JP2655186B2 - Photothermographic material - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a photothermographic material, and more particularly to a photothermographic material which has excellent raw storability, high image density, and low image stain. It relates to a developed photosensitive material.

Furthermore, the present invention relates to a photothermographic material which can be manufactured with stable and constant performance.

(Background Art) Photothermographic materials using silver halide as a photosensitive component are known in the art, and are described, for example, in "Basics of Photographic Engineering", Non-Silver Salt Photography, ed. Page, published in April 1978, 40 pages of video information, Nebletts, Handbook of Photography and Repgraph
rography) 7th edition (7th Ed.) Juan Nostrand
Van Nostrand Reinhold
Company), pages 32 to 33; U.S. Patent No. 3,152,904;
No. 3,301,678, No. 3,392,020, No. 3,457,075, British Patent Nos. 1,131,108, 1,167,777, and Research Disclosure Magazine (hereinafter abbreviated as RD) June 1978
It is described on pages 9 to 15 of the monthly publication.

Many methods have been proposed for obtaining a color image (color image) by thermal development.

For example, US Pat. Nos. 3,531,286, 3,761,270 and 3,761,270 disclose a method of forming a color image by combining an oxidized form of a developing agent formed by reduction of silver halide with a coupler.
No. 4,021,240, Belgian Patent No. 802,519, RD-13742 and the like.

A method of forming a positive dye image by heat development by a silver dye bleaching method using silver halide is disclosed in U.S. Pat.
No. 7, RD-14433, RD-15227 and the like.

Further, a diffusible dye is formed or released imagewise from the dye-donating compound during the heat development of the silver halide, and the diffusible dye is transferred to a dye-fixing element having a mordant with a solvent such as water. A method of transferring to a dye-fixing element with a high-boiling organic solvent, a method of transferring to a dye-fixing element with a hydrophilic heat solvent incorporated in the dye-fixing element, the movable dye is heat-diffusible or sublimable, Methods of transferring to a dye receiving element such as a support have been proposed. In this method, a negative dye image or a positive dye image can be obtained with respect to the original by changing the type of the dye-donating compound used or the type of the silver halide emulsion (US Pat. 4,463,079, 4,474,867
Nos. 4,478,927, 4,507,380, 4,500,626,
No. 4,483,914, JP-A-58-149046, and 58-149047
Nos. 59-152440, 59-154445, 59-165054
Nos. 59-180548, 59-168439, 59-174832
Nos. 59-174833, 59-174834, 59-174835
No. 62-65038, No. 61-23245, European Patent Publication 210,
660A2 and 220,746A2).

(Problems to be Solved by the Invention) In the photothermographic material as described above, the built-in developer is a compound having the ability to reduce silver halide under high pH conditions during development processing. It is a compound that is mobile under conditions.

However, such a developer, in a solution state,
It has the disadvantage that it is easily oxidized by oxygen in the air. In particular, this oxidation reaction is more likely to occur as the pH of the solution increases.
h.Ed., by THJames, Macmillan, 1977). For this reason, when a developer having high solubility in water is used, when a photosensitive material is applied, when a coating aqueous solution containing the developer is aged for a long time or when the photosensitive material after production is stored under high humidity conditions, However, there is a problem that the developing agent is reduced by air oxidation, and as a result, silver development is delayed, and the discrimination of an image is deteriorated, or the air-oxidized developing agent becomes a coloring material, thereby producing an undesirable stain. I knew there was. Further, it has been found that when the developing agent is contained in the same coating layer as the basic metal compound, the above-mentioned oxidation reaction particularly occurs remarkably.

Also, when a developer having extremely low solubility in water is used, the development reaction in the exposed portion is delayed, and the image discrimination deteriorates. Regarding this point, Japanese Patent Application No. 63-204423 (JP-A-2-53049) discloses a 1-phenyl-3-pyrazolidinone derivative with respect to a positive color photosensitive material having a multilayer structure. From the above facts, it is considered that the solubility of the developer in water in the present light-sensitive material is a physical property value that greatly affects the performance of the light-sensitive material.

(Problems to be Solved by the Invention) An object of the present invention is to provide a photothermographic material having excellent raw preservability,
That is, an object of the present invention is to provide a photothermographic material capable of obtaining an image having a high image density and a low stain immediately after production and after storage over time.

It is a further object of the present invention to provide a photothermographic material which can be produced without deterioration of discrimination of the photosensitive material as a product with the lapse of time at the time of production, in particular, no increase in stain. .

(Means for Solving the Problems) In order to achieve the object of the present invention, the developer used in the present invention was examined in detail, and as a result, it was movable at the time of processing, and in a coating aqueous solution and with time after production. It has been found that such a developer having the stability of (1) has a solubility in water within a certain range.

That is, an object of the present invention is to provide a photothermographic method comprising at least two or more coating layers having at least a photosensitive silver halide, a binder, a developer and a basic metal compound which is hardly soluble in water on a support. In the material, as the developer,
Solubility in water at 25 ° C is 10 ^-7 mol or more per water 10 ^-3 m
ol or less of a developing agent is dispersed in a binder in fine particles and contained in a coating layer different from the basic metal compound.

As described above, the developing agent used in the present invention is a mobile compound having the ability to reduce silver halide under high pH conditions during processing.

Examples of such compounds include JP-A-59-177549.
Nos. 59-178458, 59-182449, 59-182450
And Japanese Patent Application No. 62-298571, which are known in the art as developing agents. Here, the compound examples are summarized as follows. And polyhydroxybenzene derivatives such as methylhydroxynaphthalene. Further, methyl gallate, ascorbic acid, ascorbic acid derivatives, hydroxylamines such as N, N'-di- (2-ethoxyethyl) hydroxylamine, 1-phenyl-3-pyrazolidone, 4-methyl-4-hydroxymethyl Pyrazolidones such as -1-phenyl-3-pyrazolidone, p-aminophenol, p-methylaminophenol, p-dimethylaminophenol, p-piperidinoaminophenol, 4-dimethylamino-2,6-dimethoxyphenol and the like Aminophenols, N-methyl-p
-Phenylenediamine, N, N, N ', N'-tetramethyl-
p-phenylenediamine, 4-diethylamino-2,6-
Phenylenediamines such as dimethoxyaniline, piperidinohexose reductone, reductones such as pyridinohexose reductone, hydroxytetronic acids and the like can be mentioned.In the present invention, among these derivatives, Solubility in water 1 at 25 ° C is 10 ^-7 mol or ^more1
Use those having 0 ^-3 mol or less.

Hereinafter, specific examples of the developing agent that can be used in the present invention are shown, but the developing agent used in the present invention is not limited to these.

The amount of the developing agent used has a wide range, but is preferably from 0.001 to 5 mol, preferably from 0.01 to 1.5 mol, per mol of silver halide. When a dye-donating compound is used, the total amount of the dye-donating compound is 0.
The amount is from 01 to 50 mol, more preferably from 0.1 to 5 mol.

Further, as the addition amount of the developer, any layer other than a coating layer of a basic metal compound that is hardly soluble in water may be used, and any of a photosensitive layer, a protective layer, and an intermediate layer can be selected.
It is possible to add them all at once, or to add them separately in two or more layers.

In the present invention, the fine particles when defining the fine particle dispersion has an average particle size of 0.01 to 50 μm, preferably 0.05 to 50 μm.
It means particles of the developer itself in the range of 5 μm.
The particle size distribution is not particularly limited.

By doing so, the developer in the present invention is locally present in the binder.

Examples of a method for preparing the dispersion include a method using a mill described in Japanese Patent Application No. 56-174830.
At that time, the average particle size is preferably 10 microns or less, particularly preferably 5 microns or less.

Further, when the developer is dispersed in a hydrophilic colloid,
Various surfactants can be used.

For example, those described as surfactants on pages (37) to (38) of JP-A-59-157636 can be used.

The hardly soluble basic metal chloride used in the present invention is 25 ° C.
Is a basic metal salt having a solubility in water (the number of grams of a substance dissolved in 100 g of water at 25 ° C.) of 0.5 or less. Such metal salts include carbonates, phosphates, silicates, borates, aluminates, hydroxides, oxides, and double salts of these compounds.

The basic metal salt compounds include a base generator used in an image forming reaction known in JP-A-62-129848, U.S. Pat. No. 4,740,445 and the like, and an image discriminator described in JP-A-61-20943. It is used as a pigment or the like for improving essence.

 Hereinafter, specific examples of the basic metal salt compound will be described.

Calcium carbonate, barium carbonate, magnesium carbonate,
Zinc carbonate, strontium carbonate, magnesium calcium carbonate (CaMg (CO ₃ ) ₂ ), magnesium oxide, zinc oxide, tin oxide, cobalt oxide, zinc hydroxide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, antimony hydroxide, Tin hydroxide, iron hydroxide, bismuth hydroxide, manganese hydroxide, calcium phosphate, magnesium phosphate, magnesium borate, calcium silicate, magnesium silicate, zinc aluminate, calcium aluminate, basic zinc carbonate (2ZnCO _{3 3Zn (OH) 2 · H 2} O), basic magnesium carbonate _{(3MgCO 3 · Mg (OH)} 2 · 3H 2 O),
Basic nickel carbonate (NiCO ₃ · 2Ni (OH) ₂ ), basic bismuth carbonate (Bi ₂ (CO ₃ ) O ₂ · H ₂ O), basic cobalt carbonate (2CoCO ₃ · 3Co (OH) ₂ ), oxidation Aluminum Magnesium The amount of the basic metal salt compound that is hardly soluble in water has a wide range, but is preferably 50 wt% or less, more preferably 0.01 to 40 wt%, in terms of the weight of the coating film.

Basic metal compounds that are hardly soluble in water are described in JP-A-56-174830.
It is desirable to incorporate it as a fine particle dispersion prepared by the method described in JP-A-53-102733 and the like, and the average particle size is preferably 50 μm or less, particularly preferably 5 μm or less.
The metal compound may be any layer other than the coating layer of the developer,
It may be added to any layer of the photosensitive material such as a photosensitive layer, an intermediate layer and a protective layer, or may be added in two or more layers.

The photothermographic material of the present invention basically has a photosensitive silver halide, a binder and a basic metal compound which is hardly soluble in water with the above-mentioned developer and water on a support. An organic metal salt oxidizing agent, a dye-donating compound (which may also serve as a reducing agent as described later), and the like can be contained. Except for the basic metal compound which is hardly soluble in the developer and water, these components are often added to the same layer, but they can also be added in separate layers if they can react. . For example, if a coloring dye-providing compound is present in the lower layer of the silver halide emulsion, the sensitivity can be prevented from lowering. The reducing agent is preferably incorporated in the photothermographic material, but may be supplied from the outside by, for example, a method of diffusing from a dye fixing material described later.

In order to obtain a wide range of colors in the chromaticity diagram using the three primary colors of yellow, magenta and cyan, at least three silver halide emulsion layers sensitive to different spectral regions are used in combination. For example, blue layer, green layer,
There are a combination of three red-sensitive layers, a combination of green-sensitive layers, red-sensitive layers, and infrared-sensitive layers. Each photosensitive layer can adopt various arrangement orders known for ordinary type color photosensitive materials. Each of these photosensitive layers may be divided into two or more layers as necessary.

The photothermographic material can be provided with various auxiliary layers such as a protective layer, an undercoat layer, an intermediate layer, a yellow filter layer, an antihalation layer, and a back layer.

The silver halide that can be used in the present invention may be any of silver chloride, silver bromide, silver iodobromide, silver chlorobromide, silver chloroiodide, and silver chloroiodobromide.

The silver halide emulsion used in the present invention may be a surface latent image type emulsion or an internal latent image type emulsion. The internal latent image type emulsion is used as a direct reversal emulsion in combination with a nucleating agent or light fogging. A so-called core-shell emulsion in which the inside of the grain and the surface layer of the grain have different phases may be used. The silver halide emulsion may be monodispersed or polydispersed, or a mixture of monodispersed emulsions may be used. Particle size is 0.1 ~
2μ, especially 0.2-1.5μ, is preferred. The crystal habit of the silver halide grains may be any of cubic, octahedral, tetrahedral, high aspect ratio tabular, and the like.

Specifically, U.S. Patent No.
Any of the silver halide emulsions described in No. 28,021, Research Disclosure Magazine (hereinafter abbreviated as RD) 17029 (1978), and JP-A No. 62-253159 can be used.

The silver halide emulsion may be used as it is after unripe, but usually it is used after chemical sensitization. A known sulfur sensitization method, reduction sensitization method, noble metal sensitization method, or the like can be used alone or in combination for an emulsion for a normal photosensitive material. These chemical sensitizations can also be carried out in the presence of a nitrogen-containing heterocyclic compound (JP-A-62-253159).

The coating amount of the photosensitive silver halide used in the present invention is in the range of 1 mg to 10 g / m ² in terms of silver.

In the present invention, an organic metal salt can be used as an oxidizing agent together with the photosensitive silver halide. Among such organic metal salts, an organic silver salt is particularly preferably used.

Organic compounds that can be used to form the above-mentioned organic silver salt oxidizing agent include benzotriazoles, fatty acids and other compounds described in U.S. Pat. No. 4,500,626, columns 52-53. Also useful are silver salts of carboxylic acids having an alkynyl group such as silver phenylpropiolate described in JP-A-60-113235 and acetylene silver described in JP-A-61-249044. Two or more organic silver salts may be used in combination.

The above organic silver salts can be used in an amount of 0.01 to 10 mol, preferably 0.01 to 1 mol, per 1 mol of the photosensitive silver halide. The total coating amount of the photosensitive silver halide and the organic silver salt is suitably from 50 mg to 10 g / m ² in terms of silver.

In the present invention, various antifoggants or photographic stabilizers can be used. An example is RD17643
(1978) Azoles and azaindenes described on pages 24 to 25, carboxylic acids and phosphoric acids containing nitrogen described in JP-A-59-168442, or mercapto compounds and metals thereof described in JP-A-59-111636 Salts and acetylene compounds described in JP-A-62-87957 are used.

The silver halide used in the present invention may be spectrally sensitized with methine dyes or the like. Dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes.

Specifically, U.S. Pat.No. 4,617,257, JP-A-59-180
No. 550, No. 60-140335, RD17029 (1978), pp. 12-13, and the like.

These sensitizing dyes may be used alone, or a combination thereof may be used.
Often used for supersensitization.

Along with the sensitizing dye, a dye which does not itself have a spectral sensitizing effect or a compound which does not substantially absorb visible light and exhibits supersensitization may be contained in the emulsion (for example, US Pat. No. 3,615,641). And those described in JP-A-63-23145).

These sensitizing dyes may be added to the emulsion at or before or after chemical ripening, or may be added to U.S. Pat.
No. 4,225,666 before and after the nucleation of silver halide grains. The addition amount is generally about 10 ^-8 to 10 ^-2 mol per mol of silver halide.

As the binder for the constituent layers of the photosensitive material and the dye fixing material, hydrophilic binders are preferably used. Examples thereof include those described on pages (26) to (28) of JP-A-62-253159. Specifically, transparent or translucent hydrophilic binders are preferred, for example, gelatin, proteins or cellulose derivatives such as gelatin derivatives, starch, gum arabic, dextran, natural compounds such as polysaccharides such as pullulan, polyvinyl alcohol, Examples include polyvinylpyrrolidone, acrylamide polymers, and other synthetic polymer compounds. Furthermore, superabsorbent polymers described in JP-A-62-245260, i.e. -COOM or -SO ₃ M (M
Is a homopolymer of a vinyl monomer having a hydrogen atom or an alkali metal) or a copolymer of the vinyl monomers or other vinyl monomers (for example, sodium methacrylate, ammonium methacrylate, Sumikagel L-manufactured by Sumitomo Chemical Co., Ltd.) 5H) is also used. These binders can be used in combination of two or more kinds.

When a system for performing thermal development by supplying a small amount of water is used, it is possible to quickly absorb water by using the above superabsorbent polymer. When the superabsorbent polymer is used for the dye-fixing layer and its protective layer, it is possible to prevent the dye from being re-transferred from the dye-fixing material to another after transfer.

In the present invention, the coating amount of the binder is 1 m ² per 20g
The following is preferable, and particularly, it is suitably 10 g or less, more preferably 7 g or less.

Various polymers are included in the constituent layers (including the back layer) of the photosensitive material or the dye fixing material for the purpose of improving film physical properties such as dimensional stabilization, curling prevention, adhesion prevention, film crack prevention, and pressure sensation. Latex can be included. Specifically, JP-A Nos. 62-245258, 62-136648, 62
Any of the polymer latexes described in JP-110066 or the like can be used. In particular, when a polymer latex having a low glass transition point (40 ° C. or less) is used for the mordant layer, cracking of the mordant layer can be prevented, and when a polymer latex having a high glass transition point is used for the back layer, the curl prevention effect is reduced. can get.

In the present invention, a diffusion-resistant reducing agent can be used together with the developer. As the diffusion-resistant reducing agent, those known in the field of photothermographic materials can be used. Further, a dye-providing compound having a reducing property described later is also included (in this case, another reducing agent may be used in combination). Further, a reducing agent precursor which does not itself have a reducing property but expresses a reducing property by the action of a nucleophilic reagent or heat during the development process can be used.

The diffusion-resistant reducing agent may be any one that does not substantially move in the layer of the light-sensitive material, and is preferably a hydroquinone, a sulfonamidophenol, or a sulfonamidonaphthol having a bulky group called a ballast group. Kind,
Examples thereof include compounds described as electron donors in JP-A-53-110827, and dye-donating compounds having diffusion resistance and reducing property described later. In the present invention, the addition amount of the diffusion-resistant reducing agent is 0.001 to 20 mol per mol of silver,
Particularly preferably, it is 0.01 to 10 mol.

In the present invention, silver can be used as the image forming substance. In addition, when silver ions are reduced to silver under high temperature conditions, they may contain a compound that generates or releases a mobile dye corresponding to this reaction or vice versa, that is, contains a dye-donating compound. it can.

First, examples of the dye-donating compound that can be used in the present invention include a compound (coupler) that forms a dye by an oxidative coupling reaction. The coupler may be a 4-equivalent coupler or a 2-equivalent coupler. Also,
A 2-equivalent coupler having a nondiffusible group as a leaving group and forming a diffusible dye by an oxidative coupling reaction is also preferable. The diffusion resistant group may form a polymer chain. Specific examples of color developers and couplers are described in James, The Theory of the Photographic Process, 4th Edition.
Edition (TH James “The Theory of the Photographic Pro
cess "), pages 291-334, and 354-361, JP-A-58-123.
No. 533, No. 58-149046, No. 58-149047, No. 59-11114
No. 8, No. 59-124399, No. 59-174835, No. 59-231539
No. 59-231540, No. 60-2950, No. 60-2951, No.
Nos. 60-14242, 60-23474, and 60-66249.

Further, as another example of the dye-donating compound, a compound having a function of releasing or diffusing a diffusible dye imagewise can be mentioned. This type of compound can be represented by the following general formula [LI].

(Dye-Y) nZ [LI] Dye represents a dye group, a temporarily shortened dye group or a dye precursor group, Y represents a simple bond or linking group, and Z represents an image-like latent image. (Dye-Y) n-Z to cause a difference in the diffusivity of the compound represented by (Dye-Y) nZ, or to release Dye and to release the released Dye and (Dye- Y) represents a group having a property that causes a difference in diffusivity with n-Z, n represents 1 or 2, and when n is 2, two Dye-Ys are the same but different. Is also good.

Specific examples of the dye donating compound represented by the general formula [LI] include the following compounds.
The following items (1) to (2) form a diffusible dye image (positive dye image) in reverse correspondence to the development of silver halide.
Is to form a diffusible dye image (negative dye image) corresponding to the development of silver halide.

U.S. Pat.Nos. 3,134,764, 3,362,819, 3,591
No. 7,200, No. 3,544,545, No. 3,482,972, etc., a dye developer comprising a hydroquinone-based developer and a dye component linked thereto. This dye developer is diffusible in an alkaline environment, but becomes non-diffusible when reacted with silver halide.

As described in U.S. Pat. No. 4,503,137, non-diffusible compounds which release a diffusible dye in an alkaline environment but lose their ability when reacted with silver halide can also be used. Examples thereof include compounds that release a diffusible dye by an intramolecular nucleophilic substitution reaction described in U.S. Pat.No. 3,980,479 and the like, and an intramolecular reversion reaction of an isoxazolone ring described in U.S. Pat. Compounds that release diffusible dyes are included.

As described in U.S. Pat.No. 4,559,290, European Patent No. 220,746A2, U.S. Pat.No.4,783,396, Published Technical Report 87-6199, etc., a diffusible dye reacts with a reducing agent remaining without being oxidized by development. Non-diffusible compounds that release

Examples are U.S. Pat.Nos. 4,139,389 and 4,13
No. 9,379, JP-A-59-185333, compounds which release a diffusible dye by a nucleophilic substitution reaction in the molecule after reduction described in U.S. Pat.
No., JP-A-59-101649, JP-A-61-88257, RD24025 (19
1984), a compound that releases a diffusible dye by an electron transfer reaction in the molecule after being reduced.
No. 3,008,588A, JP-A-56-142530, U.S. Pat.
Nos. 893, 4,619,884, etc., compounds that release a diffusible dye by cleavage of a single bond after reduction, and release a diffusible dye after electron acceptance, as described in U.S. Pat. Nitro compounds, U.S. Pat.No. 4,609,61
Compounds which release a diffusible dye after electron acceptance described in No. 0 and the like are exemplified.

Also, as more preferred, EP 220,746A
No. 2, Published Technical Report 87-6199, U.S. Pat. No. 4,783,396, JP-A-63-201653, JP-A-63-201654, etc., in which NX bond (X is oxygen, sulfur or nitrogen) in one molecule. Represents an atom)
With a compound having an electron attractive group, compounds SO ₂ -X (X is as defined above) in one molecule described in Japanese Patent Application Sho 62-106885 having an electron attractive group, JP 63-271344 Compound having a PO-X bond (X is as defined above) and an electron-withdrawing group in one molecule described in JP-A-63-271341, and C-X 'bond in one molecule described in JP-A-63-271341. X 'is the same as X or -SO
_2- )) and a compound having an electron-withdrawing group. Further, the compounds described in Japanese Patent Application Nos. 62-319989 and 62-320771, which release a diffusible dye by cleavage of a single bond after reduction by a π bond conjugated to an electron accepting group can also be used.

Among them, a compound having an NX bond and an electron-withdrawing group in one molecule is particularly preferable. A specific example is European Patent No. 22
0,746A2 or compounds (1) to (3), (7) to (10), (12), (13) described in US Pat. No. 4,783,396.
(15), (23)-(26), (31), (32), (35),
(36), (40), (41), (44), (53)-(59),
(64), (70), Compounds (11) to of Published Technical Report 87-6199
(23).

Compounds that have a diffusible dye as a leaving group and release a diffusible dye upon reaction with an oxidized reducing agent (DD
R coupler). Specifically, British Patent No. 1,330,524, JP-B-48-39,165, U.S. Patent Nos. 3,443,940, and 4,47
Nos. 4,867 and 4,483,914.

Is reducible to silver halides or organic silver salts,
A compound that releases a diffusible dye when the partner is reduced (DRR
Compound). Since this compound does not need to use another reducing agent, it is preferable because there is no problem of image contamination due to oxidized decomposition products of the reducing agent. A representative example is U.S. Pat.No. 3,928,312
No. 4,053,312, No. 4,055,428, No. 4,336,32
No. 2, JP-A-59-65839, JP-A-59-69839, JP-A-53-3819
No. 51-104,343, RD17465, U.S. Pat.
No. 2, 3,728,113, 3,443,939, JP-A-58-1
Nos. 16,537, 57-179840 and U.S. Pat. No. 4,500,626. Specific examples of the DRR compound include the compounds described in the above-mentioned U.S. Pat. No. 4,500,626, columns 22 to 44. Among them, compounds (1) to (3) described in the above-mentioned U.S. Pat. (10)-(13), (16)-
(19), (28)-(30), (33)-(35), (38)-
(40), (42) to (64) are preferred. Also U.S. Pat.
The compounds described in 639,408, columns 37-39 are also useful.

Other examples of the above-mentioned couplers and dye-donating compounds other than the general formula [LI] include dye silver compounds in which an organic silver salt is combined with a dye (Research Disclosure Magazine, 1978, May 1978).
Monthly publications, pages 54 to 58), azo dyes used in the thermally developed silver dye bleaching method (US Pat. No. 4,235,957, Research Disclosure, April 1976, pages 30 to 32, etc.), leuco dyes (US Patent Nos. 3,985,565 and 4,022,617) can also be used.

Hydrophobic additives such as a dye-providing compound and a diffusion-resistant reducing agent can be introduced into a layer of a light-sensitive material by a known method such as the method described in US Pat. No. 2,322,027. In this case, JP-A-59-83154, JP-A-59-178451, and JP-A-59-178451.
-178452, 59-178453, 59-178454, 59-
High boiling organic solvents such as those described in JP-B-178455 and JP-B-59-178457 can be used in combination with a low-boiling organic solvent having a boiling point of 50 ° C to 160 ° C, if necessary.

The amount of the high boiling organic solvent is 1 g of the dye-donating compound used.
10 g or less, preferably 5 g or less. In addition, 1 cc or less of binder 1 g, further 0.5 cc or less, especially 0.
3cc or less is appropriate.

A dispersion method using a polymer described in JP-B-51-39853 and JP-A-51-59943 can also be used.

In the case of a compound which is substantially insoluble in water, it can be dispersed and contained as fine particles in a binder in the same manner as in the developer of the present invention or the basic metal compound which is hardly soluble in water.

In the present invention, a compound capable of activating development and simultaneously stabilizing an image can be used in the light-sensitive material. Specific compounds preferably used are described in U.S. Pat.
No. 626, columns 51-52.

In a system for forming an image by diffusion transfer of a dye, a dye fixing material is used together with a photosensitive material. The dye-fixing material may be in the form of being separately coated on a support separate from the photosensitive material, or may be in the form of being coated on the same support as the photosensitive material. The relationship between the photosensitive material and the dye-fixing material, the relationship with the support, and the relationship with the white reflective layer described in column 57 of US Pat. No. 4,500,626 can be applied to the present invention.

The dye fixing material preferably used in the present invention has at least one layer containing a mordant and a binder. As the mordant, those known in the field of photography can be used, and specific examples thereof include U.S. Pat.
-88256, mordants described on pages (32) to (41);
Nos. 2-244043 and 62-244036. Further, a dye-receiving polymer compound as described in US Pat. No. 4,463,079 may be used.

The dye-fixing material may be provided with an auxiliary layer such as a protective layer, a release layer, and an anti-curl layer, if necessary. It is particularly useful to provide a protective layer.

The constituent layers of the photosensitive material and the dye fixing material include a plasticizer,
A high boiling organic solvent can be used as a slipping agent or an agent for improving the releasability of the photosensitive material and the dye fixing material. Specific examples include those described in JP-A-62-253159, page (25) and JP-A-62-245253.

Furthermore, various silicone oils (all silicone oils from dimethyl silicone oil to modified silicone oil obtained by introducing various organic groups into dimethyl siloxane) can be used for the above purpose. For example,
"Modified silicone oil" issued by Shin-Etsu Silicone Co., Ltd.
Various modified silicone oils described in Technical Sample P6-18B,
Especially carboxy-modified silicone (trade name X-22-3710)
Etc. are effective.

The silicone oils described in JP-A-62-215953 and JP-A-63-46449 are also effective.

An anti-fading agent may be used in the light-sensitive material and the dye-fixing material. Anti-fading agents include, for example, antioxidants, ultraviolet absorbers, or certain metal complexes.

Examples of the antioxidant include chroman compounds, coumaran compounds, phenol compounds (eg, hindered phenols), hydroquinone derivatives, hindered amine derivatives, and spiroindane compounds. The compounds described in JP-A-61-159644 are also effective.

Examples of ultraviolet absorbers include benzotriazole-based compounds (US Pat. No. 3,533,794, etc.), 4-thiazolidone-based compounds (US Pat. No. 3,352,681), benzophenone-based compounds (JP-A-46-2784, etc.), and others. JP-A-54-
There are compounds described in JP-A-48535, JP-A-62-136641 and JP-A-61-88256. Further, ultraviolet absorbing polymers described in JP-A-62-260152 are also effective.

As metal complexes, U.S. Pat.Nos. 4,241,155 and 4,2
Nos. 45,018, columns 3-36, 4,254,195, columns 3-8, JP-A-62-174741 and JP-A-61-88256, pages (27) to (29),
There are compounds described in JP-A-63-199248, JP-A-62-234103 and JP-A-62-230595.

Examples of useful discoloration inhibitors are described in Japanese Patent Application No. 62-215272 (125).
~ (137).

An anti-fading agent for preventing fading of the dye transferred to the dye-fixing material may be contained in the dye-fixing material in advance, or may be supplied to the dye-fixing material from outside such as a photosensitive material. .

The above antioxidants, ultraviolet absorbers, and metal complexes may be used in combination with each other.

A fluorescent whitening agent may be used for the photosensitive material and the dye fixing material. In particular, it is preferable to incorporate a fluorescent whitening agent into the dye-fixing material or to supply it from outside such as a photosensitive material. For example, K. Veenkataraman ed., "The Chemistry of Synt
hetic Dyes, Vol. V, Chapter 8, and JP-A-61-143752. More specifically, a stilbene compound, a coumarin compound, a biphenyl compound, a benzoxazolyl compound, a naphthalimide compound, a pyrazoline compound, a carbostyril compound, and the like can be given.

The fluorescent whitening agent can be used in combination with an anti-fading agent.

Examples of the hardener used in the constituent layers of the light-sensitive material and the dye-fixing material include U.S. Patent No. 4,678,739, column 41, and JP-A-59-11665.
No. 5, 62-245261, 61-18942 and the like. More specifically, aldehyde hardeners (such as formaldehyde), aziridine hardeners, epoxy hardeners Vinyl sulfone hardeners (such as N, N'-ethylene-bis (vinylsulfonylacetamide) ethane), N-methylol hardeners (such as dimethylol urea), or polymer hardeners (Japanese Patent Laid-Open No. Sho 62) -234157, etc.).

Various surfactants can be used in the constituent layers of the light-sensitive material and the dye-fixing material for the purpose of coating aid, improving releasability, improving slipperiness, preventing static charge, and accelerating development. Specific examples of the surfactant are described in JP-A Nos. 62-173463 and 62-183457.

The constituent layers of the light-sensitive material and the dye-fixing material may contain an organic fluoro compound for the purpose of improving slipperiness, preventing static charge, and improving releasability. Representative examples of organic fluoro compounds include JP-B-57-9053, columns 8 to 17, JP-A-61-20944.
No. 62-135826, and hydrophobic surfactants such as fluorine surfactants described in JP-A No. 62-135826, or oily fluorine compounds such as fluorine oil or solid fluorine compound resins such as ethylene tetrafluoride resin. Can be

A matting agent can be used for the photosensitive material and the dye fixing material. As matting agents, in addition to the compounds described on page 29 of JP-A-61-88256 such as silicon dioxide, polyolefin or polymethacrylate, Japanese Patent Application No. 62-110064 such as benzoguanamine resin beads, polycarbonate resin beads and AS resin beads. And No. 62-110065.

In addition, the constituent layers of the photosensitive material and the dye fixing material include:
A heat solvent, an antifoaming agent, an antibacterial and antibacterial agent, colloidal silica, and the like may be included. Specific examples of these additives are disclosed in
No. 88256, pages (26) to (32).

In the present invention, an image formation accelerator can be used for the light-sensitive material and / or the dye-fixing material. Examples of the image formation accelerator include the promotion of a redox reaction between a silver salt oxidizing agent and a reducing agent, the promotion of a reaction such as the generation of a dye from a dye-providing substance or the decomposition or release of a diffusible dye, and the use of a photosensitive material layer. From the physicochemical function to bases or base precursors, nucleophilic compounds, high-boiling organic solvents (oils), thermal solvents, surfactants, silver Or, it is classified into a compound having an interaction with silver ions. However, these substance groups generally have a composite function and usually have some of the above-mentioned promoting effects. See U.S. Pat.
No. 9, columns 38-40.

Examples of the base precursor include salts of an organic acid and a base which are decarboxylated by heat, compounds which release amines by an intramolecular nucleophilic substitution reaction, Rossen rearrangement or Beckmann rearrangement, and the like. Specific examples thereof are described in U.S. Pat.
-65038 and the like.

In a system in which thermal development and transfer of a dye are performed simultaneously in the presence of a small amount of water, it is preferable to include a base and / or a base precursor in the dye-fixing material from the viewpoint of improving the storage stability of the photosensitive material.

In addition to the above, it is also possible to use a basic metal compound which is hardly soluble in water used in the present invention as a base precursor. In this method, EP 210,660, U.S. Pat.
As described in US Pat. No. 4,740,445, a combination of the basic metal compound and a compound capable of forming a complex with a metal ion constituting the basic metal compound (referred to as a complex-forming compound) is used. Further, compounds that generate a base by electrolysis described in JP-A-61-232451 can also be used as the base precursor. In particular, the former method is effective. The sparingly soluble metal compound and the complex forming compound are advantageously added separately to the light-sensitive material and the dye-fixing material.

In the light-sensitive material and / or dye-fixing material of the present invention, various development terminators can be used for the purpose of always obtaining a constant image with respect to fluctuations in processing temperature and processing time during development.

As used herein, the term "development terminator" refers to a compound that neutralizes a base or reacts with a base immediately after appropriate development to reduce the temperature of the base in the film and to suppress development by interacting with a compound that stops development or silver and silver salts. Compound. Specific examples include an acid precursor that releases an acid when heated, an electrophilic compound that causes a substitution reaction with a coexisting base when heated, or a nitrogen-containing heterocyclic compound, a mercapto compound, and a precursor thereof. More specifically, JP-A-62-253159 (31) to (32)
Page.

As a support for the light-sensitive material and the dye-fixing material of the present invention,
Those that can withstand the processing temperature are used. Generally, paper and synthetic polymers (films) are used. Specifically, polyethylene terephthalate, polycarbonate, polyvinyl chloride, polystyrene, polypropylene, polyimide, celluloses (for example, triacetyl cellulose) or a film containing pigment such as titanium oxide in these films, and polypropylene. For example, a mixed paper made from synthetic resin pulp such as polyethylene, a synthetic resin pulp such as polyethylene, and natural pulp, Yankee paper, baryta paper, coated paper (especially cast-coated paper), metal, cloth, glass and the like are used.

These can be used alone or as a support laminated on one or both sides with a synthetic polymer such as polyethylene.

In addition, the supports described in JP-A-62-253159, pages (29) to (31) can be used.

A hydrophilic binder, a semiconductive metal oxide such as alumina sol or tin oxide, carbon black, or another antistatic agent may be applied to the surface of these supports.

Methods of exposing and recording images on photosensitive materials include, for example, a method of directly photographing landscapes and people using a camera, a method of exposing through a reversal film or a negative film using a printer or a enlarger, and a method of copier. Scanning and exposing the original image through slits using an exposure device, etc., exposing the image information by emitting light from a light emitting diode or various lasers via electrical signals, CRT, liquid crystal display, electroluminescence display And a method of outputting the image to an image display device such as a plasma display and exposing the image directly or via an optical system.

As a light source for recording an image on a photosensitive material, as described above, natural light, a tungsten lamp, a light emitting diode, a laser light source, a U.S. Pat.
The light sources described in the column can be used.

Further, image exposure can be performed using a waveform conversion element in which a non-linear optical material and a coherent light source such as laser light are combined. Here, a nonlinear optical material is a material that can exhibit nonlinearity between polarization and electric field that appears when a strong optical electric field such as laser light is applied, such as lithium niobate and potassium dihydrogen phosphate (KDP ), Inorganic compounds represented by lithium iodate, BaB ₂ O _{4 and the} like, and urea derivatives and nitroaniline derivatives, for example, nitrolidine-N-oxide such as 3-methyl-4-nitropyridine-N-oxide (POM) Derivatives, JP-A-61-53462, 62
Compounds described in -210432 are preferably used. As a form of the waveform conversion element, a single crystal optical waveguide type, a fiber type, and the like are known, and any of them is useful.

The image information includes an image signal obtained from a video camera, an electronic still camera, and the like, a television signal represented by the Nippon Television Signal Standard (NTSC), and an image obtained by dividing cost into a large number of pixels such as a scanner. Signals, image signals created using a computer represented by CG and CAD can be used.

The photosensitive material and / or the dye-fixing material may have a form having a conductive heating element layer as a heating means for heat development or diffusion transfer of the dye. In this case, as the transparent or opaque heating element, those described in JP-A-61-145544 can be used. Note that these conductive layers also function as antistatic layers.

The heating temperature in the thermal development step can be developed at about 50 ° C. to about 250 ° C., and particularly about 80 ° C. to about 180 ° C. is useful. The dye diffusion transfer step may be performed simultaneously with the heat development, or may be performed after the heat development step. In the latter case, the heating temperature in the transfer step is such that the transfer can be performed in the range from the temperature in the heat development step to room temperature, but it is particularly preferable that the heating temperature is 50 ° C. or higher and about 10 ° C. lower than the temperature in the heat development step.

Dye transfer is caused only by heat, but a solvent may be used to promote dye transfer.

Further, as described in detail in JP-A-59-218443, JP-A-61-238056, etc., a method of performing development and transfer simultaneously or continuously by heating in the presence of a small amount of a solvent (particularly water) is also available. Useful. In this method, the heating temperature is preferably 50 ° C. or higher and the boiling point of the solvent or lower.
100 ° C or less is desirable.

Examples of the solvent used for promoting development and / or transferring the diffusible dye to the dye-fixing layer include water or a basic aqueous solution containing an inorganic alkali metal salt or an organic base (these bases include Those described in the section of the formation accelerator are used. In addition, a low-boiling solvent or a mixed solution of a low-boiling solvent and water or a basic aqueous solution can also be used. Further, a surfactant, an antifoggant, a sparingly soluble metal salt and a complex-forming compound may be contained in the solvent.

These solvents can be used in a method for imparting to the dye fixing material, the photosensitive material, or both. The amount used may be as small as not more than the weight of the solvent corresponding to the maximum swelling volume of the entire coating film (especially not more than the weight of the solvent corresponding to the maximum swelling volume of the entire coating film minus the weight of the entire coating film).

As a method for applying a solvent to the photosensitive layer or the dye fixing layer, there is, for example, a method described in JP-A-61-147244, page (26). Further, the solvent may be contained in the photosensitive material or the dye-fixing material or both in advance, for example, by enclosing the solvent in microcapsules.

In order to promote dye transfer, a method in which a hydrophilic thermal solvent which is solid at normal temperature and dissolves at high temperature is incorporated in the photosensitive material or the dye fixing material can be adopted. The hydrophilic thermal solvent may be incorporated in any of the photosensitive material and the dye fixing material,
It may be built in both. Also, the layer to be incorporated is an emulsion layer,
Any of an intermediate layer, a protective layer, and a dye-fixing layer may be used, but it is preferable to be incorporated in the dye-fixing layer and / or a layer adjacent thereto.

Examples of hydrophilic thermal solvents include ureas, pyridines, amides, sulfonamides, imides, alkenyls,
There are oximes and other heterocycles.

In order to promote dye transfer, a high-boiling organic solvent may be contained in the light-sensitive material and / or the dye-fixing material.

As a heating method in the development and / or transfer step, it is contacted with a heated block or plate, or in contact with a hot plate, hot presser, heat roller, halogen lamp heater, infrared and far infrared lamp heater, For example, passing through a high temperature atmosphere.

The method described in JP-A-61-147244, page 27, can be applied as a pressure condition and a method of applying pressure when the photosensitive material and the dye-fixing material are overlaid and brought into close contact with each other.

Any of a variety of thermal development equipment can be used to process the photographic elements of the present invention. For example, JP-A-59-75247, JP-A-59-75247
-17747, 59-181353, 60-18951, Shokai 6
An apparatus described in, for example, No. 2-25944 is preferably used.

<Example 1> How to prepare the emulsion (I) for the first layer will be described.

A well-stirred aqueous gelatin solution (20 g of gelatin, 1 g of potassium bromide, and OH (CH ₂ ) ₂ S (CH ₂ ) _{2 in} 800 ml of water
Solution (I), solution (II) and solution (III) below were simultaneously added at an equal flow rate over 30 minutes to 0.5 g of OH and kept at 50 ° C.). Thus, a monodispersed silver bromide emulsion to which a dye having an average grain size of 0.42 μ was adsorbed was prepared.

After washing with water and desalting, add 20 g of lime-processed ossein gelatin, adjust the pH to 6.4 and the pAg to 8.2, and keep the temperature at 60 ° C.
9 mg of sodium thiosulfate, 6 ml of 0.01% aqueous solution of chloroauric acid, 4
-Hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (190 mg) was added, and the mixture was chemically sensitized for 45 minutes. The yield of the emulsion was 635 g.

Next, the emulsion (II) for the third layer will be described.

A well-stirred aqueous solution (gelatin 20 in 730 ml of water)
g, potassium bromide 0.30 g, sodium chloride 6 g, and the following chemical A 0.015 g, and the mixture was kept at 60.0 ° C.). . After the addition of the solution (I), a methanol solution (III) of the following sensitizing dye was added. Thus, a monodispersed cubic emulsion adsorbing a dye having an average particle size of 0.45 μm was prepared.

After washing with water and desalting, add 20 g of gelatin, pH 6.4 and pAg.
After adjusting to 7.8, chemical sensitization was performed at 60.0 ° C. The chemicals used at this time were triethylthiourea 1.6 mg and 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene 100 m
In g, the aging time was 55 minutes. The yield of this emulsion was 635 g.

(Chemical A) Next, how to prepare the emulsion (III) for the fifth layer will be described.

A well-stirred aqueous gelatin solution (20 g of gelatin, 3 g of potassium bromide, and HO (CH ₂ ) ₂ S (CH ₂ ) _{2 in} 800 cc of water
0.3 g of S (CH ₂ ) ₂ OH was added thereto and kept at 55 ° C.), and the following solution (1) and solution (2) were added simultaneously over 30 minutes.
Thereafter, the following solution (3) and solution (4) were simultaneously added over 20 minutes. After the addition of the solution (3) was started, the following dye solution was added for 18 minutes from 5 minutes.

After washing and desalting, 20 g of lime-treated ossein gelatin was added to adjust the pH to 6.2 and the pAg to 8.5, and then sodium thiosulfate and 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene were added. And chloroauric acid was added for optimal chemical sensitization. In this way, 600 g of a monodisperse tetrahedral silver iodobromide emulsion having an average grain size of 0.40 μm was obtained.

Liquid dissolved in 160 cc of methanol.

Next, a method of preparing a gelatin dispersion of a dye-providing substance will be described. 20 g of yellow dye-providing substance (1) ^* ,
13.6 g of the electron donor (1) ^* and 10 g of tricyclohexyl phosphate were weighed, and 57 ml of ethyl acetate was added thereto.
The mixture was dissolved by heating to a uniform temperature. This solution, 110 g of a 10% solution of lime-processed gelatin, 65 ml of water and 1.7 g of sodium dodecylbenzenesulfonate were stirred and mixed, and then dispersed with a homogenizer at 10,000 rpm for 10 minutes. This dispersion is referred to as a yellow dye-providing substance dispersion.

The dispersion of the magenta and cyan dye-donating substances is the same as the dispersion of the yellow dye-donating substance, using the magenta dye-donating substance (2) ^* or the cyan dye-donating substance (3) ^*. I made it.

Thus, the color photosensitive material having a multilayer structure shown in Table 1 was obtained.
I made 101.

Developing agent (1) A multi-layered color light-sensitive material was prepared in the same manner except that the developing agent of the present invention was used in place of ^* .

Next, a method for preparing a fine particle dispersion of a developer will be described.

10 g of the developing agent (X-2) of the present invention and 0.5 g of the surfactant aerosol OT are added to 100 g of a 5% solution of gelatin, and the mixture is milled at 100 ° C. for 30 minutes with 100 g of glass beads having an average particle size of about 0.6 mm. Crushed. The glass beads were excessively separated to obtain an aqueous dispersion of the developer (X-2). At this time, the average particle size of the fine particles of the developer (X-2) is 0.5 μm,
The variation in the particle size was a standard deviation σ = 0.15.

For comparison, an experiment was conducted in which a developer was added as a methanol solution (2%) without preparing a dispersion.

 Next, a method of making the dye fixing material will be described.

 Dye fixing material R-1 having the composition shown in the table was prepared.

Silicone oil (1) Surfactant (1) Surfactant (2) Surfactant (3) Surfactant (4) Fluorescent whitening agent (1) 2,5 bis (5-tert-butylbenzoxazole (2)) thiophene surfactant (5) Water-soluble polymer (1) Sumikagel L5-H (manufactured by Sumitomo Chemical Co., Ltd.) Water-soluble polymer (2) Dextran (molecular weight 70,000) Mordant (1) High boiling point solvent (1) Hardener (1) Matsuto agent (1) Silica Matsuto agent (2) Benzoguanamine resin (average particle size: 15μ) Next, the developer used for photosensitive material 101 and the type, amount and layer of the hardly soluble metal compound were changed to those shown in Table 3. Except for the above, photosensitive materials 102 to 110 having exactly the same composition as 101 were respectively prepared.

Further, a part of the coating solution of each of the first to sixth layers of the photosensitive materials 101 to 110 was fractionated, kept in a solution state in a constant temperature water bath at 40 ° C., and allowed to stand with stirring for 12 hours. A light-sensitive material using the coating solution thus treated was also prepared. Each of these photosensitive materials is corresponding to
Named 1-210.

Using tungsten light bulbs of the color light-sensitive materials 101 to 110 and 201 to 210 having the above-mentioned multilayer structure, 5000 light is passed through B, G, R and gray color separation filters having continuously changing density.
Exposure for 1/10 seconds with lux.

While feeding the exposed photosensitive material at a linear speed of 20 mm / sec, water of 15 ml / m ² was supplied to the emulsion surface with a wire bar, and immediately thereafter, the image receiving material was superimposed on the film surface so as to be in contact with the film surface.

The film was heated for 15 seconds using a heat roller whose temperature was adjusted so that the temperature of the water-absorbed film became 85 ° C. Next, when peeled off from the image receiving material, clear images of blue, green, red, and gray corresponding to the B, G, R, and gray color separation filters were uniformly obtained on the image receiving material.

Table 4 shows the measurement results of the maximum density (Dmax) and the minimum density (Dmin) of cyan, magenta, and yellow in the gray portion.

Table 4 shows that the photosensitive materials 104, 107 and 110 of the present invention were prepared after keeping the coating solution in a dissolved state for 12 hours.
It can be seen that the photosensitive materials Nos. 4, 207 and 210 have the same photographic performance with low Dmin. This is a particularly necessary performance when a coating operation is performed for a long time during manufacturing. This object has been achieved in the light-sensitive material of the present invention.

Next, the photosensitive materials 101 to 110 are brought into a state of 45 ° C. and 70% humidity.
After keeping for 10 days, the same exposure and development processing were performed. Table 5 shows the results of measuring the density of the gray portion.

Table 5 shows that the photosensitive materials 104, 107, and 110 of the present invention have a smaller increase in Dmin after storage at 40 ° C. and 70% for 10 days than the photosensitive materials of the comparative examples.

Example 2 A light-sensitive material 301 having a multilayer structure as shown in Table 6 was prepared using the same emulsion and dye-donating substance as the color light-sensitive material 101 of Example 1.

Unless otherwise specified, the same additives as in the photosensitive material 101 were used.

 The organic silver salt emulsion was prepared as follows.

20 g of gelatin and 5.9 g of 4-acetylaminophenylpropiolic acid were dissolved in 1000 ml of a 0.1% aqueous sodium hydroxide solution and 200 ml of ethanol. This solution was kept at 40 ° C. and stirred. To this solution, a solution prepared by dissolving 4.5 g of silver nitrate in 200 ml of water was added over 5 minutes. Then the excess salt was removed by sedimentation. Thereafter, the pH was adjusted to 6.3 to obtain a 300 g yield of an organic silver salt dispersion.

Next, photosensitive materials 302 to 306 having exactly the same composition as 301 except that the type of developer, the amount of the hardly soluble metal compound, the amount added, and the added layer used in the photosensitive material 301 were changed to those shown in Table 7.

The photosensitive materials 301 to 306 were exposed and developed in the same manner as in Example 1. Furthermore, 301 to 306 were subjected to 10
After storage for days, the same treatment was performed. Dmax before and after storage,
Table 8 shows the measurement results of the Dmin value.

As in Example 1, the effect of the present invention is clear from <Table 8>.

Example 3 A black-and-white photosensitive material 401 having the following two-layer structure was prepared using Emulsion III of Example 1. [Table 9] Unless otherwise specified, the same additives as in the photosensitive material 101 were used.

Next, how to make an alkali generation sheet will be described.

Using the material used for the image receiving material R-1, an alkali generating sheet R-2 shown below was prepared.

Photosensitive materials 402 to 405 having exactly the same composition as 401 were prepared, except that the type of developer and the added layer of the photosensitive material 401 thus prepared were changed as shown in Table 11.

The light-sensitive materials 401 to 405 having the two-layer structure were exposed to 5000 lux for 1/10 second through a gray filter having a continuously changing density using a tungsten bulb.

While feeding the exposed light-sensitive material at a linear speed of 20 mm / sec, 10 ml / m ² of water was supplied to the emulsion surface with a wire bar, and immediately thereafter, the alkali-generating sheet and the film surface were overlapped so that the film surface was in contact therewith.

The film was heated for 15 seconds using a heat roller whose temperature was adjusted so that the temperature of the water-absorbed film became 85 ° C.

Next, the sheet was peeled off from the alkali-generating sheet and subjected to a fixing treatment in a commercially available fixing solution of FujiFix for 5 minutes. After further washing with running water for 20 minutes and drying, a negative image clearly corresponding to the gray filter density was obtained in the photographic material.

Further, in the same manner as in Examples 1 and 2,
After storing for 10 days at 70 ° C. and 70% humidity, the same treatment was performed.

Table 12 shows Dmax and Dmin values of the transmission density of the negative image.

[Table 12] clearly shows the effects of the present invention.

Claims (1)

(57) [Claims] 1. A photothermographic material comprising at least two or more coating layers, comprising at least a photosensitive silver halide, a binder, a developing agent and a basic metal compound insoluble in water on a support, As the developer, at least one developer having a solubility in water of 25 ° C. per water of 10 ⁻⁷ mol or more and 10 ⁻³ mol or less is finely dispersed in a binder, and contains the basic metal compound. A photothermographic material characterized by being contained in a coating layer different from the coating layer.