A1, page 20, page 3
It is described in Japanese Patent Application No. 11-273670, line 6-56. Among them, mercapto-substituted heteroaromatic compounds are preferred.

<Color Toning Agent> In the photothermographic material of the present invention, it is preferable to add a color toning agent.
Paragraph Nos. 0054 to 0055 of U.S. Pat. No. 628899, page 23 to line 48 of European Patent Publication No. 0803764A1, described in JP-A-2000-356317 and Japanese Patent Application No. 2000-187298, In particular, phthalazinones (phthalazinone, phthalazinone derivatives or metal salts; for example, 4- (1-naphthyl)
Phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione; phthalazinones and phthalic acids (for example, phthalic acid, 4-methylphthalic acid, 4- Combination with nitrophthalic acid, diammonium phthalate, sodium phthalate, potassium phthalate and tetrachlorophthalic anhydride; phthalazines (phthalazine, phthalazine derivative or metal salt; for example, 4- (1-naphthyl) phthalazine, 6-isopropyl Phthalazine, 6-t-butylfuratazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine); a combination of phthalazines and phthalic acids is preferred, and phthalazines and phthalates are particularly preferred. Combinations of acids are preferred.

<Other Additives> Plasticizers and lubricants that can be used in the photosensitive layer of the present invention are described in
Paragraph No. 0117 of 1-65021, the ultra-high contrast agent for forming a super-high contrast image, and the addition method and amount thereof are described in paragraph No. 0118 of the same publication, JP-A No. 11-223.
No. 8136, paragraphs 0136 to 0193, Japanese Patent Application No. 1
Formula (H), Formulas (1) to (3) of 1-87297,
Compounds represented by formulas (A) and (B), Japanese Patent Application No. 11-91
No. 652, the compounds represented by the general formulas (III) to (V) (specific compounds: Chemical formulas 21 to 24) and the contrast enhancement accelerator are described in paragraph No. 01 of JP-A-11-65021.
02, paragraph number 01 of JP-A-11-223898
94-0195.

In order to use formic acid or formate as a strong fogging substance, it must be contained in an amount of 5 mmol or less, more preferably 1 mmol or less, per mole of silver on the side having the image forming layer containing photosensitive silver halide. Is preferred.

When a super-high contrast agent is used in the photothermographic material of the present invention, it is preferable to use an acid or a salt thereof formed by hydration of diphosphorus pentoxide in combination. Acids or salts thereof formed by hydration of diphosphorus pentoxide include metaphosphoric acid (salt), pyrophosphoric acid (salt), orthophosphoric acid (salt), triphosphoric acid (salt), tetraphosphoric acid (salt), hexametaline Acid (salt)
And the like. Particularly preferred acids or salts thereof formed by hydration of diphosphorus pentoxide include orthophosphoric acid (salt) and hexametaphosphoric acid (salt). Specific salts include sodium orthophosphate, sodium dihydrogen orthophosphate, sodium hexametaphosphate, ammonium hexametaphosphate and the like. Diphosphorus pentoxide or acid obtained by hydration, the amount of a salt thereof (per photosensitive material 1 m ² coating weight) may be desired amount depending on the performance such as sensitivity and fog, 0.1 to 50
Preferably ^{0mg / m 2, 0.5~100mg / m} 2 is more preferable.

(Description of Layer Structure) The layer structure of the photothermographic material of the present invention will be described below. The photothermographic material of the present invention can be provided with a surface protective layer for the purpose of preventing adhesion of the image forming layer. The surface protective layer may be a single layer or a plurality of layers. The surface protective layer is described in paragraphs 0119 to 01 of JP-A-11-65021.
20, Japanese Patent Application No. 2000-171936. Gelatin is preferable as the binder of the surface protective layer of the present invention, but it is also preferable to use polyvinyl alcohol (PVA) or to use it in combination. As gelatin, inert gelatin (for example, Nitta Gelatin 750), phthalated gelatin (for example, Nitta Gelatin 801) and the like can be used. As PVA, JP-A-2000-1
No. 71936, paragraphs 0009 to 0020, which include PVA-105 as a completely saponified product, PVA-205 and PVA-335 as partially saponified products, and MP-203 as a modified polyvinyl alcohol (Kuraray Co., Ltd.) And the like). Preferably 0.3 to 4.0 g / m ² as a coating amount of polyvinyl alcohol protective layer (per one layer) (per support 1 m ^2),
0.3-2.0 g / m < ² > is more preferable.

In particular, when the photothermographic material of the present invention is used for printing in which dimensional change is a problem, it is preferable to use a polymer latex for the surface protective layer and the back layer. For such polymer latex, see "Synthetic Resin Emulsion (edited by Tadashi Okuda and Hiroshi Inagaki, published by Polymer Publishing Association (1978))", "Application of Synthetic Latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Keiji Kasahara, edited by Keiji Kasahara) Molecular publishing society (1993)), "Synthesis of synthetic latex (Souichi Muroi, published by Kobunshi Kankokai (1970))" and the like, and specifically, methyl methacrylate (33.5% by mass) / Ethyl acrylate (50% by weight) / latex of methacrylic acid (16.5% by weight) copolymer, methyl methacrylate (47.5% by weight) / butadiene (4
Latex of 7.5% by mass) / itaconic acid (5% by mass) copolymer, latex of ethyl acrylate / methacrylic acid copolymer, methyl methacrylate (58.9%)
Mass%) / 2-ethylhexyl acrylate (25.4
Mass%) / styrene (8.6 mass%) / 2-hydroxyethyl methacrylate (5.1 mass%) / latex of acrylic acid (2.0 mass%) copolymer, methyl methacrylate (64.0 mass%) / styrene Latex of (9.0% by mass) / butyl acrylate (20.0% by mass) / 2-hydroxyethyl methacrylate (5.0% by mass) / acrylic acid (2.0% by mass). Further, as a binder for the surface protective layer, a combination of a polymer latex described in Japanese Patent Application No. 11-6872, a technique described in paragraph Nos.
The technology described in paragraph Nos. 0027 to 0028 of Japanese Patent Application No. -6872 and the technology described in paragraph Nos. 0023 to 0041 of Japanese Patent Application No. 10-199626 may be applied.
The ratio of the polymer latex in the surface protective layer is preferably from 10% by weight to 90% by weight of the total binder, and more preferably 20% by weight or less.
It is preferably from 80% by weight to 80% by weight. Surface protective layer (1
All containing binder (water-soluble polymer and latex polymer) preferably 0.3 to 5.0 g / m ² as a coating amount (per support 1 m ²⁾ of layers per), 0.3
2.0 g / m ² is more preferred.

The preparation temperature of the coating solution for the image forming layer in the present invention is preferably 30 ° C. to 65 ° C., more preferably 35 ° C. to less than 60 ° C., and more preferably 35 ° C. to 55 ° C. Further, the temperature of the image forming layer coating solution immediately after the addition of the polymer latex is preferably maintained at 30 ° C. or higher and 65 ° C. or lower.

The image forming layer in the present invention comprises one or more layers on a support. When it is composed of one layer, it comprises a non-photosensitive organic silver salt, a light-sensitive silver halide, a reducing agent and a binder, and if necessary, contains additional materials such as a toning agent, a coating aid and other auxiliary agents as required. When it comprises two or more layers, the first image-forming layer (usually a layer adjacent to the support) contains a non-photosensitive organic silver salt and a photosensitive silver halide, and the second image-forming layer or both layers Must contain some other ingredients. The construction of a multicolor photothermographic material may include a combination of these two layers for each color, and all components in a single layer as described in U.S. Pat. No. 4,708,928. May be included. In the case of a multi-dye, multi-color photothermographic material, each emulsion layer generally comprises a functional or non-functional layer between the light-sensitive layers, as described in U.S. Pat. No. 4,460,681. Are kept distinct from each other by using the barrier layer.

In the photosensitive layer of the present invention, various dyes and pigments (for example, CI Pigment) are used from the viewpoint of color tone improvement, prevention of interference fringe generation during laser exposure, and prevention of irradiation.
Blue 60, C.I. I. Pigment Blue
64, C.I. I. Pigment Blue 15: 6)
Can be used. About these, WO98 / 3
6322, JP-A-10-268465, 11-3
No. 38098 and the like.

In the photothermographic material of the present invention, an antihalation layer can be provided on the side farther from the light source than the photosensitive layer.

A photothermographic material generally has a non-photosensitive layer in addition to a photosensitive layer. The non-photosensitive layer may be arranged in such a manner that (1) a protective layer provided on the photosensitive layer (on the side farther than the support), (2) between a plurality of photosensitive layers or between the photosensitive layer and the protective layer. (3) an undercoat layer provided between the photosensitive layer and the support, and (4) a back layer provided on the opposite side of the photosensitive layer. The filter layer is
It is provided on the photosensitive material as the layer (1) or (2). The antihalation layer is provided on the photosensitive material as the layer (3) or (4).

The antihalation layer is described in paragraphs 0123 to 012 of JP-A-11-65021.
4, JP-A-11-223898, 9-230531
No., No. 10-36695, No. 10-104779,
Nos. 11-231457, 11-352625, and 11-352626. The antihalation layer contains an antihalation dye having absorption at the exposure wavelength. When the exposure wavelength is in the infrared region, an infrared absorbing dye may be used, and in that case, a dye having no absorption in the visible region is preferable. When using a dye having absorption in the visible region to prevent halation, it is preferable that substantially no color of the dye remains after image formation, and a means for decoloring by the heat of heat development is used. It is particularly preferable to add a thermal decoloring dye and a base precursor to the non-photosensitive layer to function as an antihalation layer. These techniques are described in, for example, JP-A-11-231457.

The amount of the decolorizable dye is determined depending on the use of the dye. Generally, the optical density (absorbance) measured at the target wavelength is used in an amount exceeding 0.1. The optical density is preferably from 0.2 to 2. The amount of the dye used to obtain such an optical density is generally 0.00
It is about 1 to 1 g / m ² .

When the dye is decolored in this manner, the optical density after thermal development can be reduced to 0.1 or less. Two or more decolorizable dyes may be used in combination in a heat-decolorable recording material or a photothermographic material. Similarly, two or more base precursors may be used in combination. In thermal decoloring using such a decoloring dye and a base precursor,
The use of a substance (e.g., diphenylsulfone, 4-chlorophenyl (phenyl) sulfone) which lowers the melting point by 3 [deg.] C. (deg) or more when mixed with a base precursor as described in JP-A-11-352626 can be used in combination with thermal decoloration. It is preferable from the point of view.

In the present invention, a colorant having an absorption maximum at 300 to 450 nm can be added for the purpose of improving the silver tone and the aging of the image. Such coloring agents are described in JP-A-62-210458 and JP-A-63-10404.
No. 6, No. 63-103235, No. 63-208846
Nos. 63-306436 and 63-314535
And Japanese Patent Application Laid-Open No. 01-61745.
-2766751 and the like. Such a coloring agent is usually added in the range of 0.1 mg / m ^{2 to 1} g / m ² , and the layer to be added is preferably a back layer provided on the side opposite to the photosensitive layer.

The photothermographic material of the present invention is a so-called single-sided light-sensitive material having at least one photosensitive layer containing a silver halide emulsion on one side of a support and a back layer on the other side. Preferably, there is.

In the present invention, it is preferable to add a matting agent for improving transportability. About matting agent,
Paragraph Nos. 0126-0 of JP-A-11-65021
127. Matting agent, 1m ^{2 of} photosensitive material
If indicated by the coating amount per, preferably 1 to 400 mg / m ^2, preferably from 5 to 300 mg / m ^2. Also,
The matt degree of the emulsion surface may be any value as long as no stardust failure occurs, but the Beck smoothness is preferably 30 seconds or more and 2000 seconds or less, and particularly preferably 40 seconds or more and 1500 seconds or less. The Beck smoothness is determined by the Japanese Industrial Standards (JIS) P8119 “Smoothness test method of paper and paperboard using Beck tester” and T
It can be easily determined by APPI standard method T479. The matting degree of the back layer in the present invention is preferably such that the Beck smoothness is 1200 seconds or less and 10 seconds or more,
It is preferably 0 seconds or less and 20 seconds or more, more preferably 500 seconds or less and 40 seconds or more.

In the present invention, the matting agent is preferably contained in the outermost surface layer of the light-sensitive material, a layer functioning as the outermost surface layer, or a layer close to the outer surface, and a layer functioning as a so-called protective layer. Is preferably contained. The back layer applicable to the invention is described in paragraph No. 0128 of JP-A-11-65021.
To 0130.

The photothermographic material of the present invention preferably has a pH of 7.0 or less, more preferably 6.6 or less, before the heat development. The lower limit is not particularly limited, but is about 3. The most preferred pH range is between 4 and
6.2. The adjustment of the film surface pH is preferably performed using an organic acid such as a phthalic acid derivative, a non-volatile acid such as sulfuric acid, or a volatile base such as ammonia from the viewpoint of reducing the film surface pH. In particular, ammonia is preferable in achieving a low film surface pH since ammonia is easily volatilized and can be removed before the application step and the heat development. It is also preferable to use ammonia in combination with a non-volatile base such as sodium hydroxide, potassium hydroxide, and lithium hydroxide. The method for measuring the pH of the film surface is described in Japanese Patent Application No. 11-8 / 1999.
No. 7297, paragraph 0123.

A hardener may be used in each layer such as the emulsion layer (photosensitive layer), the protective layer and the back layer of the present invention. Examples of the hardener include T.V. H. James "THE THEOR"
YOF THE PHOTOGRAPHIC PROC
ESS FOURTH EDITION "(Macmi
lan Publishing Co. , Inc.
Published in 1977), pages 77 to 87, which include chrome alum, 2,4-dichloro-6-hydroxy-s-triazine sodium salt, N, N-ethylenebis (vinylsulfoneacetamide), N , N-propylenebis (vinylsulfoneacetamide),
Polyvalent metal ions described in p. 78 of the same book, US Pat.
Polyisocyanates such as 81,060 and JP-A-6-208193, epoxy compounds such as U.S. Pat. No. 4,791,042, and JP-A-62-2904.
Vinyl sulfone compounds such as those described in JP-A No. 8 are preferably used.

The hardener is added as a solution, and the time of adding this solution to the coating solution for the protective layer is from 180 minutes to immediately before coating, preferably from 60 minutes to 10 seconds before coating. The mixing conditions are not particularly limited as long as the effects of the present invention are sufficiently exhibited. As a specific mixing method, there is a method of mixing in a tank in which the average residence time calculated from the addition flow rate and the amount of liquid sent to the coater is set to a desired time, Harnby, M .; F. Edw
ards, A .; W. There is a method using a static mixer or the like described in Chapter 8 of Nienow, "Liquid Mixing Technology" translated by Koji Takahashi (Nikkan Kogyo Shimbun, 1989).

The surfactant applicable to the present invention is described in JP-A-11-65021, paragraph number 013.
2. Paragraph No. 0133 of the publication for the solvent, paragraph 0134 of the publication for the support, paragraph 0135 of the publication for the antistatic or conductive layer, and paragraph 0136 of the publication for the method of obtaining a color image. The slip agents are described in paragraphs [0061] to [0064] of JP-A No. 11-84573 and paragraphs [0049] to [0062] of JP-A No. 11-106881.

The transparent support was subjected to a heat treatment at a temperature in the range of 130 to 185 ° C. in order to alleviate the internal strain remaining in the film during the biaxial stretching and to eliminate the heat shrinkage distortion generated during the heat development. Polyester, especially polyethylene terephthalate, is preferably used. In the case of a photothermographic material for medical use, the transparent support may be colored with a blue dye (for example, Dye-1 described in Examples of JP-A-8-240877) or may be uncolored. The support includes
A water-soluble polyester disclosed in JP-A-11-84574;
Styrene butadiene copolymer disclosed in JP-A-10-186565, JP-A-2000-39684 and Japanese Patent Application No.
It is preferable to apply an undercoating technique such as a vinylidene chloride copolymer of paragraphs [0063] to [0080] of Japanese Patent No. 106881. Further, regarding the antistatic layer or the undercoat, JP-A-56-143430 and JP-A-56-143431.
Nos. 58-62646 and 56-120519, paragraph No. 00 of JP-A-11-84573.
40-0051, U.S. Pat. No. 5,575,957, Paragraph 007 of JP-A-11-223898.
The techniques described in 8-0084 can be applied.

The photothermographic material of the present invention is preferably of a monosheet type (a type capable of forming an image on the photothermographic material without using another sheet such as an image receiving material).

The photothermographic material may further contain an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber or a coating aid. Various additives are added to either the photosensitive layer or the non-photosensitive layer. W about them
O98 / 36322, EP803764A1, JP-A-10-186567 and JP-A-10-18568 can be referred to.

The photothermographic material of the present invention may be applied by any method. Specifically, extrusion coating, slide coating, curtain coating, dip coating, knife coating, flow coating, or US Pat.
A variety of coating operations are used, including extrusion coating using a hopper of the type described in US Pat. Kistler, Peter
tM. "LIQUIDFIL" by Schweizer
M COATING "(CHAPMAN & HALL
Extrusion coating or slide coating described on pages 399 to 536 (published by company, 1997) is preferably used, and particularly preferably slide coating is used. An example of the shape of a slide coater used for slide coating is shown in FIG.
e 11b. There is one. 399, ibid.
Pp. 536, US Pat. No. 2,761,7
Two or more layers can be coated simultaneously by the methods described in US Pat. No. 91 and GB 837,095.

The coating solution for the non-photosensitive organic silver salt-containing layer (image forming layer) in the present invention is preferably a so-called thixotropic fluid. This technology is disclosed in
Reference can be made to JP-A-52509. The non-photosensitive organic silver salt-containing layer (image forming layer) coating solution of the invention has a viscosity of 400 mPa · s at a shear rate of 0.1 S ⁻¹ .
Is preferably not less than 100,000 mPa · s, more preferably not less than 500 mPa · s and 20,000 mPa · s.
s or less. Further, at a shear rate of 1000 S ^−1, it is preferably from 1 mPa · s to 200 mPa · s, and more preferably from 5 mPa · s to 80 mPa · s.

Techniques that can be used in the photothermographic material of the present invention include EP803376A1 and EP88376.
No. 3022A1, WO98 / 36322, JP-A-56
-62648, 58-62644, JP-A-9-4
3766, 9-281637, 9-297367
No. 9-304869, No. 9-31405, No. 9-329865, No. 10-10669, No. 10-
No. 62899, No. 10-69023, No. 10-186
No. 568, No. 10-90823, No. 10-17106
No. 3, No. 10-186565, No. 10-186567
Nos. 10-186569 to 10-186572
No. 10-197974, No. 10-197982
No. 10-197983, No. 10-197985 to No. 10-197987, No. 10-207001,
Nos. 10-207004, 10-221807, 10-282601, 10-288823, 1
Nos. 0-288824, 10-307365, and 10
No.-312038, No.10-339934, No.11-
No. 7100, No. 11-15105, No. 11-2420
No. 0, No. 11-24201, No. 11-30832,
11-84574, 11-65021, 11
Nos. 109547, 11-125880, 11-
Nos. 129629 and 11-133536 to 11-1
No. 33538, No. 11-133542, No. 11-13
No. 3543, No. 11-223898, No. 11-352
No. 627, No. 11-305377, No. 11-3053
No. 78, No. 11-305384, No. 11-30538
No. 0, No. 11-316435, No. 11-327076
No. 11-338096 and No. 11-338098
Nos. 11-338099 and 11-343420, Japanese Patent Application Nos. 2000-187298 and 2000
No.-10229, No.2000-47345, No.200
Nos. 0-206642, 2000-98530, 2
000-98531, 2000-112059,
No. 2000-112060, No. 2000-11210
No. 4, No. 2000-112064, No. 2000-17
Each specification of 1936 is also mentioned.

(Explanation of Thermal Development) The photothermographic material of the present invention may be developed by any method. Usually, the photothermographic material exposed imagewise is heated and developed.
The development temperature is preferably from 80 to 250 ° C.
~ 140 ° C is more preferred. The development time ranges from 1 to
60 seconds is preferable, 5 to 30 seconds is more preferable, and 10 seconds
-20 seconds is particularly preferred.

As a method of thermal development, a plate heater method is preferable. The heat development method using a plate heater method is a method described in Japanese Patent Application Laid-Open No. H11-133572 and the like. Wherein the heating means comprises a plate heater, and a plurality of pressing rollers are disposed to face each other along one surface of the plate heater, and a heating roller is provided between the pressing roller and the plate heater. A heat developing apparatus for performing heat development by passing the photothermographic material. The plate heater is divided into 2 to 6 stages, and the tip is 1 to 1
It is preferable to lower the temperature by about 0 ° C. Such a method is also described in JP-A-54-30032,
Moisture and organic solvents contained in the photothermographic material can be excluded from the system, and changes in the shape of the support of the photothermographic material due to rapid heating of the photothermographic material can be suppressed. You can also.

The photothermographic material of the present invention may be exposed 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 (Ar ⁺ , He—Ne), a YAG laser, a dye laser, a semiconductor laser, or the like is preferable. Further, a semiconductor laser and a second harmonic generation element can be used. Preferably, a gas or semiconductor laser emitting red to infrared light is used.

As a medical laser imager having an exposure section and a heat development section, Fuji Medical Dry Laser Imager FM-DPL can be mentioned. Regarding FM-DPL, Fuji Medic
al Review No. 8, page 39-55
It goes without saying that those techniques are applied as a laser imager for the photothermographic material of the present invention. Further, the present invention can also be applied as a photothermographic material for a laser imager in "AD network" proposed by Fuji Medical System as a network system conforming to the DICOM standard.

The photothermographic material of the present invention forms a black-and-white image by a silver image, and is used for medical diagnosis, photothermographic material for industrial photography, photothermographic material for printing, COM
It is preferably used as a photothermographic material for use.

[0194]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 (Preparation of PET support) Using terephthalic acid and ethylene glycol, an intrinsic viscosity IV = 0.66 (phenol / tetrachloroethane = 6/4 (mass ratio) 25)
(Measured in ° C.). After pelletizing this 1
It was dried at 30 ° C. for 4 hours, melted at 300 ° C., extruded from a T-die, and quenched to prepare an unstretched film having a thickness of 175 μm after heat setting. This was longitudinally stretched 3.3 times using rolls having different peripheral speeds, and then horizontally stretched 4.5 times using a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After this, 240 ° C
After heat setting for 20 seconds, the film was relaxed 4% in the horizontal direction at the same temperature. After slitting the chuck part of the tenter,
Performs a knurled at both ends, wound up at 4kg / cm ^2,
A roll having a thickness of 175 μm was obtained.

(Surface Corona Treatment) Using a solid state corona treatment machine 6KVA model manufactured by Pillar Co., both surfaces of the support were treated at room temperature at 20 m / min. From the current and voltage readings at this time, 0.375 kV was applied to the support.
-It turned out that the processing of A * minute / m < ² > was performed.
The processing frequency at this time is 9.6 kHz, and the electrode and the dielectric
The gap clearance of the shell was 1.6 mm.

(Preparation of Undercoating Support) << Preparation of Undercoating Layer Coating Solution >> Formulation (for Undercoating Layer on Photosensitive Layer Side) Takamatsu Oil Co., Ltd. Pesresin A-515GB (30% by mass solution) 234 g Polyethylene glycol monononylphenyl 21.5 g of ether (average ethylene oxide number = 8.5) 10% by mass solution 0.91 g of Soken Chemical Co., Ltd. MP-1000 (polymer fine particles, average particle diameter 0.4 μm) distilled water 744 ml

Formulation (for back layer first layer) Styrene-butadiene copolymer latex 158 g (solid content 40% by mass, styrene / butadiene mass ratio = 68/32) 2,4-dichloro-6-hydroxy-S-20 g 8% by weight aqueous solution of triazine sodium salt 1% by weight aqueous solution of sodium laurylbenzenesulfonate 10ml Distilled water 854ml

Formulation (for back surface side second layer) SnO ₂ / SbO (9/1 mass ratio, average particle size 0.038 μm, 17 mass% dispersion) 84 g gelatin (10 mass% aqueous solution) 89.2 g Shin-Etsu Chemical ( 8.6 g of Metrolose TC-5 (2% by weight aqueous solution) manufactured by Soken Chemical Co., Ltd. 0.01 g 1% by weight aqueous solution of sodium dodecylbenzenesulfonate 10 ml NaOH (1% by weight) 6 ml 1ml distilled water 805ml

<< Preparation of Undercoating Support >> Thickness 175
After performing the above-described corona discharge treatment on both surfaces of the biaxially stretched polyethylene terephthalate support having a thickness of μm, the undercoating solution formulation was coated on one surface (the surface of the photosensitive layer) with a wire bar at a wet application amount of 6.6 ml / m ² ( Per side)
And dried at 180 ° C. for 5 minutes. Then, the undercoating solution formulation was applied to the back surface (back surface) with a wire bar so that the wet application amount was 5.7 ml / m ^2, and After drying at 5 ° C. for 5 minutes, the above-mentioned undercoat coating solution was further applied to the back surface (back surface) with a wire bar so that the wet application amount was 7.7 ml / m ^2.
After drying at 80 ° C. for 6 minutes, an undercoat support was prepared.

(Preparation of Back Surface Coating Solution) << Preparation of Solid Precursor Dispersion (a) of Base Precursor >>>> 64 g of base precursor compound 11, 28 g of diphenylsulfone, and 10 g of Demol N surfactant manufactured by Kao Corporation The mixture was mixed with 220 ml of distilled water, and the mixture was dispersed in beads using a sand mill (1/4 Gallon sand grinder mill, manufactured by Imex Co., Ltd.), and a dispersion of solid fine particles of a base precursor compound having an average particle diameter of 0.2 μm (a ) Got.

<< Preparation of Dye Solid Fine Particle Dispersion >> 9.6 g of the cyanine dye compound 13 and 5.8 g of sodium p-dodecylbenzenesulfonate were mixed with 305 ml of distilled water, and the mixture was subjected to a sand mill (1/4 Gallon sand grinder mill). The dispersion was carried out using beads (manufactured by IMEX Co., Ltd.) to obtain a dye solid fine particle dispersion having an average particle diameter of 0.2 μm.

<< Preparation of Coating Solution for Anti-Halation Layer >> 17 g of gelatin, 9.6 g of polyacrylamide, 70 g of solid fine particle dispersion (a) of the base precursor, 56 g of solid fine particle dispersion of dye, and monodispersed polymethyl methacrylate fine particles (average) Particle size 8 μm, particle size standard deviation 0.
4) 1.5 g, benzoisothiazolinone 0.03 g, sodium polyethylene sulfonate 2.2 g, blue dye compound 14 0.2 g, yellow dye compound 15 3.9
g and water (844 ml) were mixed to prepare an antihalation layer coating solution.

<< Preparation of back surface protective layer coating solution >>
Heated to 0 ° C., gelatin 50 g, polystyrene sodium sulfonate 0.2 g, N, N-ethylenebis (vinylsulfoneacetamide) 2.4 g, sodium t-octylphenoxyethoxyethaneethanesulfonate 1
g, benzoisothiazolinone 30 mg, fluorine-based surfactant (F-1: potassium N-perfluorooctylsulfonyl-N-propylalanine salt) 37 mg, fluorine-based surfactant (F-2: polyethylene glycol mono (N- 0.15 g of perfluorooctylsulfonyl-N-propyl-2-aminoethyl) ether [average degree of polymerization of ethylene oxide 15]), a fluorine-based surfactant (F
-3) 64 mg, Fluorine alert surfactant (F-4) 32 m
g, acrylic acid / ethyl acrylate copolymer (copolymer mass ratio 5/95) 8.8 g, aerosol OT (manufactured by American Cyanamid Co.) 0.6 g, liquid paraffin emulsion 1.8 g as liquid paraffin, 950 ml of water was mixed to obtain a back surface protective layer coating solution.

(Preparation of silver halide emulsion) << Preparation of silver halide emulsion 1 >> 1 in 1421 ml of distilled water
A 3.1% by weight potassium bromide solution (3.1 ml) was added, followed by 0.1 ml.
While stirring a solution containing 3.5 ml of 5 mol / L sulfuric acid and 31.7 g of phthalated gelatin in a stainless steel reaction bottle, the solution temperature was maintained at 30 ° C., and distilled water was added to 22.22 g of silver nitrate. A solution (solution A) diluted to 95.4 ml and a solution (solution B) obtained by diluting 15.3 g of potassium bromide and 0.8 g of potassium iodide to a volume of 97.4 ml with distilled water at a constant flow rate for 45 seconds. The whole amount was added. Then, 3.
10 ml of a 5% by mass aqueous hydrogen peroxide solution was added, and 10.8 ml of a 10% by mass aqueous solution of benzimidazole was further added.
Was added. Further, a solution (solution C) prepared by adding distilled water to 51.86 g of silver nitrate to 317.5 ml (solution C) and a solution prepared by diluting 44.2 g of potassium bromide and 2.2 g of potassium iodide to a volume of 400 ml with distilled water (solution) D) was added to the solution C at a constant flow rate over 20 minutes, and the solution D was pAg
Was added by the controlled double jet method while maintaining at 8.1. The total amount of potassium hexachloride iridate (III) was added 10 minutes after starting to add the solution C and the solution D so as to be 1 × 10 ⁻⁴ mol per mol of silver.
Five seconds after the completion of the addition of the solution C, iron hexacyanide (I
I) An aqueous solution of potassium was added in a total amount of 3 × 10 ^-4 mol per mol of silver. The pH was adjusted to 3.8 with 0.5 mol / L sulfuric acid, the stirring was stopped, and the sedimentation / desalting / water washing steps were performed. The pH was adjusted to 5.9 with 1 mol / L sodium hydroxide to prepare a silver halide dispersion having a pAg of 8.0.

While stirring the above silver halide dispersion, 3
While maintaining at 8 ° C., 5 ml of a 0.34 mass% 1,2-benzisothiazolin-3-one methanol solution was added,
After 40 minutes, the molar ratio of spectral sensitizing dye A to sensitizing dye B is 1:
The methanol solution of No. 1 was added in an amount of 1.2 × 10 ⁻³ mol as the total of sensitizing dyes A and B per mol of silver, and the temperature was raised to 47 ° C. one minute later. Twenty minutes after the temperature was raised, sodium benzenethiosulfonate was dissolved in a methanol solution at 7.6 with respect to 1 mol of silver.
× 10 ^-5 mol was added, and 5 minutes later, 2.9 × 10 ^-4 mol of tellurium sensitizer B was added per mol of silver with a methanol solution, followed by ripening for 91 minutes. N, N'-dihydroxy-N "-
1.3 mass% methanol solution of diethyl melamine 1.3
After 4 minutes, 5-methyl-2-mercaptobenzimidazole was dissolved in a methanol solution of 4.8 × 10 ⁻³ mol per mol of silver and 1-phenyl-2-heptyl-5-mercapto-1, Silver halide emulsion 1 was prepared by adding 3,4-triazole in a methanol solution at 5.4 × 10 ⁻³ mol per mol of silver.

The grains in the prepared silver halide emulsion had an average sphere equivalent diameter of 0.042 μm and a variation coefficient of the sphere equivalent diameter of 20%.
Of silver iodobromide particles uniformly containing 3.5 mol% of iodine. The particle size and the like were determined from the average of 1000 particles using an electron microscope. The {100} plane ratio of the particles was determined to be 80% using the Kubelka-Munk method.

<< Preparation of Silver Halide Emulsion 2 >> In the preparation of the silver halide emulsion 1, the liquid temperature at the time of grain formation was set at 30 ° C.
The temperature was changed to 7 ° C., the solution B was changed to dilute 15.9 g of potassium bromide to a volume of 97.4 ml with distilled water, and the solution D was prepared by diluting 45.8 g of potassium bromide with a volume of 400 m in distilled water.
The silver halide emulsion 2 was prepared in the same manner except that the dilution was changed to 1 and the addition time of the solution C was changed to 30 minutes to remove potassium hexacyanoferrate (II). Precipitation / desalting / washing / dispersion was carried out in the same manner as in silver halide emulsion 1. Further, the addition amount of a methanol solution having a molar ratio of 1: 1 between the spectral sensitizing dye A and the spectral sensitizing dye B is 7.5 × 10 ^-4 mol as the total amount of the sensitizing dye A and the sensitizing dye B per mol of silver. ,
Tellurium sensitizer B was added in an amount of 1.1 × 10
^-4 mol, 1-phenyl-2-heptyl-5-mercapto-1,3,4-triazole was added to 3.3 mol per mol of silver.
Spectral sensitization, chemical sensitization, and 5-methyl-2-mercaptobenzimidazole, 1-phenyl-2-heptyl-5-mercapto-1,3 were carried out in the same manner as in Emulsion 1, except that the amount was changed to × 10 ^-3 mol. And 4-triazole were added to obtain a silver halide emulsion 2. The emulsion grains of the silver halide emulsion 2 were pure silver bromide cubic grains having an average equivalent sphere diameter of 0.080 μm and a coefficient of variation in equivalent sphere diameter of 20%.

<< Preparation of Silver Halide Emulsion 3 >> In the preparation of silver halide emulsion 1, a liquid temperature of 30.degree.
Silver halide emulsion 3 was prepared in the same manner except that the temperature was changed to 7 ° C.
Was prepared. Further, precipitation / desalting / water washing / dispersion was carried out in the same manner as in silver halide emulsion 1. The molar ratio of the spectral sensitizing dye A to the spectral sensitizing dye B is 1: 1 as a solid dispersion (aqueous gelatin solution), and the amount added is 6 × 10 ⁻ Silver halide emulsion 3 was obtained in the same manner as in emulsion 1, except that the amount of ³ moles of tellurium sensitizer B was changed to 5.2 × 10 ^-4 mole per mole of silver.
The emulsion grains of the silver halide emulsion 3 have an average equivalent sphere diameter of 0.0
The silver iodobromide particles uniformly contained 3.5 mol% of iodine having a sphere-equivalent diameter of 34% and a coefficient of variation of 20%.

<< Preparation of Mixed Emulsion A for Coating Solution >> 70% by mass of silver halide emulsion 1, 15% by mass of silver halide emulsion 2 and 15% by mass of silver halide emulsion 3 were dissolved. 7 × 10 ⁻³ mol per mol of silver was added as a 1% by mass aqueous solution of the amide. Further, the content of silver halide per kg of the mixed emulsion for coating solution was 38.2 as silver.
g.

(Preparation of Silver Organic Acid Dispersion) Behenic acid manufactured by Henkel (product name: Edenor C22-85R)
6 kg, 423 L of distilled water, 49.2 L of a 5 mol / L NaOH aqueous solution, and 120 L of tert-butanol were mixed, and the mixture was stirred and reacted at 75 ° C. for 1 hour to obtain a sodium behenate solution. Separately, an aqueous solution 2 of 40.4 kg of silver nitrate
06.2 L (pH 4.0) was prepared and kept at 10 ° C. The reaction vessel containing 635 L of distilled water and 30 L of tert-butanol was kept at 30 ° C., and with sufficient stirring, the total amount of the sodium behenate solution and the total amount of the silver nitrate aqueous solution were respectively 93 minutes and 15 seconds at a constant flow rate. Added over 90 minutes. At this time, only the aqueous silver nitrate solution was added for 11 minutes after the addition of the aqueous silver nitrate solution was started, and then the addition of the sodium behenate solution was started. After the addition of the aqueous silver nitrate solution was completed, only the sodium behenate solution was added for 14 minutes and 15 seconds. I was doing it. At this time, the temperature in the reaction vessel was set at 30 ° C., and the external temperature was controlled so that the liquid temperature became constant. Further, the piping of the addition system of the sodium behenate solution was kept warm by circulating hot water outside the double pipe, and the liquid temperature at the outlet of the tip of the addition nozzle was adjusted to 75 ° C. The piping of the silver nitrate aqueous solution addition system was kept warm by circulating cold water outside the double tube. The addition position of the sodium behenate solution and the addition position of the aqueous silver nitrate solution were arranged symmetrically about the stirring axis, and were adjusted to a height such that they did not come into contact with the reaction solution.

After the completion of the addition of the sodium behenate solution, the mixture was left to stir at the same temperature for 20 minutes, and 35 minutes over 30 minutes.
C., and aging was performed for 210 minutes. Immediately after the completion of aging, the solid content was separated by centrifugal filtration, and the solid content was washed with water until the conductivity of the filtered water became 30 μS / cm. Thus, a silver salt of an organic acid was obtained. The obtained solid content was stored as a wet cake without drying.

When the morphology of the obtained silver behenate particles was evaluated by electron microscopic photographing, a = 0.14 μm on average.
m, b = 0.4 μm, c = 0.6 μm, an average aspect ratio of 5.2, an average equivalent sphere diameter of 0.52 μm, and a flake-like crystal having a sphere equivalent diameter variation coefficient of 15%. (A, b, c are the provisions of the text)

To a wet cake having a dry solid content of 260 kg, polyvinyl alcohol (trade name: PVA-2)
17) Add 19.3 kg and water to make the total amount 1000
kg, and then slurried with a dissolver blade, and then a pipeline mixer (Model Mizuho Kogyo: PM-10)
Was predispersed.

Next, the pre-dispersed undiluted solution was subjected to a dispersing machine (trade name: Microfluidizer M-610, manufactured by Microfluidics International Corporation, using a Z-type interaction chamber) at a pressure of 1
It adjusted to 260 kg / cm ² and processed three times to obtain a silver behenate dispersion. In the cooling operation, a coiled heat exchanger was mounted before and after the interaction chamber, and the dispersion temperature was set to 18 ° C. by adjusting the temperature of the refrigerant.

(Preparation of Reducing Agent Dispersion and Reducing Agent Complex Dispersion) << Preparation of Reducing Agent-1 Dispersion >> Reducing Agent-1 (1,1-bis (2-hydroxy-3,5-dimethylphenyl)- 3,
10 kg of 5,5-trimethylhexane) and modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.)
16 kg of water was added to 10 kg of a 20% by mass aqueous solution of the above, and mixed well to form a slurry. The slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes.
0.2 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the reducing agent to 25% by mass to obtain a reducing agent-1 dispersion. The reducing agent particles contained in the reducing agent dispersion thus obtained had a median diameter of 0.42 μm and a maximum particle diameter of 2.0 μm or less. The obtained reducing agent dispersion was filtered through a polypropylene filter having a pore size of 10.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Reducing Agent-2 Dispersion >> Reducing Agent-2
10 kg of (2,2′-isobutylidene-bis- (4,6-dimethylphenol)) and 20% by mass of modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.)
16 kg of water was added to 10 kg of the aqueous solution and mixed well to form a slurry. This slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes, and then benzoisothiazolinone sodium salt was used. 0.2 g and water were added to adjust the concentration of the reducing agent to 25% by mass to obtain a reducing agent-2 dispersion. The reducing agent particles contained in the reducing agent dispersion thus obtained have a median diameter of 0.38 μm and a maximum particle diameter of 2.0 μm.
m or less. The resulting reducing agent dispersion had a pore size of 10.0.
Filtration was performed with a μm polypropylene filter to remove foreign substances such as dust, and stored.

<< Preparation of Dispersion of Reducing Agent Complex-3 >> Reducing Agent Complex-3 (2,2'-methylenebis- (4-ethyl-6-
10 kg of a 1: 1 complex of tert-butylphenol) and triphenylphosphine oxide, 0.12 kg of triphenylphosphine oxide and 16 kg of a 10% by mass aqueous solution of modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Poval MP203) were added to 7.2 kg of water. Was added and mixed well to form a slurry. The slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 4 hours and 30 minutes, and then benzoisothiazolinone sodium salt was added. 0.2 g and water were added to adjust the concentration of the reducing agent to 25% by mass to obtain a reducing agent complex-3 dispersion. The reducing agent complex particles contained in the thus obtained reducing agent complex dispersion had a median diameter of 0.46 μm and a maximum particle diameter of 1.6 μm or less. The resulting reducing agent complex dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Reducing Agent-4 Dispersion >> Reducing Agent-4
(2,2′-methylenebis- (4-ethyl-6-ter
t-butylphenol)) and 10 kg of modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.)
6 kg of water was added to 20 kg of a 0 mass% aqueous solution and mixed well to form a slurry. This slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes, and then benzoisothiazolinone sodium salt 0.2 g and water were added to adjust the concentration of the reducing agent to 25% by mass.
A dispersion was obtained. The reducing agent particles contained in the reducing agent dispersion thus obtained had a median diameter of 0.40 μm and a maximum particle diameter of 1.5.
μm or less. The resulting reducing agent dispersion had a pore size of 3.0.
Filtration was performed with a μm polypropylene filter to remove foreign substances such as dust, and stored.

<< Preparation of Dispersion of Reducing Agent-5 >> Reducing Agent-5
(2,2′-methylenebis- (4-methyl-6-ter
t-butylphenol)) and 10 kg of modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.)
6 kg of water was added to 20 kg of a 0 mass% aqueous solution and mixed well to form a slurry. This slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes, and then benzoisothiazolinone sodium salt 0.2 g and water were added to adjust the concentration of the reducing agent to 25% by mass.
A dispersion was obtained. The reducing agent particles contained in the reducing agent dispersion thus obtained had a median diameter of 0.38 μm and a maximum particle diameter of
μm or less. The resulting reducing agent dispersion had a pore size of 3.0.
Filtration was performed with a μm polypropylene filter to remove foreign substances such as dust, and stored.

(Preparation of 15% by mass dispersion of development accelerator-1) 2 kg of water was added to 1 kg of development accelerator-1 and 2 kg of a 10% by mass aqueous solution of modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Poval MP203). The mixture was added and mixed well to form a slurry. This slurry was fed by a diaphragm pump, and a horizontal sand mill (UVM-2: IMEX Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm was used.
), And 0.02 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the development accelerator to 15% by mass.
1 was obtained. The development accelerator particles contained in the development accelerator dispersion thus obtained had a median diameter of 0.32 μm and a maximum particle diameter of 1.5 μm or less. The obtained reducing agent dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored. (Preparation of Dispersion of Hydrogen Bonding Compound-1) 10 kg of hydrogen bonding compound-1 (tri (4-t-butylphenyl) phosphine oxide) and 10% by mass of modified polyvinyl alcohol (Poval MP203 manufactured by Kuraray Co., Ltd.) Aqueous solution 2
10 kg of water was added to 0 kg and mixed well to form a slurry. This slurry is fed by a diaphragm pump, and a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm.
After dispersion for 3 hours and 30 minutes, 0.2 g of benzoisothiazolinone sodium salt and water were added to reduce the concentration of the reducing agent to 2
It was adjusted to 2% by mass to obtain a hydrogen bonding compound-2 dispersion. The reducing agent particles contained in the thus obtained reducing agent dispersion had a median diameter of 0.35 μm and a maximum particle diameter of 1.5 μm.
m or less. The obtained hydrogen bonding compound dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

(Preparation of Organic Polyhalogen Compound Dispersion) << Preparation of Organic Polyhalogen Compound-1 Dispersion >> 10 kg of organic polyhalogen compound-1 (2-tribromomethanesulfonylnaphthalene) and modified polyvinyl alcohol (Kuraray Co., Ltd.) 10% of a 20% by weight aqueous solution of Poval MP203), 0.4 kg of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate, and 16 kg of water
Was added and mixed well to form a slurry. This slurry is fed by a diaphragm pump and has an average diameter of 0.5 mm.
Horizontal sand mill filled with zirconia beads (UVM
-2: manufactured by Imex Co., Ltd.) for 5 hours, and then 0.2 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the organic polyhalogen compound to 23.5% by mass. An organic polyhalogen compound-1 dispersion was obtained. The organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained have a median diameter of 0.1.
36 μm, and the maximum particle size was 2.0 μm or less. The obtained organic polyhalogen compound dispersion was filtered through a polypropylene filter having a pore size of 10.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Dispersion of Organic Polyhalogen Compound-2 >> 10 kg of organic polyhalogen compound-2 (tribromomethanesulfonylbenzene) and 20% by mass of modified polyvinyl alcohol (Poval MP203 manufactured by Kuraray Co., Ltd.)
10 kg of an aqueous solution, 0.4 kg of a 20% by mass aqueous solution of sodium triisopropylnaphthalenesulfonate,
4 kg was added and mixed well to form a slurry. The slurry was sent by a diaphragm pump and had an average diameter of 0.1 mm.
After dispersing for 5 hours in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with 5 mm zirconia beads, benzoisothiazolinone sodium salt 0.2
g and water were added to adjust the concentration of the organic polyhalogen compound to 26% by mass.
A dispersion was obtained. The organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained had a median diameter of 0.41 μm and a maximum particle diameter of 2.0 μm or less. The resulting organic polyhalogen compound dispersion has a pore size of 10.0 μm.
Then, the mixture was filtered with a polypropylene filter of m to remove foreign substances such as dust, and stored.

<< Preparation of Dispersion of Organic Polyhalogen Compound-3 >> 10 kg of organic polyhalogen compound-3 (N-butyl-3-tribromomethanesulfonylbenzamide) and modified polyvinyl alcohol (Poval MP manufactured by Kuraray Co., Ltd.)
203), 20 kg of a 10 mass% aqueous solution of sodium triisopropylnaphthalenesulfonate, 0.4 kg of a 20 mass% aqueous solution of sodium triisopropylnaphthalenesulfonate, and 8 kg of water were added and mixed well to form a slurry. This slurry was fed by a diaphragm pump, and a horizontal sand mill (UVM-2: IMEX Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm was used.
After dispersing for 5 hours, 0.2 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the organic polyhalogen compound to 25% by mass. This dispersion was heated at 40 ° C. for 5 hours to obtain an organic polyhalogen compound-3 dispersion. The organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained had a median diameter of 0.36 μm and a maximum particle diameter of 1.5 μm or less.
The resulting organic polyhalogen compound dispersion had a pore size of 3.0 μm.
Then, the mixture was filtered with a polypropylene filter of m to remove foreign substances such as dust, and stored.

(Preparation of Phthalazine Compound-1 Solution) 8k
g modified Kuraray Co., Ltd. modified polyvinyl alcohol MP20
Was dissolved in 174.57 kg of water, and then 3.15 kg of a 20% by mass aqueous solution of sodium triisopropylnaphthalenesulfonate and 14.28 kg of a 70% by mass aqueous solution of phthalazine compound-1 (6-isopropylphthalazine) were added. A 5% by mass solution of compound-1 was prepared.

(Preparation of Mercapto Compound Aqueous Solution) << Preparation of Mercapto Compound-1 Aqueous Solution >> 7 g of mercapto compound-1 (1- (3-sulfophenyl) -5-mercaptotetrazole sodium salt) was dissolved in 993 g of water. A 7% by mass aqueous solution was obtained.

<< Preparation of Mercapto Compound-2 Aqueous Solution >> In the preparation of the above mercapto compound-1 aqueous solution, mercapto compound-1 was changed to mercapto compound-2 (1- (3-methylureidophenyl) -5-mercaptotetrazole). Other than the above, a mercapto compound-
2 was prepared.

(Preparation of Pigment-1 Dispersion) I. Pig
Ment Blue 60 and 64 g of Demol N manufactured by Kao Corporation were added to 250 g of water and mixed well to form a slurry. Prepare 800 g of zirconia beads having an average diameter of 0.5 mm and put in a vessel together with the slurry,
The mixture was dispersed for 25 hours using a disperser (1 / 4G sand grinder mill: manufactured by Imex Co., Ltd.) to obtain a pigment-1 dispersion. The pigment particles contained in the pigment dispersion thus obtained had an average particle size of 0.21 μm.

(Preparation of SBR latex liquid) << Preparation of SBR latex liquid-1 >> SB at Tg = 23 ° C.
An R latex was prepared as follows. Ammonium persulfate was used as a polymerization initiator, an anionic surfactant was used as an emulsifier, styrene was 70.5 mass, butadiene was 26.5.
After emulsion polymerization of 3 mass of acrylic acid and 3 mass of acrylic acid,
For 8 hours. Thereafter, the mixture was cooled to 40 ° C., adjusted to pH 7.0 with aqueous ammonia, and further added with Sandet BL manufactured by Sanyo Chemical Co., Ltd. to a concentration of 0.22%. Next, a 5% aqueous sodium hydroxide solution is added to the mixture to adjust the pH.
The pH was adjusted to 8.3 and further adjusted to pH 8.4 with aqueous ammonia. The Na ⁺ ion used at this time and N
The molar ratio of H ₄ ⁺ ions was 1: 2.3. Further, 0.15 ml of a 7% aqueous solution of sodium salt of benzoisothiazolinenone was added to 1 kg of this liquid to prepare SBR latex liquid-1.

(SBR latex: -St (70.5)
-Bu (26.5) -AA (3)-latex) T
g 23 ° C, average particle size 0.1 µm, concentration 43 mass%, 25 ° C 60% R
Equilibrium water content in H: 0.6% by mass, ionic conductivity: 4.
2 mS / cm [Ion conductivity was measured using a conductivity meter CM-30S manufactured by Toa Denpa Kogyo Co., Ltd., and a latex stock solution (43% by mass) was measured at 25 ° C], and pH was 8.4. SBR latexes having different Tg were prepared by a similar method by appropriately changing the ratio of styrene and butadiene.

<< Preparation of SBR Latex Liquid-2 >> SBR
In the latex liquid-1, SBR was prepared in the same manner except that the molar ratio of Na ⁺ ion to NH ₄ ⁺ ion was 1:10.
Latex liquid-2 was prepared.

(Preparation of Coating Solution for Emulsion Layer (Photosensitive Layer)) << Preparation of Coating Solution-1 for Emulsion Layer (Photosensitive Layer) >> 1000 g of the organic acid silver dispersion obtained above, 125 ml of water, and dispersion of reducing agent-1 113g, reducing agent-2 dispersion 91g, pigment-1 dispersion 27g, organic polyhalogen compound-1 dispersion 82g,
Organic polyhalogen compound-2 dispersion 40 g, phthalazine compound-1 solution 173 g, SBR latex (Tg: 2
(0.5 ° C.), 1082 g of a solution and 9 g of an aqueous solution of mercapto compound-1 were sequentially added.
The emulsion layer coating solution to which 158 g was added and mixed well was directly sent to a coating die and coated.

The viscosity of the above emulsion layer coating solution was measured using a B
40 ° C. (No. 1 rotor, 60
rpm) was 85 [mPa · s].

25 ° C. using an RFS fluid spectrometer manufactured by Rheometrics Far East Co., Ltd.
The shearing rate of the coating solution at 0.1, 1, 10, 10
At 0 and 1000 [1 / sec]
220, 70, 40, and 20 [mPa · s].

<< Preparation of Emulsion Layer (Photosensitive Layer) Coating Solution-2 >>
1000 g of the organic acid silver dispersion obtained above, 104 ml of water,
Pigment-1 dispersion 30 g, organic polyhalogen compound-2 dispersion 21 g, organic polyhalogen compound-3 dispersion 69
g, phthalazine compound-1 solution 173 g, SBR latex (Tg: 23 ° C.) solution 1082 g, reducing agent complex-3 dispersion 258 g, and mercapto compound-1 solution 9 g were sequentially added. The emulsion layer coating solution that had been added and mixed well was directly sent to a coating die and coated.

<< Preparation of Emulsion Layer (Photosensitive Layer) Coating Solution-3 >>
1000 g of the organic acid silver dispersion obtained above, 83 ml of water, 25 mass% dispersion 73 of reducing agent-4, 68 g of 25 mass% dispersion of reducing agent-5, 30 g of 5 mass% dispersion of pigment, organic polyhalogen 21 g of a 26% dispersion of compound-2, 69 g of a 25% dispersion of an organic polyhalogen compound-3, 173 g of a 5% by mass solution of a phthalazine compound, 43 mass% SBR latex (Tg) purified by ultrafiltration (UF) and pH adjusted :
232 ° C.) 1082 g, 25 g% dispersion of hydrogen bonding compound-1 124 g, 10% dispersion 12 of development accelerator-1
g and 9 g of a 0.7% by mass solution of mercapto compound-1 were sequentially added.
Was added and mixed well, and the emulsion layer coating solution was directly sent to a coating die and coated.

(Preparation of Emulsion Surface Intermediate Layer Coating Solution) 772 g of a 10% by mass aqueous solution of polyvinyl alcohol PVA-205 (manufactured by Kuraray Co., Ltd.) and a 20% by mass dispersion of a pigment 5.3.
g, 27.5% by mass of a methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymerization mass ratio of 64/9/20/5/2) latex to aerosol OT (American Siana) 5% aqueous solution of
1, 20 mass% aqueous solution of diammonium phthalate
0.5 ml, water was added to make the total amount 880 g, pH
Was adjusted to 7.5 with NaOH to prepare an intermediate layer coating solution, which was then sent to a coating die at 10 ml / m ² . The viscosity of the coating solution was 40 ° C. using a B-type viscometer (No. 1).
Rotor, 60 rpm) was 21 [mPa · s].

(Preparation of Emulsion Protective Layer Coating Solution) << Preparation of Emulsion Protective Layer First Layer Coating Solution >> 64 g of inert gelatin was dissolved in water, and methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer was dissolved. Coalescence (copolymer mass ratio 64/9/20
/ 5/2) 80 g of latex 27.5% by weight liquid, 23 ml of 10% by weight methanol solution of phthalic acid, 23 ml of 10% by weight aqueous solution of 4-methylphthalic acid, 0.5 mol / L
Concentration of 28 ml of sulfuric acid, 5 ml of a 5% by mass aqueous solution of Aerosol OT (manufactured by American Cyanamid Co.), 0.5 g of phenoxyethanol, and 0.5 g of benzoisothiazolinone.
1 g was added, and water was added to make a total amount of 750 g to make a coating solution, and 18.6 ml of a mixture obtained by mixing 26 ml of 4% by mass chrome alum with a static mixer immediately before coating was used.
/ M ² to the coating die. The viscosity of the coating solution was 40 ° C. using a B-type viscometer (No. 1 rotor, 60
rpm) was 17 [mPa · s].

<< Preparation of Coating Solution for Second Layer of Emulsion Surface Protective Layer >> 80 g of inert gelatin was dissolved in water, and a methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymer weight ratio: 6)
4/9/20/5/2) 27.5% by mass latex liquid 1
3.2 g of a 5% by mass solution of a fluorine-based surfactant (F-1: N-perfluorooctylsulfonyl-N-propylalanine potassium salt) in an amount of 3.2 g, and a fluorine-based surfactant (F-2: polyethylene glycol mono ( N-perfluorooctylsulfonyl-N-propyl-2-aminoethyl) ether [average degree of polymerization of ethylene oxide = 1
5]), 32 ml of a 2% by weight aqueous solution of aerosol OT
(American Cyanamid Co.) 5% by mass solution
ml, fine particles of polymethyl methacrylate (average particle size of 0.
7 μm) 4 g, polymethyl methacrylate fine particles (average particle size 4.5 μm) 21 g, 4-methylphthalic acid 1.6
g, phthalic acid 4.8 g, sulfuric acid 44 having a concentration of 0.5 mol / L
ml, benzoisothiazolinone 10mg, total amount 650g
445m of an aqueous solution containing 4% by mass of chromium alum and 0.67% by mass of phthalic acid
1 was mixed with a static mixer immediately before coating as a coating solution for the surface protective layer, and the solution was fed to a coating die at 8.3 ml / m ² . The viscosity of the coating solution was 9 mPa with a B-type viscometer at 40 ° C. (No. 1 rotor, 60 rpm).
.S].

(Preparation of Photothermographic Material) << Preparation of Photothermographic Material-1 >> On the back surface side of the undercoating support, an antihalation layer coating solution was coated at a solid content of 0.04 g / solid fine particle dye. m ^2, and the coating amount of the gelatin for the back surface protective layer was 1.7 g / m 2.
Coating was applied simultaneously to form ² and dried to form a back layer.

On the surface opposite to the back surface, the emulsion layer, the intermediate layer, the first protective layer, and the second protective layer were simultaneously coated in order from the undercoat surface by a slide bead coating method, and the photothermographic material-1 Was prepared. At this time, the emulsion layer and the intermediate layer
The temperature of the first protective layer was adjusted to 36 ° C, and the temperature of the first protective layer was adjusted to 37 ° C. Coating amount of each compound in emulsion layer (g / m ² )
Is as follows.

Silver behenate 6.19 Reducing agent-1 0.67 Reducing agent-2 0.54 Pigment (CI Pigment Blue 60) 0.032 Polyhalogen compound-1 0.46 Polyhalogen compound-20 .25 phthalazine compound-1 0.21 SBR latex solution-1 11.1 mercapto compound-1 0.002 silver halide (as Ag) 0.145

The conditions for coating and drying are as follows. The coating is performed at a speed of 160 m / min, and the gap between the tip of the coating die and the support is set to 0.10 to 0.30 mm.
The pressure in the decompression chamber was set 196 to 882 Pa lower than the atmospheric pressure. The support was neutralized with ion wind before coating. In the subsequent chilling zone, the coating solution is cooled by air having a dry-bulb temperature of 10 to 20 ° C., and is transferred in a non-contact type. It was dried with a dry air having a wet bulb temperature of 15 to 21 ° C. After drying, 25
After adjusting the humidity at 40 to 60% RH at 70 ° C,
Heated to 90 ° C. After heating, the film surface was cooled to 25 ° C.

The resulting photothermographic material had a matte degree of Beck smoothness of 550 seconds on the photosensitive layer side and 13 minutes on the back side.
It was 0 seconds. Further, the pH of the film surface on the side of the photosensitive layer was measured and found to be 6.0.

<< Samples 001 to 004 >> A reducing agent and a mercapto compound-1 shown in Table 1 were added to the emulsion layer (photosensitive layer) coating solution-1.
1, and the compound represented by the general formula (A) was added in the type and amount shown in Table 1. Others were the same as in the preparation of the photothermographic material-1, and the sample 001 was prepared.
To 004 were produced. The ratio of sodium ion to ammonium ion in the SBR latex solution-1 was 1: 2.3 as in the case of the emulsion layer (photosensitive layer) coating solution-1. However, for Samples 003 and 004 using the reducing agent of the present invention, the application amount of the reducing agent was changed to 65% so that the image density became almost equal to that of Sample 001. The development accelerator, which is a compound of the general formula (A), was added as a 15% solid dispersion in an amount of 3 mol% based on the reducing agent.

<< Preparation of Photothermographic Material-2 >> The above-mentioned photothermographic material-1 was changed from the emulsion layer coating solution-1 to the emulsion layer coating solution-2. A photothermographic material-2 was prepared in the same manner as the photothermographic material-1 except for the above. The coating amount (g / m ² ) of each compound in the emulsion layer at this time is as follows.

Silver behenate 6.19 Pigment (CI Pigment Blue 60) 0.036 Polyhalogen compound-2 0.13 Polyhalogen compound-3 0.41 Phthalazine compound-1 0.21 SBR latex liquid-1 11.1 Reducing agent complex-3 1.54 Mercapto compound-1 0.002 Silver halide (as Ag) 0.10

<< Preparation of Samples 005 to 010 >> The emulsion layer (photosensitive layer) coating solution-2 was mixed with a mercapto compound-
1 was changed to the amount of the mercapto compound-1 shown in Table 1, and the reducing agent, the compound represented by the general formula (A), and the compound represented by the general formula (A) were changed to the types shown in Table 1. And amount. Otherwise, samples 005 to 010 were prepared in the same manner as in the preparation of the photothermographic material-2. Note that S
The ratio of sodium ion to ammonium ion in BR latex solution-1 was the same as in emulsion layer (photosensitive layer) coating solution-2.
1: 2.3. At this time, the reducing agent complex was replaced by an equimolar amount, and the compound represented by the general formula (A) was added as a 15% solid dispersion in an amount of 3 mol% based on the reducing agent. Also,
The compound represented by the general formula (B) was added as a 20% solid dispersion in an amount of 1 mol% based on the reducing agent.

<< Preparation of Photothermographic Material-3 >> The above-mentioned photothermographic material-1 was changed from the emulsion layer coating solution-1 to the emulsion layer coating solution-3. Was removed. Further, the fluorine-based surfactants F-1, F-2, and F-3 of the second protective layer and the back surface protective layer.
And F-4, each having the same mass of F-5, F-6, and F-7
And F-8. Otherwise, the photothermographic material-3 was prepared in the same manner as the photothermographic material-1. The coating amount (g / m ² ) of each compound in the emulsion layer at this time is as follows.

Silver behenate 5.57 Pigment (CI Pigment Blue 60) 0.032 Reducing agent-4 0.40 Reducing agent-5 0.36 Polyhalogen compound-2 0.12 Polyhalogen compound-30 .37 phthalazine compound-1 0.19 SBR latex solution-1 10.0 hydrogen bonding compound-1 0.59 development accelerator-1 0.028 mercapto compound-1 0.002 silver halide (as Ag) 09

<< Preparation of Samples 011 to 020 >> A reducing agent, a mercapto compound-1, and a hydrogen bonding compound-1 were reduced in the emulsion layer (photosensitive layer) coating solution-3 as shown in Table 1. The compounds represented by the general formula (A) and the compound represented by the general formula (B) were changed to the types and amounts of the agent, the mercapto compound-1, and the hydrogen bonding compound-1, and the types shown in Table 1 were used. And amount. Otherwise, Samples 011 to 020 were produced in the same manner as in the production of the photothermographic material-3. The ratio of sodium ion to ammonium ion in the SBR latex liquid-1 was 1: 2.3 as in the case of the emulsion layer (photosensitive layer) coating liquid-3.

The chemical structures of the compounds used in the examples of the present invention are shown below.

[0253]

Embedded image

[0254]

Embedded image

[0255]

Embedded image

[0256]

Embedded image

[0257]

Embedded image

(Evaluation of photographic performance) The photosensitive material prepared as described above was processed and cut into half-cut sizes, and then subjected to 25 ° C RH.
Aged at 40% for 7 days. After that, Fuji Medical Dry Laser Imager FM-DP L (up to 60m
Exposure and thermal development of photographic material with W (IIIB) output 660 nm semiconductor laser (112 ° C-119 ° C-12
001 with four panel heaters set at 1 ° C-121 ° C
010 and 015 to 020 are 24 seconds in total, 011 to 0
14 for a total of 14 seconds), and the obtained image was evaluated using a densitometer. From this, the sensitivity of each photosensitive material was determined. The sensitivity was a relative sensitivity to the sample 001 and was represented by a ΔLogE value. In addition, a chest radiograph was printed and the silver tone was visually evaluated. The evaluation results were ranked as follows. ◎ The preferred silver tone is very close to the wet treatment system ○ The preferred silver tone is almost the same as the wet treatment system △ There is a slight difference from the wet treatment system but within the allowable range × The color tone is clearly different from the wet treatment system Unacceptable results are shown in Table 1.

[0259]

[Table 1]

From the examples of samples 001 to 004 in Table 1,
By combining the reducing agent (R1) of the present invention with a development accelerator, a photothermographic material having high sensitivity and excellent silver tone can be produced. Further, from the examples of Samples 005 to 010, the same effect can be obtained when a reducing agent complex is used, and the color tone can be further improved by using the compound represented by the general formula (B) in combination. it can. Further, from the examples of Samples 011 to 014, it is preferable to use the reducing agent (R1) of the present invention and the compound represented by the general formula (B) in a rapid processing system of 14 seconds, so that the photothermographic development of silver tone is preferable. Material can be made. Further, samples 015 to 02
0, the reducing agent (R1) of the present invention, the development accelerator, the compound represented by the general formula (D),
A photothermographic material having a particularly preferable silver tone and sensitivity can be prepared by using the compound represented by the formula (1) in combination.

The reducing agent of the present invention forms an image by silver development and, at the same time, changes the color tone of the light-sensitive material with a yellow dye formed from its own oxidized product. The color tone of the photothermographic material can be freely adjusted by using the agent and the reducing agent of the general formula (R2) outside the present invention in combination and changing the usage ratio. The pigment formation is higher on the higher density side, and the medium to high density range can be adjusted. on the other hand,
The compound represented by the general formula (B) has a feature of forming a yellow pigment in a low concentration range, and by using these in combination, it is possible to further finely adjust the color tone. Also,
It is effective to adjust the amount of ammonium ion and sodium ion in the photothermographic material to adjust the cyan taste.
By combining this, it became possible to further finely adjust the color tone.

(Example 2) Mercapto compound-2 (1- (3) was added to the emulsion layer coating solution of each photothermographic material of Example 1.
-Methylureidophenyl) -5-mercaptotetrazole) to a concentration of 0.1 g / m ² ,
The ratio of sodium ion to ammonium ion in latex liquid-1 was changed to 1:10 (SBR latex liquid-2). Others are the same as in the first embodiment.
1 to 120 were produced. These were also evaluated in the same manner as in Example 1. Also in this case, the same result as in Example 1 was obtained. It was confirmed that color tone can be controlled by using the compounds of the present invention in combination. In the combination of this embodiment, the cyan density was improved, and the color tone in the high density range was further improved. Further, it was confirmed that the sensitivity and fog of the raw material after aging were small, and that the material was good in preservability.

[0263]

According to the present invention, it is possible to provide a photothermographic material which can form an image in a short time, and is excellent in silver tone of the image and stability of the processed image with time.

Claims (5)

[Claims] 1. A photothermographic material comprising at least one photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent for silver ions and a binder on one surface of a support, The photothermographic method, wherein the reducing agent is a compound represented by the following general formula (R1), and contains at least one compound represented by the following general formula (A) and having no high contrast effect. material. Embedded image In the formula (R1), R ¹¹ and R ^{11 ′} each independently represent a tertiary alkyl group having 4 to 20 carbon atoms. R ¹²
And R ^{12 ′} each independently represent a hydrogen atom, a phenyl group, an alkoxy group, an aryloxy group, an acyloxy group, an alkylthio group or an arylthio group. R ¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. General formula (A) Q ¹ -NHNHCONH-R ^{1 In the} general formula (A), Q ¹ represents an aryl group or a heterocyclic group. R ¹ represents an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group or a heterocyclic group. 2. The compound represented by the general formula (A) having no toning effect, wherein Q ¹ is an aryl group substituted with an electron-withdrawing group, or a substituted or unsubstituted heterocyclic group. 2. The photothermographic material according to item 1. 3. The substituted or unsubstituted heterocyclic group is
3. The photothermographic material according to claim 2, which is a monocyclic or condensed-ring heterocyclic group. 4. The photothermographic material according to claim 1, comprising at least one compound represented by the following general formula (B). General formula (B) In the general formula (B), R ¹ represents a tertiary alkyl group. R ² represents an alkyl group, an alkoxy group, or a halogen atom. R ³ represents a hydrogen atom, an aryl group, a hydroxy group, an alkoxy group, an aryloxy group, or an amino group. 5. The photothermographic material according to claim 1, comprising a compound represented by the following general formula (D). Embedded image In the general formula (D), R ²¹ , R ²² , and R ²³ are
Each independently represents a substituted or unsubstituted alkyl group, aryl group, alkoxy group, aryloxy group, amino group, or heterocyclic group. When R ²¹ , R ²² , and R ²³ have a substituent, the substituent is a halogen atom, an alkyl group, an aryl group, an alkoxy group, an amino group, an acyl group, an acylamino group, an alkylthio group, an arylthio group, a sulfonamide group. , An acyloxy group, an oxycarbonyl group, a carbamoyl group, a sulfamoyl group, a sulfonyl group, or a phosphoryl group.