JPH0333743A - Heat developable color photosensitive material - Google Patents

Abstract

PURPOSE:To develop high-density color images in a short time even at a relatively low temp. by incorporating a capsule material contg. a photosensitive silver halide, dye stuff donative material, binder and the hydrophobic salt of a color developer as core material on a base. CONSTITUTION:This photosensitive material contains the capsule material which consists of at least the photosensitive silver halide, the dye stuff donative material, the binder and the hydrophobic salt of the color developer as the core material and has the water insoluble polymer wall on the base. The capsule material is preferably incorporated in the form of a microcapsule into the developable photosensitive material. The high-density color images are obtd. by the development of the relatively low temp. in a short period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat-developable color photosensitive material in which a dye image is formed by heat development. The present invention can be suitably embodied, for example, as a heat-developable color photosensitive material that forms a color image by diffusion-transferring a dye.

[Background of the invention]

A photosensitive material (thermally developable photosensitive material) that can easily and quickly form an image by carrying out a dry process using heat in the development process is well known. Publication No. 43-4924, pages 553 to 555 of "Fundamentals of Photographic Engineering" Silver Salt Photography m (published by Corona Publishing in 1879), and Research Disclosure magazine June 1978 issue, pages 9 to 15 (RD-170).
29) etc.

There are two types of heat-developable photosensitive materials: those that produce black-and-white images and those that produce color images. In recent years, in particular, attempts have been made to develop heat-developable color photosensitive materials that produce color images using various dye-providing substances.

There are various methods for heat-developable color photosensitive materials, such as a method in which a color image is obtained by releasing or forming a diffusible dye through heat development and then transferring the dye (
Although this method (hereinafter referred to as a transfer method) requires an image receiving member for transfer, it is superior in terms of image stability and clarity, and processing simplicity and speed. This transfer method heat-developable color photosensitive material and image forming method are described, for example, in JP-A-50-12431, JP-A-59-159159, and JP-A-5.
No. 9-181345, No. 59-229556, No. 60
-2950 No. 6], -52643 No. 61-61
No. 158, No. 61-61157, No. 59-18055
No. 0, No. 61-132952, No. 61-139842
No. 4,595,652, U.S. Patent No. 4.
It is described in the specifications of No. 590.154 and No. 4,584.267.

In heat-developable color photosensitive materials, especially those that use a coupling reaction to form or release dyes (coupling method), water etc. are supplied externally to the photosensitive material to produce high-density, low-fog images. It is excellent in that it can be obtained without any need for heat.

However, in the coupling method, it is necessary to use a color developing agent (for example, a p-phenylenediamine derivative or a p-aminophenol derivative) as a reducing agent, and adding them to a light-sensitive material can have a serious effect on the storage stability of the light-sensitive material and the staining of images. have a negative impact.

As a means to solve this problem, a method has been proposed in which a color developing agent is used in the form of its precursor.
No. 540, No. 60-128438, No. 60-1284
No. 39, No. 60-181742, No. 62-13125
No. 2, No. 62-131252, No. 62-131256
It is stated in each specification of the issue.

In particular, N-(p-
N,N-dialkylami)) Phenylsulfamates are excellent color developers in terms of storage stability and deprecursor properties, and further improvements are needed for development at lower and shorter temperatures. desired.

In addition, in order to improve the storage stability of the photosensitive material or to improve various physical and chemical properties of the photosensitive material, it is preferable to locally add a color developer to a specific layer of the photosensitive material. However, the color developing agents used in known heat-developable color photosensitive materials are difficult to localize because they diffuse during production or storage.

[Purpose of the invention]

An object of the present invention is to solve the problems of the prior art.

The object of the present invention is to be able to obtain high-density color images in a short time and at relatively low temperatures, to have good storage stability, to have little staining on white backgrounds, and to be clear. An object of the present invention is to provide a heat-developable color photosensitive material from which color images can be obtained.

[Structure of the invention]

As a result of intensive research to achieve the above object, the inventors of the present invention have discovered that a heat-resistant film containing a capsule material having a hydrophobic salt of a photosensitive silver halide, a dye-providing material, a binder, and a color developer as a core material on a support is provided. It has been found that the above objects of the present invention can be achieved by a developable color photosensitive material.

The present invention will be explained in detail below. The heat-developable photosensitive material of the present invention contains a capsule material (hereinafter referred to as "capsule material of the present invention") having a hydrophobic salt of a color developer (hereinafter also referred to as "compound of the present invention") as a core material. The capsule material of the present invention is such that the core material containing at least the compound of the present invention is covered with a material constituting a water-insoluble polymer wall (such material may be abbreviated as (referred to as "wall material"), which is capsule-shaped. The capsule material of the present invention has a microcapsule shape,
It is preferably contained in the heat-developable photosensitive material of the present invention in the form of so-called microcapsules.

Further, the capsule material of the present invention may be contained in any photographic constituent layer of the light-sensitive material. It is believed that the compound of the present invention is released from the polymer wall mainly during thermal development, and that the compound of the present invention acts upon heat. , can exhibit such an effect.

Preferably, the capsule material of the present invention is included in the photosensitive layer.

In the capsule material of the present invention, the core material of the compound of the present invention is usually confined by the wall material, but the core material can be released during thermal development. As a result,
During thermal development, the compound of the present invention can fully exhibit its function, but until then, the compound of the present invention is isolated by the wall material, so the photosensitive material does not become sticky, and the storage of the photosensitive material (over time) is prevented. ), the deterioration of storage stability such as a decrease in sensitivity and an increase in fog is improved.

The hydrophobic salt of the color developer which is the core material of the capsule material of the present invention will be explained. This hydrophobic salt is preferably a salt composed of a color developer and an organic acid.

The color developing agent constituting the core material of the capsule material of the present invention is preferably a color developing agent having an amino group,
Further, p-phenylenediamine derivatives or p-aminophenol derivatives are preferable, particularly those represented by the following general formula (1)
Compounds represented by are preferred.

In the formula, R1 represents an optionally substituted alkyl group (e.g., methyl group, ethyl group), an optionally substituted alkoxy group (e.g., methoxy group, ethoxy group), or a hydrogen atom, and each group has Examples of substituents that may be used include alkoxy groups (e.g. methoxy group, ethoxy group), alkylsulfonylamino groups (e.g. methanesulfonylamino group),
or halogen atoms (e.g. chlorine atom, fluorine atom)
is preferred.

Rt and Rs may be the same or different, and each may be an optionally substituted alkyl group (preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n- (propyl group, n-butyl group), and substituents that Rt and R3 may have include alkoxy groups (e.g. methoxy group, ethoxy group), alkyl groups sulfonylamino group (e.g. methanesulfonylamino group) A hydroxy group or a halogen atom (chloro atom, fluorine atom) can be mentioned.

The hydrophobic salt of the developer is preferably a salt with an organic acid, and in this case, the organic acid that forms a salt with the developer is an organic acid that can form a hydrophobic salt with the color developing agent. For example, organic acids such as organic sulfonic acids, organic phosphoric acids, carboxylic acids, sulfinic acids, and the like, and organic acids having two or more carbon atoms can be preferably used. Also, JP-A-56-16133
Organic acids described in Japanese Patent No. 5659232 and Japanese Patent No. 56-67842 can also be used.

A particularly preferably used acid is a boron-based compound represented by the following general formula (2).

General formula (2) In the formula, R4, R3, Rh and R7 each represent an alkyl group, an alkenyl group, a cycloalkyl group, an allyl group, a phenyl group or a cyano group, and each of the groups other than the cyano group has a substituent. You can.

The compound of the present invention has a solubility in water at 25°C of 1
It is preferable that it is less than wt%. In order to control the solubility in water in this manner, the number of carbon atoms contained in the organic acid is preferably 12 or more.

Preferred specific examples of the compounds of the present invention are listed below. However, as a matter of course, this is not limited to the following examples: , 1;ry /, :,,
More details below; Shisan\Il- (1) (2) (3) (4) (5) (6) (7) (8) (]1) (12) (15) (18) (19) (22) (23) (25) (26) (27) (28) (29) (30) The following margins The compounds of the present invention can be synthesized as follows. When synthesized from a color developing agent having an amino group and an organic acid, a water-soluble salt (for example, hydrochloride, sulfuric acid salt, etc.) of a color developing agent having an amino group (for example, p-phenylenediamine derivative, p-aminophenol derivative) An aqueous solution of a water-soluble salt of an organic acid (e.g., an alkali metal salt, an ammonium salt) is mixed with an aqueous solution of a water-soluble salt of an organic acid (e.g., an alkali metal salt, an ammonium salt), thereby forming a poorly water-soluble salt of the compound of the present invention. By precipitating
Easily synthesized.

Examples of synthesis of the compounds of the present invention are shown below.

Synthesis Example: Synthesis of Exemplified Compound-1 200% of an aqueous solution containing 11g of sulfate of 2-methyl-4-(N,N-dimethylamino)aniline and 2g of sodium ascorbate, and 200% of an aqueous solution containing 15g of sodium tetraphenylboronate. were simultaneously added dropwise into 200 ml of water under a nitrogen stream. After the completion of the addition, the mixture was further stirred for a while, and the precipitated white crystals were filtered off, and the crystals were washed with water and cold methanol.

The obtained crude crystals were recrystallized from methanol containing a small amount of L-ascorbic palmitate to obtain the desired product (exemplified compound -
1) 14g was obtained.

The compounds of the present invention may be contained alone in the capsule material, but they may also be contained in hydrophilic solvents such as ethyl acetate, butyl acetate, dibutyphthalate, dioctyl phthalate, tricresyl phosphate, etc., or in other hydrophobic substances, such as It may be contained together with photographic additives such as dye-providing substances, antioxidants (eg, hydroquinone derivatives, ascorbic acid derivatives), antifoggants, development accelerators, and the like.

The capsule material of the invention has a water-insoluble polymer wall.

The capsule material containing the compound of the present invention as a core material may have the function of transmitting the core material through the capsule wall during thermal development or releasing the core material by melting or breaking the capsule wall by heating. Any polymer wall having such a function can be used.

The above-mentioned functions in the capsule material can be provided, for example, by the following method. That is, (a) Unexamined Japanese Patent Publication No. 1983
- A method of adding a thermally expandable substance to the core material as described in No. 119136; (b) A widely known method of using a thermoplastic or thermofusible material as a wall material. (c) A method of coating a porous outer wall with a liquid crystal material and displacing and releasing it by heat, as described in Okahata, "Fine Chemicals", Vol. 13, p. 27 (1984).

Specific examples of each of (a), (b), and (c) include the following compounds.

In case (a), as a wall material, as a water-insoluble polymer,
Cellulose, gelatin, gum arabic, acrylic resin,
Styrene resin, polyester resin, urethane resin, polyamide resin, epoxy resin, vinyl alcohol resin, etc. can be used.

In addition, thermally expandable substances added to the core material include compounds that decompose with heat and release nitrogen such as abbisisobutyronitrile and miazobisisovaleronitrile, nitro-containing compounds such as trinitrotoluene and picric acid, Volatile substances such as isobutylene and butane can be used.

In the case of (b), a water-insoluble polymer that melts at a temperature below the development temperature can be used as the wall material. For example, styrene resins such as polystyrene and polychlorostyrene, acrylic resins such as polymethyl methacrylate, polymethyl acrylate, polyethyl acrylate, polybutyl methacrylate, thermoplastic resins such as polyester resins, polyethylene, polyoxyethylene, higher fatty acid amides, higher grade Waxes such as fatty acid ester, carnauba wax, and wax can be used.

In the case of (c), examples of the water-insoluble polymer forming the porous outer wall include nylon obtained by interfacial polymerization, and examples of the liquid crystal material include the following bilayer membranes.

(iv) n In addition, the capsule material of the present invention preferably has a particle size of 0.
It is 5 to 50 μm, more preferably 1.0 to 10 μm.

Various encapsulation methods can be applied to produce a capsule material containing the compound of the present invention in the core material.

For example, U.S. Patent No. 2.800.457;
No. 0.458, No. 3.287.154, No. 3,418
．． No. 250, No. 3,660.304, No. 3,726.
No. 804, No. 3,796.669, British Patent No. 990
, No. 443 and JP-A-59-113434, and one of the microcapsule manufacturing methods described on pages 71 to 36 of Latest Microencapsulation Technology (published by Sogo Technological Center) can be used.

In the present invention, a method for manufacturing microcapsules having an average particle size of 5 μm or less is particularly desirable, but such manufacturing methods are generally classified into the following two types.

One is interfacial polymerization using emulsification such as electroemulsification.
This is so-called micelle polymerization, in which polymerization is performed after saccharification. When encapsulating the core material containing the compound of the present invention,
It is not possible to use both methods for all core materials. That is, the interfacial polymerization method cannot be applied to core materials that easily react with acid chlorides, and the micelle polymerization method cannot use core materials that prevent radical reactions.

Methods for producing such microcapsules include G. Bielenbach and B.B.S.
rrenback, P.P., 5petser), Journal of Pharmaceutical Sciences (
Journal of Pharmaceutical
5sciences), 65(12)P, 1763-1
766 (1976), B. Zulkens, M. Roland, N. Troets, B. Spiesser (P.
Tulkens, M., Roland SA, Troue
t,,P.

5peiser), "F. E. B. S. Letters", 84 (2
) p, 5peise as described in p, 323 (1977)
Micelle polymerization method using r, etc., Watanabe, Higashitsuji, 6
tanabe, ni, former gashitsuji, K, N
isN15hiza “Journal of Colloids and Ink-Face Science J”
al of Co11oid and Interfa
ce 5science), 64(2)p, 278(1
978) 0 River, prodigal (M, ^rakawa, T, K
ondo), “Canadian Journal of Physiology and Pharmacology J”
ianJournal of Physiology
and Pharmacolog31)+58(2)p
, 183 (1980), etc. are advantageously used.

Furthermore, when a salt of an organic acid is used as the compound of the present invention in the production of microcapsules, that is, in the emulsification or micellization step and/or the polymerization step, water-soluble salts of the organic acid (for example, alkali metal salts, ammonium It is preferable to add salt). At this time, the amount of the organic acid salt added is preferably 0.01 to 2 per mole of the compound of the present invention.
0 mol, more preferably 0.03 to 5 mol.

The capsule material of the present invention may be added to any layer of the heat-developable photosensitive material, for example, it can be contained in a photosensitive layer, or it can be contained in a non-photosensitive layer such as an undercoat layer, an intermediate layer, and a protective layer. You can also do it.

The amount added varies depending on the type of core substance used, that is, the compound of the present invention, and the form of the photosensitive material, but usually, the compound of the present invention is preferably added from 1.0 x 10-' to 1 M of the support of the photosensitive material to be added. 5.0 to 10-z mol, Yorima L <Ha1.0xlO-' ~ 5.0X10-'
-E le. The capsule materials of the present invention may be used alone or in combination of two or more.

Examples of dye-providing substances that can be used in the heat-developable color light-sensitive material of the present invention include the non-diffusible substances described in JP-A-62-44737, JP-A-62-129852, and JP-A-62-169158. For example, a leuco dye described in U.S. Pat. No. 475,441 or an azo dye used in the heat-developable dye bleaching method described in U.S. Pat. No. 4,235,957 is used as the dye-providing substance. However, it is more preferable to use a diffusible dye-providing substance that forms or releases a diffusible dye, and it is particularly preferable to use a compound that forms a diffusible dye by a cambling reaction.

Diffusible dye-providing substances that can be used in the present invention will be explained below. Diffusible dye-donor substances may be those capable of forming or releasing a diffusible dye as a function of the reduction reaction of the photosensitive silver halide and/or the organic silver salt used if necessary. Depending on their reaction form, they can be classified into negative-working dye-donating substances and positive-working dye-donating substances.

As a negative dye-donating substance, for example, U.S. Pat.
No. 63,079, No. 4,439.513, JP-A-59
-60434, 59-65839, 59-71
No. 046, No. 59-87450, No. 59-88730
Examples include reducible dye-releasing compounds described in the specifications of No. 59-123837, No. 59-124329, No. 59-165054, and No. 59-164055.

Other negative dye-providing substances include, for example, U.S. Pat.
, No. 474.867, JP-A-59-12431, No. 5
No. 9-48765, No. 59-174834, No. 59-
No. 776642, No. 59159159, No. 59-23
Examples include cambling dye-releasing compounds described in specifications such as No. 1040.

Another particularly preferred negative-tone dye-providing substance of the coupled dye-forming compound is one represented by the following general formula (a).

General formula (a) Cp − (J + = ---- 1,000 B) In the formula, Cp is an organic group ( J represents a divalent bonding group bonded to the active position that reacts with the oxidized form of the reducing agent, and B represents a ballast group. Here, the ballast group is a group that substantially prevents the dye-providing substance from diffusing during heat development processing, and includes groups that exhibit this effect depending on the nature of the molecule (such as a sulfo group),
Refers to groups that exhibit their effects depending on their size (groups with a large number of carbon atoms, etc.). The coupler residue represented by Cp preferably has a molecular weight of 700 or less, more preferably 500 or less, in order to improve the diffusibility of the dye formed.

The ballast group preferably has 8 or more carbon atoms, more preferably 12 or more carbon atoms, and even more preferably a group that is a polymer chain.

The coupling dye-forming compound having a group as a polymer chain is preferably one having a polymer chain having a repeating unit derived from a monomer represented by general formula (b) as the above group.

General formula (B) Cp-(-J-)-1,000Y-T-(Y-(L) In the formula, cp
, J has the same meaning as defined in general formula (a), and Y
represents an alkylene group, an arylene group, or an alkylene group, l represents O or 1, Z represents a divalent organic group,
L represents an ethylenically unsaturated group or a group having an ethylenically unsaturated group.

Specific examples of coupling dye-forming compounds represented by general formulas (a) and (b) include JP-A-59-124339
No. 59-181345, No. 60-2950, No. 6157943, No. 61-59336, etc.,
U.S. Pat. No. 4.631.251, U.S. Pat. No. 4,650.748
No. 4,656,124, particularly U.S. Pat. No. 4,656.124,
U.S. Patent Nos. 4,631.251 and 4,650,74
The polymer type dye-providing substances described in each specification of No. 8 are preferred.

As a positive dye-donating substance, for example, JP-A-59-
No. 55430, No. 59-165054, No. 59-15
No. 4445 No. 59-766954, No. 59-1166
No. 55, No. 59-124327, No. 59-15244
There are compounds described in publications such as No. 0.

These dye-providing substances may be used alone or in combination of two or more kinds. The amount used is not limited and depends on the type of dye-providing substance, whether it is used alone or in combination, and whether the photographic constituent layer of the light-sensitive material of the present invention is a single layer or a multilayer of two or more. For example, the amount used is 0.005 to 50 g per rrr, preferably 0.1 g = 10 g.

The dye-providing substance used in the present invention can be incorporated into the photographic constituent layer of the heat-developable light-sensitive material using any method. , tricresyl phosphate, etc.).
After emulsifying and dispersing or dissolving in an alkaline aqueous solution (for example, 10% aqueous sodium hydroxide solution, etc.), acid (
For example, it can be used after being neutralized with citric acid or nitric acid, or after being solidly dispersed in an aqueous solution of an appropriate polymer (eg, gelatin, polyvinyl butyral, polyvinyl pyrrolidone, etc.).

Next, the photosensitive silver halide used in the present invention will be described. Any silver halide can be used, and examples thereof include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, and silver iodobromide. The photosensitive silver halide can be prepared by any method commonly used in the photographic art.

Further, it is possible to use an emulsion containing grains having a multilayer structure in which the halogen U content of the grains is different on the surface and inside. For example, a silver halide emulsion having core/shell type silver halide grains in which the halogen composition changes stepwise or continuously can be used.

In addition, the shape of photosensitive silver halide is cubic, spherical, 8
It is possible to use materials that have a clear crystal habit, such as a hedron, dodecahedron, and tetradecahedron, or those that do not. This type of silver halide is described in JP-A-60-215948.

Also, for example, JP-A-58-111933, JP-A No. 58-1
No. 11934, No. 58-108526, Research Disclosure No. 22534, etc., each of which has two parallel crystal planes, and each of these crystal planes is larger than the other single crystal of this particle. It is also possible to use silver halide emulsions containing tabular silver halide grains having large area grains, the ratio of diameter to thickness of which is Aspect I/Non straw grains of 5:1 or more.

Further, in the present invention, a silver halide emulsion containing internal latent image type silver halide grains whose surfaces have not been fogged in advance can be used. For internal latent image type silver halide whose surface is not prefogged, for example, U.S. Pat.
．． 592.250, 3,206.313, 3.
No. 317,322, No. 3,51L622, No. 3.44
No. 7,927, No. 3,761.266, No. 3,703
, No. 584, No. 3,736,140, etc.

Internal latent image type silver halide grains whose surfaces are not fogged in advance are silver halide grains in which the sensitivity inside the grain is higher than the sensitivity on the surface of the silver halide grain, as described in each of the above specifications. be. Also, U.S. Patent No. 3,271.15
No. 7, No. 3,447,927 and No. 3,531.
Silver halide emulsions having silver halide grains incorporating polyvalent metal ions as described in U.S. Pat. No. 291, or silver halide containing dopants as described in U.S. Pat. Silver halide emulsion whose grain surface is weakly chemically sensitized, or JP-A-50-852
Silver halide emulsions comprising grains having a laminated structure as described in publications such as No. 4 and No. 50-38525, and other publications such as JP-A-52-156614 and JP-A-55-127.
Silver halide emulsions such as those described in No. 549 can be used.

The silver halide in the above-mentioned photosensitive emulsion may have coarse or fine grains, but the preferred grain size is about 0.005 μm to about 1.5 μm, more preferably about 0.005 μm to about 1.5 μm. .0μm to 0.5μm.

In the present invention, as another method for preparing photosensitive silver halide, a photosensitive root salt-forming component may be allowed to coexist with an organic silver salt described below to form photosensitive silver halide in a part of the organic silver salt.

These photosensitive silver halides and photosensitive root salt-forming fractions can be used in combination in various ways, and the amount used is preferably 0.001 g to 50 g per 1 d of support per layer. More preferably, it is 0.1 to 10 g.

The light-sensitive silver halide emulsion may be chemically sensitized by any method in the photographic art.

Further, the photosensitive silver halide emulsion used can be spectral sensitized using a known spectral sensitizing dye to impart sensitivity to blue, green, red, and near-infrared light.

Typical spectral sensitizing dyes that can be used include, for example, cyanine, merocyanine, complex (that is, trinuclear or tetranuclear) cyanine, holobola-cyanine,
Examples include styryl, hexcyanine, oxonol, and the like.

The preferred addition amount of these sensitizing dyes is lXl0- per mole of photosensitive silver halide or silver halide emulsion component.
The amount is 6 mol to 1 mol. More preferably, I Xl0-
'~lXl0-' mole.

The sensitizing dye may be added at any stage of the preparation of the silver halide emulsion. That is, it may be carried out at any time, such as when silver halide grains are formed, when soluble salts are removed, during chemical sensitization before the start of chemical sensitization, or after the end of chemical sensitization.

In the heat-developable photosensitive material of the present invention, it is preferable to use various organic silver salts, if necessary, for the purpose of increasing sensitivity and improving developability.

Examples of organic silver salts that can be used in the heat-developable photosensitive material of the present invention include JP-A Nos. 53-4921 and 49-5262.
No. 6, No. 52-141222, No. 53-36224, No. 53-37626, and No. 53-37610, as well as U.S. Patent No. 3,330.633, No. 3,794,496, Silver salts of long-chain aliphatic carboxylic acids and silver salts of carboxylic acids having heterocycles, such as silver behenate, α-( 1-Phenyltetrazolethio)silver acetate, etc., and Japanese Patent Publication No. 1982-26582, No. 45-
No. 12700, No. 45-18416, No. 45-221
No. 85, JP-A-52-137321, JP-A No. 58-118
No. 638, No. 5B-118639, U.S. Patent No. 4,1
There are silver salts of imino groups described in each publication of No. 23,274. Among the above organic silver salts, silver salts of imino groups are preferable. In particular, silver salts of benzotriazole derivatives, more preferably 5-methyl. Benzotriazole and its derivatives, sulfobenzotriazole and its derivatives, N-alkylsulfamoylbenzotriazole and its derivatives are preferred.

The organic silver salts used in the present invention may be used alone or in combination of two or more. Alternatively, the silver salt may be prepared in a suitable binder and used as is without isolation.
The isolated product may be used after being dispersed in a binder by an appropriate means. Dispersion means include, but are not limited to, ball mills, sand mills, colloid mills, vibration mills, and the like.

The amount of the organic silver salt used is generally preferably 0.01 to 500 moles, more preferably 0.1 to 100 moles per mole of photosensitive silver halide. More preferably 0.
It is 3 to 30 moles.

The heat-developable color photosensitive material of the present invention includes a reducing agent (a reducing agent precursor is also included in the reducing agent herein).
can be used. However, in the present invention, since the core substance of the capsule material acts as a reducing agent, it is not necessarily necessary to include a reducing agent, but using a reducing agent is one preferred embodiment. As the reducing agent, those commonly used in the field of photothermographic materials can be used.

Examples of reducing agents that can be used in the present invention include U.S. Pat. Nos. 3,531,286 and 3,761,27
No. 0, the specifications of No. 3,764.328, and RD (
Research Disclosure) Aim 12146, same N1
115108, same fish 15127 and JP-A-56-271
No. 32, U.S. Pat. No. 3,342,599. No. 3,719,492 Specifications, JP-A-53-1356
p- described in each publication such as No. 28 and No. 57-79035.
Phenyl acid and p-aminophenol type developing agents, phosphoramide phenol type, sulfonated aniline type developing agents, hydrazone type color developing agents and their precursors, or phenols, sulfonamide phenols, or polyhydroxy Benzenes, naphthols, hydroxybinaphthyls and methylene bisnaphthols, methylene bisphenols, ascorbic acid, 3-pyrazolidones, and pyrazolones can be used.

Further, the dye-donating substance may also serve as a reducing agent.

As a particularly preferable reducing agent, JP-A-56-146133
N-(p-
N.

N-dialkyl) phenylsulfonate is mentioned.

Two or more types of reducing agents may be used simultaneously.

The amount of the reducing agent used in the heat-developable photosensitive material of the present invention depends on the fi If of the photosensitive silver halide used, the type of organic acid silver salt, the type of other additives, etc., and is not necessarily constant. However, the amount is usually preferably from 0.01 to 1,500 mol, more preferably from 0.1 to 200 mol, per mol of photosensitive silver halide.

Binders that can be used in the heat-developable photosensitive material of the present invention include polyvinyl butyral, polyvinyl acetate,
These include synthetic or natural polymeric substances such as ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinyl pyrrolidone, gelatin, gelatin derivatives such as phthalated gelatin, cellulose derivatives, proteins, starch, and gum arabic. can be used alone or in combination of two or more. In particular, it is preferable to use gelatin or a derivative thereof together with a hydrophilic polymer such as polyvinylpyrrolidone or polyvinyl alcohol, and more preferably to use a mixed binder of gelatin and polyvinylpyrrolidone described in JP-A-59-229556. That's true.

The preferred amount of binder used is usually 0.05 g to 50 g per 1 support, more preferably 0.2 g.
~20g.

Further, the binder was added at 0.00% per 1 g of the dye donor ff.
It is preferable to use 1 to 10 g, more preferably 0.
It is 2 to 5 g.

The heat-developable photosensitive material of the present invention can be obtained by forming a photographic constituent layer on a support, and examples of the support that can be used here include polyethylene film, cellulose acetate film, polyethylene terephthalate film, and polyethylene terephthalate film. Synthetic plastic films such as vinyl chloride, paper supports such as photographic base paper, printing paper, baryta paper and resin coated paper, and supports obtained by coating and curing electron beam curable resin compositions on these supports. Examples include the body.

When the photothermographic material of the present invention and the photosensitive material are of a transfer type and an image receiving member is used, various heat solvents are preferably added to the photothermographic material and/or the image receiving member.

The thermal solvent is a compound that is liquid during thermal development and promotes thermal development and/or thermal transfer. These compounds include, for example, U.S. Pat. No. 3,347,675. No. 3
．． No. 667.959, RD (Research Disclosure) 1th17643 (X II) Japanese Patent Publication No. 1983
-229556, 59-68730, 59-8
No. 4236, No. 60-191251, No. 60-232
No. 547, No. 60-14241, No. 61-52643
No. 62-78554, No. 62-42153, No. 62-4213, etc., U.S. Patent No. 3.438, 7
No. 76, No. 3.666477, No. 3,667.959
Specifications of each issue, JP-A No. 51-19525, JP-A No. 53-24
No. 829, No. 53-60223, No. 58-11864
Examples of organic compounds having polarity such as those described in No. 0 and No. 53-19825 include urea derivatives (e.g., dimethylurea, diethylurea, etc.) that are particularly useful in carrying out the present invention. , phenylurea, etc.), amide derivatives (e.g., acetamide, benzamide, p-toluamide, etc.), sulfonamide derivatives (
Examples include benzenesulfonamide, α-toluenesulfonamide, etc.), polyhydric alcohols (for example, 1.6-hexanediol, 1.2-cyclohexanediol, pentaerythritol, etc.), and polyethylene glycols.

Among the above thermal solvents, water-insoluble solid thermal solvents are particularly preferably used.

Specific examples of the above-mentioned water-soluble heat solvent include, for example, JP-A-62
-136645, 62-139549, 63-
Some of them are described in Japanese Patent Application No. 53548, Japanese Patent Application No. 63-205228, and Japanese Patent Application No. 63-54113.

Examples of the layer to which a heat solvent is added include a photosensitive silver halide emulsion layer, an intermediate layer, a protective layer, an image receiving layer of an image receiving member, etc., and the heat solvent is added to each layer so as to obtain an effect depending on each layer.

The preferred amount of the heat solvent added is usually 10% to 500% by weight, more preferably 30% to 200% by weight of the binder amount.
Weight%.

The organic silver salt and the thermal solvent may be dispersed in the same dispersion. The same binder, dispersion medium, and dispersion device as used for making each dispersion can be used.

In addition to the above-mentioned components, the photothermographic material of the present invention may contain various additives, such as a development accelerator, an antifoggant, and a base precursor, as required.

As development accelerators, compounds described in JP-A-59-177550, JP-A-59-111636, and JP-A-59-124333 are used, as well as compounds described in JP-A-61-159642 and JP-A-62-203908. The development accelerator-releasing compounds described above or metal ions having an electronegativity of 4 or more as described in Japanese Patent Application No. 104645/1988 can also be used.

Examples of antifoggants include those described in US Pat. No. 3,645.
Higher fatty acids described in specification No. 739, Japanese Patent Publication No. 4
Second mercury salt described in Publication No. 7-11113, JP-A-51
-N-halogen compound described in Publication No. 47419, U.S. Patent No. 3,700,457, JP-A-51-50
Mercapto compound releasing compound described in Publication No. 725,
Arylsulfonic acid described in Publication No. 49-125016, No. 51-. Carboxylic acid lithium salts described in Publication No. 47419, British Patent No. 1.455.271, and JP-A-101-1989. Oxidizing agent described in Publication No. O19, 5
Sulfinic acids or thiosulfonic acids described in Publication No. 3-19825, 2-thiouracils described in Publication No. 51-3223, simple sulfur described in Publication No. 5126019, No. 51-42529, No. 51-81124, No. 5
Disulfide and polysulfide compounds described in Publication No. 5-93149, rosin or diterpenes described in Publication No. 51-57435, and free carboxyl l maf, - described in Publication No. 51-104338 had a sulfonic acid group. Polymeric acids, U.S. Pat. No. 4,138,26
Thiazolinthione described in No. 5 Mei page 4, JP-A-1987-
51821, 1,2,4-triazole or 5-mercapto-1,2,4-triazole described in U.S. Patent No. 4,137,079, JP-A-55-1
Thiosulfinate esters described in No. 40883, 1,2゜3,4-thiatriazoles described in No. 55-142331, No. 59-46641, No. 59-5
Dihalogen compounds or trihalogen compounds described in No. 7233, No. 59-57234, and No. 59
Thiol compounds described in JP-111636, hydroquinone derivatives described in JP-6-198540,
Examples include a combination of a hydroquinone conductor and a benzotriazole derivative as described in JP 60-227255.

Still another particularly preferred antifoggant is disclosed in JP-A No. 6
2-78554, a polymer inhibitor described in JP-A No. 62-121452, a polymer inhibitor described in JP-A No. 62-123456, an inhibitor having Balas) M as described in JP-A No. 62-123456. can be mentioned.

Furthermore, colorless couplers described in Japanese Patent Application No. 62-320599 are also preferably used.

Examples of base breaker include compounds that release basic substances by decarboxylation upon heating (e.g., guanidinium trichloroacetate), compounds that decompose through reactions such as intramolecular nucleus displacement reactions, and release amines, etc. For example, Japanese Patent Application Publication No. 56-130745, Japanese Patent Application Publication No. 56-132332, British Patent No. 2,079,480, and U.S. Patent No. 4.0.
60.420 specification, JP-A-59-157637,
No. 59-166943, No. 59-180537, No. 59-174830, No. 59-195237, No. 6
Examples include base releasing agents described in JP2-108249, JP62-174745, and the like.

In addition, various additives used in heat-developable photosensitive materials as necessary, such as antihalation dyes, fluorescent brighteners, hardeners, antistatic agents, plasticizers, spreading agents, matting agents, and surfactants. , anti-fading agents, etc. can be contained, and these are specifically described in RD (Research Disclosure) magazine Vol. 1170, . June 1978 702
No. 9, JP-A-62-135825, etc.

These various additives may be added not only to the photosensitive layer but also to non-photosensitive layers such as an intermediate layer, a protective layer or a backing layer.

The heat-developable photosensitive material of the present invention contains (al photosensitive silver halide, (b) a dye-providing substance, and (C) a binder.

Furthermore, it is preferable to contain (d) a reducing agent and (el) organic silver as necessary.These may basically be contained in the heat-developable photosensitive layer, but they are not necessarily included in a single photographic constituent layer. For example, the heat-developable photosensitive layer is divided into two layers, and the above-mentioned (a), (C1, (el).

The component (d) may be contained in one heat-developable photosensitive layer and the dye-providing substance (b) may be contained in the other layer adjacent to this photosensitive layer, in a state where they can react with each other. If necessary, it may be contained in two or more constituent layers.

Further, the heat-developable photosensitive layer may be divided into two or more layers: a low-sensitivity layer and a high-sensitivity layer, a high-density layer and a low-density layer, or more.

The heat-developable photosensitive material of the present invention has one or more heat-developable photosensitive layers. In the case of full-color photosensitive materials,
Generally, it has three heat-developable photosensitive layers with different color sensitivities, and in each photosensitive layer, dyes with different hues are formed or released by heat development.

Usually, a yellow dye is used in the blue-sensitive layer, a magenta dye is used in the green-sensitive layer, and a cyan dye is used in the red-sensitive layer, but the combination is not limited thereto. It is also possible to combine a near-infrared sensitive layer.

The structure of each layer can be arbitrarily selected depending on the purpose. For example, a structure in which a red-sensitive layer, a green-sensitive layer, and a blue-sensitive layer are sequentially formed on a support, or a blue-sensitive layer is sequentially formed on a support. , a green-sensitive layer, a red-sensitive layer, or a green-sensitive layer, a red-sensitive layer, and a blue-sensitive layer sequentially on the support.

In addition to the heat-developable photosensitive layer, the heat-developable photosensitive material of the present invention may optionally include non-photosensitive layers such as an undercoat layer, an intermediate layer, a protective layer, a filter layer, a backing layer, and a release layer. . To coat the heat-developable photosensitive layer and these non-photosensitive layers on the support, a method similar to that used for coating and preparing general silver halide photosensitive materials can be applied.

The heat-developable photosensitive material of the present invention can be exposed to light using an appropriate light source, and examples of the exposure light source include a tungsten lamp,
Various types such as halogen lamps, xenon lamps, mercury lamps, cathode ray tube flying spots, light emitting diodes, lasers (e.g. gas lasers, YAG lasers, dye lasers, semiconductor lasers, etc.), CRT light sources, and FOT can be used singly or in combination. It can be used as Semiconductor laser and second harmonic generating element (SHG element)
etc. can also be used. In addition, electron beam, X! L
Exposure may be performed using light emitted from a phosphor excited by T-rays, α-rays, or the like. Exposure times include not only exposure times of 1/1000 seconds to 1 second that are normally used with cameras, but also exposures shorter than 1/1000 seconds, such as exposures of 1/10 to 1/10" seconds using xenon flash lamps and cathode ray tubes. If necessary, the spectral composition of the light used for exposure can be adjusted with a color filter.The light-sensitive material of the present invention can be used for scanner exposure using a laser or the like.

The heat-developable photosensitive material of the present invention usually preferably has a
0°C to 200°C, more preferably 100'C to 170°C
Developing can be carried out simply by heating within a temperature range of, preferably 1 second to 180 seconds, more preferably 1.5 seconds to 120 seconds. Transfer of the diffusible dye to the image-receiving layer may be carried out simultaneously with heat development by bringing the image-receiving member into close contact with the photosensitive surface of the photosensitive material and the image-receiving layer during heat development, or by bringing the image-receiving member into close contact with the image-receiving member after heat development. Alternatively, the transfer may be carried out by applying water and then applying heat if necessary, or preheating may be performed in a temperature range of 70° C. to 180° C. before exposure. Also, JP-A-60-1
As described in No. 43338 and No. 61-162041, in order to improve their mutual adhesion, the photosensitive material and the image receiving member may be preheated at a temperature of 80°C to 250°C immediately before thermal development transfer. good.

Various heating means can be used for the heat-developable photosensitive material of the present invention.

As the heating means, any method that can be applied to ordinary heat-developable photosensitive materials can be used, such as contacting with a heated block or plate, contacting with a heated roller or drum, or passing through a high-temperature atmosphere. Alternatively, high-frequency heating may be used, or furthermore, a conductive layer containing a conductive substance such as carbon black may be provided on the back surface of the photosensitive material of the present invention or the back surface of the image receiving member for thermal transfer, and the Joule heat generated by energization may be utilized. You can also do that. There are no particular restrictions on the heating pattern, and the temperature can be raised continuously, such as by preheating and then reheating, or by heating at a high temperature for a short time or at a low temperature for a long time. , lowering the temperature continuously, or repeating these steps. Furthermore, discontinuous heating is also possible, but a simple pattern is preferable. Alternatively, a method in which exposure and heating proceed simultaneously may be used.

When the present invention is applied to a transfer type photothermographic material, an image receiving member is used as described above. In this case, the image-receiving layer that can be effectively used in the image-receiving member may be one that has the function of receiving the dye in the heat-developable photosensitive layer released or formed by heat development, such as tertiary amine or quaternary amine. Polymers containing ammonium salts, U.S. Patent No. 3.709.69
Those described in the specification of No. 0 are preferably used. Typical image-receiving layers for diffusion transfer include those obtained by mixing a polymer containing ammonium salt, tertiary amine, etc. with gelatin, polyvinyl alcohol, etc., and coating the mixture on a support. Another useful dye-receiving material is one made of a heat-resistant organic polymer material having a glass transition temperature of 40 DEG C. or higher and 250 DEG C. or lower, as described in Japanese Patent Application Laid-Open No. 57-207250.

These polymers may be supported on a support as an image-receiving layer, or may themselves be used as a support.

Regarding polymers, ``Polymer Handbook, 2nd Edition'' (Jitsui Brand Wrap, E.H. Inmargatsutori John Willi & Sons Publishing) (Polymer Handbook 2nd Edition)
, (J,Brandrup+E,H,Ima+erg
Also useful are synthetic polymers having a glass transition temperature of 40° C. or higher, as described in John Wiley & John Wiley et al. - The molecular weight of the polymer substance in the shell is usefully between 2,000 and 200,000. These polymeric substances may be used alone or in a blend of two or more types, or may be used in combination of two or more types as a copolymer.

A particularly preferable image-receiving layer is JP-A-59-22342
Examples include a layer made of polyvinyl chloride described in Japanese Patent Publication No. 5, and a layer made of polycarbonate and a plasticizer described in JP-A-60-19138.

These polymers can also be used as a support and an image-receiving layer (image-receiving member), in which case the support may be formed from a single layer or from multiple layers. good.

As the support for the image-receiving member, any material such as a transparent support or an opaque support may be used, and examples thereof include films of polyethylene terephthalate, polycarbonate, polystyrene, polyvinyl chloride, polyethylene, polypropylene, and supports thereof. Supports containing pigments such as titanium oxygen, barium sulfate, calcium carbonate, and talc, baryta paper, resin coated paper laminated with thermoplastic resin containing pigments on paper, fabrics, glasses, Supports made of metals such as aluminum, etc., and supports prepared by coating and curing electron beam curable resin compositions containing pigments on these supports, and coating layers containing pigments on these supports. Examples include a support provided with. Furthermore, various coated papers such as the cast coated paper described in JP-A-62-283333 are also useful as supports.

In addition, a support with a pigment-containing electron beam curable resin composition coated and cured on paper, or a support with a pigment coating layer on paper and an electron beam curable resin composition on the pigment coating layer. The resin layer of the support coated with and cured can be used as an image-receiving layer, so it can be used as is as an image-receiving member.

Appropriate additives, such as various known additives, can be added to the image receiving member. Examples of such additives include ultraviolet absorbers, image stabilizers, development accelerators, antifoggants, pHtm adjusters (various acids and acid precursors, bases and base precursors, etc.), and hot solvents. can be mentioned.

Typical examples of ultraviolet absorbers include benzotriazole compounds and benzophenone compounds. Examples of image stabilizers include hindered amine type, hindered phenol type, dialkoxybenzene type, chroman type, indane type, thioether type,
Examples include hydroquinone-based and chloro-substituted S-triazine-based compounds. The development accelerator and antifoggant can be appropriately selected from compounds added to heat-developable photosensitive materials.

The heat-developable photosensitive material of the present invention is published in RD (Research Disclosure Magazine) No. 15108, JP-A-57-1984.
No. 58, No. 57-207250, No. 61-80148
The photothermographic material may be a so-called monosheet type photothermographic material in which a photosensitive layer and an image-receiving layer are formed on the same support, as described in the above publication.

The heat-developable photosensitive material of the present invention is preferably provided with a protective layer.

Various additives used in the photographic field can be used in the protective layer. The additives include various matting agents, colloidal silica, slipping agents, organic fluoro compounds (especially fluorine surfactants), antistatic agents, ultraviolet absorbers,
High-boiling organic solvents, antioxidants, hydroquinone derivatives,
Polymer latex, surfactants (including polymeric surfactants), hardeners (including polymeric hardeners), organic silver salt particles, non-photosensitive silver halide particles, antifoggants, development accelerators, etc. can be mentioned.

Regarding these additives, please refer to RD (Research Disclosure Magazine) Vol. 0. June 1978! 17029 and JP-A-62-135825.

Margin below.

〔Example〕

Hereinafter, specific examples of the present invention will be described. However, as a matter of course, the present invention is not limited to the examples described below.

Example 1 In this example, microcapsules were prepared as follows.

Preparation of Microcapsules-1 <Method for producing gelatin capsules by complex coacervation method> The above-mentioned Exemplary Compound (7) was used as the compound of the present invention, and 20 g of it and 20 g of tricresyl phosphate were dissolved in 50 d of ethyl acetate. . 100 mj of an aqueous gelatin solution containing the obtained solution, 10 rIi of 5% by weight of Alkanol XC (registered trademark, manufactured by DuPont), and 10 g of photographic gelatin! After dispersing with an ultrasonic homogenizer, ethyl acetate was distilled off to obtain an emulsified dispersion of oil droplets containing exemplary compound (7), which is a compound of the present invention. To this emulsified dispersion solution, 100 d of a 10% aqueous solution of gum arabic was added and mixed for 10 minutes.

After further adding 450 d of 40°C warm water, the pH was adjusted to 4.3 with 10% acetic acid. After cooling to 5°C, 10In1 of 70% formalin was added dropwise, the pH was adjusted to 9 with a 10% aqueous sodium hydroxide solution, the temperature was raised to 50°C, and after stirring for a while, centrifugation was repeated to form microcapsules. −
I got 1.

Preparation of microcapsules-2 (method for producing formaldehyde resin capsules by in situ polymerization) 37
Add IOg of melamine to 30g of formalin and heat at 60°
React for 15 minutes at C, then add 1.5 g of glycine,
Let it react for 1 minute and prepare the prepolymer aqueous solution for 11! ! ! ! did. Next, the above-mentioned exemplary compound (1) 2 which is a compound of the present invention
The above prepolymer aqueous solution was added to 150 g of an emulsified dispersion containing 0 g of tricresyl phosphate and 20 g of tricresyl phosphate with stirring, the pH was adjusted to 3.5 with a 10% citric acid aqueous solution, and the mixture was heated at 60 °C for 30 g. After the reaction, add 40ml of warm water.
was added, and the reaction was continued for an additional 3 hours.

After adding this to 200 mff1 of cold water, microcapsules-2 were obtained by centrifugation.

By3gJ of Microcapsules-3 to 15 Microcapsules-3 to 15 were prepared in the same manner as described above to have the core material and wall material shown in Table 1. Table-1
In the lower margin of the microcapsule, TCP: ) Recresyl phosphate DOP Nidioctyl phthalate DBP Nidibutyl phthalate Preparation of microcapsules-16 to 20 Furthermore, microcapsules-1, 2, 4, 12, and 15 are prepared. At the same time, sodium tetraphenylboron is added to the dispersion of the compound of the present invention (the amount added is 30% of the compound of the present invention).
Microcapsules 16, 17, 18, 19, and 20 were prepared in the same manner as above (mol%).

Comparative Example In place of the compound of the present invention, encapsulation was investigated using the following coloring agent as a core material in the same manner as in the preparation method of the above example. However, it was not possible to obtain capsules containing the following compound as a core material.

Example 2 In this example, a silver iodobromide emulsion, a dispersion of an organic silver salt and a heat solvent, a dye-providing substance dispersion, and a reducing agent dispersion were prepared as follows, and these were used to heat the A developable color photosensitive material was prepared. Further, an image receiving member was prepared as described below.

■Preparation of silver iodobromide emulsion At 50°C, JP-A No. 57-92523, No. 57
Using the mixing agitator shown in the specification of -92524,
Add 11.6 g of potassium iodide to solution (A) in which 20 g of ossein gelatin, 10,100 O of distilled water, and ammonia are dissolved.
(B) is an aqueous solution containing 131 g of potassium bromide and 131 g of potassium bromide. &500d and 500ml of solution (C), which is an aqueous solution containing 1 mol of silver nitrate and ammonia, were simultaneously added while II) keeping the Ag constant.

The shape and size of the emulsion grains to be prepared are as follows: pH5pAg and (
It was adjusted by controlling the addition rate of liquid B) and liquid (C). In this way, silver iodide content of 7 mol%, regular octahedron,
A core emulsion with an average grain size of 0.25 μm was prepared.

Next, in the same manner as above, a shell of silver halide with a silver iodide content of 1 mol % was coated with a core/shell type silver halide having a regular octahedral shape and an average grain size of 0.3 μm. An emulsion was prepared (monodispersity was 9%). The emulsion thus prepared was washed with water and desalted.

■Preparation of photosensitive silver halide dispersion The following components were added to 100 ml of the silver iodobromide emulsion prepared as described above, and chemical sensitization and spectral sensitization were carried out. Each photosensitive silver halide emulsion dispersion was prepared.

(a) Preparation of red-sensitive silver iodobromide emulsion 100 m of the above silver iodobromide emulsion 14-hydroxy-6-methyl-1°3.3a,7-titrazaindene 0.4 g gelatin 32 g sodium thiosulfate 10 ■ The following sensitizing dye ( a) 0 m2 of 1% methanol solution Distilled water 1200 m1 Sensitizing dye (a) (b) Preparation of green-sensitive silver iodobromide emulsion Said silver iodobromide emulsion 100 m14-Hydroxy-6-methyl-1°3.3a,7- Chitrazaindene 0.4 g Gelatin 32 g Sodium thiosulfate 10 mg Sensitizing dye (b) below
Methanol 1% solution 0mft Distilled water 1200mff1
(C) Preparation of blue-sensitive silver iodobromide emulsion 100 m of the above silver iodobromide emulsion 14-hydroxy-6-methyl-1°3.3a,7-chitrazaindene 0.4 g gelatin 32 g sodium thiosulfate 10 mg ) 1% methanol solution 80% distilled water 1200d sensitizing dye (c) ■Dispersion of organic silver and thermal solvent A dispersion of organic silver salt and thermal solvent was prepared based on the following formulation.

Prescription: Penztriazole 60.5 g Hot Solvent 6 (below) 346 g Polyvinylpyrrolidone (10%) 446#li! in water
The weight shall be 2000 g.

A dispersion of an organic silver salt and a hot solvent was prepared by dispersing with an alumina pole.

Thermal solvent - A ■ Preparation of dispersion of dye-donating substance 60 g of the following polymeric dye-providing substance (1), the following inhibitor -
0.037 g of B, and 7 g of the following scavenger C
．． 2g of tricresyl phosphate and 30g of tricresyl phosphate.
, dissolved in 400 d of ethyl acetate, and further dissolved in alkanol XC
5% by weight aqueous solution 18G-1 and 36g of photographic gelatin
Gelatin aqueous solution containing 360mj! After mixing and dispersing with an ultrasonic homogenizer and distilling off ethyl acetate,
00/d to obtain a dispersion of the dye-providing substance.

■Preparation of hot solvent dispersion 150 g of the hot solvent-A, 1% polyvinylpyrrolidone 2
50d, pure water 200mff1. 5% of Alkanol XC
25 d of the aqueous solution was mixed and dispersed in an alumina ball mill to prepare a hot solvent dispersion.

Polymer dye donor f(1) Inhibitor (B) Di2115 Scavenger (C) ■Preparation of heat-developable color photosensitive material Using the above dispersion on a 180 μm thick transparent polyethylene terephthalate film coated with latex undercoat. Each composition was coated in the following amount per support, and then dried to prepare Photosensitive Material-1. Note that the pH of the coating liquid was adjusted to 6.0.

Microcapsules of the present invention - 11.5 g Benztriazole silver 1.2 g Heat solvent - A
5. Og polymeric dye-donor substance (1
) 1.3g inhibitor - (B)
o, s■gelatin
3.8g green sensitive silver halide
0.5gAg polyvinylpyrrolidone
0.2g tricresyl phosphate 0
．． 65g Scavenger (C) 0.
Each of the above layers further contained the following hardener and surfactant.

Hardener CI+2 = Cl1SOzCHzOCHzS(hclI
=ClI2 surfactant ■ Creation of image receiving member A polyvinyl chloride (Ji 12 g/m) layer (image receiving M) containing the following compound (applied as shown below) was coated on photographic baryta paper to form an image receiving member. Created.

HOCHgCJbSCII□CIItSCIItCHt
After exposing the photosensitive material obtained above through a step wedge, the photosensitive material was stacked on the image receiving member so that the photosensitive layer surface and the image receiving layer surface were in close contact with each other, and the photosensitive material was heated at a temperature of 140°C for 4 hours.
Heat development was performed for 0 seconds. When the image receiving member was peeled off, a magenta image having the maximum density (D max) and minimum density (Dmin) shown in Table 2 was obtained on the image receiving member.

Also, separately, microcapsules of the present invention of photosensitive material-1
was changed to microcapsules 2 to 20, and photosensitive materials 2 to 20 having the same structure as photosensitive material 1 except for that were prepared.

The amount of microcapsules 2 to 20 added is based on the addition ft (mol) of the compound of the present invention, which is a core substance, compared to the photosensitive material 1.
The amount of the core substance (compound-1 of the present invention) added to microcapsule-1 was adjusted to be the same as that of microcapsule-1.

In addition, as comparative samples, the following color developers (compounds F, E, the same molar amount as compound-1), color developer precursors (compounds F, G,
Light-sensitive materials-21 to 24 were prepared, each containing 3 times the molar amount of compound-1).

The obtained photosensitive materials-2 to 24 were exposed and developed in the same manner as in Example-1 to obtain magenta transferred images. Maximum density (Dmax) and minimum density (D
min) are shown in Table-2.

As shown in Margin Table 2 below, the photosensitive materials (Photosensitive Materials-1 to 20) containing the color developing agent of the present invention are different from the comparative photosensitive materials (Photosensitive Materials-1 to 20) using the known color developing agent E. 21, 22), the fog (minimum density) is significantly improved.
Further, the maximum density is significantly improved compared to comparative light-sensitive materials (Photosensitive materials-23 and 24) using known color developer precursors F and G.

Example 3 On a transparent polyethylene terephthalate film having a thickness of 180 μm and coated with a latex undercoat, each composition was coated in the following amounts per 1 nf of support to provide a color developer layer. The pH of the coating solution was adjusted to 6.0.

Microcapsules of the present invention -191.5g hot solvent-
(A) 3.6g gelatin
3.Og A photosensitive layer consisting of the composition shown below (applied per 1M) was coated on the above layer to obtain a heat-developable window optical material-25. Furthermore, the coating liquid p
The H value was adjusted to 6.0.

Gelatin 3.8gPyrolucent silver halide 0.5gAgPolyvinylpyrrolidone 0.2gPenztriazole industry standard 1.2gHeat solvent (A
) 5. Og polymeric dye donor (1) 1.3g tricresyl phosphate 0.65g scavenger (C
) 0.16g inhibitor-(B)
In addition, 1.0 g/rr of microcapsules-19 of the present invention was added to the photosensitive layer.
A photosensitive material-26 was prepared in which a quantity of f was added, and a photosensitive material-27 was prepared in which a color developer precursor (F) was added in a quantity of 1.5 g/nf.

The obtained photosensitive material was exposed to light and thermally developed in the same manner as in Example 2 to obtain a magenta transferred image.

Maximum density (D max) and minimum density (D max) of the obtained image
Dmin) is shown in Table 3.

Table 3 As shown in Table 3, the layer (non-photosensitive N) in which the microcapsules of the present invention are separated from the silver halide-containing layer (photosensitive layer)
The effects of the present invention can be achieved even when added to.

Furthermore, the capsules of the present invention may be added to both the photosensitive layer and the non-photosensitive layer, or may be used in combination with a color developer precursor, both of which are found to be effective.

Example-4 <Storability test> Photosensitive materials-1 to 27 were stored at a relative humidity of 80% and a temperature of 50°C.
After being left for 48 hours under these conditions, heat development was performed under the same conditions as in Example-2. The maximum density (D max
), the minimum density (Dmin), and the sensitivity before standing to 10
Table 4 shows the relative sensitivity of each photosensitive material after being left at 0.

Margin Table 4 Below: Photosensitive materials 21 and 22 cannot be evaluated due to decreased sensitivity and too large fog. In comparison, the storage stability is significantly improved, and the storage stability is equal to or higher than that of Photosensitive Material-23 using a color developer precursor.

Example-5 Multilayer photosensitive material of m strength shown in Tables-5 and 6-28°29
It was created. After exposing the obtained light-sensitive material to blue, green, and red light, the same observation as in Example 2 was performed, and yellow, magenta, and cyan transfers were observed corresponding to each exposure. Image obtained.

The transfer density (maximum density Dmax, minimum density D+width) of the obtained image is shown in Table-7.

Polymeric dye-providing substance - (2) C11° Polymeric dye-providing substance - (3) Polymeric dye-providing substance (4) Polymeric dye-providing substance - (5) Table 7 As shown in Table 7, the microorganism of the present invention Heat-developable color photosensitive materials using capsules, as well as multilayer photosensitive materials,
Good maximum density (D + max) and minimum density (Dmi
A color image showing n) could be formed. Further, when these photosensitive materials were separately subjected to the same storage test as in Example 4, the storage stability was also good.

〔Effect of the invention〕

As mentioned above, the heat-developable color photosensitive material of the present invention can produce high-density color images in a short time and at a relatively low temperature, has good storage stability, and is free from stains on white background areas. ), and has the effect that clear color images can be obtained.

Claims (1)

[Claims] 1. A thermal method comprising, on a support, a capsule material having at least a photosensitive silver halide, a dye-donating substance, a binder, and a hydrophobic salt of a color developer as a core material and having a water-insoluble polymer wall. Developable color photosensitive material.