JP2001255620A - Heat developable photosensitive material with improved printout - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developable photosensitive material having good shelf stability at high humidity, nearly free from printout after development and having a scratch resistant film surface. SOLUTION: In the heat developable photosensitive material with a layer containing photosensitive silver halide grains, an organic silver salt and a reducing agent for the organic silver salt on the base, at least one polyhalomethane compound having a diffusion resistant group or an adsorptive group represented by formula (1) or (2) (where R1 and R2 are each an aliphatic group; R3 is -CN, -CH3, -CH2Br, -CHBr2 or -CBr3; W is a polyhalomethane group; and X is an anionic group) is contained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material which forms an image by thermal development, and more specifically, has high sensitivity, low fog and storage stability even when produced by solvent coating or aqueous coating. The present invention relates to a photothermographic material which is excellent and has excellent printout performance after development.

[0002]

2. Description of the Related Art In recent years, in the fields of medical care and printing, there has been a strong demand for a photothermographic material which does not contain waste liquid due to wet processing of the photosensitive material in view of environmental protection and workability. As this technology,
For example, US Patent Nos. 3,152,904 and 3,48
7,075 and D.C. “Dry Silver Photographic Materials (Dry Silver P) by Morgan
photographic Materials) ”(H
andbook of Imaging Materi
als, Marcel Dekker, Inc. Forty-eighth
1991) is well known. Since these photosensitive materials are usually developed at a temperature of 80 ° C. or higher, they are called photothermographic materials.

Conventionally, most photothermographic materials of this type have been manufactured by applying a solvent. The reason is that, in a photosensitive layer coated with a mixture of a developer and an organic silver salt by aqueous coating, the oxidation-reduction reaction gradually proceeds through water, and the fog performance and printout performance deteriorate. That's why.

[0004] For this reason, compounds that suppress the deterioration of fog performance and printout due to heat have been sought. In particular, as compounds that improve printout, polyhalomethane compounds are noted as being particularly effective. For example, US Pat. Nos. 3,874,946 and 4,452,8.
No. 85, No. 4,546,075, No. 4,756,99
9, 5,340,712, JP-A-54-165
No. 50-137126, JP-A-7-2781,
No. 9-265150 and European Patent No. 622,666.

[0005] However, even if these polyhalomethane compounds are used, the performance concerning printout is not sufficient. Performing the forced raw storability test lowers the image density and deteriorates the color tone. This tendency is particularly strong in a humid state.
In addition, the storage stability after the heat treatment was poor, and there were disadvantages such as a decrease in image density and a deterioration in color tone. Further, when a printout inhibitor is added, there is a problem that the film strength is deteriorated and the conductivity is deteriorated.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a high-quality image having a high image density and a preferable contrast, and furthermore, have a good storage stability under high humidity, and furthermore have a high image quality after development. Another object of the present invention is to provide a photothermographic material having extremely low printout. Another object is to provide a photothermographic material having a film surface resistant to scratches.

[0007]

The above object of the present invention is achieved by the following means.

1) photosensitive silver halide grains on a support,
In a photothermographic material having an organic silver salt and a layer containing a reducing agent for the organic silver salt, a polyhalomethane having a diffusion-resistant group or an adsorptive group represented by the general formula (1) or (2) A photothermographic material comprising at least one compound.

2) The photothermographic material as described in 1) above, wherein at least one of the diffusion-resistant groups of the polyhalomethane compound contains a fluorine atom.

3) The photothermographic material as described in 1) above, wherein the polyhalomethane compound is present in a layer containing wax, fine particles of inorganic oxide, or a fluorine compound represented by the general formula (3) or latex. .

4) The photothermographic material as described in 1) above, wherein the polyhalomethane compound is present in a layer containing a cellulose derivative or a polyvinyl alcohol derivative by applying a solvent.

Hereinafter, the present invention will be described in detail. In the photothermographic material, an organic silver salt, a reducing agent, a printout inhibitor and the like are contained in a photosensitive layer containing silver halide particles. After the photothermographic material is exposed and heat-developed, the printout inhibitor is left in a bright room or set on a light table or on a shark stain to suppress an increase in fog due to light. Is added to the photosensitive layer or a layer adjacent to the photosensitive layer. However, the use of an overactive printout inhibitor results in reduced sensitivity, reduced maximum density (Dmax), or reduced contrast. This is because the latent image in the silver halide grains is bleached due to the oxidizing power of the halogen atom in the printout inhibitor and becomes difficult to be developed, and when the oxidizing power is further increased, the developer is oxidized and the development is suppressed. It is possible. When the humidity is high, active radicals generated from the printout inhibitor are trapped and deactivated by moisture, so that fog is easily caused, which causes a decrease in sensitivity and a decrease in contrast, and the maximum density is lowered.

The present inventors have found that during storage of the photothermographic material, the diffusivity is low and has substantially no effect. A compound capable of suppressing a decrease in contrast and improving printout prevention after thermal development has been found. In addition, this compound does not weaken the film even if it is added to the photosensitive layer or a layer adjacent to the photosensitive layer or does not impair the conductivity, but can be used in combination with a material for strengthening the film or a material for improving the conductivity. Furthermore, they have found that the film can be strengthened and the conductivity can be improved.

Examples of the printout inhibitor compound used in the present invention include the polyhalogen compounds represented by the general formula (1) or (2).

In the general formula (1) or the general formula (2), R ¹ and R ² each represent an aliphatic group having 1 to 50 carbon atoms, and may have either an electron-withdrawing substituent or an electron-donating substituent. Can have. Examples of these substituents include an alkyl group having 1 to 25 carbon atoms which may be substituted (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, a cyclohexyl group) Etc.), halogenated alkyl groups (for example,
Trifluoromethyl group, perfluorooctyl group, etc.),
Cycloalkyl group (eg, cyclohexyl group, cyclopentyl group, etc.), alkynyl group (eg, propargyl group, etc.), aryl group (eg, phenyl group, etc.), heterocyclic group (eg, pyridyl group, thiazolyl group, oxazolyl group, imidazolyl Group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, suliphoranyl group, piperidinyl group, pyrazolyl group,
Tetrazolyl group, etc.), halogen atom (eg, chlorine atom, bromine atom, iodine atom, fluorine atom, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy group, pentyloxy group, cyclopentyloxy group, hexyloxy group) , Cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxy group) Carbonyl group), sulfonamide group (for example,
Methanesulfonamide group, ethanesulfonamide group, butanesulfonamide group, hexanesulfonamide group, cyclohexanesulfonamide group, benzenesulfonamide group, etc., sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group) Butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, phenylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), ureido group (for example, methylureido group,
Ethylureido group, pentylureido group, cyclohexylureido group, phenylureido group, 2-pyridylureido group, etc., acyl group (for example, acetyl group, propionyl group, butanoyl group, hexanoyl group, cyclohexanoyl group, benzoyl group, pyridinoyl) Carbamoyl group (eg, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, phenylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.) Amide group (for example, acetamido group, propionamido group,
Butanamide group, hexaneamide group, benzamide group, etc.), sulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, phenylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (eg, Amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, anilino group, 2-pyridylamino group, etc.), cyano group, nitro group, sulfo group, carboxyl group, hydroxyl group, oxamoyl group, etc. be able to. These groups may be further substituted with these groups.

W is a polyhalomethane group and the halogen can be selected from chlorine, iodine, bromine and fluorine, but a bromine atom-substituted tribromomethane group is most preferred. As the anion group represented by X, a halogen anion group is preferable, and a bromo anion group is more preferable.

The Rf group is bonded to a divalent linking group to form a group having 6 carbon atoms.
Represents an aliphatic group which may contain up to 50 diffusion-resistant groups or an adsorptive group containing at least one nitrogen or sulfur atom. A preferred group of the diffusion-resistant group is an aliphatic group which may have a linear or branched substituent, and particularly preferably contains a fluorine atom. As the adsorptive group, primary to tertiary containing nitrogen atom
Preferred are an amino group, an imidazole group, a triazole group, an oxazole group, a thiazole group, and a tetrazole group.

A represents a divalent linking group, for example, --CH _{2
-, - CF 2 -, =} CF -, - O -, - S -, - OCO
—, —CONH—, —SO ₂ NH—, a polyoxyalkylene group, a thiourea group, a polymethylene group, or a combination of these groups. Specific examples of such compounds are shown below, but the invention is not limited thereby.

[0019]

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[0020]

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[0021]

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[0022]

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[0023]

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The compounds represented by the above general formulas (1) and (2) used in the present invention may be an ester bond between a residue having a polyhalomethane group and an aliphatic group, a urethane bond,
It can be synthesized by introducing an amide bond, an ether bond, a carbonic acid group bond and the like. A method for synthesizing a polyhalomethane group can be produced by a method described in JP-A-6-340611 or the like, or a method described in a cited document or patent, in which an alkyl group is polyhalogenated with a halogenating agent. . A polyhalomethane compound bonded to a diffusion-resistant group can be synthesized by bonding a compound having a polyhalomethane group to the diffusion-resistant group.
The adsorptive group means a group that adsorbs to silver halide. In the case of single molecule adsorption, 1 to 100% of the surface area of silver halide grains.
Represents a group that can be adsorbed at an arbitrary value, and usually a group that can adsorb about 2 to 60% is preferable. In the case of multi-molecule adsorption, many molecules can be adsorbed even if the adsorption area is reduced. The adsorption amount was adjusted by adding a test compound to a liquid containing silver halide grains and adjusting the silver ion concentration to a constant (pAg5 to pAg5).
8), constant adsorption temperature of 5 to 30 ° C. and constant time (1 to 1)
0 hours), the amount actually adsorbed can be calculated by measuring the amount present in the solution (in water or organic solvent solution) without adsorption. Adsorption can be determined by, for example, adsorbing the compound of the present invention on silver halide over 3 hours at pAg6, 25 ° C., and determining the amount of adsorption.

The compound of the present invention can be added according to a known addition method. That is, it can be added by dissolving in alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone and acetone, and polar solvents such as dimethyl sulfoxide and dimethylformamide. In addition, sand mill dispersion and jet mill dispersion,
Ultrasonic dispersion or homogenizer dispersion may be used to form fine particles of 1 μm or less, dispersed in water or an organic solvent, and added. Although many techniques have been disclosed for the fine particle dispersion technique, they can be dispersed according to these techniques.

The polyhalomethane compound used in the present invention is preferably added to a layer in which additives such as silver halide, an organic silver salt and a reducing agent used in the present invention are present. It can be added to an adjacent layer, or can be added via an intermediate layer.

The polyhalomethane compound of the present invention may be finely dispersed in water or an organic solvent without being dissolved in water or a solvent to be added. In order to disperse the fine particles, the compound of the present invention is subjected to sand mill dispersion using glass beads or zirconia fine particle media, and a solution is spouted from a thin tube at a high speed to be crushed on a hard plate, or the liquid of the thin tube is impinged from two directions. Any method such as dispersing may be used. The fine particle dispersion preferably has a mean particle size of 1 nm or more and 10 μm or less in the aqueous solution, and preferably has a narrow particle distribution. In order to disperse in an aqueous solution, it is preferable that bubbles are not easily generated by stirring.

The polyhalomethane compound of the present invention is preferably added to the photosensitive layer or a layer adjacent to the photosensitive layer, but can also be added to the intermediate layer or the undercoat layer. The amount of the compound of the present invention is preferably 1 × 10 ⁻⁸ per mol of silver.
１1 × 10 ^-1 mol, particularly preferably 1 × 10 ^{-5 -1} × 1
0 ^-2 mol. When adding to a layer other than the silver-free photosensitive layer, the amount of addition can be determined in terms of unit area.
If the amount is too large, the sensitivity, contrast and maximum density are lowered, and if the amount is insufficient, it is difficult to obtain the effects of the present invention.

As the wax used in the present invention, synthetic and natural waxes can be widely used. In particular, carnauba wax obtained from the leaves of Brazilian palm trees is a typical example. The higher the content of the main component ester, the better, 84 to 8
The standard is 5%, but it is preferable to use one having a purity of 80% or more and 100% or less. The amount and method of addition can be based on the polyhalogen compound. If the amount of addition is too large, fog increases and contrast lowers.

The inorganic oxide fine particles used in the present invention are preferably those having high visible transparency and high conductivity. Preferred specific examples are tin oxide and zinc oxide. These fine particles may be doped with indium, platinum, palladium, antimony, phosphorus, and the like to 0.01 to 30,000 ppm. If the doping amount is small, it is difficult to obtain conductivity, and if the doping amount is large, it is difficult to obtain visible transparency. The average particle size is 1 nm or more,
It is preferably 10 μm or less. The addition amount is 0.01 mg / m ²
10 to 10 g / m ² is preferred, and 0.1 to 800 mg / m ² is more preferred.

In the general formula (3) used in the present invention, Pf is an aliphatic group having a fluorine atom, and the same group as Rf shown in the general formula (1) or (2) is applied. be able to. B represents a divalent linking group, and represents the same group as A represented by the general formulas (1) and (2). Preferred specific examples are shown below.

[0032]

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[0033]

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[0034]

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The compounds represented by the general formula (3) used in the present invention are described in JP-B-54-1284 and JP-B-59-22712.
No. 60-54292 and the like. A scheme of a method for synthesizing the exemplified compound 5-3 is shown below.

[0036]

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The method of adding the compound represented by formula (3) of the present invention can be performed according to a known addition method. That is, alcohols such as methanol and ethanol,
It can be added by dissolving in ketones such as methyl ethyl ketone and acetone, and polar solvents such as dimethyl sulfoxide and dimethylformamide. Further, fine particles of 1 μm or less can be dispersed in water or an organic solvent and added by sand mill dispersion, jet mill dispersion, ultrasonic dispersion or homogenizer dispersion. Although many techniques have been disclosed for the fine particle dispersion technique, they can be dispersed according to these techniques.

The amount of the compound represented by the general formula (3) is 0.1.
01 mg / m ^{2 to} 10 g / m ² and more preferably 0.1 m / m ²
g / m ^{2 to} 5 g / m ² , with the most preferred amount being 1 mg / m ^2.
m ^{2 to 2} g / m ² . An excessive addition amount is not preferable because it has adverse effects such as a decrease in sensitivity, softness, a decrease in the maximum density, a deterioration in chargeability, and a fragile film.

Various binders can be used as the binder for the photothermographic material of the present invention, for example, cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose, carboxyacetylcellulose, starch and its derivatives, polyvinyl alcohol, acetyl Polyvinyl alcohol,
Derivatives of a complex polyvinyl alcohol such as butyralized polyvinyl alcohol, acetylated and butyralized polyvinyl alcohol, and the like are included. In particular, the butyralization of hydroxyl groups of polyvinyl alcohol is 50 to 99%,
Butyralized and acetylated polyvinyl alcohol with 0.1-30% acetylation are preferred for use in solvent coating systems.

In the case of performing aqueous coating, a water-soluble polymer or a water-dispersible hydrophobic polymer (latex) can be used as a preferable polymer. For example,
Sodium polyacrylate, polyethylene oxide, acrylamide-acrylate copolymer, styrene-maleic anhydride copolymer, acrylonitrile-butadiene copolymer, vinyl chloride-vinyl acetate copolymer, styrene-butadiene-acrylic acid Copolymers and the like. These constitute an aqueous coating solution, but form a uniform polymer film at the stage of forming a coating film by drying after coating. When these are used, an organic reduced salt, silver halide, a reducing agent, and the like are mixed as an aqueous dispersion with these latexes to form a uniform dispersion, and then coated to form a photothermographic layer. I do. Upon drying, the latex coalesces the particles to form a uniform film.

Regarding the preferred polymer composition, the glass transition point is more preferably from -20 ° C to 80 ° C, particularly preferably from -5 ° C to 60 ° C. This is because if the glass transition point is high, the temperature for thermal development becomes high, and if the glass transition point is low, fogging tends to occur, resulting in a decrease in sensitivity and softness. The water-dispersed polymer is preferably dispersed as fine particles having an average particle diameter in the range of 1 nm to several μm. The water-dispersed hydrophobic polymer is called a latex, and among those widely used as a binder for aqueous coating, a latex that improves water resistance is preferable. The amount of latex used for obtaining water resistance as a binder is preferably as large as possible from the viewpoint of moisture resistance determined in consideration of coatability. 50% or more and 100% or less, more preferably 80% or more,
% Or more and 100% or less.

Specific examples of water-dispersed latex as a preferred polymer are shown below. Here, styrene is St, butadiene is Bu, methyl acrylate is MA, ethyl acrylate is EA, methyl acrylate is MMA, isononyl acrylate is INA, and cyclohexyl methacrylate is cyclohexyl methacrylate. CA, HEA for hydroxyethyl acrylate, HEMA for hydroxyethyl methacrylate, A for acrylic acid
A, MAA for methacrylic acid, IA for itaconic acid, AAm for acrylamide, St-S for styrenesulfonic acid, AMPS for acrylamide-2-methylpropanesulfonic acid amide, IP-S for isoprenesulfonic acid, 2-propenyl-4- Nonylphenoxyethylene oxide (n
= 10) Sulfonate is abbreviated as PF-S.

[0043]

[Table 1]

In the present invention, these polymer binders (in the case of latex, in terms of solid content) are used in an amount of 1/4 to 10 times the amount of silver, and the amount of silver added is 2.
In the case of 0 g / m ^2, the amount of the attached polymer is 0.5 to 20 g.
/ M ² . More preferably, the amount of silver is 1/2 to 7 times the amount of silver, and the amount of silver is 2.0 g.
If / m ^2, it is a 1.0~14g / m ^2. 4 with silver
If it is less than 1/1, the silver color tone will be significantly degraded and may not be usable, and if it is more than 10 times the amount of silver added, it will be soft and may not be usable.

The binder of the photothermographic material provides a site where each component of the photothermographic material such as silver halide, organic silver salt and reducing agent reacts. You need to proceed properly. Further, the diffusion-resistant polyhalomethane compound and the polyhalomethane compound having an adsorptive group of the present invention suppress volatilization and evaporation, and thus have an effect of reducing contamination in the apparatus.

Hereinafter, other components used in the photothermographic material will be described. Examples of the organic acid of the metal salt of the organic silver salt used in the present invention include fatty acids such as stearic acid, behenic acid and palmitic acid.

The photosensitive silver halide used in the photothermographic material of the present invention can be prepared by a method known in the field of photographic technology such as a single jet method or a double jet method, for example, by an ammonia method emulsion, a neutral method, or an acid method. And the like. After being prepared in this way, it can be mixed with other components of the present invention and introduced into the composition used in the present invention. In this case, in order to sufficiently bring the photosensitive silver halide into contact with the organic silver salt, for example, US Pat. Nos. 3,706,564 and 3,706, as protective polymers for preparing photosensitive silver halide. No. 565, No. 3,713,833, No. 3,748,143, British Patent No. 1,362,970, and other means using polymers other than gelatin, such as polyvinyl acetal, and British Patent No. 1 Means for Enzymatically Degrading the Gelatin of a Light-Sensitive Silver Halide Emulsion as described in U.S. Pat. No. 4,354,186, or Photosensitive Silver Halide Grains as described in U.S. Pat. No. 4,076,539. By preparing in the presence of a surfactant, various means such as a means for omitting the use of the protective polymer can be applied.

The silver halide functions as a high light-sensitive material, and it is preferable that the silver halide has a small particle size in order to suppress white turbidity after image formation and obtain good image quality. The average particle size is 0.1 μm or less, preferably 0.01 to 0.1 μm, particularly preferably 0.02 to 0.08 μm. The shape of the silver halide is not particularly limited, and may be cubic, octahedral, so-called normal crystals, non-normal crystals such as spherical, rod-shaped, and tabular grains. The silver halide composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide, and silver iodide.

The amount of silver halide is not more than 50%, preferably 0.1 to 10%, based on the total amount of silver halide and the organic silver salt described below.
It is 25%, more preferably 0.1 to 15%.

The photosensitive silver halide used in the photothermographic material of the present invention is also disclosed in British Patent No. 1,447,454.
As described in (1), when preparing an organic silver salt, a halogen component such as halide ion is made to coexist with an organic silver salt forming component, and silver ions are implanted into this to substantially simultaneously generate the organic silver salt. Can be generated.

As another method, a silver halide forming component is allowed to act on a solution or dispersion of an organic silver salt prepared in advance or a sheet material containing the organic silver salt, so that a part of the organic silver salt is exposed to light. It can also be converted to neutral silver halide.
The silver halide thus formed is in effective contact with the organic silver salt and exhibits a favorable effect. A silver halide-forming component is a compound that can react with an organic silver salt to produce a photosensitive silver halide, and which compounds are applicable and effective can be determined by the following simple test. Can be determined. That is, an organic silver salt is mixed with a compound to be tested, and if necessary, after heating, it is examined by an X-ray diffraction method whether there is a peak specific to silver halide. Silver halide-forming components confirmed to be effective by such tests include inorganic halides, onium halides, halogenated hydrocarbons, N-halogen compounds, and other halogen-containing compounds. Are U.S. Pat. Nos. 4,009,039;
457,075 and 4,003,749, British Patent No. 1,498,956 and JP-A-53-27027.
No. 53-25420.

These silver halide forming components are used in a small amount stoichiometrically with respect to the organic silver salt. Usually, the range is from 0.001 to 0.7 mol per mol of the organic silver salt,
Preferably it is 0.03-0.5 mol. Two or more silver halide forming components may be used in combination within the above range. Various conditions such as a reaction temperature, a reaction time, and a reaction pressure in the step of converting a part of the organic silver salt into silver halide using the above-mentioned silver halide forming component can be appropriately set according to the purpose of production. However, usually, the reaction temperature is −20 to 70 ° C., the reaction time is 0.1 second to 72 hours, and the reaction pressure is preferably set to the atmospheric pressure. This reaction is preferably performed in the presence of a polymer used as a binder described below. The amount of the polymer used at this time is 0.01 to 100 parts by mass, preferably 0.1 to 10 parts by mass per 1 part by mass of the organic silver salt.

The photosensitive silver halide prepared by the above-mentioned various methods includes, for example, sulfur-containing compounds, gold compounds,
Platinum compounds, palladium compounds, silver compounds, tin compounds,
Chemical sensitization can be achieved by a chromium compound or a combination thereof. The method and procedure of the chemical sensitization are described in, for example, US Pat. No. 4,036,650, British Patent 1,518,850, JP-A-51-22430,
Nos. 51-78319 and 51-81124. Also, when a part of the organic silver salt is converted to a photosensitive silver halide by a silver halide forming component, as described in U.S. Pat. An amide compound having a molecular weight may coexist.

In addition, these photosensitive silver halides include metals belonging to groups 6 to 11 of the periodic table of the elements, for example, Rh, Ru, Re, Ir, Os,
An ion such as Fe, a complex thereof, or a complex ion can be contained. These metal ions may be directly introduced into silver halide as a metal salt, but can be introduced into silver halide in the form of a metal complex or complex ion. As these metal complexes and metal complex ions, 6 represented by the following general formula:
Coordination complex ions are preferred. Specific examples of ligands include:
Halides (fluoride, chloride, bromide and iodide),
Examples include cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide, and aquo ligands, nitrosyl, thionitrosyl, and the like, and preferably aquo, nitrosyl, and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands.

One of these metal complexes or complex ions may be used, or two or more of the same and different metals may be used in combination. The content of these metal ions, metal complexes and complex ions, generally is suitably 1 × 10 ^-9 ~1 × 10 ^-2 mol per mol of silver halide, preferably 1 × 10 ^{- It is 8} to 1 × 10 ^-4 mol. Excessive addition is undesirable because it causes a decrease in sensitivity, softness, and a decrease in the maximum density. The compound that provides the ion or complex ion of these metals is preferably added during silver halide grain formation and incorporated into the silver halide grains. Preparation of silver halide grains, that is, nucleation, growth, and physical ripening It may be added at any stage before and after chemical sensitization, but is particularly preferably added at the stage of nucleation, growth, and physical ripening, more preferably at the stage of nucleation and growth. Preferably, it is added at the stage of nucleation. Upon addition, it may be added in several divided portions, may be uniformly contained in silver halide grains,
JP-A-63-29603, JP-A-2-306236
Nos. 3-167545, 4-76534, and 6
As described in, for example, JP-A-110146 and JP-A-5-273683, they can be contained in the particles with a distribution.

These metal compounds can be added by dissolving them in water or a suitable organic solvent (eg, alcohols, ethers, glycols, ketones, esters, amides). A method of adding an aqueous solution of a powder or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together to a water-soluble silver salt solution or a water-soluble halide solution during grain formation, or a method in which a silver salt solution and a halide solution are used. When they are mixed simultaneously, they are added as a third aqueous solution to prepare silver halide grains by a three-liquid simultaneous mixing method, a method in which a required amount of an aqueous solution of a metal compound is charged into a reaction vessel during grain formation, or a method in which halogen is added. There is a method in which another silver halide grain doped with a metal ion or a complex ion in advance at the time of preparing silver halide is added and dissolved. In particular, a method of adding an aqueous solution of a powder of a metal compound or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble halide solution. When adding to the particle surface, a required amount of an aqueous solution of a metal compound can be charged into the reaction vessel immediately after the formation of the particles, during or at the end of physical ripening, or at the time of chemical ripening.

In the present invention, a matting agent is preferably contained on the photosensitive layer side, and a matting agent is preferably disposed on the surface of the photosensitive material in order to prevent damage to the image after thermal development. Is preferably contained in a mass ratio of 0.5 to 30% based on all binders on the photosensitive layer side.

When a non-photosensitive layer is provided on the opposite side of the photosensitive layer with the support interposed therebetween, it is preferable that at least one layer on the non-photosensitive layer side contains a matting agent. In order to prevent fingerprint adhesion, it is preferable to provide a matting agent on the surface of the photothermographic material, and the matting agent is added in a mass ratio of 0.5 to 40 with respect to all binders in the layer on the side opposite to the photosensitive layer side. %.

The material of the matting agent used may be either an organic substance or an inorganic substance. For example, as inorganic substances, silica described in Swiss Patent No. 330,158, glass powder described in French Patent No. 1,296,995, etc., and alkali described in British Patent No. 1,173,181 etc. Earth metal, carbonates such as zinc and the like can be used as a matting agent. As organic substances, US Pat. No. 2,322,037
And starch derivatives described in Belgian Patent No. 625,451 and British Patent No. 981,198, polyvinyl alcohol described in JP-B-44-3643, and Swiss Patent No. 330,158. Polystyrene or polymethacrylate described in US Pat.
Organic matting agents such as polyacrylonitrile described in No. 079,257 and polycarbonate described in U.S. Pat. No. 3,022,169 can be used. The shape of the matting agent may be either a fixed shape or an irregular shape, but is preferably a fixed shape, and a spherical shape is preferably used. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. The particle size of the matting agent indicates the diameter converted into a sphere. The matting agent used preferably has an average particle size of 0.5 to 10 μm, more preferably 1.0 to 8.0 μm. The matting agent preferably has a variation coefficient of the particle size distribution of 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the coefficient of variation of the particle size distribution is a value represented by the following equation. (Standard deviation of particle size) / (Average value of particle size) × 100 These matting agents can be contained in any constituent layer. However, in order to achieve the object of the present invention, the matting agent is preferably viewed from the support. Outermost layer. The method of adding the matting agent may be a method in which the matting agent is dispersed in a coating solution in advance, or a method in which the matting agent is sprayed before the drying is completed after the coating solution is applied. When a plurality of types of matting agents are added, both methods may be used in combination. The addition amount of the matting agent can be appropriately determined at a level that does not cause a problem of haze depending on the size of the matting particles, but is 0.01 mg / m ^{2 to 1} g.
/ M ² . Excessive addition causes haze.

The photothermographic material of the present invention forms a photographic image by a heat development process, and comprises a reducible silver source (organic silver salt), a catalytically active amount of silver halide, a reducing agent, It is preferable that the photothermographic material generally contains a color tone agent which suppresses the color tone of silver in a state of being dispersed in an organic binder matrix. Although the photothermographic material of the present invention is stable at room temperature, it has a high temperature after exposure (for example, 80 to 80).
140 ° C.). Heating generates silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. The silver formed by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image. This reaction process
The process proceeds without supplying a processing liquid such as water from the outside.

The photothermographic material of the present invention has at least one photosensitive layer on a support. Although only the photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer thereon.

In order to control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer on the same side as the photosensitive layer and / or an antihalation dye layer, so-called backing layer, may be formed on the opposite side. Alternatively, a dye or a pigment may be contained in the photosensitive layer.

The photothermographic material of the present invention may contain an antifoggant. As effective antifoggants, mercury compounds known from, for example, U.S. Pat. No. 3,589,903 are environmentally undesirable. For this reason, non-mercury antifoggants have been studied for a long time. Non-mercury antifoggants include, for example, US Pat. No. 4,546,07.
Nos. 5,452,885 and JP-A-59-572.
No. 34 is preferred.
Examples of preferred antifoggants include JP-A-9-9055
Compounds described in No. 0 paragraph numbers [0062] to [0063]. Further, other suitable antifoggants are disclosed in U.S. Pat. No. 5,028,523 and EP 6060.
0,587, 605,981, 631,176
Issue.

The photothermographic materials of the present invention include, for example, JP-A-63-159814, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651, and JP-A-6-259561.
3-304242, 63-15245, U.S. Pat. Nos. 4,639,414, 4,740,455, 4,741,966, 4,751,175, and 4,835. No. 096 can be used.

Useful sensitizing dyes for use in the present invention include, for example, Research Disclosure 1764
3IV-A (p.23, December 1978), 1843
It is described in the literature described or cited in section 1X (August 1979, p. 437). In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected. For example, Japanese Patent Application Laid-Open No. 9-3407
No. 8, 9-54409 and 9-80679 are preferably used.

In the present invention, if necessary, a sensitizer, an organic or inorganic filler, a surfactant, a stain inhibitor, a UV absorber, an antioxidant, a water-proofing agent,
Dispersants, stabilizers, plasticizers, coating aids, defoamers, fluorescent dyes, metal salts of higher fatty acids, and the like may be added.

The photosensitive layer may be composed of a plurality of layers, or may be composed of a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / high-sensitivity layer for adjusting the gradation. Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other layers.

As the support, a support such as paper, synthetic paper, non-woven fabric, metal foil, plastic film and the like can be used, and a composite sheet combining these can be used arbitrarily.

The coating solution can be obtained as follows. A dispersion in which the polyhalomethane compound of the present invention is dispersed with a binder, a dispersion in which an organic silver salt, silver halide and a developer are dispersed with a binder, and a dispersion or a solution in which necessary additives are further dispersed with the binder Are mixed to obtain a coating solution. When this coating solution is applied on a support and dried, a photothermographic material can be obtained. As a coating method to be used, various methods such as a slide hopper method, a wire bar method, a roll coater method and a vacuum extrusion method can be appropriately selected.

In the present invention, when water-based coating is performed using, for example, an aqueous solution of a latex or a binder as a binder, the water-based coating method means that the ratio of the organic solvent to the water in the coating liquid composition is 0% or more in the preparation of the coating liquid. , 40% or less, preferably 20% or less, more preferably 10% or less, and most preferably 5% or less. In coating such an aqueous coating solution, the reaction of the polyhalomethane compound of the present invention, which leads to fogging progress when the coating is stagnant, is greatly suppressed as described above. The properties can be improved.

In the photothermographic material of the present invention, the exposure is preferably carried out by laser scanning exposure. However, the laser scanning in which the angle between the exposed surface of the photothermographic material and the scanning laser beam does not become substantially perpendicular is performed. It is preferable to use an exposure machine. Here, “not substantially vertical” means that the angle is closest to vertical during laser scanning, preferably 55 degrees or more and 88 degrees or less, more preferably 6 degrees or less.
0 degrees or more and 86 degrees or less, more preferably 65 degrees or more and 8
4 degrees or less, most preferably 70 degrees or more and 82 degrees or less.

The beam spot diameter on the photosensitive material exposed surface when the laser beam scans the photothermographic material is preferably 200 μm or less, more preferably 100 μm or less. It is preferable that the spot diameter is small in that the shift angle of the laser incident angle from a right angle can be reduced. still,
The lower limit of the beam spot diameter is 10 μm. By performing such laser scanning exposure, it is possible to reduce image quality deterioration related to reflected light such as occurrence of unevenness like interference fringes.

The exposure in the present invention is also preferably performed using a laser scanning exposure machine that emits a scanning laser beam that is a vertical multi. As compared with the scanning laser beam in the longitudinal single mode, image quality deterioration such as generation of interference fringe-like unevenness is reduced. To achieve vertical multiplication, a method of applying high-frequency superposition using return light due to multiplexing is preferable. In addition, the vertical multi means that the exposure wavelength is not single, and the distribution of the exposure wavelength is usually 5 nm or more, preferably 10 nm or more. The upper limit of the exposure wavelength distribution is not particularly limited, but is usually about 60 nm.

[0075]

EXAMPLES The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

Example 1 [Preparation of Subbed Photographic Support] <Preparation of PET Subbed Photographic Support> Commercially available biaxially stretched heat-fixed 175 μm thick optical density 0.170
(Measured with a Konica Corporation densitometer PDA-65), a corona discharge treatment of 8 W / m ² · min. Was applied to both sides of the polyethylene terephthalate film colored blue, and the following undercoating solution a-1 was dried on one side. It is applied to a thickness of 0.8 μm and dried to form an undercoat layer A-1. On the opposite surface, an undercoat coating solution b-1 shown below is dried to a thickness of 0.8 μm.
And dried to obtain an undercoat layer B-1.

<< Undercoat Coating Solution a-1 >> Butyl acrylate (30% by mass) t-butyl acrylate (20% by mass) Styrene (25% by mass) Copolymer latex liquid of 2-hydroxyethyl acrylate (25% by mass) (Solid content 30%) 270 g hexamethylene-1,6-bis (ethylene urea) 0.8 g Finish to 1 L with water << Undercoat coating solution b-1 >> Butyl acrylate (40% by mass) Styrene (20% by mass) Glycidyl Acrylate (40% by mass) copolymer latex liquid (solid content 30%) 270 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Finished to 1 L with water Subsequently, undercoat layer A-1 and undercoat On the upper surface of layer B-1,
A corona discharge of 8 W / m ² · min. Was performed, and the following lower coating liquid a-2 was coated on the lower coating layer A-1 with a dry film thickness of 0.1 μm.
The lower coating layer B-2 is coated with the following coating liquid b-2 on the lower coating layer B-1 so as to have a dry film thickness of 0.8 μm. Coated as B-2.

<< Coating Solution for Undercoating Layer a-2 >> Gelatin Mass of 0.4 g / m ² Silica Particles (Average Particle Size 3 μm) 0.1 g Finishing to 1 L with Water << Coating Solution for Undercoating Layer b-2 >> Styrene Butadiene copolymer latex solution (solid content 20%) 80 g Polyethylene glycol (weight average molecular weight 600) 6 g Finish up to 1 L with water (Preparation of photosensitive silver halide emulsion A) In 900 ml of water, 7.5 g of inert gelatin and bromide Potassium 10m
g was dissolved and the temperature was adjusted to 35 ° C. and the pH to 3.0.
370 ml of an aqueous solution containing 74 g of silver nitrate and 370 ml of an aqueous solution containing potassium bromide and potassium iodide in a molar ratio of (98/2) equivalent to the aqueous solution were added over 10 minutes by a controlled double jet method while maintaining the pAg at 7.7. did. Thereafter, 4-hydroxy-6-methyl-1,3,3
a, Add 0.3 g of 7-tetrazaindene, adjust the pH to 5.0 with NaOH, and adjust the average particle size to 0.06 μm;
Cubic silver iodobromide grains having a coefficient of variation in grain size of 8% and a [100] face ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, and after desalting treatment, 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and the pAg to 7.5 to obtain a photosensitive silver halide emulsion A.

(Preparation of Powdered Organic Silver Salt A) 111.4 g of behenic acid and 83.8 of arachidic acid were added to 4720 ml of pure water.
g and 54.9 g of stearic acid were dissolved at 80 ° C. Next, while stirring at a high speed, 540.2 ml of a 1.5 M aqueous sodium hydroxide solution was added, and the mixture was sufficiently stirred. Next, 6.9 ml of concentrated nitric acid was added, and the mixture was cooled to 55 ° C. to obtain a sodium organic acid solution. The temperature of the organic acid sodium solution is 55 ° C.
While keeping the above photosensitive silver halide emulsion A (silver 0.1.
038 mol) and 450 ml of pure water were added and stirred for 5 minutes. Next, 760.6 ml of a 1M silver nitrate solution was added over 2 minutes, and the mixture was further stirred for 20 minutes, and water-soluble salts were removed by filtration. Thereafter, the conductivity of the filtrate was 2 μS / cm.
Washing with deionized water and filtration were repeated until the concentration reached, and water was added to a predetermined concentration to finish.

(Preparation of Coating Solution for Photosensitive Layer) The following layers were successively formed on the undercoated support to prepare a sample. In addition, each drying was performed at 75 ° C. for 1 minute.

Coating of Photosensitive Layer Side The photosensitive layer was prepared by adding an aqueous dispersion of the following composition to water to prepare a coating solution. A preparation solution of silver halide and an organic silver salt in an amount of 1.2 g / m ² as a silver amount was mixed with a polymer binder.

Polyvinyl alcohol (PVA205 manufactured by Kuraray Co., Ltd.) 5.6 g / m ² Sensitizing dye A 2 mg / m ² Antifoggant 1: Pyridinium hydrobromide perbromide 0.3 mg / m ² Antifoggant 2: isothiazolone 1.2 mg / m ² antifoggant 3: 5-methyl-2-methylthio benzimidazole 120 mg / m ² polyhalomethane compound (described in Table 2) 2.2 × 10 ^-4 mol / m ² developer (1,1 -Bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane) 3.3 mmol / m ² Surface protective layer: An aqueous solution or dispersion of the following composition was added to water. The prepared coating solution was applied and dried so as to have the following amount.

Inert gelatin 1.2 g / m ² 4-methylphthalic acid 0.72 g / m ² Tetrachlorophthalic acid 0.22 g / m ² Tetrachlorophthalic anhydride 0.5 g / m ² Silica matting agent (average particle size) 0.5 g / m ² 1,2- (bisvinylsulfone acetamide) ethane 0.3 g / m ² polyhalomethane compound (described in Table 2) 1.1 × 10 ⁻⁴ mol / m ² Added to protective layer and photosensitive layer The same polyhalomethane compound was used.

Back layer surface coating Back layer: A coating solution prepared by adding an aqueous solution or aqueous dispersion of the following composition to water was applied and dried so as to have the following coating amount.

Polyvinyl alcohol (PVA205: manufactured by Kuraray Co., Ltd.) 2.0 g / m ² Dye C 70 mg / m ² Back layer protective film Inert gelatin 0.8 g / m ² Matting agent (PMMA: average particle size 3 μm) 02 g / m ² surfactant (N-propyloctylsulfonamidoacetic acid) 0.02 g / m ² 1,2- (bisvinylsulfonamido) ethane 0.02 g / m ²

[0086]

Embedded image

<< Evaluation of Photographic Properties >> The conditions for exposure and development were as follows: the photothermographic material was exposed with a laser sensitometer having a 780 nm semiconductor laser, and then subjected to heat development at 120 ° C. for 8 seconds using a heat drum. At that time, exposure and development were performed in a room conditioned at 25 ° C. and a relative humidity of 50%.
The sensitivity and fog of the obtained image were evaluated by an automatic densitometer. The sensitivity was evaluated by the reciprocal of the ratio of the exposure amount giving a density 0.3 higher than the fog. For the measurement of fog, the unexposed sample was thermally developed and the density was measured. The contrast was calculated from the slope of the tangent line on the photographic characteristic curve giving a density of 1.5.

For the measurement of the maximum density, the density at a point where an exposure amount 10 times the exposure amount giving a density of 1.5 was measured. The printout performance was evaluated by subjecting the coated and dried sample of the heat-developable material to exposure and development after storage in a room at 23 ° C. and 50% humidity for 3 days after application, and dividing the resulting developed sample into two parts. Was left on a 400 lux light table with a 60 W daylight fluorescent lamp for 6 hours to determine the fog value printed out, and the difference from the fog value of the sample stored in the other dark room was determined. The smaller the difference in fog, the more appropriate the printout.

In the moisture resistance test, a sample of the heat-developable material coated and dried was stored in a room at 23 ° C. and a relative humidity of 50% for 3 days, and then the sample was divided into two parts, one of which was 45 ° C. and the relative humidity was 8
The sample was stored in a 0% room for 3 days (a sample stored at a high humidity), and one of them was stored in a room at 23 ° C. and a relative humidity of 50% (a normal humidity sample). The two stored samples were exposed and developed, and the difference in fog and the change in contrast were determined. The smaller the difference between the fog and the contrast, the higher the moisture resistance.
The compound used for comparison is Stabilizer 4 in Table 1 of the examples of JP-A-6-340611, and has a structure of C ₈ F ₁₇ CBr ₂ S.
O ₂ CBr ₃ . The results are shown in Table 2.

[0090]

[Table 2]

Table 2 shows that when the polyhalomethane compound of the present invention is used, printout after development is suppressed and excellent results in moisture resistance can be obtained. In particular, it is found that the introduction of a fluorine atom into an adsorptive group, a diffusion-resistant group, or an aliphatic group gives good results. Confirmation of the adsorptivity shown in Table 2 shows that propanol of pAg6 and water 1: 1
It was confirmed by a matrix-assisted mass spectrometer that 5% or more of the surface area of silver halide grains was adsorbed in a 25 ° C. aqueous solution.

Example 2 A photothermographic material was prepared in the same manner as in Example 1, except that, when the protective layer was prepared, tin oxide fine particles doped with 18 ppm of phosphorus and having an average particle diameter of 20 nm were 100 mg / m ² and carnauba wax was used. A sample was prepared by adding 78 mg / m ² or 1.6 × 10 ⁻⁴ mol / m ^{2 of the} compound represented by the general formula (3). The scratch resistance of the obtained sample was examined.

The scratch resistance was evaluated by visually rubbing the sample while applying a load of 5 kPa with a roller having a depth of 3 μm and having irregularities. Table 3 shows the results of the evaluation, in which the level with no flaw was 5, the level with the most flaws was 1, and the level which was moderate and had no practical problem was 3.

[0094]

[Table 3]

From the results of Example 2, it can be seen that the use of the compound of the present invention and a wax, a metal oxide, or the compound represented by the general formula (3) improves printout properties and scratch resistance.

Example 3 A sample was prepared in the same manner as in Example 1, except that a water-dispersible hydrophobic latex (described in Table 1) was used instead of the polyvinyl alcohol used for the photosensitive layer. Carboxyacetylcellulose was used instead of inert gelatin. The photographic performance of the obtained sample was evaluated in the same manner as in Example 1. Table 4 shows the obtained results.

[0097]

[Table 4]

Table 4 shows that when the polyhalomethane compound and the latex of the present invention were used, printout after development was suppressed and the moisture resistance was excellent.

Example 4 A sample was prepared in the same manner as in Example 1, except that the binder on the photosensitive layer side was replaced with a compound having the following formulation, and coating was performed with a solvent system. The prescription on the photosensitive layer side is shown below.

Coating of Photosensitive Layer Side The photosensitive layer was prepared by preparing a coating solution in which the following composition was dissolved in methyl ethyl ketone. A preparation solution of silver halide and an organic silver salt in an amount of 1.3 g / m ^{2 in} terms of silver was mixed with a polymer binder.

Polyvinyl butyral PBV-1 as a binder 5.6 g / m ² Sensitizing dye A 2 mg / m ² Antifoggant 1: Pyridinium hydrobromide perbromide 0.3 mg / m ² Antifoggant 2: Isothiazolone 1.2 mg / m m ² antifoggant 3: 5-methyl-2-methylthiobenzimidazole 120 mg / m ² polyhalomethane compound (described in Table 5) 2.2 × 10 ⁻⁴ mol / m ² developer (1,1-bis (2- (Hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane) 3.3 mmol / m ²

[0102]

Embedded image

Surface protective layer: A coating solution prepared by dissolving the following composition in methyl ethyl ketone was applied and dried so that the following amount was obtained.

Carboxyacetyl cellulose 1.2 g / m ² 4-methylphthalic acid 0.72 g / m ² Tetrachlorophthalic acid 0.22 g / m ² Tetrachlorophthalic anhydride 0.5 g / m ² Silica matting agent (average particle size) 0.5 g / m ² hexamethylene diisocyanate 0.3 g / m ² polyhalomethane compound (same type as the photosensitive layer and described in Table 5) 1.2 × 10 ⁻⁴ / m ² The same was done. Table 5 shows the results.

[0105]

[Table 5]

From Table 5, it can be seen that, in the solvent-based coating using a cellulose-based and polyvinyl butyral-based binder, the use of the compound of the present invention is excellent in moisture resistance and printout suitability.

[0107]

According to the present invention, a photothermographic material having excellent photographic performance such as sensitivity, fog, maximum density and contrast, excellent storage stability under high humidity, and excellent printout performance after development can be obtained. Could be provided.

Claims (4)

[Claims] 1. A photothermographic material comprising a support containing a layer containing photosensitive silver halide grains, an organic silver salt and a reducing agent for the organic silver salt, wherein the photothermographic material of the formula (1) or (2) A photothermographic material comprising at least one polyhalomethane compound having a diffusion-resistant group or an adsorptive group represented by the formula: Embedded image (Wherein, R ¹ and R ² represent an aliphatic group, and R ³ represents —CN, —C
_{H 3, -CH 2 Br, -CHBr} 2, the respective groups of -CBr _3, W a is polyhalomethane group, X represents an anion group. A represents a divalent linking group, and Rf represents a group which forms an adsorptive group or a diffusion-resistant group by bonding to A. ) 2. The photothermographic material according to claim 1, wherein at least one of the diffusion-resistant groups of the polyhalomethane compound contains a fluorine atom. 3. The photothermographic material according to claim 1, wherein the polyhalomethane compound is present in a layer containing wax, inorganic oxide fine particles, a fluorine compound represented by the general formula (3) or latex. General formula (3) Pf-B-Pf (wherein, Pf represents an aliphatic group having a fluorine atom;
Represents a divalent linking group. ) 4. The photothermographic material according to claim 1, wherein the polyhalomethane compound is present in a layer containing a cellulose derivative or a polyvinyl alcohol derivative by applying a solvent.