JPS634233A - Heat developable photosensitive material superior in heat development processing stability and long storage stability - Google Patents

Abstract

PURPOSE:To obtain a heat-developable photosensitive material having superior stability in heat development processing and long-term storage by forming a layer for temporarily interrupting participation of the acid component of the heat-developable photographic material. CONSTITUTION:The heat developable photographic material comprises at least a support, photosensitive silver halide, a dye donor, a reducing agent, the acid component, and a binder, and it is provided with the interrupting layer for temporarily interrupting the participation of the acid component, and this interrupting layer itself may contain the acid component, but it is preferred to form this interrupting layer part from the acid component-containing layer on the side of the photosensitive layer, especially, in the order of the acid component-containing layer, the interrupting layer, and the photosensitive layer, and the interrupting layer comprises a polymer, such as gelatin or a mixture of gelatin and polyvinylpyrrolidone, as a binder in an amount of 0.55-50g, preferably, 1.0-10g per 1m<2> of the layer, and it is preferred to contain a heat- meltable solvent, such as urea or N-methylurea.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat-developable photosensitive material, and more particularly to a heat-developable photosensitive material having excellent thermal development processing stability and long-term storage stability.

BACKGROUND OF THE INVENTION A method in which the development step for obtaining an image is performed by dry heat treatment has many advantages over conventional wet methods in terms of processing time, cost, and concerns about pollution.

Regarding heat-developable photosensitive materials in which the above-mentioned development process can be carried out by dry heat treatment, for example, Japanese Patent Publication No. 43-4921 and No.
This is described in Japanese Patent No. 3-4924, which discloses a black and white type photothermographic material comprising an organic silver salt, silver halide and a reducing agent.

Attempts have also been made to improve such heat-developable photosensitive materials and obtain color images by various methods.

For example, JP-A-57-179840, JP-A No. 57-186
No. 744, No. 57-198458, No. 57-207
No. 250, No. 58-40551, No. 58-58543
No. 58-79247, No. 59-12431, No. 59-22049, No. 59-68730, No. 59
-124339, 59-124333, 59
-124331, 59-159159, 59
-181345, 59-159161, 58-
No. 116537, No. 58-123533, No. 58-1
There are No. 49046 and No. 58-149047.

The basic composition of a color type heat-developable photosensitive material for obtaining color images consists of a photosensitive element and an image-receiving element, and the photosensitive element basically consists of a photosensitive silver halide, an organic silver salt, a reducing agent, a dye-donating substance, It consists of a binder.

In the former black and white type, optical information is given to the photosensitive silver halide by image exposure, and during thermal development, the exposed photosensitive silver halide and the reducing agent in the photosensitive layer are present in the vicinity. The catalytic action of silver halide causes an oxidation-reduction reaction to produce silver, and the exposed areas of the photosensitive layer turn black to form a silver image.

In addition, in the color type, optical information is given to the photosensitive silver halide by image exposure, and in heat development,
A dye that forms an image is released or formed by the reaction of a dye-providing substance in response to or inversely to the reduction reaction of silver halide. The image-forming dye obtained by thermal development is transferred to an image-receiving element to form an image.

In the above-mentioned heat-developable photosensitive materials, development is carried out by high-temperature heating. However, since the heat-developable photo-sensitive materials require time to lower the temperature after being heated to high temperatures, development may proceed too much, or the same heating method may cause problems. However, the development process becomes unstable due to variations in conditions such as heating temperature, heating atmosphere temperature, water content of the photosensitive material, and heating time. To avoid such development instability, compounds which react with bases to release development stoppers, such as those described in U.S. Patent No. 4.009.029, Research Disclosure 123
A method using an acid polymer described in Vol. 22, Vol. 180, 18030 has been proposed, but the development stopping effect is insufficient.

Furthermore, for example, JP-A-49-58642, JP-A-50-5
The compound described in No. 7452 had the drawback of lowering image density. For example, JP-A-60-108837,
No. 60-192939 and No. 60-230133 describe the use of a new acid-releasing compound to prevent and improve image density.

However, even when these compounds are used, it is still insufficient to prevent a decrease in image density, and improvements have been desired. On the other hand, heat-developable photosensitive materials containing these compounds have the disadvantage that capri increases and image density decreases during long-term storage.

[Object of the Invention] An object of the present invention is to provide a heat-developable photosensitive material that has excellent heat development processing stability and long-term storage stability.

[Structure of the invention]

As a result of extensive studies, the present inventors have found that, in a heat-developable photosensitive material having at least a photosensitive silver halide, a dye-providing substance, a reducing agent, an acidic component, and a binder on a support, the involvement of the acidic component can be temporarily eliminated. The present inventors have discovered that the above objects of the present invention can be achieved by a heat-developable photosensitive material having at least one shielding layer, and have thus completed the present invention.

[Specific structure of the invention] The layer that temporarily shields the involvement of acidic components in the present invention (hereinafter referred to as the shielding layer of the present invention) refers to the layer that temporarily blocks the involvement of acidic components in the photosensitive layer during thermal development. For example, a layer whose function is to temporarily isolate the photosensitive layer and the acidic component or to temporally control the reaction between the photosensitive layer and the acidic component. It is.

The shielding layer of the present invention may be provided separately from the layer containing the acidic component, or may be the same as the layer containing the acidic component,
It is particularly preferable to provide the layer separately from the layer containing the acidic component. Further, the shielding layer of the present invention and the layer containing an acidic component are preferably provided on the photosensitive layer side, and in particular, the acidic component-containing layer, the shielding layer of the present invention, and the photosensitive layer are preferably provided on the support in this order. is preferred. The shielding layer of the present invention is basically a layer containing a polymeric substance as a binder.

Binders for the shielding layer of the present invention include gelatin, gelatin modified with an acylating agent, natural polymer compounds such as casein, polyvinyl alcohol, hydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, ethylcellulose, cellulose acetate, Polyvinyl acetate, partial hydrolyzate of polyvinyl acetate, polyvinylpyrrolidone, polyvinylpyrrolidone-acrylic acid copolymer, polyvinylpyrrolidone-acrylic acid ester copolymer, polyvinylpyrrolidone-vinyl alcohol copolymer, polyvinylpyrrolidone-vinyl acetate copolymer Polymer, polyvinyl biOlidone-acrylamide copolymer, polyvinylpyrrolidone-vinylimidazole copolymer, polyvinylpyrrolidone-vinyl carbinol copolymer, polyvinylpyrrolidone-vinyl alkyl ether copolymer, polyethylene glycol, polyethylene glycol ester, polymetha Methyl acrylate, polyethyl methacrylate, polyethyl acrylate, polyethyl acrylate, polyacrylamide, polymethacrylamide, polydiacetone acrylamide, ethylene-
Examples include synthetic polymer compounds such as vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, and mixtures thereof.

Furthermore, Research Disclosure Magazine page 86 (197
6), U.S. Patent No. 4,056,394, U.S. Patent No. 4,061
Latexes of methyl acrylate-vinylidene chloride-itaconic acid copolymer and acrylonitrile-vinylidene chloride-acrylic acid copolymer as described in No. 496 may also be used. Also, latex of styrene-butyl acrylate-acrylic acid copolymer, styrene-butyl acrylate-acrylic acid-glycidyl acrylate copolymer, butyl methacrylate-acrylic acid copolymer, butyl methacrylate-itaconic acid, phenyl acrylate-acrylic acid copolymer, etc. Latex such as a polymer or other latex may be used. A combination of these may also be used.

The binder used in the shielding layer of the present invention is -1 per layer.
o for f, osg ~ 509, preferably 0
．． It is 1 g to 10 g.

One of the preferred embodiments of the present invention is that the shielding layer of the present invention contains a thermal solvent.

The thermal solvent used in the present invention is a compound that promotes thermal development and/or thermal transfer. These compounds are described in, for example, U.S. Pat.
, No. 667.959, Research ◆ Disclosure N
O, 17643 (X 'II'), Japanese Unexamined Patent Publication No. 1983-
229556, Japanese Patent Application No. 59-47787, etc., and those particularly useful in the present invention include urea derivatives such as dimethylurea, diethylurea, phenylurea, etc.), amide derivatives (e.g., acetamide, benzamide, etc.), polyhydric alcohols (e.g., 1,5-bentanediol, 1,6-bentanediol, 1,2-cyclohexanediol, pentaerythritol, trimethylolethane) etc.) or polyethylene glycols.

The method of adding the thermal solvent to the shielding layer of the present invention is not particularly limited, but it can be added by pulverization and dispersion using a ball mill, sand mill, etc., it can be added by dissolving it in an appropriate solvent, or it can be added by dissolving it in a high boiling point solvent. There is a method of adding it as an oil-in-water type dispersion.

The amount of the heat solvent added to the shielding layer of the present invention is preferably 5 to 200% by weight, more preferably 10 to 100% by weight, calculated from the dry coating thickness of the layer. Another preferred embodiment of the present invention is that the shielding layer of the present invention contains a substance that dissolves or swells with a hot solvent at a heat development temperature.

As the heat solvent, the above-mentioned ones can be used, and the layer to be added may be the shielding layer of the present invention, other photosensitive silver halide emulsion layers, intermediate layers, protective layers, image receiving layers of image receiving members, or It can be used by being added to a layer containing an acidic substance. When a thermal solvent is added to a layer other than the shielding layer of the present invention, it is necessary that the thermal solvent comes into contact with the shielding layer of the present invention during thermal development.

The shielding layer of the present invention in this embodiment contains a substance that dissolves or swells with a hot solvent at the heat development temperature, and this substance may be a polymer or a low-molecular compound. This substance is selected in combination with the thermal solvent used, and the combination can be easily selected by those skilled in the art. For example, weigh a hot solvent and the substance to be tested in a test tube, heat it at a temperature equivalent to the heat development temperature (for example, 150°C), and observe whether it dissolves or swells to determine whether the combination is appropriate. You can make a judgment and select a preferred combination.

A more preferred embodiment is a case where the binder of the shielding layer of the present invention is a substance that dissolves or swells with a hot solvent at the heat development temperature.

In this case, a combination in which the thermal solvent is urea or N-methylurea and the binder of the shielding layer of the present invention is gelatin or a mixture of gelatin and polyvinylpyrrolidone is particularly preferred.

In the present invention, as the acidic component, plain or organic acids can be used, but organic acids are preferred.

As an inorganic acid, Ml! iQ,! acid, nitric acid, phosphoric acid,
Citric acid, boric acid, metaboric acid, etc. can be used.

As the m-acid, aliphatic carboxylic acids, aromatic carboxylic acids, aliphatic sulfonic acids, aromatic sulfonic acids, aliphatic monosulfuric esters, aromatic monosulfuric esters, etc. can be used. Further, the organic acid may be a high molecular compound, that is, a polymeric acid.

In the present invention, polymeric acids are preferably used as the acidic component, such as homopolymers of unsaturated organic acid monomers and copolymers of unsaturated chelating acid monomers and other vinyl polymers.

Examples of the unsaturated organic acid monomers used include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, and crotonic acid.

In addition, there are no particular restrictions on the vinyl monomers that can be copolymerized with the unsaturated organic acid monomers, in which phosphonic acids, sulfonic acids, etc. having vinyl groups, and acid anhydrides such as maleic anhydride can be used. Examples include acrylic esters such as methyl acrylate, ethyl acrylate, and butyl acrylate, styrenes, acrylonitriles, vinyl chlorides, vinylidene chlorides, and divinylbenzenes.

Furthermore, in synthesizing a polymeric acid, it is not necessarily necessary to use an organic acid monomer having a vinyl group as a raw material; for example, it is also possible to react with sulfuric acid to a hydroxyl group in a polymer to form a monosulfate ester.

Specific examples of the polymer acids used in the present invention are described below, but the present invention is not limited to tIII.

Tumor tumor (S-1) I x : y = 70 : 30 (molar ratio) (S-
2) x: y-70: 30 (molar ratio) (S-3) x:y=so:2o (molar ratio) (S-4) x: y=70 = 30 (molar ratio) (S-S) x : y = 80 : 20 (molar ratio) (S-6) (S-7) l x : y = 70:30 (molar ratio) (S-S) Burnt J' Examples include, but are not limited to, the following low molecular weight organic acids.

(A-1) HOOC (CHz) COOH but n
= O(A-2) Same as above, but n
= 1 (A-3) Same as above, but n = 2 (A-4) Same as above, but n
= 4 (A-5) Same as above, but n = 6 (A-6) Same as above, but n = 8 (A-7) Same as above
However, n=10 (A-8) (A-10) (A-zl) (A-12) HO-CH-COOH CH2C00H (A-13) CH2COOH HO-C-COOH CH2C00H (A-14) HO-CH -COOH HO-CH-COOH (A-15) (A-16) 0OH (A-17) (A-18) (A-20) (A-22) 0 l Cx5Hst -0-S -OH (A- 24) C2H5-0-P-OH ■ OH (A-25)0 C4H,-0-P-OH OH (A-26) CH3(CH2)nC00H However, n=8(A-27)
Same as above Monthly n=10 (A-28) Same as above
Above, however, n = 12 (A-29) Same as above However, n = 14 (A-30) Same as above
However, n=16 (A-31) Same as above
However, n=18 (A-32) Same as above
However, in the present invention, n=22, an acid precursor is preferably used. Acid precursors are compounds that release acidic components when heated.

Preferred acid precursors include JP-A-60-108
No. 837 and No. 60-192939, Human O-xam carboxylates that release acid through Rossen rearrangement, JP-A-5
Aldoxime carboxylates and the like which generate o-23o133@ nitrile and simultaneously release acid can be used.

One of the effective acid precursors is a compound having a partial structure represented by the following general formula [I]. However, the bonds at both ends of the partial structure [I] are bonded to carbon atoms.

General formula [I] -C-N-0-C- Among the acid precursors having a partial structure represented by the above general formula [I], those which can be particularly usefully used in the present invention are the following - general formula [II] It is a compound represented by

-General Formula [II] (R+ -C=N -OC+7-82 In the formula, R1 represents an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group or a heterocyclic group. nl represents an integer of 1 to 3. R1 represents an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group when nl is 1, and when nl is 2 to
3 represents a group each having 2 to 3 bonds derived from an alkyl group, a cycloalkyl group, an aryl group, or a heterocyclic group.

The alkyl group represented by R1 and R2 may be linear or branched, preferably having 1 to 18 carbon atoms, and this alkyl group also includes those having a substituent.

Examples of substituents for alkyl groups include halogen atoms, aryl groups, alkoxy groups, cyano groups, optionally substituted carbamoyl groups, water M groups, and carboxy groups. Specific examples of the alkyl group represented by R+ R3 and R2 include methyl group, ethyl group, propyl group, butyl group, hexyl group, decyl group, dodecyl group,
Examples include benzyl group.

The cycloalkyl group represented by R1 and R2 is preferably a 5- or 6-membered cycloalkyl group having 5 to 10 carbon atoms, and this cycloalkyl group also includes those having a substituent. Examples include the same groups as those mentioned for the alkyl group. Examples of the cycloalkyl group represented by R1 and R2 include a cyclopentyl group and a cyclohexyl group.

The alkenyl group represented by R1 includes those having a substituent, and examples of the substituent include the same groups as mentioned above for the alkyl group.

Examples of the alkenyl group represented by R1 include a vinyl group, an allyl group, and a styryl group.

The aryl group represented by R1 and R2 is preferably an aryl group having 6 to 18 carbon atoms, such as a phenyl group, a naphthyl group, an anthryl group, etc., including those having a substituent.

Examples of substituents for aryl groups include alkyl groups, aryl groups, halogen atoms, alkoxy groups, aryloxy groups, hydroxyl groups, mercapto groups, amine groups, acylamino groups, sulfonylamino groups, cyano groups, nitro groups, alkylthio groups, and arylthio groups. group, an alkylsulfonyl group, an arylsulfonyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, a sulfamoyl group, a carbamoyl group, and a group that is a combination of these groups, and has two or more substituents. If so, these may be the same or different.

Examples of heterocyclic residues represented by R1 and R2 are:
Examples include pyridyl group, furyl group, thienyl group, virol group, and indolyl group. Further, this heterocyclic residue may have the same substituent as mentioned for the above-mentioned aryl group.

R1 is preferably an aryl group, a substituted aryl group, or a heterocyclic residue, and among these, a phenyl group, a substituted phenyl group, a naphthyl group, or a substituted naphthyl group is more preferable.

R2 is preferably an aryl group, a substituted aryl group, or a heterocyclic residue, and among these, a phenyl group, a substituted phenyl group, a naphthyl group, or a substituted naphthyl group is more preferable.

Although these compounds release or form acid at the temperatures required for thermal development, the rate of reaction can be varied over a wide range by varying R1 and R2°.

Another example of an effective acid precursor is:
It is a compound having a partial structure represented by the general formula [I[I]. However, the bonds at both ends of the partial structure of general formula [I[1] are bonded to carbon atoms.

-General formula [It[] Among the acid precursors having a partial structure represented by the above general formula [1], those which can be particularly advantageously used in the present invention are compounds represented by the following -general formula [rV].

- General formula [IV] In the formula, R3, R4 and n2 are each represented by the above-mentioned general formula [IV]
II] has the same meaning as R1, R2 and nl.

These compounds also release or form acid at the temperatures required for thermal development, but the reaction rate is slower than R3 and R3.
By changing 4, it is possible to make a wide range of changes.

Specific examples of acid precursors that can be used advantageously in the present invention are shown below. However, it is not limited to these.

(AP-1) (AP-2) (AP-3) (AP-4) (AP-5) (AP-8) (AP-9) (AP-10) (AP-11) (AP-12) (AP-13) (AP-14) (AP-15) (AP-16) (AP-17) (AP-20) (AP-21).

(AP-23) (AP-24) CH.

(AP-25) (AP-26) ○ (AP-27) CH.

(AP-28) (AP 29) (AP-30) (AP-31) r (AP-32) (AP-33) (AP-34) (AP-, 35) (AP-37) (AI'-38) (AP-39) (AP-41') sO,CH3 (AP-42) (AP-43) (AP-44) (AP-45) (AP-46) (AP-47) (AP-48) 0 (AP-49) (AP-50) (AP-52) (AP-53) (AP-54).

. ME\C1-1゜HOCH2CH,CN[(OCCH3 (AP-57) In addition, in the present invention, JP-A-49-58642, JP-A-50
An acid component that dissolves at 60° C. or higher or releases a volatile acid, such as those described in Japanese Patent No. 51452, can be used.

The amount of acid or acid precursor used in the present invention is:
- 0.01 to 100 g per 1 f per layer, preferably 0.05 to 20 (+).

The acids or acid precursors used in the present invention may be used alone or in combination of two or more.

When the heat-developable photosensitive material of the present invention is a color type, a dye-providing substance is used.

Dye-providing substances that can be used in the present invention will be explained below. The dye-donating substance may be any substance as long as it participates in the reduction reaction of the photosensitive silver halide and/or the organic silver salt used as necessary and can form or release a diffusible dye as a function of the reaction. Depending on the reaction type, negative dye-donors act on a positive function (i.e., form a negative dye image when negative-working silver halide is used) and positive dye-donors act on a negative function. dye-donor materials (that is, those that form a positive dye image when negative-working silver halide is used). Negative dye-donating substances are further classified as follows.

Releases a diffusible dye when oxidized Release type compound　　　Formation type compound Each dye-providing substance will be further explained.

Examples of the reducible dye-releasing compound include compounds represented by the general formula (2).

- General formula (2) % formula % In the formula, Car is a reducing substrate (so-called carrier) that is oxidized and releases a dye upon reduction of the photosensitive silver halide and/or the organic silver salt used as necessary. Yes, Dy
e is a diffusible dye residue.

Specific examples of the above-mentioned reducing dye-releasing compounds include JP-A-57-179840, JP-A-58-116537, and JP-A No. 58-116537.
No. 9-60434, No. 59-65839, No. 59-7
No. 1046, No. 59-87450, No. 59-8873
No. 0, No. 59-123837, No. 59-165054
No. 59-165055 and the specifications thereof, and examples thereof include the following compounds.

Exemplary dye-donor substances ■ OC18833fnl 0CI6H33 ■ IJ Shi16 k133 e [Phase]
) are listed.

In the formula, A1 and A2 each represent a hydrogen atom, a hydroxy group, or an amino group, and Dye is Dye represented by the general formula (2).
is synonymous with Specific examples of the above compounds are given in JP-A-59-12
This is shown in Japanese Patent No. 4329.

As the coupled dye-releasing compound, - general formula (4)
Examples include compounds represented by:

- General formula (4) % formula % In the formula, Cp+ is an organic group (so-called coupler residue) that can react with the oxidized form of the reducing agent to release a diffusible dye, and J is a bond of 2 The bond between CI)1 and J is cleaved by reaction with the oxidized form of the reducing agent. nl
represents O or 1, and Dye has the same meaning as defined in general formula (2). In addition, C1ot is preferably substituted with various ballast groups in order to make the coupled dye-releasing compound non-diffusible, and the ballast group has 8 or more carbon atoms ( more preferably 12 or more) organic groups, or hydrophilic groups such as sulfo groups and carboxy groups, or 8 or more (more preferably 12 or more) carbon atoms and hydrophilic groups such as sulfo groups and carboxy groups. It is a group that both have. Another particularly preferred ballast group can include polymer chains.

Specific examples of the compound represented by the above general formula (4) include JP-A-57-186744 and JP-A-57-122596.
No. 57-160698, No. 59-174834, No. 57-224883, No. 59-159159,
They are described in each specification of No. 59-231540, and include, for example, the following compounds.

Exemplary dye-donor coupling dye-forming compounds include -General formula (5)
Examples include compounds represented by:

- General formula (5) % formula %) In the formula, CCl2 is an organic group (so-called coupler residue) that can react with the oxidized form of the reducing agent (coupling reaction) to form a diffusible dye, F represents a divalent bonding group, and B represents a ballast group.

The coupler residue represented by Cp2 preferably has a molecular weight of 700 or less for the sake of diffusivity of the dye formed.
More preferably it is 500 or less.

Further, the ballast group is preferably the same as the ballast group defined in general formula (4), and particularly has 8 or more (more preferably 12 or more) carbon atoms and a hydrophilic group such as a sulfo group or a carboxy group. Groups having the same group are preferred, and polymer chains are more preferred.

The coupled dye-forming compound having a polymer chain is preferably a polymer having a repeating unit derived from a monomer represented by the general formula (6).

General formula (6) % formula %) In the formula, C1)2 and F have the same meaning as defined in general formula (5), Y represents an alkylene group, an arylene group, or an aralkylene group, and l is O or 1 and Z is 2
1i! j represents an organic group, and L represents an ethylenically unsaturated group or a group having an ethylenically unsaturated group.

Specific examples of the coupled dye-forming compounds represented by general formulas (5) and (6) include JP-A-59-1243
No. 39, No. 59-181345, No. 60-295
No. 0, Japanese Patent Application No. 59-179657, No. 59-1816
No. 04, No. 59-182506, No. 59-18250
It is described in each specification of No. 7, etc., and the following compounds are mentioned, for example.

Exemplary dye-donor polymer PM-1 M3 y: 60'i weight Chi IvX-5 H3 M x: Soz Kurachi PM-6y: 40tt weight C output M Ch M-8 NHCOCH2 M x: 50iii% y: 50!i% In the above general formulas (4), (5) and (6), CP
More specifically, the coupler group represented by t or CPz is preferably a group represented by the following formula.

General formula (7) - Formula (8) - Formula (9
) - Formula (10) General formula (11)
- Formula (12) General formula (13)
- Formula (14) - Formula (15)
- In the formula (16), R7, R8, R9 and RIO are each a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an acyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, Arylsulfonyl group, carbamoyl group, sulfamoyl group, acyloxy group, amino group, alkoxy group, aryloxy group, cyano group, alkylsulfonyl group, arylsulfonyl group, ureido group, alkylthio group, arylthio group, carboxy group, sulfo group or hetero Represents a ring residue, which further includes a hydroxyl group, a carboxy group, a sulfo group, an alkoxy group, a Siam L nitro group, an alkyl group, an aryl group, an aryloxy group, an acyloxy group, an acyl group, a sulfamoyl group, a carbamoyl group, an imido group, It may be substituted with a halogen atom or the like.

These substituents are selected depending on the purpose of CI)t and C92, and as mentioned above, in <C1ot, one of the substituents is preferably a ballast group, and in CO2, it is preferable to improve the diffusivity of the dye formed. The molecular weight is 70 to increase it.
Preferably, the substituents are selected to be 0 or less, more preferably 500 or less.

As a positive dye-donating substance, for example, the following formula (1
There is an oxidizable dye-releasing compound represented by 7).

General formula (17) In the formula, Wl represents a collection of atoms necessary to form a quinone ring (which may have a substituent on this ring),
R11 represents an alkyl group or a hydrogen atom, and E is -N-
C-+R13÷ (in the formula, R12 represents an alkyl group or a hydrogen atom, R13 represents an oxygen atom or R+2 represents -N-) or -302-, and r represents O
or 1, and Dye has the same meaning as defined in general formula (2). A specific example of this compound is JP-A-59-1
It is described in specifications such as No. 66954 and No. 59-154445, and includes, for example, the following compounds.

additional margin Great principle ■Fortune telling CH.

[Phase] As another positive dye-donor substance, the following formula (18)
There are compounds that lose their dye-releasing ability when oxidized, such as the compound represented by:

In the formula, W2 represents a collection of atoms necessary to form a benzene ring (which may have a substituent on the ring), and Ra
, r, E, and Q'ye have the same meanings as defined in general formula (17). A specific example of this compound is JP-A-59-1
No. 24327, No. 59-152440, etc., and include the following compounds.

Exemplary dye-donor substances ■ OCI-1.

[Phase] Still another positive dye-donor substance is represented by the following formula (
Examples include compounds represented by 19).

- Formula (19) In the above formula, W2, R11, and Dye are the general formula (18)
It has the same meaning as defined in .

Specific examples of this compound are described in JP-A-59-154445, etc., and include the following compounds.

Exemplary dye-providing substance ■ Besa No.2 General formula (2), (3), (4), (17) (18
) and (19), the residue of the diffusible dye represented by Dye will be explained in further detail. The residue of the diffusible dye preferably has a molecular weight of 800 or less, more preferably 600 or less, for the sake of the diffusibility of the dye;
Examples include residues such as azomethine dyes, anthraquinone dyes, naphthoquinone dyes, styryl dyes, nitro dyes, quinoline dyes, carbonyl dyes, and phthalocyanine dyes.

These dye residues may be in a temporary short-waveform form capable of multicoloring during heat development or during transfer. In addition, these dye residues are used for the purpose of increasing the light resistance of images, for example, in Japanese Patent Application Laid-Open No. 59
The chelatable dye residues described in No. 48765 and No. 59-124337 are also preferred.

These dye-providing substances may be used alone or in combination of two or more. The amount used is not limited, and depends on the type of dye-providing substance, whether it is used alone or in combination, or 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 types. It may be determined accordingly, but for example, the amount used is 0.005g to 50g per 1f, preferably 0.
．． 1 g to 10 g can be used.

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. Cresyl phosphate, etc.) and then subjected to ultrasonic dispersion, or dissolved in an alkaline aqueous solution (e.g., 10% sodium hydroxide aqueous solution, etc.) and then neutralized with mineral acid (e.g., hydrochloric acid or nitric acid, etc.). The photosensitive silver halides used in the present invention include silver chloride, odorant, etc. Examples include silver oxide, silver iodide, silver chlorobromide, silver chloroiodide, silver iodobromide, silver chloroiodobromide, and the like. The photosensitive silver halide can be prepared by any method in the photographic field, such as a single jet method or a double jet method. For example, by applying the method described in JP-A-54-48521, monodisperse silver halide grains can be obtained by the double jet method while keeping I) Ag constant. In this case, by appropriately selecting the time function of the addition rate, DH, 1)A(1, temperature, etc.), a highly monodisperse silver halide emulsion can be obtained.According to a roughly preferred embodiment, , a silver halide emulsion having silver halide grains having a shell can be used.The silver halide grains having a shell are prepared by using the method described above, and using silver halide grains having good monodispersity as a core, It can be obtained by sequentially growing shells on this.

The monodisperse silver halide emulsion used in the present invention refers to an emulsion having a particle size distribution in which the variation in the silver halide grain size contained in the emulsion is less than a certain percentage of the average grain size as shown below. .

Since the grain size distribution of an emulsion (hereinafter referred to as a monodisperse emulsion) consisting of a group of photosensitive silver halide grains with a uniform grain morphology and small variation in grain size is almost a normal distribution, the standard deviation can be easily determined. The width of the distribution of the silver halide grains involved is preferably 15% or less, more preferably monodispersity of 10% or less.

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 a silver halide emulsion comprising tabular silver halide grains having a large area and an aspect ratio, that is, a ratio of grain diameter to thickness 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 has not been fogged in advance, for example, U.S. Pat.
, No. 592,250, No. 3,206.313, No. 3.
No. 317.322, No. 3,511,682, No. 3,
No. 447.927, No. 3,761,266, No. 3
．． No. 703.584, No. 3.736.140, etc. (Silver halide grains have higher sensitivity inside the grain than the sensitivity on the surface. These internal latent images A method for producing a silver halide emulsion containing type silver halide is as described in the above-mentioned patent, for example, by first preparing AgCff1 grains and then adding bromide or a certain iodide to it to form a halide emulsion. A method of carrying out exchange, or a method of coating a central core of chemically sensitized silver halide with non-chemically sensitized silver halide, or a method of combining a chemically sensitized coarse grain emulsion with a chemically sensitized or chemically sensitized grain emulsion. Many methods are known, such as a method in which a fine grain emulsion is mixed with a coarse grain emulsion and a fine grain emulsion is placed on top of a coarse grain emulsion.
447.927 and 3,531,291, or silver halide emulsions having silver halide grains incorporating polyvalent metal ions, or U.S. Pat.
．． A silver halide emulsion in which the grain surface of silver halide grains containing a dopant is weakly chemically sensitized as described in JP-A No. 761.276, or a silver halide emulsion described in JP-A-5O-8524 and JP-A-50-38525, etc. Silver halide emulsions consisting of grains having a laminated structure, and other JP-A-52-
These include silver halide emulsions described in No. 156614 and JP-A-55-127549.

The light-sensitive silver halide emulsion may be chemically sensitized by any method known in the photographic art. Such sensitization methods include
Various methods include gold sensitization, sulfur sensitization, gold-sulfur sensitization, and reduction sensitization.

The silver halide in the above-mentioned photosensitive emulsion may be coarse or fine, but the preferred grain size is about 0.001 μm to about 1.5 μm, more preferably about 0.001 μm to about 1.5 μm, and more preferably about 0.001 μm to about 1.5 μm. .01 μm to about 0.5 μm.

The photosensitive silver halide emulsion prepared as described above can most preferably be applied to the heat-developable photosensitive layer which is a constituent layer of the photosensitive material of the present invention.

In the present invention, as another method for preparing photosensitive silver halide, it is also possible to allow a photosensitive silver salt-forming component to coexist with an organic silver salt described below to form photosensitive silver halide in a part of the organic silver salt. . The photosensitive silver salt-forming component used in this preparation method is an inorganic halide, specifically a halide represented by MXn (where M represents an H atom, an NH+ group, or a metal atom, and X represents (1! , Sr or I, n is 1 when M is an H atom or N84 group, and the valence when M is a metal atom.Metal atoms include lithium, sodium, potassium, rubidium, cesium, copper. , gold, beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, mercury, aluminum, indium, lanthanum, ruthenium, thallium, germanium, tin, lead, antimony, bismuth, chromium, molybdenum, tungsten, manganese, rhenium,
Examples include iron, cobalt, nickel, rhodium, palladium, osmium, iridium, platinum, and cerium.

), halogen-containing metal complexes (e.g., K2 Pt Cl1
s , K2 Pt 3r s , HAu C1,a
r.

(NH4>21r C4!s, (NH+)a lr
Cff1s.

(NH4)2 Rtl Cff1s, (NH4)3 R
IJ C16゜(NH4)2 Rh Cff1s, (N
H+ )3 Rh Sr s, etc.), onium halide (
For example, quaternary ammonium halides such as tetramethylammonium bromide, trimethylphenylammonium bromide, cetylethyldimethylammonium bromide, 3-methylthiazolium bromide, trimethylbenzylammonium bromide, and quaternary phosphants such as tetraethylphosphonium bromide. 3 such as onium halide, benzylethylmethylsulfonium bromide, 1-ethylthiazolium bromide
sulfonium halides, etc.), halogenated hydrocarbons (e.g., iodoform, bromoform, carbon tetrabromide, 2-
bromo-2-methylpropane, etc.), N-halogen compounds (N-chlorosuccinimide, N-bromosuccinimide, N-bromophthalimide, N-bromoacetamide, N-iodosuccinimide, N-bromophthalazinone, N-chlorophthalazinone, N-bromoacetanilide, N,N-dibromobenzenesulfonamide, N-bromo-N-methylbenzenesulfonamide, 1,3-dibromo-4,4-dimethylhydantoin, etc.), other halogen-containing Examples include compounds (eg, triphenylmethyl chloride, triphenylmethyl bromide, 2-bromobutyric acid, 2-bromoethanol, etc.).

These photosensitive silver halides and photosensitive silver salt forming components can be used in combination in various methods, and the amounts used are -
0.0011; 1 to 50 g per layer per 1f of support
It is preferable that it is, more preferably 0.1 g to 1
0 (l.

The heat-developable photosensitive material of the present invention has a multilayer structure including each layer sensitive to blue light, green light, and red light, that is, a heat-developable blue-sensitive layer, a heat-developable green-sensitive layer, and a heat-developable red-sensitive layer. You can also do that. Further, the same color photosensitive layer can be divided into two or more layers (for example, a high-sensitivity layer and a low-sensitivity layer).

In the above case, the blue-sensitive silver halide emulsion, green-sensitive silver halide emulsion, and red-sensitive silver halide emulsion used, respectively, can be obtained by adding various spectral sensitizing dyes to the silver halide emulsion. Can be done.

Typical spectral sensitizing dyes used in the present invention include, for example, cyanine, merocyanine, complex (trinuclear or tetranuclear) cyanine, holopolar cyanine, styryl, hemicyanine, oxonol, and the like. Among the cyanine dyes, those having a basic nucleus such as thiazoline, oxazoline, viroline, pyridine, oxazole, thiazole, selenazole, and imidazole are more preferred. Such nuclei include alkyl groups, alkylene groups,
It may contain a hydroxyalkyl group, a sulfoalkyl group, a carboxyalkyl group, an aminoalkyl group or an enamine group capable of forming a fused carbocyclic or heterocyclic ring. Further, it may be symmetrical or asymmetrical, and the methine chain or polymethine chain may have an alkyl group, a phenyl group, an enamine group, or a heterocyclic substituent.

In addition to the above-mentioned basic nucleus, merocyanine dyes have acidic nuclei such as thiohydantoin nucleus, O-danine nucleus, oxazolidione nucleus, thiazolidinedione nucleus, barbylic acid nucleus, thiazolinthione nucleus, malononitrile nucleus, and pyrazolone nucleus. It's okay.

These acidic nuclei may be further substituted with an alkyl group, an alkylene group, a phenyl group, a carboxyalkyl group, a sulfoalkyl group, a hydroxyalkyl group, an alkoxyalkyl group, an alkylamine group or a heterocyclic nucleus. If necessary, these dyes may be used in combination.

Furthermore, ascorbic acid derivatives, azaindene cadmium salts, organic sulfonic acids, etc., such as U.S. Pat. No. 2,933,3
A supersensitizing additive that does not absorb visible light, such as those described in Akira al1 of No. 90 and No. 2,937,089, can be used in combination.

The amount of these sensitizing dyes added is 1.times.10@-4 mol to 1 mol per mol of photosensitive silver halide or silver halide forming component. More preferably, 1×10→mol to l×10
``It's a mole.

In the heat-developable photosensitive material of the present invention, various organic silver salts can be used, if necessary, for the purpose of increasing sensitivity and improving developability.

Examples of organic silver salts used in the heat-developable photosensitive material of the present invention include those disclosed in Japanese Patent Publication Nos. 43-4921, 52626-1980, 141222-1982, 36224-1983, and 37610-1980, etc. Long-chain aliphatic carboxylic acids as described in each publication and specifications such as U.S. Patent Nos. 3,330,633, 3,794,496, and 4,105,451 Silver salts of carboxylic acids having heterocycles, such as silver laurate, silver myristate, silver valmitate, silver stearate, silver arachidonate, silver behenate, silver α-(1-phenyltetrazolthio)acetate etc., silver aromatic carboxylates, such as silver benzoate, silver phthalate, etc., Japanese Patent Publication No. 44-26582, No. 4
No. 5-12700, No. 45-18416, No. 45-2
No. 2185, JP-A-52-137321, JP-A-58
There are silver salts of imino groups described in publications such as No.-118638, No. 58-118639, and U.S. Pat. No. 4,123,274.

Examples of silver salts of imino groups include benztriazole silver. The penztriazole silver may be substituted or unsubstituted. Representative examples of substituted benztriazole silver include, for example, alkyl-substituted benztriazole silver (preferably a C22 or less alkyl group,
More preferably, those substituted with an alkyl group of C4 or less, such as silver methylbenztriazole, silver ethylbenztriazole, silver n-octylbenztriazole, etc.), silver alkylamide benztriazole (preferably substituted with an alkylamide group of 022 or less) silver acetamidobenztriazole, silver propionamidebenztriazole, silver 1so-butylamidebenztriazole, silver laurylamidebenztriazole, etc.), silver alkylsulfamoylbenztriazole (preferably silver fluorylsulfamoyl with C22 or less). )I;
those substituted with groups, such as 4-(N,N-diethylsulfamoyl)penztriazole silver, 4-N-
propylsulfamoyl)penztriazole silver, 4-
(N-octylsulfamoyl)penttriazole silver, 4-(N-decylsulfamoyl)benztriazole silver, 5-(N-octylsulfamoyl)penttriazole silver, etc.), halogen-substituted benztriazole silver salts (for example, 5-chlorobenztriazole silver, 5-bromobenztriazole silver, etc.), alkoxybenztriazole silver (preferably substituted with an alkoxy group of 022 or less, more preferably C + J: J, alkoxy group below), For example, 5-methoxybenztriazole silver,
5-ethoxybenztriazole silver, etc.), 5-nitrobenztriazole silver, 5-aminobenztriazole silver, 4-hydroxybenztriazole silver, 5-carboxybenztriazole silver, 4-sulfobenztriazole silver, 5-sulfobenztriazole silver etc.

Examples of other silver salts having an imino group include imidazole silver, benzimidazole silver, 6-nidropenzimidazole silver, pyrazole silver, urazole silver, 1.2
．． 4-1-Riazole silver, 1H-tetrazole silver, 3-
Amino-5-benzylthio-1,2,4-triazole silver, saccharin.

Silver salts of other mercapto compounds such as silver, phthalazinone silver, phthalimide silver, etc., such as 2-mercaptobenzoxazole silver, mercaptooxadiazole silver, 2-mercaptobenzothiazole silver, 2-mercaptobenzimidazole silver, 3-mercapto-4- phenyl-1,2,
4-triazole silver, 4-hydroxy-6-methyl-1
, 3°38.7-titrazaindene silver and 5-methyl-7-hydroxy-1,2,3,4,6-pentazaindene silver.

Other silver complex compounds with a stability constant of 4.5-10.0 as described in JP-A No. 52-31728, imitation compounds as described in U.S. Pat. A silver salt of dacilinthion is used.

Among the above organic silver salts, imino group silver salts are preferred;
Particularly preferred are silver salts of benzotriazole derivatives, more preferably 5-methylbenzotriazole 6 and its derivatives, sulfobenzotriazole and its derivatives, and N-alkylsulfamoylbenzotriazole and its derivatives.

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

Moreover, the method for preparing the organic silver salt is -numerically water or aqueous!
This method involves dissolving and mixing silver nitrate and raw material organic compounds in a solvent, but if necessary, a binder may be added or
It is also effective to add an alkali such as sodium hydroxide to promote dissolution of the organic compound, or to use an ammoniacal silver nitrate solution.

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.

As the reducing agent used in the photothermographic material of the present invention, those commonly used in the field of photothermographic materials can be used.

The dye-providing substance used in the heat-developable photosensitive material of the present invention is, for example, JP-A-57-186744;
-79247, 58-149046, 58
-149047, 59-124339, 5
In the case of a dye-donating substance that releases or forms a diffusible dye by coupling with an oxidized form of a reducing agent such as those disclosed in No. 9-181345 and No. 60-2950, the present invention Examples of reducing agents used in
61,270, 3.764.328 specifications,
Also, RD No. 12146, No. 0.1510
8, No. 15127 and JP-A-56-2713
p-phenylenediamine type and p-
Aminophenol-based developing agents, phosphoramidophenol-based developing agents, sulfonamide phenol-based developing agents, sulfonamide aniline-based developing agents, hydrazone-based color developing agents, and the like can be used. Also, US patent 3,
342,599, 3.719.492, JP-A-53-135628, and JP-A-57-79035, etc., the color developing agent breaker, etc. can also be used advantageously.

As a particularly preferable reducing agent, JP-A-56-146133
Examples include reducing agents represented by the following formula (1) described in the No.

General formula (1) % formula % In the formula, R1 and R2 represent a hydrogen atom or an alkyl group having 1 to 30 carbon atoms (preferably 1 to 4) that may have a substituent, and R1 and R2 represent may be closed to form a heterocycle. R3, R4゜R5, t5 and R6 are a hydrogen atom, a halogen atom, a hydroxy group, an amiLL alkoxy group, an acylamido group, a sulfonamide group, an alkylsulfonamide group, or a carbon atom number of 1 to 30 that may have a substituent. (preferably 1 to 4) alkyl group;
R3 and R1 and R5 and R2 may each be ring-closed to form a heterocycle. M represents an alkali atom, an ammonium group, a nitrogen-containing organic base, or a compound containing a quaternary nitrogen atom.

The nitrogen-containing species base in the above formula (1) is an organic compound containing a nitrogen atom that exhibits basicity capable of forming an inorganic salt and a salt, and particularly important species bases include amine compounds. Chain amine compounds include primary amines, secondary amines, tertiary amines, etc., and cyclic amine compounds include lysine, quinoline, piperidine, etc., which are well-known examples of typical heterocyclic organic bases. , imidazole and the like. In addition, compounds such as hydroxylamine, hydrazine, and amidine are also useful as chain amines. Further, as the salt of the nitrogen-containing organic base, the above-mentioned non-silicate salts of solid bases (for example, salt M salt, sulfur M salt, nitrate, etc.) are preferably used.

On the other hand, the compound containing quaternary nitrogen in the above formula is 4! Salts or hydroxyl compounds of nitrogen compounds having a covalent bond of i can be mentioned.

Next, preferable specific examples of the reducing agent represented by the above-mentioned formula (1) are shown below.

(R-5) (R-8) ("jl (R-9) (R-10) (R-11) (R-12) H (R-') ('1) H3 (1a-24) ( Fl, -21) (R-22) (R-23) (R-25) (R-26> (R-27) (R-28) (R-29) (R-30) )IJbarrogant-J The reducing agent represented by the above-mentioned formula (1) can be obtained by a known method,
For example, Houben Peil, Mesosden der Organitsien Hemi, Band XI/2 (Houben
-Weyl, Methoden der Organ
ischen Chemie, Band X I
/2) It can be synthesized according to the method described on pages 645-703.

Furthermore, it is also possible to use two or more of the above-mentioned reducing agents at the same time, or to use a black and white developing agent described below in combination for the purpose of increasing developability.

Further, the dye-donating substance used in the present invention is JP-A No. 57-179840, No. 58-58543, No. 5
In the case of compounds that release dyes upon oxidation, compounds that lose their ability to release dyes when oxidized, compounds that release dyes when reduced, etc. as shown in Nos. 9-152440 and 59-154445, etc. Alternatively, in the case where only a silver image is simply obtained, a developing agent as described below can also be used.

For example, phenols (e.g. p-phenylphenol, p-methoxyphenol, 2,6-tert-
butyl-p-cresol, N-methyl-p-aminophenol, etc.), sulfonamidophenols [e.g. 4-
Benzenesulfonamidophenol, 2-benzenesulfonamidophenol, 2.6-dichloro0-4-benzenesulfonamidophenol, 2.6-dipromo4-
(p-toluenesulfonamide)phenol, etc.], or polyhydroxybenzenes (e.g., hydroquinone,
tert-butylhydroquinone, 2,6-dimethylhydroquinone, chlorohydroquinone, carboxyhydroquinone, catechol, 3-carboxycatechol, etc.), naphthols (e.g. α-naphthol, β-naphthol, 4-aminonaphthol, 4-methoxynaphthol, etc.) ), hydroxybinaphthyls and methylene bisnaphthols [e.g. 1,1'-dihydroxy-2,2'
-binaphthyl, 6,6'-dibromo-2,2'-dihydroxy-1,1'-binaphthyl, 6,6-sinitro 2
．． 2'-dihydroxy-1,1'-binaphthyl, 4,4
'-dimethoxy-1,1'-dihydroxy-2,2'-
binaphthyl, bis(2-hydroxy-1-naphthyl)methane, etc.], methylene-sphenols [e.g. 1,1-
Bis(2-hydroxy-3,5-dimethylphenyl)-
3゜5.5-trimethylhexane, 1,1-bis(2-
Hydroxy-3-tert-butyl-5-methylphenyl)methane, 1,1-bis(2-hydroxy-3,5-
di-tert-butylphenyl)methane, 2,6-methylenebis(2-hydroxy-3-tert-butyl-5
-methylphenyl)-4-methylphenol, α-phenyl-α, α-bis(2-hydroxy-3-tert-
Butyl-5-methylphenyl)methane, 1,1-bis(
2-hydroxy-3,5-dimethylphenyl)-2-methylpropane, 1,1,5,5-tetrakis(2-hydroxy-3,5-dimethylphenyl)-2,4-ethylpentane, 2,2 -bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3-methyl-5-tert-butylphenyl)
propane, 2,2-bis(4-hydroxy-3,5-di-tert-butylphenyl)propane, etc.], ascorbic acids, 3-pyrazolidones, pyrazolones, hydrazones, and paraphenylenediamines.

These developing agents mentioned above can also be used alone or in combination of two or more.

The amount of the reducing agent used in the heat-developable photosensitive material of the present invention depends on the type of photosensitive silver halide, the type of organic acid silver salt, and the type of other additives used, but usually is 0.01 per mole of photosensitive silver halide
~1500K, preferably 0.1~20
It is 0 mole.

Examples of the binder used in the heat-developable photosensitive material of the present invention include synthetic or natural polymers such as polyvinyl butyral, polyvinyl acetate, ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinylpyrrolidone, gelatin, and phthalated gelatin. One or more molecular substances can be used in combination. 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 the following binder described in JP-A-59-229556.

This binder includes gelatin and vinylpyrrolidone polymer. The vinylpyrrolidone polymer may be polyvinylpyrrolidone, which is a homopolymer of vinylpyrrolidone, or a copolymer (including a graft copolymer) of vinylpyrrolidone and one or more other monomers copolymerizable with vinylpyrrolidone. ). These polymers can be used regardless of their degree of polymerization. Polyvinylpyrrolidone may be substituted polyvinyl and lolidone, and preferred polyvinylpyrrolidone has a molecular weight of 1□000 to 40
It is of 0.000. Other monomers copolymerizable with vinylpyrrolidone include (meth)acrylic acid esters such as acrylic acid, methacrylic acid and alkyl esters thereof, vinyl alcohols, vinyl acetates,
Examples include vinyl monomers such as vinyl imidazoles, (meth)acrylamides, vinyl carbinols, and vinyl alkyl ethers, but at least 20% (by weight, same hereinafter) of the composition ratio must be polyvinylpyrrolidone. is preferred. Preferred examples of such copolymers are those having a molecular weight of s,ooo to 400,000.

The gelatin may be lime-treated or acid-treated, and may be ossein gelatin, big skin gelatin, hydrogelatin, or modified gelatin obtained by esterifying or phenylcarbamoylating these gelatins.

In the above binder, gelatin preferably accounts for 10 to 90% of the total binder amount, more preferably 20 to 60%, and vinylpyrrolidone accounts for 5 to 90%.
It is preferably 10 to 80%, more preferably 10 to 80%.

The binder may contain other polymeric substances,
Gelatin and a mixture of polyvinylpyrrolidone with a molecular weight of 1,000 to 400.000 and one or more other polymeric substances, gelatin and a molecular weight of s, ooo to 400.00
A mixture of 0 vinylpyrrolidone copolymer and one or more other polymeric substances is preferred. Other polymeric substances used include polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyvinyl butyral,
Examples include polyethylene glycol, polyethylene glycol ester, or proteins such as cellulose derivatives, and natural substances such as polysaccharides such as starch and gum arabic. These are 0-85%, preferably 0-70%
May be included.

Note that the vinyl pyrrolidone polymer may be a crosslinked polymer, but in this case, it is preferable to crosslink it after coating it on the support (including the case where the crosslinking reaction progresses by leaving it to stand).

The amount of binder used is usually 0.05g to 50g per layer per 1f of support, preferably 0.1g to 1g.
It is 10g.

In addition, the binder is 0.1% per 1g of the dye-providing substance.
It is preferable to use ~10 g, and examples of the support used in the photothermographic material of the present invention are more preferably polyethylene film, cellulose acetate film and polyethylene terephthalate film, synthetic plastic films such as polyvinyl chloride, photographic base paper, Examples include paper supports such as printing paper, baryta paper, and resin coated paper, as well as supports obtained by coating and curing an electron beam curable resin composition on these supports.

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 used in the present invention is a compound that promotes thermal development and/or thermal transfer. Regarding these compounds, for example, U.S. Pat. No. 3,347,675, U.S. Pat.
556, Japanese Patent Application No. 59-47787, etc., and those particularly useful in the present invention include urea derivatives (e.g., dimethylurea, diethylurea, phenylurea). ), amide derivatives (e.g., acetamide, benzamide, etc.)
, polyhydric alcohols (for example, 1.5-bentanediol, 1.6-bentanediol, 1.2-cyclohexanediol, pentaerythritol, trimethylolethane, etc.), or polyethylene glycols.

Among the above thermal solvents, water-insoluble solid thermal solvents described below are more preferably used.

A water-insoluble solid thermal solvent is a compound that is solid at room temperature but becomes liquid at high temperatures (60°C or higher, preferably 100°C or higher, particularly preferably 130°C or higher and 250°C or lower), and is an inorganic/organic The sex ratio (“Yoshio Koda, Sankyo Publishing, 1984)” is in the range of 0.5 to 3.0, preferably 0.7 to 2.5, particularly preferably 1.0 to 2.0. A compound with a solubility in water at room temperature of less than 1.

Specific examples of water-insoluble solid thermal solvents are shown below. Examples of water-insoluble solid thermal solvents Melting point (°C) Inorganic/Organic C(c9.)3CONH214F 1.44 Melting point (°C) Inorganic/Organic ○ ÷C0CONH0151~153° 154CH3C
ONHa←<=)-NHCOCH, 290° or more
134aCI(2CONHz 156° 1
34GCONH(CHz)aNHcOno 152~15
4° 1260-CONH 166° 0,88
CHsOGCONH2164~167' 1.47 Melting point (C) Melting point ("C)
Inorganic/Organic CH3-CI)602NHC2H4NH30za-CH
s 168° 159 Many compounds used as water-insoluble solid heat solvents are commercially available, and can be easily synthesized by those skilled in the art.

The method of adding the water-insoluble hot solvent is not particularly limited, but it may be added by grinding and dispersing it using a ball mill, sand mill, etc.
There are methods such as adding it by dissolving it in an appropriate solvent, and adding it as an oil-in-water dispersion by dissolving it in a high boiling point solvent.
It is preferable to pulverize and disperse the solid particles using a ball mill, sand mill, etc. and add them while maintaining the solid particle shape.

Layers to which the water-insoluble homogeneous thermal 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, and the like, so that the respective effects can be obtained.

The amount of the water-insoluble heat solvent added is usually 10% to 500% by weight, preferably 50% to 300% by weight of the binder.

Note that even when the melting point of the water-insoluble solid thermal solvent of the present invention is higher than the thermal development temperature, the melting point is lowered by being added to the binder, so that it can be effectively used as a thermal solvent.

The photothermographic material of the present invention may contain various additives in addition to the above-mentioned components, if necessary.

For example, melt formers such as acetamide and succinimide described in U.S. Patent No. 3,438,776; compounds such as polyalkylene glycols described in U.S. Pat. , -C〇-1-8O2- described in U.S. Patent Box 3,667.959
There are non-aqueous polar organic compounds having a melting point of 20° C. or higher, such as lactone having 1-so-g.

Benzophenone derivatives described in Zarani JP-A-49-115540, JP-A-53-24829, JP-A-53-
Phenol derivatives described in No. 60223, JP-A-5
Carboxylic acids described in No. 8-118640, polyhydric alcohols described in JP-A-58-198038,
Also included are sulfamoylamide compounds described in JP-A-59-84236.

Further, a color toning agent known in heat-developable photosensitive materials may be added as a development accelerator to the photothermographic material of the present invention. As a color toning agent, for example, JP-A-46-4
No. 928, No. 46-6077, No. 49-5019,
49-5020, 49-91215, 4
No. 9-107727, No. 50-2524, No. 50-
No. 67132, No. 50-67641, No. 50-11
No. 4217, No. 52-33722, No. 52-9981
No. 3, No. 53-1020, No. 53-55115,
No. 53-76020, No. 53-125014, No. 5
No. 4-156523, No. 54-156524, No. 5
No. 4-156525, No. 54-156526, No. 5
No. 5-4060, No. 55-4061, No. 55-32
Publications such as No. 015 and West German patent 2.140.40
No. 6, No. 2.147゜063, No. 2,220,61
No. 8, U.S. Patent Box 3.847.612, U.S. Patent No. 3.78
2.941, 4,201,582 and JP-A-57-207244, 57-207245, 5
Phthalazinone, phthalimide, pyrazolone, quinazolinone, N-hydroxynaphthalimide, benzoxazine, naphthoxazinedione, 2,3-dihydro- Phthalazinedione, 2.3
-dihydro-1,3-oxazine-2,4-dione, oxypyridine, aminopyridine, hydroxyquinoline,
Aminoquinoline, isocarbostyryl, sulfonamide, 2) 1-1,3-bendithiazine-2,4-(3H)
dione, benzotriazine, mercaptotriazole,
dimercaptotetrazabentalene, aminomercaptotriazole, acylaminomercaptotriazoles,
phthalic acid, naphthalic acid, phthalamic acid, etc.; a mixture of one or more of these with an imidazole compound; and a mixture of at least one acid or acid anhydride such as phthalic acid, naphthalic acid, etc. and a phthalazine compound; Further examples include combinations of phthalazine and maleic acid, itaconic acid, quinolinic acid, gentisic acid, and the like.

Antifoggants include, for example, U.S. Patent Box 3,645;
Higher aliphatic compounds (e.g. behenic acid, stearic acid, etc.) described in No. 739, mercuric salts described in Japanese Patent Publication No. 11113/1983, and N-
Halogen compounds (e.g. N-halogenoacetamide, N
-A O genosuccinimide, etc.), U.S. Patent Boxes 3 and 7
00,457, mercapto compound-releasing compounds described in JP-A No. 51-50725, arylsulfonic acids (e.g. benzenesulfonic acid, etc.) described in JP-A No. 49-125016, carboxylic acids described in JP-A No. 51-47419. Lithium salts (e.g. lithium laurate), British Patent No. 1,
455,271, oxidizing agents (e.g. perchlorates, inorganic peroxides, persulfates, etc.) described in JP-A-50-101.019, sulfinic acids or thiosulfonic acids described in JP-A-53-19825. , 2-thiouracils described in Shu 51-3223, simple sulfur described in Shu 51-26019, Shu 51-42529, Shu 51-8112
No. 4, disulfide and polysulfide compounds described in No. 55-93149, rosin or diterpenes (e.g. abietic acid,
pimaric acid, etc.), polymer acids having free carboxyl groups or sulfonic acid groups as described in IEl 51-104338, thiazolinthione as described in U.S. Patent No. 4,138,265, JP-A-54-51821, 1,2,4-triazole or 5-mercapto-1,2,4-triazole described in U.S. Patent No. 4.137.079; thiosulfinate esters described in U.S. Patent No. 55-14-0833; 1.2 described in No.-142331
．． 3.4-Thiatriazoles, dihalogen compounds or trihalogen compounds described in No. 59-46641, No. 59-57233, and No. 59-57234, and thiol compounds described in No. 59-111636. .

In addition, as other antifoggants, Japanese Patent Application No. 59-565
Hydroquinone derivatives described in No. 06 (for example, G.C.
-octylhydroquinone, dodecanylhydroquinone, etc.) or hydroquinone derivatives described in Japanese Patent Application No. 59-66380, and benzotriazole derivatives (e.g., 4-sulfobenzotriazole, 5-carboxybenzotriazole, etc.) are preferably used in combination. can.

As a silver image stabilizer, U.S. Patent Box 3.707.37
The polyhalogenated organic oxidizing agent (e.g., tetrabromobutane, tribromoquinaridine, etc.) described in No. 7 Mei 1B1,
5- described in Belgian Patent No. 768.071 Mei IB
Methoxycarbonylthio-1-phenylated, lutetrazole, monohalo compounds described in JP-A-50-119624 (e.g., 2-bromo-2-tolylsulfonylacetamide, etc.), bromine compounds described in JP-A-50-120328 (For example, 2-bromomethylsulfonylbenzothiazole, 2,4-bis(tribromomethyl)-6-methyltriazine, etc.), and tribromoethanol described in JP-A-53-46020. Also, various monohalogenated organic antifoggants for silver halide emulsions as described in JP-A-50-119624 can be used.

Other image stabilizers include U.S. Patent Box 3,220;
No. 846, No. 4.082.555, No. 4.088
．． No. 496, JP-A-50-22625, Research Disclosure (RD) No. 12021, 15
No. 168, No. 15567, No. 15732, No. 1
Compounds called activator precursors that release basic substances by heat, such as compounds such as guanidinium trichloroacetate that release bases by decarboxylation with heat, as described in No. 5733, No. 15734, and No. 15776, etc.; Galactonamide; Compounds such as fludonamide-based compounds, amine imides, 2-carboxycarboxamides, etc., as well as sodium phosphate-based base generators described in JP-A-56-130745 and JP-A-56-132332, British Patent No. 2,079 Compounds that generate amines through intramolecular nucleophilic reactions described in JP-A No. 59-157637, hydroxamic acid carbamates described in JP-A No. 59-166943, etc. No. 59-180537,
Examples include base releasing agents described in Japanese Patent No. 59-174830 and Japanese Patent No. 59-795237.

Additionally, U.S. Patent Nos. 3,301,678 and 3,506
, No. 444, No. 3,824,103, No. 3.844
．． Illithiuronium compounds, S-rubamoyl derivatives of mercapto-containing compounds, and nitrogen-containing heterocyclic compounds described in RD No. 788, RD 12035, RD 18016, etc. may be used for the purpose of stabilizing images. Patent No. 3.669.670, Patent No. 4,012,260,
No. 4,060,420, No. 4,207,392, R
D 15109j3, the activator stabilizer described in RD17711, etc., and nitrogen-containing organic bases called activator stabilizers and riser precursors, such as α-sulfonylacetate of 2-aminothiazoline or trichloroacetic acid Pa salt, and acylhydrazine compounds, etc., are developed respectively. It can be used for the purpose of promoting the image, or for the purpose of stabilizing the image.

Also, for example, JP-A-56-130745 and JP-A-59-2
18443, in the presence of a small amount of water (or by spraying a small amount of water before heating, -
You can supply water by applying a fixed amount, or use the U.S. patent tube 3,
312,550 and the like, development may be carried out using hot steam, hot air containing moisture, or the like. Also, compounds that release water into heat-developable photosensitive materials, such as Japanese Patent Publication No. 44-26
Compounds containing water of crystallization such as those described in No. 582, such as sodium phosphate dodecahydrate and ammonium alum diquadrate, may be incorporated into the photothermographic material.

In addition, various additives such as antihalation dyes, optical brighteners, hardeners, antistatic agents, plasticizers, and spreading agents, coating aids, and the like may be used.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or a non-photosensitive layer (for example,
Colloidal silica can be used for the undercoat layer, intermediate layer, protective layer, etc.).

The colloidal silica used in the present invention is mainly a colloidal solution of silicic anhydride with an average particle size of 3 to 1201μ using water as a dispersion medium, and the main component is 5iO2 (silicon dioxide).
It is. Regarding colloidal silica, for example, JP-A-56-109336, JP-A-53-123916, JP-A-5
It is described in No. 3-112732, No. 53-100226, etc. The amount of colloidal silica used is 0.05 to 0.05 to the binder of the layer to be mixed and coated in terms of dry weight ratio.
A range of 2.0 is preferred.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or a non-photosensitive layer (for example,
An organic fluoro compound can be used for the undercoat layer, intermediate layer, protective layer, etc.).

Regarding the organic fluoro compounds used in the present invention, US Patent No. 3,589,906 and US Pat.
No. 3.754.924, No. 3,775,126, No. 3,850,640, West German Patent Publication No. 1,942
, No. 665, No. 1,961,638, No. 2,124,
No. 262, British Patent Box No. 1,330,356, Belgian Patent No. 742.680 and JP-A-46-7781, No. 48-9715, No. 49-46733, No. 49
-133023, Shu 50-99529, Shu 50-1
No. 1322, No. 50-160034, No. 51-431
No. 31, No. 51-129229, No. 51-10641
No. 9, No. 53-84712, No. 54-111330
No. 5B-109336, No. 59-30536, No. 59-45441 and Japanese Patent Publications No. 47-9303, No. 48-43130, No. 59-5887, etc., and these compounds can be preferably used.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or
Alternatively, an antistatic agent can be used in a non-photosensitive layer (for example, an undercoat layer, an intermediate layer, a protective layer, etc.).

As the antistatic agent used in the present invention, British Patent Box 1
, No. 466.600, Research Disclosure t-
(Research [)isclosure)
15840, 162513, 16630, U.S. Patent Nos. 2,327,828, 2,861,056
No. 3,206,312, No. 3.245.833, No. 3.428.451, No. 3.775.126,
3.963.498, 4.025.342,
4,025,463, 4,025.691,
Compounds described in 4.025.704 etc. are mentioned,
These can be preferably used.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or
Alternatively, an ultraviolet absorber can be used in a non-photosensitive layer (for example, an undercoat layer, an intermediate layer, a protective layer, etc.).

Examples of the ultraviolet absorber used in the present invention include benzophenone compounds (for example, those described in JP-A No. 46-2784, U.S. Pat. No. 3,215,530, and U.S. Pat. , US Patent 4
．． 045.229), 4-thiazolidone compounds (e.g., those described in U.S. Pat. No. 3,314,794, U.S. Patent No. 3,352. For example, Special Publication No. 36-10466, No. 41-1687, No. 42
-26187, 44-29620, 48-41
572, JP-A No. 54-95233, JP-A No. 57-142
No. 975, U.S. Patent No. 3,253,921, No. 3,5
33,794, 3,754,919, 3.
No. 794.493, No. 4, No. 009.038, No. 4,2
No. 20.711, No. 4.323.633, Research
Disclosure (Research Disclosure)
ure) No. 22519, benzoxidol compounds (e.g., U.S. Patent No. 3.700.4)
55), cinnamate ester compounds (for example, U.S. Pat. No. 3.705.805, U.S. Pat. No. 3.707.
No. 375 and JP-A No. 52-49029). Additionally, U.S. Patent No. 3,499.
762 and JP-A-54-48535 can also be used. UV-absorbing couplers (e.g.
α-naphthol cyan dye-forming couplers) and ultraviolet-absorbing polymers (e.g., JP-A-58-11194
No. 2, No. 178351, No. 181041, No. 59-
19945@, No. 23344, and those described in the official gazette).

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or
Alternatively, a hardening agent can be used in a non-photosensitive layer (for example, an undercoat layer, an intermediate layer, a protective layer, etc.).

Hardeners used in the present invention include aldehyde-based and aziridine-based hardeners (for example, PB Report 19,921, U.S. Patent No. 2,950.197, U.S. Patent No. 2.964.404).
No. 2,983,611, No. 3,271,17
5 of Mei IB, Japanese Patent Publication No. 46-40898, and Japanese Patent Publication No. 50-91315), isoxazole series (for example, those described in U.S. Pat. No. 331, 609) ), epoxy systems (e.g. U.S. patent 3
, 047, 394, West German Patent No. 1, 085, 66
No. 3, the specifications of British Patent No. 1,033,518, those described in Japanese Patent Publication No. 48-35495), vinyl sulfone systems (for example, PB Report 19,920, West German Patent No. 1.100.942) No. 2,337,412, No. 2,545,722, No. 2,635,518,
No. 2.742.308, No. 2.749.280, British Patent No. 1,251,091, Patent Application No. 1974-5423
No. 6, No. 48-110996, U.S. Pat. No. 3,539
．． No. 644 and No. 3,490,911 of each Mei 11! (described in the book), acryloyl type (for example,
-27949, U.S. Patent No. 3.640.720), carbodiimide type (e.g., U.S. Patent No. 2.938.892, U.S. Patent No. 4,043,818)
No. 4,061.499, each specification, Special Publication No. 1973-
No. 38715, those described in Japanese Patent Application No. 15095/1983), triazine type (for example, West German Patent No. 2,
No. 410,973, No. 2.553.915, and U.S. Patent No. 3.325.287 [Book 1, Japanese Patent Application Laid-open No. 1983-1989]
12722), maleimide-based, acetylene-based, methanesulfonic acid ester-based, and N-methylol-based hardeners can be used alone or in combination. As a useful combination technique, for example, West German Patent No. 2,
No. 447,587, No. 2,505.746, No. 2,5
No. 14,245, U.S. Pat. No. 4,047,957, U.S. Patent No. 3.832.181, and U.S. Pat. ll book, JP-A-48-43319, JP-A No. 50-63
No. 062, No. 52-127329, Special Publication No. 1977-32
Examples include combinations described in each publication of No. 364.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or
Alternatively, a polymeric hardener can be used in a non-photosensitive layer (for example, one undercoat layer, intermediate layer, protective layer, etc.).

Examples of the polymeric hardening agent used in the present invention include polymers having aldehyde groups (e.g., copolymers of acrolein, etc.) described in U.S. Patent No. 3,396,029.
, No. 3,362,827, Research Disclosure No. 17333 (197g), etc. Polymers having dichlorotriazine groups, U.S. Patent No. 3.623
．． Polymers having epoxy groups as described in No. 878, Research Disclosure No. 16725 (1978)
, U.S. Patent No. 4,161,407, JP-A-54-65
Examples include polymers having an active vinyl group or a group that can be a precursor thereof, as described in JP-A-56-66841, and polymers having an active ester group as described in JP-A No. 56-66841. .

In the heat-developable photosensitive material of the present invention, a polymer latex is used in the heat-developable photosensitive layer and/or the non-photosensitive layer (e.g., undercoat layer, intermediate layer, protective layer, etc.) for the purpose of improving the physical properties of the film. be able to.

Preferred specific examples of the polymer latex used in the present invention include polymethyl acrylate, polyethyl acrylate, polylobyl acrylate, a copolymer of ethyl acrylate and acrylic acid, a copolymer of vinylidene chloride and butyl acrylate, and a copolymer of butyl acrylate and acrylic acid. , a copolymer of vinyl acetate and butyl acrylate, a copolymer of vinyl acetate and ethyl acrylate, a copolymer of ethyl acrylate and 2-acrylamide, and the like.

The preferred average particle size of the polymer latex is 0.02 μm
~0.2 μl. The amount of polymer latex used is 0.0 in dry weight ratio to the binder of the added layer.
3 to 0.5 is preferred.

In the heat-developable photosensitive material of the present invention, various surfactants are added to the heat-developable photosensitive layer and/or non-photosensitive layer (e.g., undercoat layer, intermediate layer, protective layer, etc.) for the purpose of improving coating properties. Agents can be used.

The surfactant used in the present invention may be any of anionic, cationic, amphoteric and nonionic surfactants.

Examples of anionic surfactants include alkyl carboxylates, alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl liiiIi! Carboxy groups such as esters, alkyl phosphates, N-acyl-N-furkyltaurines, sulfosuccinates, sulfoalkyl polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl phosphates, etc. , a sulfo group, a phosphor group, a sulfuric acid ester group, a phosphoric acid ester group, and other acidic groups are preferred.

Examples of cationic surfactants include alkylamine salts, aliphatic or aromatic quaternary ammonium salts,
Heterocyclic quaternary ammonium salts such as pyridinium and imidazolium, and phosphonium or sulfonium salts containing aliphatic or heterocyclic rings are preferred.

Preferred examples of the amphoteric surfactant include amino acids, aminoalkyl sulfonic acids, aminoalkyl sulfates or phosphoric esters, alkyl betaines, and amine oxides.

Examples of nonionic surfactants include saponin (steroid type), alkylene oxide derivatives (such as polyethylene glycol, polyethylene glycol/polypropylene glycol condensates, polyethylene glycol alkyl ethers or polyethylene glycol alkylaryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters,
polyalkylene glycol alkylamines or amides, polyethylene oxide adducts of silicone),
Preferred are glycidol derivatives (eg, alkenylsuccinic acid polyglycerides, alkylphenol polyglycerides), fatty acid esters of polyhydric alcohols, alkyl esters of sugars, and the like.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or a non-photosensitive layer (for example, an undercoat layer, an intermediate layer, etc.) for the purpose of improving developability, improving image dye transferability, improving optical properties, etc. ,
(protective layer, etc.) may contain non-photosensitive silver halide grains.

The non-photosensitive silver halide grains used in the present invention may have any silver halide composition such as silver chloride, silver bromide, silver iodide, silver iodobromide, silver chlorobromide, silver chloroiodobromide, etc. Can be used. The preferred grain size of the non-photosensitive silver halide grains is about 0.
．． It is 3 μm or less.

Also, the amount added is 0.00% in terms of silver amount for the layer to be added.
The range is preferably from 02 to 3111/l''.

The heat-developable photosensitive material of the present invention includes a heat-developable photosensitive layer and/or a non-photosensitive layer (undercoat layer,
(intermediate layer, protective layer, etc.), for example, JP-A-51-10433.
If the polymer has a carboxyl group or a sulfo group as described in No. 8, a nil polymer can be contained.

The amount of the vinyl polymer used is preferably in the range of 0.05 to 2.0 in terms of dry weight ratio to the binder of the layer to which it is added.

The heat-developable photosensitive material of the present invention basically contains (1) photosensitive silver halide, (2) reducing agent, (3) dye-providing substance, and (4) in one heat-developable photosensitive layer. ) A binder is preferably contained, and (5) an organic silver salt is preferably contained as needed. However, these do not necessarily need to be contained in a single photographic constituent layer; for example, a heat-developable photosensitive layer with 2I
The components (1), (2), (4), and (5) above are contained in the heat-developable photosensitive layer on one side, and the dye-providing substance is contained in the layer on the other side adjacent to this photosensitive layer. (3) may be contained separately in two or more constituent layers as long as they are in a state where they can react with each other.

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

The heat-developable photosensitive material of the present invention has one or more heat-developable photosensitive layers on a support. In the case of color, it generally has three heat-developable photosensitive layers with different color sensitivities, and each photosensitive layer forms or releases dyes with different hues upon heat development.

Typically, 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 invention is not limited to this. 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 the support, or a structure in which a blue-sensitive layer is sequentially formed on the support. layer, a green-sensitive layer, a red-sensitive layer, or sequentially on a support,
There are configurations such as a green photosensitive layer, a red photosensitive layer, and a blue photosensitive layer.

In addition to the heat-developable photosensitive layer, the heat-developable photosensitive material of the present invention can be provided with non-photosensitive layers such as an undercoat layer, an intermediate layer, a protective layer, a filter layer, a backing layer, and a release layer. In order to coat the heat-developable photosensitive layer and these non-photosensitive layers on the support, a general silver halide photosensitive material is coated.
A method similar to that used to make A can be applied.

Namely, dip method, roller method, reverse roll method, air knife method, doctor blade method, spray method,
There are methods and devices for the bead method, extrusion method, stretch flow method, curtain method, etc.

The heat-developable photosensitive material of the present invention is subjected to imagewise exposure, usually at 80°C to 20°C.
1 at a temperature range of 0°C, preferably 100°C to 110°C.
Developing can be carried out by simply heating the film for 1.5 seconds to 180° C., preferably for 1.5 seconds to 120 seconds. The transfer of the diffusible dye to the a-receiving layer may be performed 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;
The image may be transferred by bringing the pattern into close contact with an image receiving member on a heat-developable pattern and heating it, or by bringing it into close contact with an image receiving member after supplying water and further heating if necessary. Also, before exposure, 70℃~180℃
Preheating may be performed within the temperature range of . Also, JP-A-60
As described in No. 143338 and Patent Application No. 60-3644, the photosensitive material and the image receiving member are preheated at a temperature of 80°C to 250°C immediately before thermal development transfer to improve mutual adhesion. Good too.

Various exposure means can be used for the photothermographic material according to the present invention. The latent image is obtained by imagewise exposure to radiation, including visible light. - Light sources generally used for conventional color printing, such as tungsten lamps, mercury lamps, xenon lamps, laser beams, CRT beams, etc., can be used as the light source.

As the heating means, all methods applicable 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. There are no particular restrictions on the heating pattern, including methods of preheating (preheating) and then reheating, heating at a high temperature for a short time, or at a low temperature for a long time, continuously increasing, decreasing, or repeating, and even discontinuously. Although heating is possible,
A simple pattern is preferred. Alternatively, a method in which exposure and heating proceed simultaneously may be used.

The image-receiving layer of the image-receiving member that can be effectively used in the present invention includes:
It is sufficient that it has the function of receiving the dye in the heat-developable photosensitive layer released or formed by heat development, for example, a polymer contained in a tertiary amine or a quaternary ammonium salt, as described in US Pat.
．． Those described in No. 709.690 are preferably used. For example, as a polymer containing an ammonium salt, the ratio of polystyrene-N,N,N-tri-0-hexyl-N-vinyl-benzylammonium chloride is 1:4 to 4:1, preferably 1:1. be.

Examples of polymers containing tertiary amines include polyvinylpyridine. A typical image-receiving layer for diffusion transfer is 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 JP-A-57-2072.
The glass transition temperature described in No. 50 etc. is 40°C or higher, 2
Examples include those formed of organic polymeric substances that are heat resistant to 50° C. or lower.

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

Examples of the heat-resistant organic polymer substances include polystyrene, polystyrene derivatives having substituents having 4 or less carbon atoms, polyvinylcyclohexane, polydivinylbenzene,
Polyvinylpyrrolidone, polyvinylcarbazolevinylalcohol, polyvinylform. Polyacetals such as marl and polyvinyl butyral, polyvinyl chloride, chlorinated polyethylene, polytrichloride fluoroethylene, polyacrylonitrile, polyN. N-dimethylallylamide, polyacrylate with p-cyanophenyl group, pentachlorophenyl group and 2,4-dichlorophenyl group, polyacrylchloroacrylate, polymethylmethacrylate, bolier. Chil methacrylate, polypropyl methacrylate, polyisopropyl methacrylate, polyisobutyl methacrylate, polyter
t-butyl methacrylate, polycyclohexyl methacrylate, polyethylene glycol dimethacrylate,
Examples include polyesters such as poly-2-cyano-ethyl methacrylate and polyethylene terephthalate, polycarbonates such as polysulfone and bisphenol A polycarbonate, polyanhydrides, polyamides, and cellulose acetates. In addition, Polymer Handbook Second Edition (edited by J. Brandrup and E.H. Inmargat), John Willy & Sons (ponyIller Hand)
book 2nd ed, (J, Brandr
up, E.

Edited by H. Immergut) John Wiley &amp;
5ons) Glass transition temperature listed in the publication 40
Synthetic polymers below 0 C are also useful. -Numerically, the molecular weight of the polymer substance is 2,000 to 200,000.
is useful. 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.

Useful polymers include cellulose acetates such as triacetate and diacetate, polyamides in combinations such as heptamethylene diamine and terephthalic acid, fluorene propylamine and adipic acid, hexamethylene diamine and diphenic acid, hexamethylene diamine and isophthalic acid, and diethylene glycol. and diphenylcarboxylic acid, bis-p-carboxyphenoxybutane and ethylene glycol, polyester, polyethylene terephthalate, and polycarbonate. These polymers may be modified. For example, polyethylene terephthalate using cyclohexane dimetatool, isophthalic acid, methoxypolyethylene glycol, 1,2-dicarbomethoxy4-benzenesulfonic acid, etc. as a modifier is also effective.

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

These polymers can also be used as a support and receiver ti11 (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, transparent supports, opaque supports, etc. may be used, but for example, films such as polyethylene terephthalate, polycarbonate, polystyrene, polyvinyl chloride, polyethylene, polypropylene, etc., and these supports may be used. supports containing pigments such as titanium oxide, barium sulfate, calcium carbonate, and talc, baryta paper, RC paper laminated with thermoplastic resin containing pigments, cloth, glass, aluminum, etc. Metals, etc., supports on which an electron beam curable resin composition containing a pigment is coated and cured, and supports on which a coating layer containing a pigment is provided. etc.

In particular, a support that is coated with an electron beam curable resin composition containing a pigment on paper and cured, or a support that has a pigment coating layer directly on the paper or an electron beam curable resin composition on the pigment coating layer. The support coated with the composition and cured can be used as an image-receiving member as it is because the resin layer itself can be used as an image-receiving layer.

When the present invention is applied to a heat-developable color light-sensitive material, the various polymers mentioned above can be used as a mordant for a dye image and as an image-receiving layer. It may be an image-receiving element or the image-receiving layer may be a single layer that is part of a heat-developable color photographic material. If necessary, an opacifying layer (reflection layer) may be included in the light-sensitive material, such layer reflecting the desired degree of radiation, such as visible light, which can be used to observe the dye image in the image-receiving layer. It is used to make The opacifying layer (reflective layer) can contain various reagents that provide the necessary reflection, such as titanium dioxide.

The image-receiving layer of the image-receiving member can also be formed into a type that can be peeled off from the heat-developable photosensitive layer. For example, after imagewise exposure of a heat-developable color light-sensitive material, a receiving layer may be superimposed on the heat-developable light-sensitive layer and uniformly heat-developed. Further, after imagewise exposure and uniform heat development of the heat-developable color light-sensitive material, an image-receiving layer may be superimposed and heated at a temperature lower than the development temperature to transfer the dye image released or formed from the dye-providing substance.

It is preferable to provide a retainer in the heat-developable photosensitive material of the present invention. Hereinafter, this will be referred to as the protective layer of the present invention.

Various additives used in the photographic field can be used in the protective layer of the present invention. These additives include various matting agents, colloidal silica, slip agents, organic fluoro compounds (especially fluorosurfactants), antistatic agents, ultraviolet absorbers, high-boiling organic solvents, antioxidants, hydroquinone derivatives, and polymers. Examples include latex, surfactants (including polymeric surfactants), hardeners (including polymeric hardeners), organic silver salt particles, non-photosensitive silver halide particles, and the like.

The matting agent used in the protective layer of the present invention is fine particles of inorganic or organic substances that are incorporated into the photothermographic material to increase the roughness of the surface of the photosensitive material and make it matte. be.

A matting agent is used to prevent adhesion that occurs during production, storage, use, etc. of photosensitive materials, and to prevent contact between substances of the same or different types, II! Methods for preventing charging caused by rubbing and peeling are well known in the art. Specific examples of matting agents include silicon dioxide described in JP-A-50-46316, JP-A-53-7231, and JP-A-58-66937.
No. 60-8894, an alkali-soluble matting agent such as an alkyl methacrylate/methacrylic acid copolymer,
Alkali-soluble polymer having an anionic group described in JP-A-58-166341, JP-A-58-145935
A combination of two or more types of fine particle powders with different Mohs hardnesses, a combination of oil droplets and fine particle powders as described in JP-A-58-147734, two types with different average particle sizes as described in JP-A-59-149356 Combination of the above spherical matting agents, JP-A-56
A combination of a fluorinated surfactant and a matting agent described in No. 44411, British Patent No. 1,055.713, U.S. Patent No. 1,939,213, U.S. Patent No. 2,221,873,
2.268.662, 2,322,037, 2,376,005, 2,391,181, 2,701,245, 2.992,101,
3.079.257, 3.262.782,
3,443,946, 3,516,832, 3.539.344, 3.591, 379
No. 3.754.924, No. 3.16γ, No. 448, Jikai TJ! No. 149-106821, No. 57-148
Written in issue 35 etc. I! Organic matting agent, West German patent 2
, 529.321, British Patent No. 760.775, British Patent No. 1,260,772, U.S. Patent No. 1,201,905
No. 2,192,241, No. 3.053.662, No. 3,062,649, No. 3,257,206
No. 3,322,555, No. 3,353.958, No. 3,370,951, No. 3,411,907,
3,437,484, 3.523.022, 3,615,554, 3.635.714,
3.769,020, 4,021,245,
Inorganic matting agents described in JP-A No. 4.029.504, etc., or JP-A-46-7781 and JP-A-49-49-
No. 106821, No. 51-6017, No. 53-1
No. 16143, No. 53-100226, No. 57-1
No. 4835, No. 57-82832, No. 53-7042
No. 6, No. 59-149357, Special Publication No. 57-905
Matting agents having physical properties such as those described in Publication No. 3 and EP-107,378 are preferably used.

In the protective layer of the present invention, the amount of the matting agent added is 1011 J/2. Og is preferred, more preferably 20a1g to 1. It is Og. The particle size of the matting agent is 0.5
~10μm is preferable, more preferably 1.0~6μm
It is.

The matting agents may be used in combination of two or more.

Examples of the slippery agent used in the protective layer of the present invention include solid paraffin, oils and fats, surfactants, natural waxes, synthetic waxes, etc. Specifically, French Patent No. 2.1
80.465, British Patent No. 955,061, 1.
143.118, 1,270,578, 1,3
No. 20.564, No. 1,320,757, Japanese Unexamined Patent Publication No. 1973
-5017, 51-141623, 54-15
No. 9221, No. 56-81841, Research Disclosure
) 13969, U.S. Patent No. 1,263,722
No. 2.588.765, No. 2.739.891, No. 3,018.178, No. 3,042,522, No. 3,080,317, No. 3,082.087, No. 3,121,060, No. 3,222,178
No. 3.295.979, No. 3.489.567, No. 3,516,832, No. 3,658,573,
Those described in No. 3,679,411, No. 3,870.521, etc. can be preferably used.

The protective layer of the present invention contains a high boiling point organic solvent (for example, U.S. Pat. No. 2,322,027, U.S. Pat.
No. 533,514, No. 2,882,157, Special Publication No. 4
No. 6-23233, British Patent No. 958.441, No. 1
, 222.753, U.S. Patent No. 2.353.262
No. 3.676, No. 142, No. 3.700.454, JP-A No. 50-82078, No. 51-27921,
Esters (e.g., phthalate esters, phosphoric acid esters, fatty acid esters, etc.), amides (e.g., fatty acid amide, sulfonic acid amide, etc.), ethers, alcohols, paraffins, etc., described in No. 51-141623, etc. Examples include. ) may contain oil droplets in which a water-insoluble oil compound is emulsified and dispersed. Furthermore, these oil droplets may contain photographic additives for various purposes.

Binders used in the protective layer of the present invention include polyvinyl butyral, polyvinyl acetate, ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinyl pyrrolidone, polyethyl oxazoline, polyacrylamide,
One or a combination of two or more synthetic or natural polymeric substances such as gelatin and phthalated gelatin can be used.

In particular, gelatin (including gelatin derivatives), polyvinyl and lolidon (molecular weight preferably 1,000-400,000), polyvinyl alcohol (molecular weight 1,000-400,000),
100,000) and polyoxazoline (molecular weight preferably 1,000 to 800,000) alone or in combination of two or more of these binders are preferred, and gelatin alone or gelatin and the above-mentioned polyvinylpyrrolidone, polyvinyl alcohol, and polyoxazoline are preferred. Particularly preferred are binders that use hydrophilic polymers that are highly compatible with gelatin, such as the following. Gelatin may be treated with lime, acid, or ion exchange, and may be ossein gelatin, big skin gelatin, hydrogelatin, or modified gelatin obtained by esterifying or phenylcarbamoylating these gelatins.

The thickness of the protective layer of the present invention is preferably from O,OS to 5 μm, more preferably from 0.1 to 1.0 μm. The protective layer may be a single layer or may be composed of two or more layers.

Further, in order to increase film strength and prevent film destruction, it is also preferable that the degree of hardness of the protective layer is greater than that of the photosensitive layer. One way to make the hardness of the protective layer higher than that of the photosensitive layer, that is, to control the hardness of each layer, is to use a diffusion-resistant hardener. By using it in the protective layer, only the degree of hardness of the protective layer can be made greater than that of the photosensitive layer. Polymer hardeners are known as diffusion-resistant hardeners, such as those disclosed in U.S. Pat. Nos. 3,057.723 and 3.396
．． No. 029, No. 4,161,407, JP-A-58-5
Hardeners described in No. 0528 and the like can be used.

Another way to control the degree of dura for each layer is to
Protection can be achieved by containing a diffusible hardener (for example, a vinyl sulfone hardener) only in the protective layer, or by making the content of the protective layer higher than that of the photosensitive layer, and quickly drying it after simultaneous multilayer coating. The hardness of the layer can be greater than that of the photosensitive layer.

[Effects of the Invention] The present invention provides a heat-developable photosensitive material having at least a photosensitive silver halide, a dye-providing substance, a reducing agent, an acidic component, and a binder on a support, which temporarily blocks the involvement of acidic components. By providing a layer, a stable image can be obtained even if the heat development processing conditions change, and there is no drawback such as increased fog or a decrease in image density during long-term storage, and the stability of the heat development process is improved. It has excellent long-term storage stability.

[Examples] Hereinafter, specific examples of the present invention will be described in detail, but the present invention is not limited to these embodiments.

Example-1 [Preparation of silver iodobromide emulsion] At 50°C, JP-A No. 57-92523, No. 57-
An aqueous solution 500 containing 11.60 g of potassium iodide and 131 g of potassium bromide in solution (A) in which 209 ossein gelatin, 1000 i12 of distilled water, and ammonia were dissolved using the mixer shown in No. 92524. Dai's <8) solution and 500 μm of solution (C), an aqueous solution containing 1 mol of silver nitrate and ammonia, were simultaneously added while keeping DAtl constant. The shape and size of the emulsion grains to be prepared are l
) H, I) Adjusted by controlling the addition rate of A9 and solution and C solution. In this way, silver iodide content of 7 mol%
A core emulsion having a regular octahedral shape and an average grain size of 0.25 μm was prepared.

Next, by coating a silver halide shell with a silver iodide content of 1 mol % in the same manner as above, a core/shell type silver halide emulsion with a regular octahedron and an average grain size of 0.3 μm was obtained. 1i was made. The monodispersity was 9%. ) The emulsion thus prepared was washed with water and desalted.

Emulsion yield was 800i12.

[Preparation of organic silver salt dispersion] 5-methylbenzotriazole 8128. obtained by reacting 5-methylbenzotriazole and 5f4 acid silver in a water-alcohol mixed solvent. ag, poly(N-vinylpyrrolidone) is, og, and 4-sulfobenzotriazole sodium salt 1.33i7 were dispersed in an alumina ball mill to obtain pi-15,5 and 2001β.

[Preparation of dye-providing substance dispersion] Exemplary dye-providing substance @30. Og to tricresyl phosphate 3
00g and ethyl acetate 90. (Gelatin aqueous solution 46011 dissolved in hR and containing the following fluorosurfactant)
2 and dispersed with an ultrasonic homogenizer, ethyl acetate was distilled off, and water was added to obtain 500112.

Surfactant (m, n = 2 or 3) [Preparation of photosensitive silver halide dispersion] The silver halide emulsion prepared above was mixed with the following sensitizing dye (1).
and 4-hydroxy-6-medyru 1゜3.3a,
A photosensitive silver halide dispersion having the following composition was prepared by sulfur sensitization treatment with sodium thiosulfate in the presence of 7-tetrazaindene.

Silver halide (in terms of silver) 381 g Gelatin 85 g/28201Q or less Margin sensitizing dye (1) [Preparation of dispersion of acid precursor Co-acid precursor (AP-2) 25 (l) was mixed with 100 g of gelatin aqueous solution and dispersed in an alumina ball mill.

[Preparation of heat-developable photosensitive material 1 The silver halide dispersion 40.0d, the gravel silver salt dispersion 25. Chf;l, the dye-donor dispersion liquid 100.
(hf was combined, and as a hot solvent, 4.2 g of polyethylene glycol 300 (manufactured by Kanto Kagaku Co., Ltd.) and 10% by weight of 1-phenyl-4,4-dimethyl-3-pyrazolidone were added.
7.5d of methanol and tetra(vinylsulfonylmethyl) methanetrifluoride were reacted in a ratio of 1:1 (12 ratio), and the phenylcarbamoylated geladine was dissolved in a 1% water-alcohol solution. ) A hardener solution containing 3% methane (3.0% by weight) and a 10% water-alcoholic solution of guanidine trichloroacetic acid (4% by weight)
0.0 ml was added and coated on a photographic polyethylene terephthalate film with a thickness of 180 μl that had been undercoated so that the amount of silver was 2.5 Q/f.

[Preparation of heat-developable photosensitive material-B except that 10 iN of the acid precursor dispersion was added.
In the same manner as heat-developable photosensitive material-A, heat-developable photosensitive material-B was prepared.
It was created.

[Preparation of heat-developable photosensitive material-C] 10.0 g of a 10% gelatin aqueous solution, 13.01 g of water, 2.4 iN of the acid precursor dispersion and 1.2 d of the hardener solution were added, and subbing was performed. The film was coated onto a photographic film having a thickness of 180 μm to a wet film thickness of 50 μm. Next, 10.0 d of 10% gelatin aqueous solution,
Poly(N-vinylpyrrolidone) 10% aqueous solution 5.0iL
2, water 8 vt2 and the hardener solution 1.8. Q was added to give a wet film thickness of 35 μm.

Furthermore, a photosensitive layer was coated on this film in the same manner as in the above-mentioned heat-developable photosensitive material-8.

[Preparation of Image Receiving Member] The following layers were sequentially coated on a transparent polyethylene terephthalate film having a thickness of 100 μm.

(1) Styrene and N-benzyl-N, N-dimethyl-N
- A layer consisting of a 1=1 copolymer of (3-maleimidopropyl) ammonium chloride and gelatin (copolymer 3.0 g/f, gelatin 3.0 (1/f)) (2) Urea, N-methylurea and E (urea 2.0 (1/f) consisting of polyvinyl alcohol (saponification degree 98%)
, N-methylurea 2.0g/f, polyvinyl alcohol 3. OQ/f) Next, the sample of the photothermographic material prepared above was subjected to the following treatment.

That is, for each sample, 2
Storage for days (condition-1), temperature 25℃ and relative humidity 60% 2
The sample was stored for a month (condition-2, left to naturally stand).

For each sample, pass 1600 min through a step wedge.
It was exposed to C, M, and S light, and was then thermally developed together with the image receiving member at 150° C. for 1 minute.

The samples subjected to the above condition-1 were thermally developed together with the image receiving member at 150° C. for 1 minute or 1 minute and 30 seconds. Thereafter, the image receiving member and the photosensitive material were quickly peeled off.

The transmission density of the yellow transparent image obtained on the surface of the image receiving member was measured using a densitometer (PDA-65, manufactured by Konishiroku Photo Industry Co., Ltd.) in terms of maximum density and minimum density.

The results are shown in Table 1 below.

As is clear from the results in Table 1, comparative samples (A, B
), sample C of the present invention exhibits a small increase in both the maximum and minimum concentrations even when the heating time is changed, and has excellent long-term storage stability, which is an improvement.

Example-2 Example-2 except that the acid precursor shown in Table-2 was used instead of the acid precursor of photosensitive material B of Example-1.
Samples B-1 to B-5 were prepared in exactly the same manner as in Example 1 and subjected to heat development. Sample C was prepared using the acid precursor shown in Table 2 for photosensitive material C in a roughly similar manner.
-1 to G-5 were prepared and thermally developed, and the results shown in Table-2 were as shown in Table-2. In contrast, the present invention (7
) It can be seen that the M materials (C-1 to c-5) showed little increase in both the maximum and minimum concentrations even when the heating time was changed, and the long-term storage stability was excellent and improved.

Example-3 Dye-providing substance used in photosensitive materials B and C of Example-1 @3
In place of the dispersion of No. 09, dye-providing substances ■ and ■ No. 20
Samples B-6, 8-7, 0-6, 0-7 were prepared in exactly the same manner as B and C except that the dispersion liquid dispersed in g was used.
was prepared and subjected to the same heat development treatment as in Example-1.

As is clear from Table 3, even if the dye-donating substance used is changed, the samples of the present invention (C-6, 0-7) differ from the comparative samples (B-6, 8-7) even if the heating time is changed. Also, there is little increase in both the maximum and minimum concentrations, and it has excellent long-term storage stability.
You can see that it has been improved.

Example-4 [Preparation of heat-developable photosensitive material] Photosensitive silver halide dispersion prepared in Example-1 45.
OtN, 25.01 g of Ariden silver salt dispersion, and 110.0 d of dye-providing substance dispersion were mixed, and as a heat solvent, 3.5 g of polyethylene glycol 300 (manufactured by Kanto Kagaku Co., Ltd.) was added.
72 g of a 10% by weight methanol solution of 1-phenyl-4,4-dimethyl-3-pyrazolidone, 121 g of the acid precursor dispersion prepared in Example 1, and 1:1 of tetra(vinylsulfonylmethyl)methane and taurine. (weight ratio), phenylcarbamoylated gelatin 1
Hardener solution containing 3% by weight of tetra(vinylsulfonylmethyl)methane dissolved in a % water-alcohol solution3.
0, and 1 Ofnffi of guanidine trichloroacetic acid.
% water-alcohol solution was added thereto and coated onto a subbed photographic polyethylene terephthalate film having a thickness of 180 μm so as to give silver fh 2.6 (1/v2).

[Preparation of heat-developable photosensitive material-E] 10.0 d of 10% aqueous piratin solution, 13.0 d of water. o, (1,
2.41 g of acid precursor dispersion prepared in Example-1
and the hardener solution 1.2. Q and 50LtIll on a 180μm thick undercoated photographic film.
It was applied to a wet film thickness of .

Next, 8.0d of 10% gelatin aqueous solution, 4.0d of 10% poly(N-vinyl and lolidon) aqueous solution. o1β, water 1°1β, and the following solid hot solvent HS-1. og and 1.5 μm of the above hardener solution were added to give a wet film thickness of 35 μm. Furthermore, a photosensitive layer was coated on this film in the same manner as the photothermographic material-D.

H3-1 (Solid thermal solvent) The solid thermal solvent is 1% of poly(N-vinylpyrrolidone)
An aqueous solution was used as a dispersion medium, and an alumina ball mill dispersed solution was added.

[Preparation of heat-developable photosensitive material] Completely the same method as for photothermographic material-E, except that the following solid heat solvent HS-2 was used instead of the solid heat solvent HS-1 of the heat-developable photosensitive material-E. Thus, photosensitive material-F was prepared. These samples were thermally developed in the same manner as in Example 1, and the results shown in Table 4 were obtained.

1-13-2 (Solid thermal solvent) As is clear from the results in Table 4, the samples (E, F) of the present invention had a shorter heating time than the comparative sample (D). It can be seen that even when the concentration is changed, there is little increase in both the maximum concentration and the minimum concentration, and the long-term storage stability is excellent and improved.

Patent applicant: Konishiroku Photo Industry Co., Ltd. Representative Patent Attorney Miyao Ichinose Procedural amendment (voluntary) March 3Q, 1985

Claims (3)

[Claims] (1) A heat-developable photosensitive material having at least a photosensitive silver halide, a dye-donating substance, a reducing agent, an acidic component, and a binder on a support, which has at least one layer that temporarily shields the involvement of the acidic component. A heat-developable photosensitive material characterized by: (2) The photothermographic material according to claim 1, wherein the shielding layer contains a thermal solvent. (3) The heat-developable photosensitive material according to claim 1 or 2, wherein the shielding layer contains a substance that dissolves or swells with a hot solvent at a heat development temperature.