JPS6227379B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for forming color images by thermal development. The present invention particularly includes:
In a heat-developable color photosensitive material containing a dye-donating substance that releases a diffusible dye upon heat development, a color image is obtained by thermal diffusion transfer of the dye released by heat development onto a dye-receiving support. It is about new methods. Photography using silver halide has superior photographic properties such as sensitivity and gradation control compared to other photographic methods such as electrophotography and diazo photography.
It has traditionally been the most widely used. In recent years, a technology has been developed that allows images to be easily and quickly obtained by changing the image forming method for photosensitive materials using silver halide from the conventional wet processing using a developer to a dry processing using heating, etc. It has been. Heat-developable photosensitive materials are well known in the art, and the heat-developable photosensitive materials and their processes are described in U.S. Pat.
No. 3457075, British Patent No. 1131108, No. 1167777
issue and Research Disclosure Magazine, June 1978 issue, pages 9-15 (RD-17029). For information on how to obtain a color image,
Many methods have been proposed. Regarding the method of forming a color image by combining an oxidized form of a developer with a coupler, U.S. Pat.
Aminophenol reducing agent received Belgian patent no.
Issue 802519 and Research Disclosure Magazine
September 1975 issue, pages 31 and 32, proposes a sulfonamidophenol reducing agent, and US Pat. No. 4,021,240 proposes a combination of a sulfonamidophenol reducing agent and a 4-equivalent coupler. However, in such a method, a reduced silver image and a color image are simultaneously generated in the exposed area after thermal development, so that the color image becomes cloudy. To solve this problem, there are methods to remove the silver image by liquid processing or to transfer only the dye to another layer, such as a sheet with an image-receiving layer. It has the disadvantage that it is not easy to transfer. In addition, a method of introducing a nitrogen-containing heterocyclic group into a dye, forming a silver salt, and releasing the dye by heat development is described in Research Disclosure Magazine, May 1978 issue 54.
Described on page 58 RD-1966. With this method, it is difficult to suppress the release of dye in areas not exposed to light, and a clear image cannot be obtained, so it is not a common method. Further, regarding the method of forming positive color images by thermal silver dye bleaching method, see, for example, Research Disclosure Magazine, April 1976 issue, pages 30-32 (RD-14433), December 1976 issue, pages 14-15 of the same magazine. Page (RD-15227), U.S. Pat. No. 4,235,957, and others, useful dyes and bleaching methods are described. However, this method requires extra steps and materials, such as stacking and heating activator sheets to accelerate the bleaching of the dye, and the resulting color images may coexist during long-term storage. It had the disadvantage of being gradually reductively bleached by free silver and the like. Further, regarding the method of forming color images using leuco dyes, for example, US Pat. No. 3,985,565,
No. 4022617. However, this method has the disadvantage that it is difficult to stably incorporate the leuco dye into the photographic material, and the material gradually becomes colored during storage. The present invention provides a new method for forming color images by thermal development and solves the drawbacks of hitherto known materials. That is, an object of the present invention is to provide a new image forming method in which a color image is obtained by thermally transferring a hydrophilic dye released by thermal development to an image receiving material containing a mordant. An object of the present invention is to provide a method for obtaining clear color images using a simple method. An object of the present invention is to provide a method for obtaining color images that are stable over a long period of time. For these purposes, at least a photosensitive silver halide, an organic silver salt oxidizing agent, a hydrophilic binder, a dye release aid, and an organic silver salt oxidizing agent which are reducible to the support and which release a hydrophilic dye are formed on the support. This can be achieved by using a heat-developable color photosensitive material containing a dye-providing substance. The heat-developable color photosensitive material of the present invention can be used to create a negative version of the original by simply performing heat development after image exposure.
It is possible to simultaneously provide a silver image having a positive relationship and a diffusible dye in the area corresponding to the silver image. That is, when the heat-developable color photosensitive material of the present invention is imagewise exposed and heat-developed, an oxidation-reduction reaction occurs between the organic silver salt oxidizing agent and the reducing dye-donating substance using the exposed photosensitive silver halide as a catalyst. , a silver image appears in the exposed area. In this step, the dye-donating substance is oxidized by an organic silver salt oxidizing agent,
Becomes an oxidant. This oxidant is cleaved in the presence of a dye release aid, resulting in the release of a hydrophilic, diffusible dye. Therefore, a silver image and a diffusible dye are obtained in the exposed area, and a color image is obtained by transferring the diffusible dye. All reactions that release the diffusible dyes of the present invention are carried out under dry conditions at elevated temperatures. This release reaction of the diffusible dye is thought to be caused by attack by a so-called nucleophile, and is usually carried out in a liquid.
In the present invention, although it depends on the type of dye-providing compound, the compounds cited as preferred examples showed a high reaction rate even in a dry film. This high response rate is an unexpected finding. Furthermore, the dye-donating compound of the present invention can undergo a redox reaction with a silver halide or organic silver salt oxidizing agent without the aid of a so-called auxiliary developer. This is an unexpected result based on previous findings at temperatures around room temperature. The reducing dye-donating substance that releases the hydrophilic diffusible dye used in the present invention is represented by the following general formula (). Here, G is a hydroxyl group or a group that gives a hydroxyl group by hydrolysis, Col is a pigment or a group that gives a pigment,
R is an alkyl or aromatic group. The alkyl groups and alkyl residues mentioned above include unsubstituted and substituted alkyl groups as well as straight chain, branched and cyclic alkyl groups. In particular, in the above, specific examples of G include acyloxy groups such as acetoxyl group and propionyloxy group in addition to hydroxyl group. As G, a hydroxyl group is particularly preferable. Examples of Col include groups such as azo dyes, azomethine dyes, indoaniline dyes, indophenol dyes, triphenylmethane dyes, anthraquinone dyes, indigo dyes, and metal complex salts thereof. Typical dye-giving groups represented by Col include those that give dyes through hydrolysis,
For example, as described in JP-A-48-125818, U.S. Pat. By temporarily shortening the wavelength of dye absorption during exposure through acylation, it is possible to prevent desensitization due to light absorption when these color image forming agents are mixed with light-sensitive emulsions and coated. can. For this purpose, it is also possible to use a dye that has different hues when transferred onto the mordant and when present in the emulsion layer. Note that the Col moiety can have a group that imparts water solubility, such as a carboxyl group or a sulfonamide group. Preferred examples of R include linear or branched alkyl groups having 1 to 30 carbon atoms (e.g. methyl,
ethyl, propyl, butyl, pentyl, hexyl, octyl, dodecyl, pentadecyl, hexadecyl, octadecyl, isopropyl, isobutyl, t-butyl, t-amyl, neopentyl, etc.)
and substituted alkyl groups (e.g. hydroxyethyl,
benzyl, methoxyethyl, etc.); phenyl group; substituted phenyl group (eg, p-amylaminophenyl, p-nitrophenyl, etc.). In order to prevent these compounds from diffusing during thermal development, they require a ballast group that substantially prevents diffusion. The size or number of carbon atoms required for the ballast group varies depending on the conditions used, such as the time and temperature of heat development, and the number and type of water-soluble groups in the Col part, but at least 8 or more is required. It is. If the number of carbon atoms becomes larger than necessary, it becomes disadvantageous in terms of solubility and extinction coefficient, but in principle there is no upper limit to the number of carbon atoms. Generally, the most preferable range is around 13 to 40 carbon atoms. In the most preferred embodiment of the invention, G is a hydroxyl group and R is a dodecyl, tetradecyl, hexadecyl or octadecyl group. The properties required of the dye-donating substance represented by Col of the present invention include the following. 1. To be rapidly oxidized by an organic silver salt oxidizing agent and to efficiently release a diffusible dye for image formation by the action of a dye release aid. 2. The dye-donating substance must be immobilized in a hydrophilic or hydrophobic binder, and only the released dye must be diffusible. 3. Excellent stability against heat and dye release aids, and should not release image-forming dyes until oxidized. 4. Easy to synthesize. Dyes that can be used as image-forming dyes include azo dyes, azomethine dyes, anthraquinone dyes, naphthoquinone dyes, styryl dyes, nitro dyes, quinoline dyes, carbonyl dyes, and phthalocyanine dyes, and representative examples are shown by hue. In addition,
These dyes can also be used in a temporarily short-waveformed form that can be restored during development. yellow Magenta cyan

【formula】 【formula】

In the above formula, R ₁ to _{R 6} are each a hydrogen atom, an alkyl group, a cycloalkyl group, an aralkyl group, an alkoxy group, an aryloxy group, an aryl group, an acylamino group, an acyl group, a cyano group, a hydroxyl group, an alkylsulfonylamino group, Arylsulfonylamino group, alkylsulfonyl group, hydroxyalkyl group, cyanoalkyl group, alkoxycarbonylalkyl group, alkoxyalkyl group, aryloxyalkyl group, nitro group, halogen, sulfamoyl group, N-substituted sulfamoyl group, carbamoyl group, N- It represents a substituent selected from a substituted carbamoyl group, an acyloxyalkyl group, an amino group, a substituted amino group, an alkylthio group, and an arylthio group, and the alkyl group and aryl group moiety in these substituents further include a halogen atom, hydroxyl group, cyano group, acyl group, acylamino group, alkoxy group, carbamoyl group, substituted carbamoyl group, sulfamoyl group, substituted sulfamoyl group,
carboxyl group, alkylsulfonylamino group,
It may be substituted with an arylsulfonylamino group or a ureido group. The characteristics required for image-forming dyes are (1) having a hue suitable for color reproduction, (2) having a large molecular extinction coefficient, and (3) being sensitive to light, heat, and the dye release aid contained in the system. Examples include being stable against other additives, (4) being easy to synthesize, and (5) having a hydrophilic group. Specific examples of preferred image-forming dyes satisfying these conditions are shown below.
Here, H ₂ N-SO ₂ represents a bonding site with a reducing substrate. Yellow Magenta Hydrophilic groups include hydroxyl group, carboxyl group, sulfo group, phosphoric acid group, imide group, hydroxamic acid group, quaternary ammonium group, carbamoyl group, substituted carbamoyl group, sulfamoyl group, substituted sulfamoyl group, sulfamoylamino group, substituted Examples include a sulfamoylamino group, a ureido group, a substituted ureido group, an alkoxy group, a hydroxyalkoxy group, and an alkoxyalkoxy group. In the present invention, those whose hydrophilicity is significantly increased by proton dissociation under basic conditions are particularly preferred (PKa<12), and these include phenolic hydroxyl groups, carboxyl groups, sulfo groups, phosphoric acid groups, and imide groups. , a hydroxamic acid group, a (substituted) sulfamoyl group, a (substituted) sulfamoylamino group, and the like. Next, specific examples of preferred dye-providing substances will be shown. Next, a method for synthesizing the dye-donating substance will be described. Generally, the dye-donating substance of the present invention is obtained by condensing an amino group of a reducing substrate with a chlorosulfonyl group of an image-forming dye moiety. The amino group of the reducing substrate R can be introduced by reduction of a nitro, nitrone, or azo group or ring opening of a benzoxazole depending on the type of substrate, and can be used as a free base or as a salt of an inorganic acid. . On the other hand, the chlorosulfonyl group in the image-forming dye moiety can be derived from the sulfonic acid or sulfonate of the dye by a conventional method, ie, by the action of a chlorinating agent such as phosphorus oxychloride, phosphorus pentoxide, or thionyl chloride. Synthesis methods of dye moieties and their sulfonyl chlorides are described in JP-A-48-12581, 48-33826, 49-
No. 11442, No. 49-126332. The condensation reaction between the reducing substrate R and the image-forming dye part Col is generally carried out in an aprotic polar solvent such as dimethylformamide, dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, acetonitrile, etc. using pyridine, picoline, lutidine, triethylamine, It can be carried out in the presence of an organic base such as diisopropylethylamine at a temperature of 0 to 50°C, and the desired dye-donating substance can usually be obtained in a very good yield. An example of its synthesis is shown below. Synthesis Example 1 Synthesis of 4-hydroxy-3-(1,1,3,3-tetramethylbutyl)phenylbenzenesulfonate Dissolve 200g of (1,1,3,3-tetramethylbutyl)hydroquinone in 200ml of acetonitrile, 91 ml of pyridine was added. Next, 175 g of benzenesulfonyl chloride was added dropwise, and the mixture was heated under reflux for 5 hours. After cooling the reaction solution, 1.1 g of 0.8% hydrochloric acid was added, the precipitated crystals were collected, and 4-hydroxy-
326 g of 3-(1.1.3.3-tetramethylbutyl)phenylbenzenesulfonate was obtained. mp143−145℃ Synthesis example 2 4-hexadecyloxy-3-(1・1・3・
Synthesis of 3-tetramethylbutyl)phenyl benzenesulfonate 4-hydroxy-3- synthesized in Synthesis Example 1
237 g of (1,1,3,3-tetramethylbutyl)phenylbenzenesulfonate was dissolved in 474 ml of DMF. After adding 30.3 g of sodium hydroxide, 229.6 g of 1-bromohexadecane was added dropwise at 50 to 55°C.
After stirring at 55°C for 2 hours, the mixture was poured into water and extracted with 700ml of ethyl acetate. After distilling off ethyl acetate under reduced pressure, 1200 ml of ethanol was added, and after cooling to 0°C, the precipitated crystals were collected and 4-hexadecyloxy-
322.1 g of 3-(1.1.3.3-tetramethylbutyl)phenyl benzenesulfonate was obtained. mp42-43℃ Synthesis Example 3 Synthesis of 2-acetylamino-4-hexadecyloxy-5-(1,1,3,3-tetramethylbutyl)phenol 4-hexadecyloxy-3 obtained in Synthesis Example 2
-(1,1,3,3-tetramethylbutyl)phenylbenzenesulfonate 192.3g, dioxane
After mixing 192 ml of potassium hydroxide, 151.6 g of potassium hydroxide, and 96 ml of water, and heating under reflux for 1.5 hours under a nitrogen stream, the reaction solution was cooled by adding 384 ml of ethanol and 192 ml of water. Separately, 113.5 sulfanilic acid in 340 ml of 13% hydrochloric acid
A diazo solution prepared from 49.8 g of sodium nitrite and 49.8 g of sodium nitrite was added over 30 minutes at around 15° C., and further stirred at that temperature for 30 minutes. Then sodium hydrosulfite
171.9g was added at 40°C and stirred at 50°C for 1 hour.
660 ml of ethyl acetate was added to the reaction solution to separate the layers, and 46.5 ml of acetic anhydride was added to the upper layer at 5° C. or below. The reaction solution was mixed with 8% sodium bicarbonate aqueous solution 1.3 and 5%
Each was washed with 650 ml of brine, ethyl acetate was distilled off under reduced pressure, and 840 ml of methanol was added. After cooling to 0°C, the precipitated crystals were collected and 2-acetylamino-4-hexadecyloxy-5-(1.1.
3,3-tetramethylbutyl)phenol 96.6
I got g. mp76-78℃ Synthesis example 4 2-amino-4-hexadecyloxy-5-
Synthesis of (1,1,3,3-tetramethylbutyl)phenol 2-acetylamino-4-hexadecyloxy-5-(1,1,3,3-tetramethylbutyl)phenol obtained in Synthesis Example 3 92.3g, ethanol
320 ml and 235 ml of hydrochloric acid were mixed and heated under reflux for 5 hours. After cooling, add 320 ml of water and 320 ml of hexane to separate the layers, and add 210 ml of p-toluenesulfonic acid to the upper layer.
g, and 833 ml of methanol were added to separate the layers. water in the lower layer
800 ml and 320 ml of ethyl acetate were added to separate the layers, and 400 ml of ethyl acetate and 360 ml of acetonitrile were added to the upper layer. 0℃
After cooling to
78.0 g of p-toluenesulfonate of (3-tetramethylbutyl)phenol was obtained. mp165-170℃ (decomposition) Synthesis example 5 Synthesis of 2-nitro-5-(1,1,3,3-tetramethylbutyl)-hydroquinone diacetate Add 10ml of sulfuric acid to 400ml of acetic anhydride, then heat at 10℃
Below, 222 g of 1,1,3,3-tetramethylbutylhydroquinone was added little by little. After stirring for 30 minutes, 52.3 ml of fuming nitric acid was added dropwise over 3 hours at a temperature below 5°C. After further stirring for 1 hour, the mixture was poured into a mixture of 1 methanol and 200 g of ice to collect the precipitated crystals. Yield 86.7g, mp125-127℃ Synthesis Example 6 4-acetoxy-2-acetylamino-5-
Synthesis of (1,1,3,3-tetramethylbutyl)phenol 2-nitro-5-(1, synthesized in Synthesis Example 5)
1,3,3-tetramethylbutyl) hydroquinone diacetate 220g, ethanol 800ml, water 800ml
ml were mixed, and 60 ml of 29% ammonia water was added dropwise at 60°C. Then sodium hydrosulfite
544g was added little by little. After stirring for 15 minutes, acetic anhydride
256 ml was added dropwise at 30-40°C. Water 1 after cooling to 10℃
was added, the precipitated crystals were collected, and 4-acetoxy-2-acetylamino-5-(1, 1, 3, 3
137.6 g of -tetramethylbutyl)phenol were obtained. mp187～190℃ Synthesis example 7 5-hydroxy-2-methyl-6-(1・1・
Synthesis of 3,3-tetramethylbutyl)-benzoxazole 32.1 g of 4-acetoxy-2-acetylamino-5-(1,1,3,3-tetramethylbutyl)phenol synthesized in Synthesis Example 6, p-toluene 12.4 g of sulfonic acid and 80 ml of toluene were mixed and heated under reflux for 3 hours while removing generated water. After cooling, 28% sodium methylate methanol solution 19
After stirring for 10 minutes, hydrochloric acid was added to neutralize.
Next, the mixture was heated to remove water by azeotropy, and then cooled to collect precipitated crystals. The obtained crystals were washed with water to remove inorganic substances and dried to obtain 19.8 g of 5-hydroxy-2-methyl-6-(1.1.3.3-tetramethylbutyl)-benzoxazole. mp172−175℃ Synthesis example 8 5-hexadecyloxy-2-methyl-6-
Synthesis of (1,1,3,3-tetramethylbutyl)-benzoxazole 5-hydroxy-2-methyl-6-(1,1,3,3-tetramethylbutyl)benzoxazole obtained in Synthesis Example 7 88g was dissolved in 240ml of DMF, and 28.4g of sodium hydroxide was added at 70°C. Next, 133.7 g of 1-bromohexadecane was added dropwise, followed by stirring at 80°C for 30 minutes. Ethyl acetate after cooling
After adding 280 ml and 250 ml of water to separate the layers, and further washing the upper layer with water, ethyl acetate was distilled off under reduced pressure, and 250 ml of ethanol and 100 ml of acetonitrile were added to the residue. Ten
Cool to ℃, add 150 ml of acetonitrile, stir, collect the precipitated crystals, and give 5-hexadecyloxy-2-methyl-6-(1.1.
146 g of 3,3-tetramethylbutyl)benzoxazole was obtained. mp37～39℃ Synthesis Example 9 2-amino-4-hexadecyloxy-5-
Synthesis of (1,1,3,3-tetramethylbutyl)phenol 5-hexadecyloxy-2-methyl-6-(1,1,3,3-tetramethylbutyl)benzoxazole synthesized in Synthesis Example 8 A mixture of 181 g, 1 ethanol, and 930 ml of 36% hydrochloric acid was heated under reflux for 3 hours. After adding 1.2 g of ethanol to make a homogeneous solution, 352 g of p-toluenesulfonic acid was added.
After stirring for a while, it was cooled, the precipitated crystals were collected, and 2-amino-4-hexadecyloxy-5-(1,1,3,3-tetramethylbutyl) was obtained.
Phenol p-toluenesulfonate 208.7g
I got it. m.p165-170℃ (decomposition) Synthesis Example 10 Synthesis of dye-donating substance (1) 2-Amino- obtained in Synthesis Example 4 or Synthesis Example 9
4-hexadecyloxy-5-(1, 1, 3, 3
14.0 g of p-toluenesulfonate of (tetramethylbutyl)phenol was dissolved in 62 ml of N.N-dimethylacetamide under a nitrogen stream, and 6.6 g of pyridine was dissolved.
ml of 3-cyano-4-[3-chlorosulfonyl-4-(2-methoxyethoxy)phenylazo]-1-phenyl-5-pyrazolone 11.0
g was added. The mixture was stirred at room temperature for 1 hour and then at 50°C for 30 minutes. 132 ml of ethyl acetate and 88 ml of a 4% aqueous sodium hydrogen carbonate solution were added to the reaction solution to separate the layers, and the upper layer was further washed twice with 132 ml of a 4% aqueous sodium hydrogen carbonate solution. Next, add 265ml of methanol and 36% hydrochloric acid.
1.2 ml was added, cooled to 5°C, and precipitated crystals were collected. Yield 13.2g, mp116-118℃ Synthesis Example 11 Synthesis of dye-donating substance (10) 2-Amino-4 obtained in Synthesis Example 4 or Synthesis Example 9
-hexadecyloxy-5-(1,1,3,3-
15.0 g of p-toluenesulfonate (tetramethylbutyl)phenol was dissolved in 95 ml of N-N-dimethylacetamide under a nitrogen atmosphere, 11.5 ml of pyridine was added, and 4-[3-chlorosulfonyl-4-
(2-methoxyethoxy)phenylazo]-2-
18.5 g of (N.N-dimethylsulfayyl)-5-methylsulfonylamino-1-naphthol was added. After stirring at 30-35℃ for 1 hour, ethyl acetate 120
120 ml of water was added to separate the layers, and the upper layer was further washed with 120 ml of 5% saline. After ethyl acetate was distilled off under reduced pressure, 50 ml of ethanol and 50 ml of methanol were added to the residue, and the mixture was cooled to 0°C and the precipitated crystals were collected.
The obtained crystals were mixed with ethanol-methanol (2:
1) Purification by recrystallization from a mixed solvent. Yield 13.0
g, mp70-72℃ Synthesis Example 12 Synthesis of dye-donating substance (16) 2-Amino-4 obtained in Synthesis Example 4 or Synthesis Example 9
-hexadecyloxy-5-(1,1,3,3-
12.7 g of p-toluenesulfonate (tetramethylbutyl)phenol was dissolved in 75 ml of DMAc under a nitrogen stream. Add 4 ml of pyridine and add 5-(3-
Chlorosulfonylbenzenesulfonylamino)-
16 g of 4-(2-methylsulfonyl-4-nitrophenylazo)-1-naphthol was added and stirred at room temperature for 30 minutes. Then, after stirring at 70°C for 2 hours, 110 ml of acetone, 56 ml of water, and 100 ml of methanol were added in sequence to obtain an oily substance. This was purified by silica gel column chromatography (eluted with a mixed solvent of ethyl acetate and acetone (10:1)),
It was further recrystallized from ethanol. Yield 4.3gm.
p.216-219°C Other dye-providing substances could also be synthesized using almost the same method as in the above synthesis example. For example, the melting point of the dye-donating substance (6) is 170-175℃;
132-135℃ for (19), 72-76℃ for (21),
(22), the temperature was 154-158°C. The reducible dye-donating substance that releases the diffusible dye of the present invention can be used within a certain concentration range. Generally useful concentration ranges include organic silver salt oxidizing agent 1
per mole, from about 0.01 mole to about 4 mole of dye-donating material. Concentrations particularly useful in this invention range from about 0.03 moles to about 1 mole per mole of silver. In the present invention, a reducing agent can be used as necessary. The reducing agent in this case is a so-called auxiliary developing agent, which is oxidized by a silver salt oxidizing agent or silver halide, and its oxidized product has the ability to oxidize the reducing substrate R in the dye-donating substance. It is. Useful auxiliary developers include hydroquinone, alkyl-substituted hydroquinones such as tert-butylhydroquinone and 2,5-dimethylhydroquinone, catechols, pyrogallols, halogen-substituted hydroquinones such as chlorohydroquinone and dichlorohydroquinone, and alkyl-substituted hydroquinones such as methoxyhydroquinone. substituted hydroquinones,
There are polyhydroxybenzene derivatives such as methylhydroxynaphthalene. Furthermore, methyl gallate, ascorbic acid, ascorbic acid derivatives,
Hydroxylamines such as N.N'-di-(2-ethoxyethyl)hydroxylamine, pyrazolidones such as 1-phenyl-3-pyrazolidone, 4-methyl-4-hydroxymethyl-1-phenyl-3-pyrazolidone, Reductones and hydroxytetronic acids are useful. Auxiliary developers can be used over a certain concentration range. A useful concentration range is 0.01 times the mole to 20 times the organic silver salt oxidizing agent or silver halide, and a particularly useful concentration range is 0.1 times the mole to 4 times the mole. The amount of photosensitive silver halide used in the present invention is in the range of 0.005 mol to 5 mol, preferably in the range of 0.005 mol to 1.0 mol, per 1 mol of the organic silver salt oxidizing agent. Examples of silver halides include silver chloride, silver chlorobromide, silver chloroiodide, silver bromide, silver iodobromide, silver chloroiodobromide, and silver iodide. The grain size of silver halide is from 0.001 μm to 2
μm, preferably from 0.001 μm to 1 μm. The silver halide used in the present invention may be used as it is, but it may also be compounded with chemical sensitizers such as compounds such as sulfur, selenium, tellurium, etc., gold, platinum, palladium, rhodium, iridium, etc., or tin halide. Chemical sensitization may be achieved by the use of reducing agents such as or combinations thereof. For more information, see “The
Theory of the Photographic Process” 4th edition,
TH James, Chapter 5, pages 149-169. The organic silver salt oxidizing agent used in the present invention is a silver salt that is relatively stable to light, and is heated at a temperature of 80°C or higher, preferably 100°C in the presence of photosensitive silver halide.
When heated above, it reacts with the image-forming substance or a reducing agent coexisting with the image-forming substance if necessary to form a silver image. Examples of such organic silver salt oxidizing agents include the following. It is a silver salt of an organic compound having a carboxyl group, and representative examples include silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Examples of aliphatic carboxylic acids include silver salts of behenic acid, silver salts of stearic acid, silver salts of oleic acid, silver salts of lauric acid, silver salts of capric acid, silver salts of myristic acid, silver salts of palmitic acid, Silver salt of maleic acid, silver salt of fumaric acid, silver salt of tartaric acid, silver salt of furoic acid, silver salt of linoleic acid, silver salt of linoleic acid,
These include silver salts of oleic acid, silver salts of adipic acid, silver salts of sebacic acid, silver salts of succinic acid, silver salts of acetic acid, silver salts of butyric acid, and silver salts of camphoric acid. Furthermore, silver salts substituted with halogen atoms or hydroxyl groups are also effective. Silver salts of aromatic carboxylic acids and other carboxyl group-containing compounds include silver salts of benzoic acid;
Silver salt of 3,5-dihydroxybenzoic acid, silver salt of o-methylbenzoic acid, silver salt of m-methylbenzoic acid,
Silver salt of p-methylbenzoic acid, silver salt of 2,4-dichlorobenzoic acid, silver salt of acetamidobenzoic acid, p
-Silver salts of substituted benzoic acids such as silver salts of phenylbenzoic acid, silver salts of gallic acid, silver salts of tannic acid, silver salts of phthalic acid, silver salts of terephthalic acid, silver salts of salicylic acid, silver salts of phenyl acetic acid. , silver salt of pyromellitic acid, 3-carboxymethyl-4-methyl-4-thiazoline-2 described in U.S. Pat. No. 3,785,830
-silver salts such as thione, silver salts of aliphatic carboxylic acids having thioether groups as described in US Pat. No. 3,330,663, and the like. In addition, there are compounds having a mercapto group or a thione group, and silver salts of derivatives thereof. For example, 3-mercapto-4-phenyl-1.
Silver salt of 2,4-triazole, Silver salt of 2-mercaptobenzimidazole, 2-mercapto-5-
Silver salt of aminothiadiazole, silver salt of 2-mercaptobenzthiazole, silver salt of 2-(s-ethylglycolamido)benzthiazole, s-alkyl (alkyl group having 12 to 22 carbon atoms), thioglycolate, etc. Silver salts of dithiocarboxylic acids, silver salts of thioamides, such as silver salts of thioglycolic acid and silver salts of dithioacetic acid, as described in JP-A-48-28221, 5
-carboxy-1-methyl-2-phenyl-4-
Silver salt of thiopyridine, silver salt of mercaptotriazine, silver salt of 2-mercaptobenzoxazole,
Silver salt of mercaptooxadiazole, U.S. Patent No.
Silver salts described in specification No. 4123274, for example 1, 2,
Silver salt of 3-amino-5-benzylthio 1,2,4-triazole, which is a 4-mercaptotriazole derivative, 3- as described in U.S. Pat. No. 3,301,678
It is a silver salt of a thione compound such as a silver salt of (2carboxyethyl)-4-methyl-4-thiazoline-2thione. In addition, there are silver salts of compounds having imino groups. For example, silver salts of benzotriazole and its derivatives described in Japanese Patent Publications No. 44-30270 and No. 45-18416, silver salts of benzotriazole, silver salts of alkyl-substituted benzotriazoles such as methylbenzotriazole silver salt, 5-chlorobenzo Silver salts of halogen-substituted benzotriazoles such as silver salts of triazoles, silver salts of carboimidobenzotriazoles such as silver salts of butylcarboimidobenzotriazoles, 1,2,4-triazoles described in US Pat. No. 4,220,709, and Examples include silver salts of 1-H-tetrazole, silver salts of carbazole, silver salts of saccharin, and silver salts of imidazole and imidazole derivatives. Also research day closure VOl170,
Organometallic salts such as silver salts and copper stearate described in No. 17029, June 1978 are also organometallic salt oxidizing agents that can be used in the present invention. Although the thermal development process during heating of the present invention is not fully understood, it can be considered as follows. When a photosensitive material is irradiated with light, a latent image is formed on the photosensitive silver halide. Regarding this,
“The Theory of the
Photographic Process” 3rd Edition page 105~
It is described on page 148. By heating the light-sensitive material, a reducing agent, in the case of the present invention, a dye-donating substance, is combined with an organic silver salt oxidizing agent or a halogen silver and an organic The silver salt oxidizing agent is reduced to produce silver, which is itself oxidized. A nucleophilic reagent (dye release aid in the present invention) attacks this oxidized dye-donating substance, and the dye is released. The silver halide, the organic silver salt oxidizing agent, and the dye-donating substance may be present in the same layer or in separate adjacent layers. Although it is possible to prepare a coating solution by mixing separately formed silver halide and organic silver salt oxidizing agent before use, it is also effective to mix both and mix them in a ball mill for a long time. . Another effective method is to add a halogen-containing compound to the prepared organic silver salt oxidizing agent and form halogen silver with the silver from the organic silver salt oxidizing agent. For information on how to make these silver halides and organic silver salt oxidizing agents and how to mix both, please refer to Research Disclosure No. 17029, JP-A-50-32928, JP-A-51-42529, U.S. Patent No. 3,700,458, Japanese Patent Application Publication 1973-
No. 13224 and JP-A-50-17216. In the present invention, the total coating amount of photosensitive silver halide and organic silver salt oxidizing agent is 50 mg or more in terms of silver.
10g/ ^m2 is suitable. The photosensitive silver halide, organic silver salt oxidizing agent of the present invention is prepared in the following binder. A dye-providing substance is also dispersed in the binder described below. The binders used in the present invention can be contained alone or in combination. A hydrophilic binder can be used for this binder. Hydrophilic binders are typically transparent or translucent hydrophilic colloids, such as proteins such as gelatin, gelatin derivatives, cellulose derivatives, natural substances such as starch, polysaccharides such as gum arabic, and polyvinylpyrrolidone. , synthetic polymeric materials such as water-soluble polyvinyl compounds such as acrylamide polymers. Other synthetic polymeric compounds include dispersed vinyl compounds, which increase the dimensional stability of photographic materials, especially in the form of latexes. Various dye release aids can be used in the heat-developable color photosensitive material of the present invention. A dye release aid is a substance that can nucleophilically attack a dye-donating substance oxidized by an organic silver salt oxidizing agent and release a diffusible dye. A compound is used. Among these dye release aids, bases or base release agents are particularly useful because they not only promote dye release but also the redox reaction between the organic silver salt oxidizing agent and the dye-donating substance. . Examples of preferred bases include amines, including trialkylamines, hydroxylamines, aliphatic polyamines, N-alkyl substituted aromatic amines, N-hydroxyalkyl substituted aromatic amines and bis[ Examples include p-(dialkylamino)phenyl]methanes. U.S. Pat. No. 2,410,644 describes tetramethylammonium betaine iodide and diaminobutane dihydrochloride, and U.S. Pat. No. 3,506,444 describes organic compounds containing amino acids such as urea and 6-aminocaproic acid, which are useful. A base release agent releases a basic component upon heating. An example of a typical base release agent is British Patent No.
Described in No. 998949. Preferred base releasing agents are salts of carboxylic acids and organic bases; useful carboxylic acids include trichloroacetic acid, trifluoroacetic acid; useful bases include guanidine, piperidine, morpholine, p-toluidine, 2-picoline, and the like. Guanidine trichloroacetic acid, described in US Pat. No. 3,220,846, is particularly useful. Aldonamides described in JP-A No. 50-22625 are preferably used because they decompose at high temperatures to produce bases. A water-releasing compound is a compound that decomposes during thermal development to release water and replaces a compound with a vapor pressure of 10 ^-5 Torr or more at a temperature of 100 to 200°C. These compounds are particularly known for transfer printing of fibers, and are described in Japanese Patent Publication No. 88386/1986.
NH ₄ Fe(SO ₄ ) _{2.12H 2} O and the like are useful. These dye release aids can be used in a wide variety of ways. 1/100 to 10 times molar ratio to silver,
In particular, it is preferably used in a range of 1/20 to 2 times. Further, in the heat-developable color light-sensitive material of the present invention, a compound which activates development and simultaneously stabilizes the image can be used. Therein, U.S. Patent No. 3301678
Isothiuroniums represented by 2-hydroxyethyl isothiuronium and trichloroacetate described in No. 1 and 1 and 8 described in U.S. Patent No. 3,669,670
- Bisisothiuriums such as (3,6-dioxaoctane)bis(isothiuronium trifluoroacetate), thiol compounds described in West German Patent No. 2162714, 2-amino-2 described in U.S. Patent No. 4012260 -thiazolium trichloroacetate, 2-amino-5-bromoethyl-2-
Thiazolium compounds such as thiazolium trichloroacetate, bis(2-amino-2-thiazolium) methylene bis(sulfonylacetate), 2-amino-2 described in U.S. Pat. No. 4,060,420
Compounds having α-sulfonylacetate as an acidic moiety such as -thiazolium phenylsulfonylacetate, and compounds having 2-carboxycarboxamide as an acidic moiety as described in US Pat. No. 4,088,496 are preferably used. These compounds or mixtures can be used in a wide variety of ways. 1/100 molar ratio to silver
It is preferably used in the range of ~10 times, particularly 1/20 ~ 2 times. The heat-developable color photosensitive material of the present invention can contain a heat solvent. As used herein, a "thermal solvent" is a non-hydrolyzable organic material that is solid at ambient temperature but exhibits mixed melting points with other components at or below the heat treatment temperature used. Useful examples of the thermal solvent include compounds that can serve as solvents for developing agents, and compounds that are known to promote the physical development of silver salts using substances with a high dielectric constant. Useful thermal solvents include U.S. Pat.
Polyglycols described in No. 3347675, such as polyethylene glycol with an average molecular weight of 1,500 to 20,000;
Derivatives such as oleate esters of polyethylene oxide, beeswax, monostearin, -SO ₂
Compounds with a high dielectric constant having -, -CO- groups, such as acetamide, succinimide, ethyl carbamate, urea, methylsulfonamide, ethylene carbonate, polar substances described in US Pat. No. 3,667,959, lactone of 4-hydroxybutanoic acid,
Methylsulfinylmethane, tetrahydrothiophene-1,1-dioxide, 1,10-decanediol described in Research Disclosure Magazine, December 1976 issue, pages 26-28, methyl anisate, biphenyl suberate, etc. are preferred. used. In the case of the present invention, the dye-providing substance is colored, and although it is not so necessary to incorporate an irradiation or anti-halation substance or dye into the light-sensitive material, in order to further improve the sharpness, −3692 publication, U.S. Patent No. 3253921,
Filter dyes and absorbent substances described in specifications such as No. 2527583 and No. 2956879 can be contained. Preferably, these dyes are thermally decolorizable, such as those described in U.S. Patent No. 3769019, U.S. Pat.
Preference is given to dyes such as those described in No. The photosensitive material according to the present invention may contain various additives known as heat-developable photosensitive materials and layers below the photosensitive layer, such as an antistatic layer, a conductive layer, a protective layer,
It can contain an intermediate layer, an AH layer, a release layer, etc. For various additives, “Research
Disclosure"Vel170 June Additives listed in No. 17029 of 1978 such as plasticizers, sharpness improving dyes, AH dyes, sensitizing dyes, matting agents, surfactants, fluorescent whitening agents, anti-fading As with the heat-developable photosensitive layer of the present invention, protective layers, intermediate layers, undercoat layers, back layers, and other layers may also include
Prepare each coating solution and apply the dipping method, air knife method, curtain coating method or U.S. Patent No. 3681294.
A light-sensitive material can be prepared by sequentially coating a support onto a support using various coating methods such as the hopper coating method described in the specification and drying. Furthermore, if desired, two or more layers can be applied simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095. Various exposure means can be used for the heat-developable photosensitive material according to the present invention. The latent image is obtained by imagewise exposure to radiation, including visible light. In general, light sources used for ordinary color printing, such as tungsten lamps, mercury lamps, halogen lamps such as iodine lamps, xenon lamps, laser light sources, CRT light sources, fluorescent tubes, light emitting diodes, etc. can be used as light sources. The original drawing may be a line image such as a technical drawing, or a photographic image with gradation. It is also possible to photograph images of people and landscapes using a camera. The printing from the original drawing may be carried out by contact printing, reflection printing, or enlargement printing by overlapping the original drawing. In addition, images taken with video cameras and image information sent from television stations can be directly processed.
It is also possible to output the image to a CRT or FOT, form the image on a heat-developable material using a contact lens or a lens, and then print it. Furthermore, LEDs (light emitting diodes), which have recently seen great progress, are being used as exposure means or display means in various devices. It is difficult to create an LED that effectively emits blue light. In this case, to reproduce a color image, three LEDs emit green, red, and infrared light.
The seeds may be designed so that the parts of the photosensitive material that are sensitive to these lights emit yellow, magenta, and cyan dyes, respectively. That is, the green-sensitive portion (layer) may contain a yellow dye-providing substance, the red-sensitive portion (layer) may contain a magenta dye-providing substance, and the infrared-sensitive portion (layer) may contain a cyan dye-providing substance. Other combinations are also possible as required. In addition to the above method of directly attaching or projecting the original image, the original image illuminated by a light source can be
After reading the information using a light-receiving element such as a CCD and storing it in the memory of a computer, processing this information as necessary and performing so-called image processing, this image information is reproduced on a CRT and used as an image-like light source. There is also a method of directly emitting light from three types of LEDs for exposure based on the processed information. After exposure of a heat-developable color photographic element, the resulting latent image is e.g.
Development can be accomplished by heating the element in its entirety at a moderately elevated temperature, such as for 300 seconds. As long as the temperature is within the above range, either high or low temperatures can be used by increasing or shortening the heating time. A temperature range of about 110°C to about 160°C is particularly useful. The heating means may be simply a hot plate, an iron, a hot roller or the like. In the present invention, a preferred specific method for forming a color image by thermal development is thermal diffusion transfer of a hydrophilic diffusible dye. For this purpose, a heat-developable color photosensitive material has a photosensitive layer (2) on a support that contains at least silver halide, an organic silver salt oxidizing agent, a dye donating substance which is also a reducing agent, and a hydrophilic binder; It is composed of an image-receiving layer ( ) capable of receiving a hydrophilic and diffusible dye formed in layers. The dye-releasing aid may be included in the photosensitive layer () or the image-receiving layer (). Alternatively, a separate means for applying the dye release aid (e.g., a breakable pot containing the dye release aid, a roller impregnated with the dye release aid, or a device for spraying a liquid containing the dye release aid) may be provided. It's okay. The above-mentioned photosensitive layer () and image-receiving layer () may be formed on the same support, or may be formed on separate supports. The image receiving layer () is
It can also be peeled off from the photosensitive layer. For example, after imagewise exposure of a heat-developable color photosensitive material, uniform heat development can be carried out, and then the image-receiving layer can be peeled off. In another specific method, after imagewise exposure, an image-receiving layer (2) may be superimposed on the photosensitive layer (2), which has been uniformly heat-developed, and the dye may be transferred at a temperature lower than the development temperature. In this case, "lower temperature than the development temperature" includes room temperature, and preferably refers to a temperature from room temperature to about 40° C. lower than the heat development temperature. For example, this corresponds to a heat development temperature of 120°C and a transfer temperature of 80°C. There is also a method in which only the photosensitive layer (2) is imagewise exposed, and then the image-receiving layer (2) is superimposed and uniformly developed by heating. The image-receiving layer () contains a dye mordant, and various mordants can be used in the present invention, and a useful mordant can be selected depending on the physical properties of the dye, transfer conditions, other components contained in the photographic material, etc. can. The mordant used in the present invention is a high molecular weight polymeric mordant. The polymer mordants used in the present invention are polymers containing secondary and tertiary amino groups, polymers having nitrogen-containing heterocyclic moieties, polymers containing these quaternary cation groups, etc., and have a molecular weight of 5,000 to 200,000, particularly 10,000 to 10,000. 50,000. For example, US Patent No. 2548564, US Patent No. 2484430, US Patent No.
Vinylpyridine polymers and vinylpyridinium cationic polymers disclosed in U.S. Patent Nos. 3148061 and 3756814;
Polymer mordants capable of crosslinking with gelatin etc. disclosed in US Pat. No. 3859096, US Pat.
No. 2798063, Japanese Unexamined Patent Publication No. 115228, No. 54-
Aqueous sol-type mordant disclosed in No. 145529, No. 54-126027, etc.; Water-insoluble mordant disclosed in U.S. Pat. No. 3,898,088; U.S. patent
A reactive mordant capable of forming a covalent bond with the dye disclosed in the specification of No. 4168976 (Japanese Unexamined Patent Publication No. 54-137333); furthermore, US Pat. No. 3709690, US Pat. Same No. 3557066,
No. 3271147, No. 3271148, Japanese Patent Application Publication No. 1971-
No. 71332, No. 53-30328, No. 52-155528, No. 53
Examples include mordants disclosed in Japanese Patent No. 125 and No. 53-1024. Other mordants described in US Pat. No. 2,675,316 and US Pat. No. 2,882,156 can also be mentioned. Among these mordants, those that are difficult to move from the mordant layer to other layers within the photosensitive layer are preferred, for example,
Preferably used are those that crosslink with the matrix such as gelatin, water-insoluble mordants, and aqueous sol (or latex dispersion) type mordants. Particularly preferred polymer mordants are shown below. (1) Groups that have a quaternary ammonium group and can be covalently bonded to gelatin (for example, aldehyde groups, chloroalkanoyl groups, chloroalkyl groups, vinylsulfonyl groups, pyridinium propionyl groups,
Polymers having vinylcarbonyl groups, alkylsulfonoxy groups, etc.) For example, (2) A reaction product of a copolymer consisting of a repeating unit of a monomer represented by the following general formula and a repeating unit of another ethylenically unsaturated monomer, and a crosslinking agent (eg, bisalkanesulfonate, bisarenesulfonate).

[Formula] R ₂₁ : H, alkyl group R ₂₂ : H, alkyl group, aryl group Q: divalent group R ₂₃ , R ₂₄ , R ₂₅ : alkyl group, aryl group, or at least 2 of R ₂₃ to _{R 25} may be combined to form a heterocycle. X: anion (the above alkyl groups and aryl groups include substituted ones) (3) Polymer represented by the following general formula -(A)- _x -(B)- _y

[Formula] x: about 0.25 to about 5 mol% y: about 0 to about 90 mol% z: about 10 to about 99 mol% A: Monomer having at least two ethylenically unsaturated bonds B: Copolymerizable ethylene Sexually unsaturated monomer Q: N, P R ₃₁ , R ₃₂ , R ₃₃ : an alkyl group, a cyclic hydrocarbon group, or at least two of R ₃₁ to _{R 33} may be combined to form a ring. (These groups and rings may be substituted.) (4) Copolymer consisting of (a), (b) and (c) (a)

[Formula] or

[Formula] 3
Water-insoluble polymer having more than R ₄₁ , R ₄₂ , R ₄₃ : Each represents an alkyl group, and the total number of carbon atoms in R ₄₁ to _{R 43} is 12 or more. (The alkyl group may be substituted.) X: Anion (6) Polymer having repeating units represented by (d) and/or (e) below (d) (e) Z: atoms necessary to complete the nitrogen-containing heterocycle R ₅₁ and R ₅₂ : H, alkyl, hydroxyalkyl, ^aralkyl It can be done. For example, it is also possible to use gelatin produced using different gelatin manufacturing methods, such as coal-processed gelatin or acid-treated gelatin, or gelatin obtained by chemically modifying the resulting gelatin, such as phthalation or sulfonylation. . Moreover, if necessary, it can be used after being subjected to desalting treatment. The mixing ratio of the polymer mordant and gelatin of the present invention and the coating amount of the polymer mordant can be easily determined by those skilled in the art depending on the amount of dye to be mordanted, the type and composition of the polymer mordant, and the image forming process to be used. However, the mordant/gelatin ratio is 20/80 to 80/20 (weight ratio), and the amount of mordant applied is 0.5
Preferably it is used at ~8 g/ ^m2 . The image receiving layer ( ) may have a white reflective layer. For example, on top of a mordant layer on a transparent support,
A layer of titanium dioxide dispersed in gelatin can also be applied. The titanium dioxide layer forms a white opaque layer, and by viewing the transferred color image from the transparent support side, a reflective color image can be obtained. A typical image-receiving material for diffusion transfer is obtained by coating a polymer containing an ammonium salt mixed with gelatin on a transparent support. A transfer solvent can be used to transfer the dye from the photosensitive layer to the image-receiving layer. As the transfer solvent, water and a basic aqueous solution containing sodium chloride, potassium hydroxide, and an inorganic alkali metal salt are used. Also used are low-boiling solvents such as methanol, N·N-dimethylformamide, acetone, and diisobutyl ketone, and mixed solutions of these low-boiling solvents and water or basic aqueous solutions. The transfer solvent may be used by moistening the image-receiving layer with the solvent, or may be incorporated into the material as crystal water or microcapsules. Example 1 6.5g of benzotriazole and 10g of gelatin in water
Dissolve in 1000ml. The solution is kept at 50°C and stirred. Next, add a solution of 8.5 g of silver nitrate dissolved in 100 ml of water.
Add to the above solution for a minute. Next, a solution of 1.2 g of potassium bromide dissolved in 50 ml of water is added over 2 minutes. The prepared emulsion is sedimented by pH adjustment to remove excess salt. Then the pH of the emulsion
Adjusted to 6.0. The yield was 200g. Next, we will describe how to make a gelatin dispersion of a dye-donating substance. 10g of dye-donating substance (10) as a surfactant,
Weigh 0.5 g of sodium succinate-2-ethyl-hexyl ester sulfonate and 20 g of tricresyl phosphate (TCP), add 30 ml of ethyl acetate, and heat to dissolve at about 60°C to form a homogeneous solution.
After stirring and mixing this solution and 100 g of a 10% solution of coal-treated ceratin,
Disperses at 10000RPM. This dispersion liquid is called a dispersion of a dye-providing substance. Next, a method for preparing the photosensitive coating (No. 1) will be described. (a) 10 g of benzotriazole silver emulsion containing photosensitive silver bromide (b) 3.5 g of a dispersion of a dye-donating substance (c) A solution of 250 mg of guanidine trichloroacetic acid dissolved in 2.5 ml of ethanol (a) to (c) ) were mixed and heated to melt, and then coated on a polyethylene terephthalate film with a thickness of 180 μm to a wet film thickness of 60 μm. After drying this coated sample, it was imagewise exposed for 10 seconds at 2000 lux using a tungsten bulb. Thereafter, it was heated uniformly for 30 seconds on a heat block heated to 150°C. Next, a method for forming an image-receiving material having an image-receiving layer will be described. 10 g of poly(methyl acrylate-co-N・N・N-trimethyl-N-vinylbenzylammonium chloride) (ratio of methyl acrylate and vinylbenzylammonium chloride is 1:1)
100g 10% lime processed gelatin dissolved in 200ml water
was mixed evenly. This mixed solution was uniformly applied onto a polyethylene terephthalate film to a wet film thickness of 20 μm. After drying, this sample was used as an image receiving material. After the image-receiving material was immersed in water, the above-mentioned heated photosensitive material was stacked on top of each other so that the film surfaces were in contact with each other. After 30 seconds, the image-receiving material was peeled off from the light-sensitive material, leaving a negative magenta dye on the image-receiving material. The density of this negative image was measured using a Macbeth transmission densitometer (TD-504).
When measured using , the maximum density for green light was 2.30 and the minimum was 0.08. In addition, the gradation of the sensitometric curve is a straight line, with an exposure difference of 10
The difference in concentration was 1.35. Example 2 Comparative Sample The same operation as in Example 1 was carried out except that 10 g of the following A and B were used as comparative compounds other than the present invention in place of the dye-donating substance (10), and photosensitive material No.
2. I made No.3. Comparative compound A Comparative compound B Using the above photosensitive materials No. 2 and No. 3, the same processing as in Example 1 was carried out to obtain a negative color image on the image-receiving material. The measured concentration values for each are shown in the table below.

[Table] From the above results, it was found that the compound of the present invention gave a high concentration but caused only a slight fog. Example 3 About the yellow dye-donating substance Completely the same as Example 1 except that (1), (2), and (3) were used instead of the dye-donating substance (10), and 10 g of C having the following structure was used as a comparative compound. After various treatments and operations, we obtained the results shown in the table below. Comparative compound C

[Table] (Not according to the present invention) It can be seen that the composition of the present invention has a low fog density and a relatively high maximum density. Example 4 Regarding cyan dye-donating substances Except for using dye-donating substances 16, 17, 18 and 10 g of compounds D and E having the following structures as comparative compounds,
The same treatments and operations as in Example 1 were performed to obtain the results shown in the table below. Comparative compound D Comparative compound E Dye-donating substance No. Maximum density Minimum density 16 2.10 0.12 17 1.90 0.10 18 2.00 0.10 For comparison (not according to the invention) D 1.75 0.14 〃 E 2.10 0.20 From these results, the substance of the present invention has less fogging than a higher concentration. It was found that there were few Example 5 40 g of gelatin and 26 g of KBr are dissolved in 3000 ml of water. The solution is kept at 50°C and stirred. Then silver nitrate
A solution of 34 g dissolved in 200 ml of water is added to the above solution over a period of 10 minutes. Then, a solution of 3.3 g of KI dissolved in 100 ml of water was added over 2 minutes. The pH of the silver iodobromide emulsion thus prepared is adjusted, and excess salt is removed by sedimentation. Thereafter, the pH was adjusted to 6.0 to obtain a silver iodobromide emulsion with a yield of 400 g. Next, we will describe how to make a gelatin dispersion of a dye-donating substance. 10g of dye-donating substance (10) as a surfactant,
Weigh 0.5 g of sodium succinate-2-ethyl-hexyl ester sulfonate and 20 g of tricresyl phosphate (TCP), add 30 ml of ethyl acetate, and heat to dissolve at about 60°C to form a homogeneous solution.
After stirring and mixing this solution and 100 g of a 10% solution of lime-treated gelatin, use a homogenizer for 10 minutes.
Disperses at 10000RPM. This dispersion liquid is called a dispersion of a dye-providing substance. Next, a method for preparing a photosensitive coating will be described. (a) Photosensitive silver iodobromide emulsion 5 g (b) Dispersion of dye-donating substance 3.5 g (c) A solution of 250 mg of guanidine trichloroacetic acid dissolved in 2.5 ml of ethanol Mix the above (a) to (c). After heating and melting, it was coated on a polyethylene terephthalate film with a thickness of 180 μm to a wet film thickness of 60 μm. After drying this coated sample, it was imagewise exposed for 10 seconds at 2000 lux using a tungsten bulb. Thereafter, it was heated uniformly for 30 seconds on a heat block heated to 150°C. The following operations were performed in exactly the same manner as in Example 1. The procedure was exactly the same as above, except that instead of using the dye-donating substance (10), (11) and (12) and 10 g each of compounds (F) and (G) with the following structures were used for comparison. I got results like this. Comparative compound F Comparative compound G

[Table] Preferred embodiments are as follows. 1. A mordant is used to transfer the dye released in a heat-developable color photosensitive material containing a photosensitive silver halide, an organic silver salt oxidizing agent, a hydrophilic binder, and a dye-donating substance represented by the formula () onto a support. Image forming method 2, characterized in that a color image is formed by transferring the image to an image-receiving material having the following properties: Diffusion transfer type heat development according to the claims, characterized in that a reducing agent for an organic silver salt oxidizing agent is included, if necessary. Color photosensitive material. 3. The image forming method according to item 1 above, characterized in that a dye release aid is included in the heat-developable color photosensitive material. 4. The image forming method according to item 1 above, characterized in that a dye-releasing aid is included in the image-receiving material. 5 In a heat-developable color photosensitive material containing a photosensitive silver halide, an organic silver salt oxidizing agent, a hydrophilic binder, and a dye-providing substance represented by the formula () on a support, a means for imparting a dye release aid. An image forming method comprising the steps of releasing a diffusible dye and transferring the dye to an image receiving material having a mordant to form a color image. 6 In the claims, embodiment 7 in which G is a hydroxyl group In the claims, embodiment 8 in which R is a dodecyl, tetradecyl, hexadecyl or octadecyl group In the claims, the Col moiety is a hydrophilic azo, azomethine, anthraquinone, A heat-developable color photosensitive material as claimed in the claims, characterized in that it is a naphthoquinone, styryl, nitro, quinoline, carbonyl, or phthalocyanine dye. 9. A heat-developable color photosensitive material, wherein the dye-releasing aid described in items 3, 4, and 5 above is a base, a base-releasing agent, or a water-releasing compound. 10. A heat-developable color photosensitive material, wherein the organic silver salt oxidizing agent according to the claims is a silver salt of a carboxylic acid derivative or a nitrogen-containing heterocyclic compound. 11. A heat-developable color photosensitive material, wherein the hydrophilic binder as claimed in the claims is gelatin or a gelatin derivative. 12. The image forming method according to item 1, characterized in that the released diffusible dye is transferred to an image-receiving material using water or a basic aqueous solution. 13. A heat-developable color photosensitive material, wherein the organic silver salt oxidizing agent according to item 10 is a silver salt of a nitrogen-containing heterocyclic compound.

Claims (1)

[Scope of Claims] 1. A heat-developable color photosensitive material containing a photosensitive silver halide, an organic silver salt oxidizing agent, a hydrophilic binder, and a dye-providing substance represented by the following general formula () on a support. (Here, G is a hydroxyl group or a group that provides a hydroxyl group by hydrolysis; Col is a dye or a group that provides a dye; R is an alkyl or aromatic group.