JPS61269147A - Heat developable photographic element - Google Patents

Abstract

PURPOSE:To prevent uneven image density due to scattering of heating temp. by incorporating a base or a base precursor and a photographic reagent to be allowed to release a specified compound by the action of the base. CONSTITUTION:The heat-developable photographic element contains at least the base or its precursor and the photographic reagent to be allowed by the action of the base to release the compound represented by the formula: R deg.-SH in which R deg. is optionally substd. alkyl, cycloalkyl, aralkyl, alkenyl, or aryl. This reagent is not decomposed by the action of base until an amt. of base to be increased from the middle stage to the final stage of the development, and the compd. of the formula having development inhibition action stops the development, thus permitting uneven image density due to scattering of heating temp. to be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Background Technical Field of the Invention The present invention relates to a heat-developable photographic element, and more particularly to a heat-developable photographic element whose photographic properties are stable even when processing conditions vary.

PRIOR ART AND THEIR PROBLEMS Photography using silver halide has a higher sensitivity, mj! It has been used most widely since it has excellent photographic characteristics such as knots. In recent years, the image forming method for photosensitive materials using silver halide has been changed from the conventional wet processing using a developer at room temperature to a thermal development process that does not use a developer, making it possible to easily and quickly create images. Techniques have been developed to enable this.

Heat-developable photosensitive materials are well known in the art, and information on heat-developable photosensitive materials and their processes is well known in the art.

For example, pages 553-555 of Fundamentals of Photographic Engineering (published by Corona Publishing, 1979), Image Information 40, published in April 1978.
Page, Neblett's/Pack of Photography and Reprogramming 7 4 (Neblett
s)Iandbook of Photographer
aphyandreprography) 7th edition (7
thEd, ) 7y7 Nostrand Reinhold Company (Van Na5trand Re1nhol
d Company), pages 32-33, U.S. Patent No. 3,
No. 152,904, No. 3,301,678, No. 3
, No. 392, No. 020, No. 3,457,075,
British Patent No. 1.131.108, British Patent No. 1,167.7
No. 77 and Research Disclosure Magazine, June 1978 issue, pages 9-15 (RD-17029).

For information on how to obtain color images through heat development,
Many methods have been proposed. A method for forming a color image by combining an oxidized developer with a coupler is described in U.S. Pat.
Phenyl diamine reducing agents and phenolic or active methylene couplers are used in U.S. Pat. No. 3,761,270; On page 32, sulfonamide phenolic reducing agents are also described in U.S. Pat.
In No. 240, a sulfonamide phenol reducing agent and 4
Combinations with equivalent couplers have been proposed.

Regarding the method of forming positive color images by photosensitive silver dye bleaching method, for example, see Research Disclosure Magazine, April 1976 issue, pages 30-32 (RD-144
33), December 1976 issue of the same magazine, pages 14-15 (R
D-15227), U.S. Pat. No. 4,235,957, and others describe useful dyes and bleaching methods.

Furthermore, an image forming method by thermal development using a compound that has a dye moiety in advance and can release a mobile dye in response to or inversely to the reduction reaction of silver halide to silver at high temperatures has been patented in a European patent. Publication No. 76.492, same #79.0
No. 58, JP-A-58-28928, JP-A No. 58-260
It is disclosed in No. 08.

In many cases, such heat-developable photosensitive materials are developed by applying heat using a base as a development accelerator, but once the photosensitive material reaches a high temperature, it takes time to cool down.

Development progresses too much, image quality deteriorates, and even if the heating pattern is the same, development progress may vary due to subtle changes in conditions such as external temperature, heating temperature, water content of the photosensitive material, and time. . Furthermore, when the dye produced or released in the photosensitive element is thermally transferred to the image-receiving element, the heating for this transfer causes extra development;
A problem may also occur in which fog in the transferred image increases.

Similar techniques for avoiding such development, such as the diffusion transfer method, are described in Research Disclosure, Vol. 123, p. 22, Vol. 180, p. 18030, British Patent No. 2,082°787A, etc. A method using an acid polymer for neutralization has been proposed, but when applied to a heat-developable photosensitive material, the resulting image density decreases because the base is quickly neutralized. In addition, as a compound that releases an acid when heated, for example, JP-A-49-1
No. 58842, Japanese Unexamined Patent Application Publication No. 50-57452, etc.
An acidic component that dissolves at 60°C or higher or releases a volatile acid is described, but when the compound proposed here is applied to a heat-developable photosensitive material, it is difficult to convert it into a base before heating to start development. , the development is inhibited and the resulting image density is reduced.

■ Purpose of the invention The purpose of the present invention is to
It is an object of the present invention to provide a heat-developable photographic element in which development can be stopped at an appropriate time and unevenness in image density due to variations in heating temperature can be prevented.

■Disclosure of invention Such objects are achieved by the invention described below.

That is, one aspect of the present invention is a heat-developable photographic element characterized by containing at least a base or a base precursor, and a photographic reagent capable of releasing a compound represented by the following general formula (I) by the action of the base.

General formula (I) R'-3H (In the above general formula (I), Ro represents a substituted or unsubstituted alkyl group, cycloalkyl group, aralkyl group, alkenyl group, or aryl group.) ■ Specific structure of the invention Hereinafter, a specific configuration of the present invention will be explained in detail.

The heat-developable photographic element of the present invention contains a photographic reagent capable of releasing a compound represented by the following general formula (I) by the action of a base, that is, a development inhibitor precursor.

General Formula %Formula % (I) In the above general formula (I), Ro represents a substituted or unsubstituted alkyl group, cycloalkyl group, aralkyl group, alkenyl group or aryl group.

Examples of substituents in this case include alkyl groups, aryl groups, cycloalkyl groups, aralkyl groups, alkoxy groups,
Aryloxy group, alkylthio group, arylthio group,
Acyl group, alkoxycarbonyl group, amine group, N-substituted amino group, acylamino group, carbamoyl group, N-5
ilcarbamoyl group, alkylsulfonyl group.

Arylsulfonyl group, alkylsulfonylamino group,
Aryl/sulfonylamino group, sulfamoyl group, N
-Ji [includes sulfamoyl group, cyano group, nitro group, halogen atom, etc.

Among these, preferred substituents are alkyl groups.

They are an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an acylamino group, a sulfonylamino group, and a halogen atom.

Among the compounds represented by the above general formula (I), those represented by the following general formula (n) are preferred.

General formula In the above general formula (■), n represents an integer of 1 to 5, Z represents the substituent listed for Ro, provided that n is 2
In the above cases, Z may be the same or different.

Note that the compound represented by the above general formula (I) has a bad odor when it has a low molecular weight, and the more hydrophobic Ro is, the greater the capri-preventing effect is. It is appropriate that the number of carbon atoms including the group is 6 or more, more preferably 10 to 30.

Preferred examples of the compound represented by the general formula (I) include those having 10 or more carbon atoms among the compounds described in JP-A-59-111636; Compounds are also effective.

1) (+1) Cl8H375H 2) (n) Cl2H2505H 3) (n) Cs Hf70+5H 4) (n) Cl0H210+5H 5) (n) Cl2HsO+5H 8) (n) C14H210+SH ? ) (n) C15H330+5H 8) (n) C+5H3100SH 11) oCH203H 12) (n) Cl2H25SO2NHi>SH, 1
3) (II) C12H25:jj'NHO3H14)
(n) CIGH33ANHKΣ5H15) ζΣ0
OSH In conventional conventional photographic materials, a technique is already known in which a photographically useful group such as a compound represented by formula (I) is protected (blocked) and the compound is released during development.

For example, those using blocking groups such as acyl groups and sulfonyl groups described in Japanese Patent Publication No. 47-44805; A method using a blocking group that releases a photographic reagent through the so-called reverse Michael reaction described in Japanese Patent Publication No. 54-39727, Japanese Patent Application Laid-open No. 57-13
No. 5944, No. 57-135945, and No. 57-136640, which utilize a blocking group that releases a photographic reagent with the production of quinone methide or a quinone methide-like compound through intramolecular electron transfer, JP-A-55 5jij or 6 described in JP-A-57-78541, JP-A-57-135949, and JP-A-57-179842, which utilizes the intramolecular ring-closing reaction described in JP-A-53330.
Techniques that utilize ring cleavage of members are known as well-known techniques.

However, all of these known techniques utilize hydrolysis or deprotonation due to the action of OH- during wet development at around room temperature, and there is no knowledge of heat development using an organic base.

Furthermore, when a photographic reagent in which a photographically useful group is blocked, such as the compound represented by the general formula (I), is used in a conventional photographic light-sensitive material, development is carried out under conditions of pH 11 or higher from the beginning, so the action of OH-'' General formula (
Release of the compound I) from the early stage of development is unavoidable, which often results in a decrease in the achieved density and sensitivity.

Further, it is described in JP-A-59-111836 that the hydrophobic thiols represented by the general formula (I) have a remarkable antifogging effect in photothermographic materials. However, if a compound represented by formula (I), for example, is added to the emulsion layer from the beginning, development may be inhibited from the initial stage, resulting in lower image density and lower sensitivity.

This time, the present inventors have demonstrated that when a reagent blocking the photographically useful groups of the compound represented by general formula (I) is used in a heat-developable photographic element, especially when a base precursor is used, the base released from the reagent blocks these groups. The reagent can release the compound of general formula (I), and the base precursor decomposes to generate a base, which initiates development, but the photographic reagent of the present invention increases the amount of base generated. It decomposes under the action of a base only in the middle to late stages of development, releasing the compound of general formula (I) that has a development inhibitory function, and stopping development (that is, the development inhibitor is released at a certain timing after the start of development). The inventors have discovered that, as a result, it is possible to obtain an image with a high S/N ratio without reducing the final density.

The heat-developable photographic element of the present invention also has the effect of compensating for development temperature unevenness. Heat-developable photographic elements usually have 100
Since development is carried out at a high temperature of .degree. C. or higher, slight variations in temperature on the surface of the photosensitive element are unavoidable, which causes uneven image density. That is, in higher temperature areas, development progresses faster and image density is higher, whereas in lower temperature areas, development progresses more slowly and image density becomes lower. However, in the heat-developable photographic element of the present invention, in higher temperature areas, The release of the compound of general formula (I) from the photographic reagent is also rapid and the image density reaches only a certain point, and the opposite phenomenon occurs in lower temperature areas, so overall there is a compensation effect for temperature unevenness. It is now possible to have

In an image forming method using thermal development, which utilizes a compound that has a dye moiety in advance and releases a mobile (diffusible) dye in response to the reduction reaction of silver halide to silver at high temperatures, the development temperature is Since there is a marked tendency for temperature unevenness to increase as the temperature increases, it is particularly advantageous to use a photographic reagent that releases a base or its precursor and a compound of general formula (I).

As the development inhibitor precursor of the present invention.

The above-mentioned precursors for photographic useful reagents in the conventional photographic system are directly applicable.

Among them, the following three types are preferable.

(Type I) A compound represented by the general formula (I) (hereinafter referred to as A A precursor compound that releases

The form of release of A following base attack on the carbon atoms of these functional groups is the release by cleavage of bonds directly bonded to these carbons: by cleavage of other bonds with electron transfer. Release: Release by cleavage of other bonds by intramolecular nucleophilic attack with or without electron transfer: Release consisting of multiple reaction types as described above: Additionally, release via timing groups. etc.

(Type 2) A precursor compound that releases A through deprotonation by a base or a base released from a base precursor and the subsequent reaction. The reaction format of A release in such a precursor compound is described in (Type 1) above. It is the same as that.

(Type 3) A precursor compound that also has one and releases A by attack of a base on the sulfur or phosphorus atom of these functional groups and subsequent reaction.

The reaction type for releasing A in such a precursor compound is the same as described above (type 1). However, direct electron transfer type on sulfur atom or phosphorus atom is not included.

Specifically, examples of precursor compounds belonging to (Type 1) include JP-B No. 48-9968, JP-A No. 52-8
No. 828, No. 57-82834, U.S. Patent No. 3.31
Sulfur-releasable antifoggants and development inhibitor precursors described in Japanese Patent Publication No. 1,474 and No. 3,615,617, etc.: Japanese Patent Publication No. 54-39727, U.S. Patent No. 3.874
, No. 478, No. 3,932゜480, No. 3,99
No. 3,661, JP-A No. 58-1140, 5g-20
Precursor that releases A by cleavage of acetyl group and subsequent electron transfer or further decarboxylation as described in Japanese Patent Publication No. 59-225168, etc.: Japanese Patent Publication No. 57
-22099, U.S. Patent No. 4'199.354, JP-A-55-53330, etc. Precursor that releases A by ring cleavage and subsequent intramolecular ring-closing reaction: JP-A-55-53330 Precursor that releases A by hydrolysis and subsequent intramolecular ring-closing reaction described in the specification: JP-A-57-76541, JP-A-57-135
No. 945, 57-! No. 179842, same 5
No. 9-3434, No. 59-137945, No. 59-1
Ring cleavage and subsequent electron transfer as described in No. 40445 etc.
and a precursor that releases A upon decarboxylation: Research Disclosure Magazine 15,162 (I976), JP-A-56-77842, U.S. Patent No. 4,307,
Examples include precursors that release A by nucleophilic attack of a base on a carbon-carbon double bond and subsequent elimination, as described in No. 175 and the like.

Specific examples of precursor compounds belonging to (Type 2) include 1, for example, Japanese Patent Publication No. 55-34927, U.S. Pat.
No. 9,029, Special Publication No. 55-9696, No. 55-17
No. 369, JP-A-59-105640, JP-A No. 59-10
Precursors that release A using the so-called reverse Michael reaction described in Japanese Patent Publications No. 54-39727, Japanese Patent Application Laid-open No. 57-13594, etc.
No. 4, No. 57-135945, No. 57-136640
No. 58-976.

-OH dissociates to generate an anion, and A is released as a quinone methide-like compound is generated by intramolecular electron transfer: a precursor of benzisoxazole to O-cyanophenol described in JP-A No. 59-202459. M
Examples include a method using JI.

Examples of precursor compounds belonging to (Type 3) include the sulfonyl group-containing precursor compounds described in JP-A-52-8828.

Furthermore, in these precursors, when A is released during intramolecular electron transfer or intramolecular nucleophilic attack, an appropriate timing group can be used. Typical examples include the decarboxylation reaction described in the above-mentioned specification and the deformylation reaction described in JP-A-59-93442.

Typical development inhibitor precursors are illustrated below.

(Type I) At -A-R (where, Represents -C- or 100H2-, n represents 0 or 1, ) ♂ (Type 2) Mouth 2 -302 Represents R, n represents 0 or l, ) Ha (Type 3) Millet A Zero-3O2R1 Examples of development inhibitor precursors other than those mentioned above include the following.

R3R3 (However, either one of R3 represents a defined group other than a hydrogen atom) (However, z=o, s) A-rich -CH20-R3 Specific examples are given, but the invention is not limited to these. ).

(34) (n) Cl2H75C>5CH2CH
2CN The amount of the development inhibitor precursor used in the present invention varies depending on the compound and the system used, but
The weight of the coating film is generally 50% by weight or less, preferably 30% by weight or less.

:: Also, the development inhibitor precursor 12 of the present invention. -e
j, 2! l! Yo□7. □、A6. "Furthermore, it is also possible to use a development stopper or development stop technique other than the present invention. Such development stop agents and development stop techniques are described in Japanese Patent Application No. 58-216928 and No. 59-48305. The heat content of the aldoxime ester
il,, method of using the solution・Patent application 1985-85834
The method using Rossen rearrangement, which is described in No. 1, and the method using a carboxylic acid ester, which is described in Japanese Patent Application No. 85836/1987, are known.

Examples of synthesis of development inhibitor precursors are described below.

P-hexadecyl dithiophenol 10.5g
(0.03 mol), triethylamine 4. Et 111
(0,033 mol) in methylene chloride solution (80al
1) was cooled and stirred to below 5°C, and 4.2 g (0.03 mol) of benzoyl chloride was added dropwise while maintaining this temperature. After stirring at room temperature for 30 minutes, the reaction solution was concentrated to about half its volume, 150 all of methanol was added, and the precipitated crystals were collected by filtration.

The crude crystals were recrystallized from a mixed solvent of isopropyl alcohol and n-hexane (V = 4/I) to obtain the title compound 9-
7 g (0,021 mol) were obtained. Melting point 68-6
9°C A solution of 43.2 g (0.4 mol) of p-cresol and 58.8 d (0.42 mol) of triethylamine in acetonitrile was cooled to below 10°C, and while maintaining this temperature, p-chlorobenzoyl chloride 73 .5g (0,
42 mol) was added dropwise. After completion of the reaction, the temperature was returned to room temperature and the mixture was stirred for 1 hour, and then the reaction solution was added to 2 portions of water. The precipitated crystals were collected by filtration, washed with water, and then recrystallized with methanol to obtain 88.6 g (0.38 mol) of the title compound.

Contains 84 g (0.34 mol) of p-chlorobenzoic acid p-cresol ester obtained in the above reaction, 50 g (0.28 mol) of N-promosuccinimide, and a trace amount of benzoyl peroxide as a radical initiator. 800 d of carbon tetrachloride solution was refluxed for 1 hour while being irradiated with light. After completion of the reaction, the precipitated succinimide crystals were filtered while hot, and the mother liquor was concentrated under reduced pressure. The residual solution was dissolved in ethyl acetate, washed with water, separated, and the ethyl acetate layer was dried over sodium sulfate. Ethyl acetate was concentrated under reduced pressure, and the remaining liquid was
-Mixed solvent of hexane and ethyl acetate (Manomer 2/1
) to obtain 83.2 g (0,194 mol) of the title compound.

2-Butyloxy-5-(I,1,3,3-tetramethylbutyl)thiophenol 8.2 g (0,028 mol)
, sodium methylate 28% methanol solution 5.4
methanol solution (I00
In d), 10 g (0,031 mol) of the above pro-superior body
was added little by little at room temperature. After the completion of the reaction, the reaction mixture was stirred under reflux for an additional 30 minutes, and then the reaction mixture was poured into water, and the precipitate was extracted with n-hexane. The organic layer was concentrated under reduced pressure, and the residue was purified by flash column chromatography (silica gel, n-hexane/chloroform = 20/1) to obtain 8.5 g (0,018 mol) of the title compound. Melting point 6 low 67°C 3-methylindazole 284g (2 mol), acetonitrile 21. N,N-dimethylacetamide 500Il
A solution of 151 was stirred under reflux, and 3.5
-440 g (2.1 mol) of dichlorobenzoyl chloride
was dripped.

Crystals precipitated during the dropwise addition. After the reflux was continued for another 1 hour, the mixture was cooled to 15°C, and the precipitated crystals were collected by filtration and washed with acetonitrile to give 552.8 g of the title compound (
I, 81 mol) was obtained.

552.8 g (I, 81 mol) of the above 3-methyl compound.

Three portions of a carbon tetrachloride solution containing 320 g (I, 8 mol) of N-bromosuccinimide and 2 g of benzoyl peroxide were refluxed and stirred for 4 hours while being irradiated with light. After completion of the reaction, the precipitated succinimide crystals were filtered off while hot, and the filtrate was concentrated under reduced pressure to about half its volume. The residue was recrystallized by adding 11 ethyl acetate and 100111 chloroform to obtain the title compound 337.
．． 5 g was obtained. The obtained crystals were analyzed by thin layer chromatography and NMR spectra to reveal that the title compound and the 3-
It was found that it was a mixture of methyl compounds, and the content of the title compound was about 89% (molar ratio).

28.1g of the above bromomethyl compound (0.05 after content correction)
5 mol), P-F decyloxythiophenol 1.7 g
(0.5 mol) of 7.3 d (0.052 mol) of triethylamine was added dropwise to the refluxed and stirred solution of 7.3 d (0.052 mol) of triethylamine. After the reaction was completed, the reaction was continued for another 2 hours.
- 100 d of hexane was added and cooled on ice. The precipitate was drawn, and methanol 200d and chloroform 501II
It was recrystallized from a mixed solvent of The crystals obtained here were further recrystallized from a mixed solvent of 150+d acetone and 1oad chloroform to obtain 14.3g (0.02g) of the title compound.
34 mol)° was obtained. Melting point: 78.5 DEG -80 DEG C. The heat-developable photographic element of the present invention contains a base or base precursor.

j Examples of preferred bases include inorganic bases such as alkali metal or alkaline earth metal hydroxides, secondary or tertiary phosphates, borates, carbonates, quinolates, metaborates; ammonium water; Oxides: hydroxides of quaternary alkylammonium; hydroxides of other metals, etc., and organic bases include aliphatic amines (
trialkylamines, hydroxylamines, aliphatic polyamines); aromatic amines (N-alkyl-substituted aromatic amines, N-hydroxylalkyl-substituted aromatic amines and bis(p-(dialkylamino)phenylcomethane) ), heterocyclic amines, amidines, cyclic amidines, guanidines, and cyclic guanidines, and those having a pKa of 8 or more are particularly preferred.

Base precursors include salts of organic acids and bases that are decarboxylated and decomposed by heating, intramolecular nucleophilic substitution reactions, Rossen rearrangement,
Compounds that decompose and release amines through reactions such as Beckmann rearrangement.

Preferably used is one that causes some kind of reaction upon heating and releases a base. Preferred base precursors include trichloroacetic acid salts described in British Patent Nos. 998 and 949, α-sulfonylacetic acid salts described in U.S. Pat. No. 4,060,420, and JP-A-59-180549.
Salts of propiolic acids described in US Patent No. 4゜08
8.498, a salt with a thermally decomposable acid using an alkali metal or alkaline earth metal in addition to an organic base as the base component (JP-A-59-1
95237), patent application using Rossen rearrangement 1982-
Hydroxamic carbamates described in Japanese Patent Application No. 31614/1987, which produce nitriles upon heating, and the like are mentioned. In addition, British Patent No. 998.945, U.S. Patent No. 3,220.846, Japanese Unexamined Patent Publication No. 50-22625, British Patent No. 2,079,480, and Japanese Patent Application No. 1983-1557.
No. 66, No. 59-172956, No. 59-17316
No. 1, No. 59-173889, No. 59-176396
No. 59-176397, No. 59-176398, No. 59-176399, No. 59-176400,
The base precursors described in 59-176401, 59-176402, 59-176998, and 59-176999 are also useful.

Specific examples of base precursors particularly useful in the present invention are shown below.

Guanidine trichloroacetate, methylguanidine trichloroacetate, potassium trichloroacetate, guanidine phenylsulfonylacetate, p-chlorophenylsulfonylacetate guanidine, p-methanesulfonylphenylsulfonylacetate guanidine, potassium phenylpropiolate, phenylpropiol cesium, phenylpropiolate guanidine, p -Guanidine chlorophenylpropiolate, guanidine 2,4-dichlorophenylpropiolate, diguanidine p-phenylene-bis-propiolate, tetramethylammonium phenylsulfonylacetate, tetramethylammonium phenylpropiolate.

The above bases or base precursors can be used in a wide range of ways. A useful range is 50% by weight or less, more preferably 0.01% to 40% by weight of the coating film.

Two or more kinds of the above bases or base precursors can be used.

The ratio of the above-mentioned development inhibitor precursor and base or base precursor can be selected as appropriate, but preferably the ratio of base or base precursor/development inhibitor of the present invention (molar ratio) is 1/20 to 20/1.

The compound of the present invention can be dissolved in a water-soluble organic solvent (for example, methanol, ethanol, acetone, dimethylformamide) or a mixed solution of this organic solvent and water, and then incorporated into the binder.

Hydrophobic compounds of the invention also include. It can be incorporated into the binder using the oil protection method.

The hydrophobic compound of the present invention can also be used in JP-A-59-17483
It can be made into fine particles by the method described in No. 0 and incorporated into the binder.

The development inhibitor precursor and base or base precursor of the present invention are added to any of the constituent layers of the heat-developable photographic element, such as the photosensitive layer, intermediate layer, protective layer, image-receiving layer, etc.

The heat-developable photographic element in the present invention means either a heat-developable photosensitive element or a dye-fixing element used as necessary, or both.

The base or base precursor and the development inhibitor precursor may be present in the same layer or in separate layers.
In particular, it is preferable to have both of the above coexist in the silver halide emulsion layer.

The heat-developable photosensitive element in the present invention has at least a photosensitive silver halide, a binder, and a reducing agent on a support. Among them, in order to form a color image, a dye-donating substance that releases or forms a mobile dye upon heating is further included. In this case, the dye-donating substance 1 may have a function as a reducing agent.

Silver halide that can be used in the present invention is disclosed in Japanese Patent Application No. 59-21
Silver halide produced according to the method described on pages 25 to 29 of No. 3978, containing the additives described therein, and having the properties described therein can be used.

Although the silver halide emulsion may be used unripe, it is usually used after being chemically sensitized. For emulsions for conventional light-sensitive materials, known sulfur sensitization methods, reduction sensitization methods, noble metal sensitization methods, etc. can be used alone or in combination.

The silver halide emulsion used in the present invention may be a surface latent image type in which a latent image is mainly formed on the grain surface, or an internal latent image type in which a latent image is formed inside the grains. Direct inversion emulsions combining emulsions and nucleating agents can also be used.

The coating amount of the photosensitive silver halide used in the present invention is in the range of 1 layer g to Log/rn' in terms of silver.

In the present invention, it is desirable to use an organic metal salt relatively stable to light, particularly an organic silver salt, as an oxidizing agent together with the photosensitive silver halide.

For details on organic silver salts that can be used, see Japanese Patent Application No. 59-2.
No. 13978, pages 30-34.

The silver halide used in the present invention may be spectrally sensitized with methine dyes and others.

Regarding these pigments and their details, please refer to the patent application filed in 1983.
-213978, pages 34 to 38.

In the present invention, a reducing agent is included in the photosensitive material. As the reducing agent, those known in the art and the reducing dye-providing substances described below are preferred.

As a specific example of the reducing agent used in the present invention, Japanese Patent Application No. 59
-209583, pages 61 to 64 j can be used.

In the present invention, when photosensitive silver halide is reduced to silver under high temperature conditions, a compound that generates or releases a mobile dye in response to or inversely to this reaction, i.e., a dye-donating compound, is used. It can contain sexual substances.

Next, the dye-donating substance will be explained.

Examples of dye-donating substances that can be used in the present invention include couplers that can react with a developer. This method using a coupler, in which an oxidized product of the developer produced by an oxidation-reduction reaction between a silver salt and a developer reacts with the coupler to form a dye, is described in numerous documents. Specific examples of developers and couplers are given by, for example, T.H.
The Theory of the Photographic Process (The Theory of the Photographic Process)
(photographic process) 4th edition (
4th Ed,) pages 291-334, and 354
It is described in detail in ``Photochemistry'', 4th edition (Yame Publishing), written by Makoto Kikuchi, pages 284-295, etc.

Further, a dye silver compound in which an organic silver salt and a dye are combined can also be cited as an example of the dye-donating substance.

Specific examples of dye silver compounds can be found in Research Fist Disclosure Magazine, May 1978 issue, pages 54-58 (HD-169
66) etc.

Furthermore, azo dyes used in heat-developable silver dye bleaching methods can also be cited as examples of dye-donating substances. Specific examples of azo dyes and bleaching methods are disclosed in U.S. Pat. No. 4,235.957.
No., Research Reference Disclosure Magazine, April 1976 issue, pages 30-32 (HD-14433).

Also, U.S. Patent No. 3,985,565, U.S. Patent No. 4.022
, No. 817, etc., can also be mentioned as an example of the dye-donating substance.

Further, as another example of the dye-donating substance, there can be mentioned a compound having a function of diffusing a diffusible dye in an image-wise emission wave pattern.

This type of compound can be represented by the following general formula (LL).

(D V e −X) n −Y (L 1) Dy
e represents a dye group or a dye precursor group;
Either by creating a difference in the diffusivity of the compound represented by
) represents a group having a property that causes a difference in diffusivity between n-Y, n represents 1 or 2,
When Yu was 2.

The two Dye-Xs may be the same or different.

Specific examples of the dye-donating substance represented by the general formula (Ll) include 1. For example, a dye developer in which a hydroquinone developer and a dye component are linked is disclosed in US Pat. No. 3,134,764.
No. 3, No. 362.819, No. 3,597,20
No. 0, No. 3,544.545, No. 3゜482.9
It is described in No. 72, etc. In addition, a substance that releases a sharply diffusible dye upon intramolecular nucleophilic substitution reaction was disclosed in JP-A-51-
63618, etc., a substance that releases a diffusible dye through an intramolecular rewinding reaction between inoxacilones was disclosed in Japanese Patent Application Laid-open No. 4.
No. 9-111828, etc.

In all of these methods, the diffusible dye is released or diffused in areas where development has not occurred, and the dye is neither released nor diffused in areas where development has occurred.

In another method, a dye-releasing compound is made into an oxidized form without dye-releasing ability in advance and allowed to coexist with a reducing agent or its precursor, and after development, the remaining unoxidized reducing agent is used to reduce the dye. A system for releasing a diffusible dye has also been devised, and specific examples of dye-donating substances used therein are disclosed in JP-A-53-110827 and JP-A-54-13.
No. 0927, No. 5B-164342, No. 53-355
It is described in No. 33.

On the other hand, as a substance that releases a diffusible dye in the area where development occurs, a substance that releases a diffusible dye through the reaction between a coupler having a diffusible dye as a leaving group and an oxidized form of a developer is disclosed in British Patent No. 1. No. 330.524, Special Publication 1973-39
No. 165, U.S. Pat. No. 3,443,940, etc., and U.S. Pat. No. 3, U.S. Pat. .227.550 etc.

In addition, in systems using these color developers, image contamination due to oxidative decomposition products of the developer becomes a serious problem.
In order to improve this problem, dye-donating compounds that do not require a developer and have reducing properties themselves have been devised.

Representative examples can be found in the following documents. Definitions in the general formula are described in each literature.

For example, US Pat. No. 3,928,312.

No. 4,053,312, No. 4,005゜428, No. 4,336,322, JP-A-59-65839
No. 59-69839.

No. 53-3819, No. 51-104343, Research Disclosure No. 17465, U.S. Patent No. 3,725,062, U.S. Patent No. 3,728,113, U.S. Pat.

Any of the various dye-donating substances described in No. 939, JP-A-58-116537, etc. can be used in the present invention.

Specific examples of the dye-donating substance that can be used in the present invention include the compounds described on pages 60 to 91 of the aforementioned JP-A-59-84236. The described compounds (I) to (3), (I0)
~(I3), (IB)~(ill), (28)~(3
0), (33), (35), (38) to (40)
.

(42) to (84) are preferred.
Compounds described on pages 82 and 83 of No. 246468 are also useful.

The dye-providing substances and photographic additives used in the present invention are:
They can be incorporated into the layers of the photosensitive material by known methods such as those described in US Pat. No. 2,322,027.

In that case, the above-mentioned high boiling point organic solvents and low boiling point organic solvents can be used.

Also, Japanese Patent Publication No. 51-39853, Japanese Patent Publication No. 51-5994
The dispersion method using polymers described in No. 3 can be used. In addition, a variety of surfactants can be used when dispersing the dye-donating substance in the woody colloid, including those listed as surfactants elsewhere in this specification. can be used.

In the present invention, an image formation accelerator can be used in the light-sensitive material. Image formation accelerators include accelerating redox reactions between silver salt oxidizing agents and reducing agents; accelerating reactions such as generation of dyes from dye-donating substances, decomposition of dyes, and release of mobile dyes; and photosensitive material layers. It has the function of promoting the movement of the dye from the dye fixing layer to the dye fixing layer, and from a physicochemical function, it has the function of promoting the movement of the dye from the above-mentioned base or base precursor, nucleophilic compound, oil, hot solvent, surfactant, silver or silver ion. These substances are classified as interacting compounds, etc. However, these substance groups generally have multiple functions and usually have some of the above-mentioned promoting effects.

For details of these, see Japanese Patent Application No. 59-213978 6.
It is described on pages 7-71.

Further, in the present invention, a compound that activates the development and stabilizes the image can be used in the photosensitive material.

For specific compounds that are preferably used, see Japanese Patent Application No. 1983.
-213978, pages 73-74.

In the present invention, the photosensitive material may contain an image toning agent if necessary. Specific examples of effective toning agents are described in Japanese Patent Application No. 59-213978, pages 74-75.

Binder I used in the photosensitive material of the present invention can be contained alone or in combination. A hydrophilic binder can be used for this binder.

Typical wood-loving binders include transparent or translucent wood-loving binders, such as proteins such as gelatin, gelatin derivatives, cellulose derivatives, and starch.

With natural substances like polysaccharides such as gum arabic.

including synthetic polymeric substances such as polyvinylpyrrolidone, water-soluble polyvinyl compounds such as acrylamide polymers,
Other synthetic polymeric substances include dispersed vinyl compounds in the form of latexes, which increase the dimensional stability of photographic materials, among others.

In the present invention, the binder is applied in an amount of 20 g or less per 1 rr1'', preferably 10 g or less, more preferably 7 g or less.

The ratio of the high boiling point organic solvent dispersed in the binder together with a hydrophobic compound such as a dye-donating substance and the binder is 1 g of binder to 1 g of solvent or less, preferably 0.
A suitable amount is 5 cc or less, more preferably 0.3 cc or less.

The photographic light-sensitive material and dye-fixing material of the present invention may contain an inorganic or organic hardener in the photographic emulsion layer or other binder layer.

Specific examples and specific compound examples include those described in Japanese Patent Application No. 59-213978, pages 76 to 77, and these can be used alone or in combination.

The support used in the light-sensitive material and dye-fixing material used in the present invention is one that can withstand processing temperatures. As a general support,
Not only glass, paper, metal and their analogues are used, but also Japanese Patent Application No. 59-213978, page 77~
Those listed as supports on page 78 can be used.

When using a dye-donating substance that releases an image-wise mobile dye in the present invention, a dye transfer aid can be used to transfer the dye from the photosensitive layer to the dye fixing layer.

In a system in which the transfer aid is externally supplied, water or a basic aqueous solution containing caustic soda, caustic potash, an inorganic alkali metal salt, and an organic base is used as the dye transfer aid. As these bases, those described in the section of the image formation accelerator can be used. Further, a low boiling point solvent such as methanol, N,N-dimethylformamide, acetone, diisobutyl ketone, or a mixed solution of these low boiling point solvents and water or a basic aqueous solution is used. The dye transfer aid may be used in a method in which either the dye fixing material or the light-sensitive material or both are wetted with the transfer aid.

When the light-sensitive material used in the present invention contains a colored dye-donating substance, it is not so necessary to further contain an irradiation-preventing substance, an anti-halation substance, or various dyes. However, it is described in the literature exemplified on page 80 of Japanese Patent Application No. 59-213978.
, 5 filter dyes, absorbent substances, etc. can be contained.

The photosensitive material used in the present invention may optionally contain various additives known as heat-developable photosensitive materials and components below the photosensitive layer, such as an antistatic layer, a conductive layer, a protective layer, an intermediate layer,
It can contain an H layer, a release layer, etc. For various additives, see Research Disclosure Magazine Vol.

170. Additives described in June 1978 (7) No. 17029, such as plasticizers, sharpness improving dyes, AH dyes, sensitizing dyes, matting agents, surfactants, optical brighteners, There are additives such as anti-fading agents.

The photographic elements of this invention optionally are photosensitive elements that form or release dyes upon thermal development.

It consists of a dye fixing element that fixes the dye.

In particular, in systems that form images by diffusion transfer of dyes, a photosensitive element and a dye fixing element are essential, and in a typical form, the photosensitive element and dye fixing element are separately coated on two supports. It is broadly divided into two types: a form in which it is coated on the same support and a form in which it is coated on the same support.

The relationship between the photosensitive element and the dye fixing element, the relationship with the support,
Regarding the relationship with the white reflective layer, the relationship described on pages 81 to 82 of Japanese Patent Application No. 59-213978 can also be applied to the present application.

A typical configuration in which the photosensitive element and the dye-fixing element are coated on the same support is a configuration in which there is no need to peel off the photosensitive element from the image-receiving element after the transfer image is formed. In this case, the dye fixing layer of the photosensitive layer 1 and the white reflective layer are laminated on a transparent or opaque support. A preferred embodiment is 1, for example, 8 of Japanese Patent Application No. 59-213978.
The description is on the 5th line to the 2nd line from the bottom of page 2.

Another typical embodiment in which the light-sensitive element and the dye-fixing element are coated on the same support is disclosed in JP-A-56-67840, for example.
Canadian Patent No. 674°082, U.S. Patent No. 3,7
30,718, in which part or all of the photosensitive element is stripped from the dye fixing element.

Examples include those having a release layer coated at an appropriate position.

The photosensitive element or dye-fixing element may have a conductive heating layer as a heating means for thermal development or diffusion transfer of the dye.

In order to obtain a wide range of colors in the chromaticity diagram using the three primary colors yellow, magenta, and cyan, the light-sensitive element used in the present invention is a silver halide compound sensitive to at least three different spectral regions. It is necessary to have an emulsion layer.

Typical combinations of at least three photosensitive silver halide emulsion layers sensitive to different spectral regions include Japanese Patent Application No. 59-213978, 83-84.
There is something written on page 7 line.

The light-sensitive material used in the present invention may have two or more emulsion layers sensitive to the same spectral region, depending on the sensitivity of the emulsion, if necessary.

The above-mentioned emulsion layers and/or the non-photosensitive wood-philic colloid layers adjacent to each emulsion layer are
It is necessary to contain at least one of the compounds listed in the 7th line from the bottom of page 82 of the specification of No. 3978 to the 8th line of page 85.

In addition to the above-mentioned layers, the photosensitive material used in the present invention may be provided with auxiliary layers such as a protective layer, an intermediate layer, an antistatic layer, an anti-curl layer, a release layer, and a matting agent, as required.

In particular, the protective layer (PC) usually contains an organic or inorganic matting agent to prevent adhesion. In addition, this protective layer may contain a mordant, a UV absorber, etc.
The protective layer and the intermediate layer may each be composed of 2R or more.

In addition, the intermediate layer may contain a reducing agent to prevent color mixing, a UV absorber, and a white pigment such as TiO2.The white pigment may be added not only to the intermediate layer but also to the emulsion layer for the purpose of increasing sensitivity. Good too.

The dye fixing element used in the present invention has at least one layer containing a mordant, and when the dye fixing layer is located on the surface, a protective layer can be further provided if necessary.

The layer structure of the dye fixing element, the binder, additives, and mordant addition location are as described in Japanese Patent Application No. 59-213978, No. 8.
The descriptions from page 6, line 10 to page 88, line 10 and the patent specifications described therein are also applicable to the present application.

In addition to the above-mentioned layers, the dye fixing element used in the present invention can be provided with auxiliary layers such as a release layer, a matting agent layer, and an anti-curl layer, if necessary.

One or more of the above layers may include a base and/or base precursor to promote dye transfer, a hydrophilic thermal solvent, an antifade agent to prevent color mixing of the dye, a UV absorber, a dimensional stability Dispersed vinyl compound for increasing
A fluorescent whitening agent or the like may be included.

The binder in the above layer is preferably hydrophilic, and transparent or semitransparent woody colloids are typical. Specifically, the binders mentioned above for the photosensitive materials are used.

Furthermore, it is advantageous for the dye fixing element of the present invention to contain a transfer aid as described below. The transfer aid may be included in the dye fixing layer, or may be included in a separate layer.

In the present invention, the transparent or opaque heat generating element when electrical heating is employed as the developing means can be made using conventionally known techniques as a resistance heating element.

As a resistance heating element, there are two methods: a method using a thin film of an inorganic material exhibiting semiconductivity, and a method using a thin film of an organic material in which conductive fine particles are dispersed in a binder. Materials that can be used in these methods are disclosed in Japanese Patent Application No. 59-213978, No. 8.
Those described on page 9, lines 2 to 13 can be used according to the method and layer structure described therein according to the distinctions described therein.

Regarding the mutual positional relationship of the heat generating element and the photosensitive element, the same as described in the fifth line from the bottom of page 89 to the end of the page can be applied.

The image receiving layer in the present invention includes a dye fixing layer used in heat-developable color light-sensitive materials, and can be arbitrarily selected from commonly used mordants, among which polymer mordants are particularly preferred. What is a polymer mordant?

These include polymers containing a tertiary amino group, polymers having a nitrogen-containing heterocyclic moiety, and polymers containing these quaternary cation groups.

Regarding this specific example, please refer to Japanese Patent Application No. 59-213978.
It is described in the literature illustrated on pages 1 to 91.

In the present invention, the method described on pages 91 to 92 of the specification of the above application number can be applied to the method of coating the heat-developable photosensitive layer, protective layer, intermediate layer, undercoat layer, back layer, and other layers.

As a light source for image exposure for recording an image on a heat-developable photosensitive material, radiation including visible light can be used,
For example, the light source described on page 92 of Japanese Patent Application No. 59-213978 can be used.

The heating temperature in the heat development step can be developed at about 0°C to about 250°C, and particularly useful is about 10°C to about 180°C. The heating temperature in the transfer process can be in the range from the temperature in the heat development process to room temperature, but it is particularly preferable to lower the temperature by about 10 degrees Celsius than the temperature in the heat development process.Heating in the development and/or transfer process As the means, a simple hot plate, iron, hot roller, heating element using carbon, titanium white, etc. can be used.

Also useful is a method in which development and transfer are carried out simultaneously or sequentially, as detailed in JP-A No. 59-218443. In this method, the above-mentioned image formation accelerator and/or dye transfer aid may be included in advance in either or both of the dye fixing material and the light-sensitive material, or may be supplied from the outside.

In this system where development and transfer are performed simultaneously or continuously, the heating temperature is preferably 60°C or higher and below the boiling point of the solvent used for transfer. For example, when the transfer solvent is water, 60°C
It is desirable that the temperature is between 100°C and 100°C.

A dye transfer aid (for example, water) is added between the photosensitive layer of a heat-developable photosensitive material and the dye fixing layer of a dye fixing material to promote image transfer. Alternatively, a dye transfer aid may be applied to both, and then the two may be superimposed.

As a method for applying a dye transfer aid to a photosensitive layer or a dye fixing layer, for example, Japanese Patent Application No. 59-213978 No. 93
There are methods described in lines 6 from the bottom of the page to lines 2 from the bottom of page 94.

The heating means in the transfer process is disclosed in Japanese Patent Application No. 59-21397.
There is a means described in No. 8, page 94, last line to page 95, line 10.

Alternatively, a layer of an electrically conductive material such as graphite, carbon black, or metal may be applied to the dye-fixing material in an overlapping manner, and an electric current may be passed through this electrically conductive layer to heat it directly.

The heating temperature applied in the transfer step can be in the range from the temperature in the heat development step to room temperature, but in particular 6
The temperature is preferably 0° C. or more and 10° C. or more lower than the temperature in the heat development step.

The pressure conditions and method of applying pressure when overlapping the heat-developable photosensitive material and the dye-fixing material and bringing them into close contact are described in Japanese Patent Application No. 59-2.
The method described on page 96 of No. 13978 can be applied.

■Specific Effects of the Invention According to the present invention, since it contains at least a base or base flexor-1 and a photographic reagent capable of releasing the compound represented by the general formula (I) by the action of the base, A thermally developable photographic element is obtained in which development can be stopped at an appropriate time without reducing the achieved density. Furthermore, unevenness in image density due to variations in heating temperature can be prevented.

① Specific Examples of the Invention One specific example of the present invention will be shown below, and the effects of the present invention will be explained in more detail.

Example 1 This article describes how to make a silver iodobromide emulsion.

740 g of gelatin and 26 g of KBr were dissolved in 3000 d of water. This solution was kept at 50°C and stirred.

Next, a solution of 34 g of silver nitrate dissolved in 200 dl of water was added to the above solution over a period of 10 minutes.

Thereafter, a solution prepared by dissolving 3.3 g of KI in 100 Il11 of water was added over 2 minutes.

The pH of the silver iodobromide emulsion thus prepared was adjusted, and the emulsion was allowed to settle to remove excess salt.

Thereafter, the pH was adjusted to 8.0, yielding 400 g of a silver iodobromide emulsion.

Next, we will describe how to make a gelatin dispersion of a dye-donating substance.

5 g of yellow dye-donating substance (5 g of surfactant), 0.5 g of sodium succinate-2-ethyl-hexyl ester sulfonate, 10 g of tri-iso-nonyl phosphate, and 30 mJI of ethyl acetate were added.
The mixture was heated and dissolved at about 60°C to form a uniform solution. This solution and 100 g of a 10% solution of lime-treated gelatin were stirred and mixed, and then dispersed using a homogenizer for 10 minutes at 10.OOORPM. This dispersion is called a yellow dye-providing substance dispersion.

A dispersion of a magenta dye-providing substance was prepared in the same manner as described above except that magenta dye-providing substance (2) was used. Similarly, a cyan dispersion containing the cyan dye-providing substance (3) was prepared.

Dye-Donating Substance (I) Next, a method for preparing a gelatin dispersion of the compound of the present invention will be described.

3 g of the compound (5) of the present invention was added to 100 g of a 1% gelatin aqueous solution.
g and was ground in a mill for 10 minutes with 100 g of glass beads having an average particle size of about 0.6 mm. The glass peas were separated by filtration to obtain a gelatin dispersion of the compound of the present invention.

Color photosensitive materials having a multilayer structure as shown in the table below were made from these materials.

-I D-2 Next, photosensitive materials B and C were prepared using the same recipe using compounds (20) and (27) of the present invention instead of compound (5) of the present invention in photosensitive material A. Ta.

For comparison, a photosensitive material not containing the compound of the present invention was also prepared in the same manner.

Next, a method for forming a dye-fixing material having an image-receiving layer will be described.

First, 0.75 g of gelatin hardener H-1, 0.25 g of H-2, 160 g of water and 100 g of 10% lime-treated gelatin were uniformly mixed. This mixed solution was uniformly applied onto a paper support laminated with polyethylene in which titanium oxide was dispersed to form a wet film of 60 mm, and then dried.

Gelatin hardener H-1 CH2= CHS O2CH2CON HCH2CH2
NHCOCH2・5O2CH =CH2 Gelatin hardener H-2 CH2= CHS O2CH2CON HCH2・CH
2CH2NHCOCH2502 CH,=CH2 Next, polymer 15ge having the following structure was dissolved in 200 tt of water and uniformly mixed with 100 g of 105 lime-treated gelatin.

This mixed solution was uniformly applied onto the above-mentioned coating material to form a wet film of 85 mm. This sample was dried and used as a dye fixing material.

Cow Polymer Using a tungsten light bulb, the color photosensitive material with the multilayer structure described above was exposed to light at 2000 lux for 10 seconds through a three-color separation filter of B, G, and H whose density was continuously changed, and then heated to 150°C or 153°C. The mixture was heated uniformly for 20 seconds on a heated heat block.

After soaking the image-receiving material in water, the heated photosensitive material A-
D were stacked one on top of the other so that their membrane surfaces were in contact with each other.

After heating on a heat block at 80° C. for 6 seconds, the image-receiving material was peeled off from the light-sensitive material, and a negative magenta color image was obtained on the image-receiving material. The density of this negative image was measured using a Macbeth reflection densitometer (RD-519).

The results are shown in Table 1.

Table 1 Heating at 150°C for 20 seconds according to the present invention 15
Heated sample at 3℃ for 20 seconds Filter
□Compound Nb M Large concentration Minimum concentration Maximum concentration Minimum concentration B 1.90. 0.18
1,93 0.19A (5)
G 2.00 0. +8 2.
04 0.20R2,080,182,130,1
8'B 1.94 0. lfi 1
．． 99 Q, 18B (20)
G 2.02 0.20 2.0?
0.23R2,+2 0.20 2.
15 0.22B 1.89 0.
15 1. ! 13 0.18C (27)
G 2.0+ 0.17 2
．． 0? 0.111R2,0? 0. +
9 2.10 0.21B 1.9
5 0.18 2.03 0.3+
D None G 2.04 0
．． 20 2.18 0.41
・(Comparison) R2, 120, 17
2100,29 Table 1 shows that when the compound of the present invention is used, even if the developing temperature is raised by 3°C, there is little increase in both the maximum density and the minimum density.On the other hand, the comparative example in which the compound of the present invention is not added has no fog. increases significantly. Therefore, it can be seen that the compound of the present invention has a high temperature compensation effect.

Example 2 This article describes how to make a silver halide emulsion for use in the fifth calendar.

A well-stirred aqueous gelatin solution (20 g of gelatin and ammonia dissolved in 1000 cc of water and kept at 50°C) was mixed with 1000 g of an aqueous solution containing potassium iodide and potassium bromide and a silver nitrate solution (100 g of water).
(1 mole of silver nitrate dissolved in 00d) was added at the same time while keeping the pag constant. In this way, a monodisperse silver iodobromide octahedral emulsion (5 mol % of iodine) with an average grain size of 0.5 uL was prepared.

After washing with water and desalting, 5 mg of chloroauric acid (tetrahydrate) and 2 g of sodium thiosulfate were added to perform gold and sulfur sensitization at 60°C. The yield of emulsion is 1. It was OKg. Next, I will talk about how to make the emulsion for the third layer.

A well-stirred gelatin aqueous solution (20 g of gelatin and 3 parts of sodium chloride in 1,000,111 parts of water)
600 d of an aqueous solution containing sodium chloride and potassium bromide (containing 600 d of water and kept at 75°C), an aqueous silver nitrate solution (0,053 mol of silver nitrate dissolved in 600 d of water), and the following dye solution (I). , simultaneously added in equal drop amounts over 40 minutes. In this way, a monodisperse cubic silver chlorobromide emulsion (bromine 80 mol %) having an average grain size of 0.35 tL and adsorbing a dye was prepared.

After washing with water and desalting, 51 g of sodium thiosulfate and 20 g of 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene were added to carry out chemical sensitization at 60°C. The yield of emulsion was 600 g.

Next, the method for preparing the emulsion for the first layer will be described.

A well-stirred aqueous gelatin solution (20 g of gelatin and 3 g of sodium chloride in 1000 d of water kept at 75°C) was mixed with an aqueous solution 600111I containing sodium chloride and potassium bromide and an aqueous silver nitrate solution (600 III of water with 0 silver nitrate). 0.59 mol dissolved) was simultaneously added in equal dropwise amounts over 40 minutes. In this way, a monodisperse cubic silver chlorobromide emulsion (80 mol % bromine) with an average grain size of 0.351 L was prepared.

After washing with water and desalting, 5 g of sodium thiosulfate and 4-hydroxy-6-methyl-1,3,3a,7-titrazaindene 20B were added to carry out chemical sensitization at 60°C. The yield of emulsion was 600 g.

Next, a method for preparing a benzotriazole silver emulsion will be described.

28g of gelatin and 13.2g of benzotriazole to 33g of water
000-. This solution is kept at 40°C and stirred. A solution prepared by dissolving 17 g of silver nitrate in 100 g of water was added to this solution over 2 minutes.

The pH of the benzotriazole silver emulsion was adjusted and allowed to settle to remove excess salt. Thereafter, the pH was adjusted to 8oO, and a yield of 400 g of benzotriazole silver emulsion was obtained.

A dispersion of a dye-providing substance was prepared in the same manner as in Example 1.

A color photosensitive material E having a multilayer structure as shown in the primary table was prepared using these materials.

Next, we will discuss how to make the dye fixing material.

12 g of lime-treated gelatin was dissolved in 20 ld of water, and 18 d of a 0.5 M zinc acetate aqueous solution was added thereto and mixed uniformly. It was coated uniformly to a thickness of 85 mm. Next, prepare the following coating liquid on top of this and use 901ffl of wear)
A dye-fixing material was prepared by uniformly applying the dye to a thickness of 1/2 inch and drying.

Dye fixing layer coating solution prescription F> Polyvinyl alcohol (degree of polymerization 2000) 10% aqueous solution 120g urea
20g N-methylurea
20g (intrinsic viscosity 0.1728; measured at 30°C in a 1% NaC aqueous solution) Compound (5) of the present invention (described in Example 1) 6 (Dye fixing layer coating formulation G) Polyvinyl alcohol (polymerized degree 2000) 10% aqueous solution 120g urea
20g N-methylurea
20g water
60d Using a tungsten light bulb, the color photosensitive material with the above multilayer structure was exposed to light at 2000 lux for 1 second through a three-color separation filter of B, G, and H whose temperature was continuously changed. Thereafter, it was heated uniformly for 20 seconds on a heat block heated to 150°C.

This photosensitive material and the previously prepared dye fixing material were placed one on top of the other so that their film surfaces were in contact with each other, passed through a pressurized heat roller at 130°C, and immediately heated at 120°C for 30 seconds on a heat block. Immediately after heating, the dye-fixing material was peeled off from the light-sensitive material, and yellow, magenta, and cyan color images were obtained on the dye-fixing material corresponding to the B, G, and H three-color separation filters, respectively. The maximum density and minimum density of each color were measured using a Macbeth reflection densitometer (RD 519). The results are as follows.

(Present invention) (Comparison) Concentration Concentration Concentration Concentration B 1.88 0.18 1.110 0
．． 28G 2.12G, 19 2.1
2 G, 32R2,200, 1!11 2.25
It can be seen that when the compound of the present invention is added to the dye fixing layer as 0.211 or more, it has the effect of suppressing the increase in fog during the transfer process.

Example 3 Weigh the log of the dye-donating substance (4) and the log of co/ The mixture was heated and dissolved at ℃ to form a homogeneous solution. This solution and 100 g of a 10% aqueous solution of lime-treated gelatin were stirred and mixed, and then emulsified and dispersed using a homogenizer.

Next, a photosensitive material H was prepared as follows.

(a) 5.5 g of silver iodobromide emulsion of Example 1 (b)
10% gelatin aqueous solution 0.5g (c) Dispersion of the above dye-donating substance 2.5g (d) Guanidine trichloroacetic acid solution in □lO% ethanol
1- (e) 10% methanol solution of 2,8-dichloro-4-aminophenol 0.5% (f) 5% aqueous solution of the compound with the following structure 1mllcgHp++ (ll
l & C) I20)a H(g) Compound of the present invention (5)
gelatin dispersion of 0.5 d(
h) Water 8d The above (a) and (b) were mixed and heated to dissolve, and then coated on a polyethylene terephthalate film to a wet film thickness of 85 mm.

Add 1.5g/gelatin as a protective layer on top of this film.
A photosensitive material H was prepared by coating the photosensitive material H.

The above photosensitive material H was heated using a tungsten light bulb for 2000
Imagewise exposure for 10 seconds at lux.

It was heated uniformly for 30 seconds on a heat block heated to 140°C or 143°C.

Next, this was treated in the same manner as in Example 1, and the following results were obtained.

Heating at 140°C for 30 seconds Heating at 143°C for 30 seconds Maximum concentration Minimum concentration Maximum concentration Minimum concentration H2,010,17
2,040,2G It can be seen from the above results that the effect of the compound of the present invention is remarkable even in light-sensitive materials containing a dye-donating substance that releases a dye through a coupling reaction with an oxidation product of a developer.

Example 4 5 g of dye-donating substance (5) having the following structure, 4 g of electron donor having the following structure, 0.5 g of sodium succinate 2-ethylhexyl ester sulfonate, 10 g of licresyl phosphate, and cyclohexanone Add 20-, about 6
The mixture was heated and dissolved at 0°C. The rest was carried out in the same manner as in Example 3 to prepare a dispersion of a reducible dye-providing substance.

Dye-donating substance (5) Electron donor These manufacturing methods were used except that the dispersion of the reducible dye-donating substance described above was used instead of the dispersion of the dye-donating substance (4) in photosensitive material H of Electron donor Example 3. Photosensitive materials I were prepared in exactly the same manner as above.

This photosensitive material I was exposed and processed in the same manner as in Example 3, and the measurements were as follows.

Heating at 14゛0℃ for 30 seconds Heating at 143℃ for 30 seconds Maximum concentration Minimum concentration Maximum concentration Minimum concentration I 1.7
8 0.19 1.80 0.21 The above results confirm the effectiveness of the compound of the present invention in light-sensitive materials containing the above-mentioned reducible dye-providing substance capable of forming a positive image in contrast to a silver image. .

Example 5 Preparation of gelatin dispersion of coupler Weigh out 5 g of 2-dodecylcarbamoyl-1-naphthol, 0.5 g of amber m-2-ethyl-hexyl ester sulfo 7M soda, and 2.5 g of tricresyl phosphate (TCP). Then, 30 d of ethyl acetate was added and dissolved. This solution and 100 g of a 10% gelatin solution were stirred and mixed, and mixed with a homogenizer for 10 minutes. Dispersed using OOORPM.

Next, photosensitive material J was prepared as follows.

(a) Silver iodobromide emulsion (from Example 1) 10 g (b) Gelatin dispersion of coupler 3.5 g (C) 0.25 g of guanidine trichloroacetic acid dissolved in 2.5 cC of ethanol (d) Gelatin ( I0% aqueous solution) 5g (e)
2,8-dichloro-p-7 minophenol
A solution prepared by dissolving 0.2 g in 15 cc of water (f) A gelatin dispersion of the compound (5) of the present invention (as described in Example 1) 1 - A coating having the above composition was coated on a polyethylene terephthalate support for 60 - A photosensitive material was prepared by coating the film to a wet film thickness of 100 ml and drying it.

This photosensitive material is used in a tungsten light bulb.

Imagewise exposure was made for 5 seconds at 2000 lux. then 15
20 minutes on a heat block heated to 0°C or 153°C.
When heated uniformly for seconds, a negative cyan image was obtained. Measure this concentration using a Macbeth transmission densitometer (TD-504).
When the measurement was carried out using the following, the following results were obtained.

J 2.0$ 0.17 2.11
It can be seen that the compound of the present invention has a high temperature compensation effect as shown in the value of 0.21 or more.

Example 6 Next, a black and white embodiment will be described.

Photosensitive material K was prepared as follows.

(a) Silver iodobromide emulsion (as described in Example!) 1 g (b) Silver benzotriazole emulsion 10 g (as described in Example 2) (C) 10% ethanol solution of guanidine trichloroacetic acid 1ce (d) Below 2 cc of a 5% methanol solution of the compound represented by the structural formula (e) Gelatin dispersion of the compound (5) of the present invention (as described in Example 1)
Icc The above coating solution was coated on a polyethylene terephthalate support to a wet film thickness of 60 mm and dried.

This photosensitive material is used with a tungsten light bulb.

Imagewise exposure was made for 5 seconds at 2000 lux. then 13
30 minutes on a heat block heated to 0°C or 133°C.
When heated evenly for seconds.

A negative brown image was obtained. When this concentration was measured using a Macbeth transmission densitometer (TD-504), the following results were obtained.

Maximum concentration Minimum concentration Maximum concentration Minimum concentration K O
, 840, 100, 880, 13, it can be seen that the compound of the present invention has a high temperature compensation effect.

Claims (1)

[Scope of Claims] A heat-developable photographic element comprising at least a base or a base precursor, and a photographic reagent capable of releasing a compound represented by the following general formula (I) by the action of the base. General Formula (I) R^0-SH {In the above general formula (I), R^0 represents a substituted or unsubstituted alkyl group, cycloalkyl group, aralkyl group, alkenyl group or aryl group. }