JP2000131795A - Heat developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent transport failure in the processing of a heat developable photosensitive material particularly in an automatic processing machine, to suppress density changes after heat development in the case of long-term storage and to prevent a change in sensitivity and occurrence of fog independently of processing temperature. SOLUTION: In a heat developable photosensitive material having at least one image forming layer containing organic silver salt grains on the substrate and containing a reducing agent in a photographic constituent layer on the image forming layer side, at least one compound of the formula Rf-(A)n-Rf' [where each of Rf and Rf' is a group having at least one fluorine-containing aliphatic group, A is a group having at least one alkylene oxide group, and (n) is an integer of >=1. Rf and Rf' may be the same or different, but when Rf is CmF2m+1SO3-.NH3+, Rf and Rf' are the same. The symbol (m) stands for an integer of >=] 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 having excellent transportability and aging properties and having stable developing properties, and more particularly to a black-and-white photothermographic material.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making and medical treatment, waste liquids caused by wet processing of image forming materials have become a problem in terms of workability. Weight loss is strongly desired. Therefore, there is a need for a technique relating to photothermographic materials for photographic technology, which enables efficient exposure with a laser imagesetter or laser imager and can form a high-resolution, clear black image. As this technique, for example, a photothermographic material comprising an organic silver salt, photosensitive silver halide particles and a reducing agent on a support as disclosed in U.S. Pat. No. 3,152,904 is known. It is also known that an automatic developing machine for thermally developing a photothermographic material does not require a large processing tank as in the case of wet development, and thus has the advantage of being compactly designed.

[0003]

Recently, in the field of medicine, CT (Computed Tomography) images and MRI (Magnetic Resonance I) have been developed.
2. Description of the Related Art It has been practiced to output data, such as an image, captured by a digital device to a film by an imager and perform a diagnosis on an image developed and processed. The use of the above photothermographic materials for the output of these imagers requires less machine installation area, simplicity of processing operations,
It is also excellent from the viewpoint of environmental protection. However, since these photothermographic materials are usually processed at a high temperature of 100 ° C. or higher, transport failure may occur in an automatic developing machine having a thermal developing section, and when stored for a long time, the density fluctuation after thermal development may be large. In addition, there has been a problem that thermal development conditions such as temperature and time fluctuate, and in particular, performance such as sensitivity and fog when the processing temperature is low greatly fluctuates.

As a technique for solving these problems, Japanese Patent Application Laid-Open Nos. 7-173225 and 9-5925 disclose the use of a specific fluorine-based polymer to improve coating properties. No. 233268 discloses the use of a specific fluorine-based antistatic agent.
No. 81636 discloses that a specific fluorine-based polymer is used for improving coatability and storage stability.
It was not enough to solve the above problems.

The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent poor conveyance in processing a photothermographic material, particularly when processing with an automatic developing machine.
Further, when stored for a long period of time, it is possible to suppress the density fluctuation of the image after the heat development, and to eliminate the fluctuation of the sensitivity and fog without depending on the processing temperature.

[0006]

The above object of the present invention has been attained by the following constitutions.

1) A photothermographic material comprising at least one image forming layer having organic silver particles on a support and a reducing agent contained in a photographic component layer on the side having the image forming layer, A photothermographic material comprising at least one compound represented by the following general formula (1).

Formula (1) Rf- (A) _n -Rf 'wherein Rf and Rf' are groups having at least one fluorine-containing aliphatic group, A is a group having at least one alkylene oxide group, n Represents an integer of 1 or more, and Rf,
Rf 'may be the same or different. Where Rf is C _m F
_2m + 1 SO ₃ ^- when representing a · NH ₃ ⁺ groups Rf and Rf 'are the same. m represents an integer of 1 or more.

(2) At least one compound represented by the above general formula (1) is contained in at least one of the image forming layer side and the side opposite to the image forming layer.
The photothermographic material according to the above.

3) The photothermographic material according to 1) or 2), wherein at least one layer on the side of the image forming layer contains a photosensitive silver halide.

4) The photothermographic material according to 1), 2) or 3), wherein at least one layer on the image forming layer side contains an oxidizing agent.

5) The photothermographic material according to 4), wherein the oxidizing agent is a compound represented by the following general formula (2).

[0013]

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In the formula, A represents an aliphatic group, an aromatic or heterocyclic group, and X ₁ , X ₂ and X ₃ each represent a hydrogen atom or an electron-withdrawing group, which may be the same or different. Y represents a divalent linking group.

[0015] The gist of the present invention is that when the photothermographic material is subjected to thermal development processing, transport failure due to high temperature processing, increase in density fluctuation after thermal development when stored for a long time, or when processing temperature is low. In improving the problem of fluctuations in sensitivity and fogging performance, a novel structure having a specific structure on the side of the image forming layer having organic silver particles and / or on the side opposite to the side having the image forming layer across the support It has been found that this can be achieved by adopting a configuration in which a suitable fluorine-based surfactant is contained. That is, it has been found that when the fluorine-based surfactant is used in the constituent layer of the photothermographic material, various problems during the heat development can be improved, and as a result, an excellent image can be obtained. . The use of the fluorine-based surfactant not only solves the above problem, but also surprisingly has an accompanying effect that the adhesion between the support and the constituent layers can be enhanced.

As far as the point of using a fluorinated surfactant in a photothermographic material is concerned, a technique used for the purpose of improving coating properties and antistatic properties is disclosed in JP-A-60-2449.
No. 45, JP-A-7-173225 and JP-A-7-23
No. 3268. JP-A-9-281
No. 636 proposes to use a specific fluorine-based surfactant in a photothermographic material to reduce the fog fluctuation during storage over time.

Hereinafter, the present invention will be described in detail.

The present invention relates to a photothermographic material comprising at least one image forming layer having organic silver particles on a support, and a reducing agent contained in a photographic component layer on the side having the image forming layer. And at least one compound represented by the following general formula (1).

Formula (1) Rf- (A) _n -Rf 'wherein Rf and Rf' are groups having at least one fluorine-containing aliphatic group, A is a group having at least one alkylene oxide group, n Represents an integer of 1 or more, and Rf,
Rf 'may be the same or different. Where Rf is C _m F
_2m + 1 SO ₃ ^- when representing a · NH ₃ ⁺ groups Rf and Rf 'are the same. m represents an integer of 1 or more.

The compound represented by formula (1) will be described in more detail.

The fluorine-containing aliphatic group for Rf and Rf 'is linear, branched or cyclic or a combination thereof (for example, an alkylcycloaliphatic group). Preferred fluorine-containing aliphatic group, a fluoroalkyl group having 1 to 20 carbon atoms _{(e.g., -C 4 H 9, -C 8} H 17), a sulfo fluoroalkyl group having 1 to 20 carbon atoms (such as, for example, (C ₇ H ₁₅ SO ₃ −)
—, (C ₈ H ₁₇ SO ₃ —) —) and a C _m F _{2m + 1} SO ₂ N (R ₁ ) R ₂ — group having 1 to 20 carbon atoms, wherein R ₁ is hydrogen,
An alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkylcarboxyl group having 1 to 20 carbon atoms or an aryl group, wherein R ₂ is an alkylene group having 1 to 20 carbon atoms, And n represents an integer of 1 to 20. For example, C ₇ F ₁₅ SO _{2
N (C 2 H 5) CH} 2 -, C 8 F 17 SO 2 N (CH 2 COO
H) C ₃ H ₆ —), each of which may further have a substituent. A is a group having an alkylene oxide group such as an ethylene oxide group, a propylene oxide group, or an isopropylene oxide group, and may have a substituent such as an amino group at a terminal. Specific examples of the compound represented by the general formula (1) are shown below, but it should not be construed that the invention is limited thereto.

[0022] _{F-1 C 12 F 25 (} CH 2 CH 2 O) 24 C 12 F 25 F-2 C 8 F 17 (CH 2 CH 2 O) 8 C 8 F 17 F-3 C 8 F 17 (CH ₂ CH ₂ O) ₁₂ C ₈ F ₁₇ F-4 C ₇ F ₁₅ (CH ₂ CH ₂ O) ₁₀ C ₇ F ₁₅ F-5 C ₁₂ F ₂₅ (CH ₂ CH ₂ O) ₁₀ C ₁₂ F ₂₅ F- _{6 C 8 F 17 (CH 2} CH 2 O) 17 C 8 F 17 F-7 C 7 F 15 SO 3 - · NH 3 + (CH 2 CH 2 O) 12 N
^{_{H 3 + · SO 3 - C}} 7 F 15 F-8 C 7 F 15 SO 2 N (C 2 H 5) CH 2 (CH 2 CH 2
O) ₁₂ CH ₂ (CH ₃ ) NO ₂ SC ₇ F _{15 The} compound represented by the general formula (1) may be used in combination with another fluorine-based surfactant. Preferred compounds that can be used in combination include those described in JP-A-2-82247, page (4), upper left column.
(8) Compounds (1) to (81) described in the upper left column of the page.

The amount of the compound represented by the general formula (1) of the present invention is 1 × 10 ^-6 to 1 / m ^{2 of the} photothermographic material.
A range of × 10 ^-2 mol is preferred. General formula (1) of the present invention
The compound represented by may be dissolved in water or an organic solvent and added to the coating solution of the constituent layer of the photothermographic material, or may be added as a fine particle solid dispersion, or after coating the coating solution. A solution or a solid dispersion of fine particles may be sprayed.

The compound represented by the general formula (1) of the present invention is used in a layer on the opposite side of the image forming layer, for example, in a subbing layer on a support, a backing layer containing an antihalation dye or a backing protective layer. It is preferably contained in a species, and is preferably contained in at least the outermost layer on the side opposite to the image forming layer.

In another embodiment, it is preferable that at least one kind of compound is contained in a layer on the image forming layer side, for example, an undercoat layer on the support, an image forming layer, a protective layer or an intermediate layer thereof. It is preferred that it is contained at least in the outermost layer on the image forming layer side.

In the most preferred embodiment of the present invention, the compound represented by the general formula (1) is contained in both the layer on the image forming layer side and the layer on the side opposite to the image forming layer. It is preferably contained in the outermost layer on the opposite side of the image forming layer and the outermost layer on the image forming layer side.

<Image Forming Layer> The photothermographic material of the present invention has at least one image forming layer on a support.
Although only the image forming layer may be formed on the support, it is preferable to form at least one non-image forming layer on the image forming layer. In order to control the amount or wavelength distribution of light passing through the image forming layer, a filter dye layer may be formed on the same side as the image forming layer and / or an antihalation dye layer, a so-called backing layer, may be formed on the opposite side. The formation layer may contain a dye or a pigment. As the dye to be used, any compound may be used as long as it has a desired absorption in a desired wavelength range, and for example, JP-A-59-6481.
JP-A-59-182436, U.S. Pat.
1,263, U.S. Pat. No. 4,594,312, EP 533008, EP 652473,
JP-A-2-216140, JP-A-4-348339
JP-A-7-191432, JP-A-7-30189
Compounds described in No. 0 and the like are preferably used.

These non-image forming layers preferably contain the binder or matting agent described above, and may further contain a slip agent such as a polysiloxane compound, wax or liquid paraffin.

The image forming layer may be a plurality of layers, or the image forming layer may be a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / high-sensitivity layer for adjusting the gradation.

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 photosensitive silver halide, a reducing agent and, if necessary, silver. It is preferable that the photothermographic material contains a color toning agent which suppresses the color tone of the present invention in a state of being usually dispersed in an (organic) binder matrix. The photothermographic material of the present invention is stable at room temperature, but is exposed to a high temperature (for example, 80 ° C. to 14 ° C.).
(0 ° 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 proceeds without supplying a processing liquid such as water from the outside.

(Organic Silver Salt) In the present invention, the organic silver salt is a reducible silver source, and a silver salt of an organic acid and a heteroorganic acid containing a reducible silver ion source, especially a long chain (10 to 10) 3
An aliphatic carboxylic acid having 0, preferably 15 to 25 carbon atoms) and a nitrogen-containing heterocyclic ring are preferred. When the ligand is 4.0
Organic or inorganic silver salt complexes having a total stability constant for silver ions of １10.0 are also useful. Examples of suitable silver salts are
Research Disclosure (hereinafter RD)
17029 and 29996, and include the following: salts of organic acids (eg, gallic acid,
Salts of oxalic acid, behenic acid, arachidic acid, stearic acid, palmitic acid, lauric acid, etc.); carboxyalkylthiourea salts of silver (eg, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) −3,
3-dimethylthiourea, etc.); silver complexes of polymer reaction products of aldehydes with hydroxy-substituted aromatic carboxylic acids (eg, aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.), hydroxy-substituted acids (eg, salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodisalicylic acid)), silver salts or complexes of thioenes (for example, 3- (2-carboxyethyl) -4-hydroxymethyl-4- (thiazoline-2-)
Thioene and 3-carboxymethyl-4-thiazoline-2-thioene), imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole, 3-amino-5-benzylthio-1,2,4-triazole And a complex or salt of a nitrogen acid and silver selected from benzotriazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides. Of these, preferred silver sources are silver behenate, arachidic acid and / or stearic acid.

The organic silver salt compound can be obtained by mixing a water-soluble silver compound and a compound which forms a complex with silver, and includes a normal mixing method, a reverse mixing method, a simultaneous mixing method, and a method disclosed in JP-A-9-12764.
A controlled double jet method as described in No. 3 is preferably used. For example, an organic acid alkali metal salt soap (eg, sodium hydroxide, potassium hydroxide, etc.)
Sodium behenate, sodium arachidate, etc.)
The soap and silver nitrate are added to produce organic silver salt crystals. At that time, silver halide grains may be mixed.

In the present invention, the organic silver salt has an average particle size of 2 μm.
m or less and monodisperse. The average particle size of the organic silver salt refers to the diameter of a sphere equivalent to the volume of the organic silver salt particles when the particles of the organic silver salt are, for example, spherical, rod-shaped, or tabular particles. The average particle size is preferably 0.05 μm to 1.5 μm, particularly 0.05 μm
~ 1.0 µm is preferred. The monodispersion has the same meaning as in the case of silver halide, and preferably has a monodispersity of 1 to 30. Further, in the organic silver salt of the present invention, it is preferable that 60% or more of the total organic silver salt is tabular grains. In the present invention, the tabular grains mean those having an aspect ratio (abbreviated as AR) of 3 or more, which is a ratio between the average particle diameter and the thickness, that is, the so-called following formula.

AR = average particle size (μm) / thickness (μm) In order to make the organic silver salt into these shapes, the organic silver crystal is dispersed and pulverized together with a binder, a surfactant and the like by a ball mill or the like. can get. Within this range, a photosensitive material having a high density and excellent image storability can be obtained.

In the present invention, in order to prevent devitrification of the light-sensitive material, the total amount of silver halide and organic silver salt is preferably from 0.5 g to 2.2 g per m ² in terms of silver. preferable. With this range, a high-contrast image can be obtained. The amount of silver halide relative to the total amount of silver is 5% by weight.
0% or less, preferably 25% or less, more preferably 0.1% or less.
It is between 1% and 15%.

(Reducing Agent) The photothermographic material of the present invention preferably contains a reducing agent. Examples of suitable reducing agents are described in U.S. Patent Nos. 3,770,448 and 3,773.
No. 3,512, No. 3,593,863, and RD1
7029 and 29996, and include the following.

Aminohydroxycycloalkenonone compounds (eg, 2-hydroxypiperidino-2-cyclohexenone); aminoreductones esters (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents An N-hydroxyurea derivative (for example, Np-methylphenyl-N
Hydrazones of aldehydes or ketones (e.g. anthracene aldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (e.g.
Hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5-dihydroxy-phenyl) methylsulfone); sulfhydroxamic acids (eg, benzenesulfhydroxamic acid); sulfonamidoanilines (eg, 4- (N- Methanesulfonamido) aniline); 2-tetrazolylthiohydroquinones (eg, 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (eg, 1,2,3,4-tetrahydro) Amide oximes; azines (for example, a combination of an aliphatic carboxylic acid arylhydrazide and ascorbic acid); a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine; hydroxanoic acids Combinations of azines and sulfonamide phenols; α-cyanophenylacetic acid derivatives; combinations of bis-β-naphthol and 1,3-dihydroxybenzene derivatives; 5-pyrazolones; sulfonamide phenol reducing agents; 2-phenylindane-1 ,
Chromanes; 1,4-dihydropyridines (for example, 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine); bisphenols (for example, bis (2-hydroxy-3- t-butyl-5
-Methylphenyl) methane, bis (6-hydroxy-m
-Tri) mesitol, 2,2-bis (4-hydroxy-3-methylphenyl) propane,
4,5-ethylidene-bis (2-t-butyl-6-methyl) phenol), ultraviolet-sensitive ascorbic acid derivatives and 3-pyrazolidones. Among them, particularly preferred reducing agents are hindered phenols. Examples of the hindered phenols include compounds represented by the following general formula (A).

[0038]

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In the formula, R is a hydrogen atom or a group having 1 to 1 carbon atoms.
10 alkyl group (e.g., -C ₄ H _9, 2,4,4-trimethyl pentyl) represents, R 'and R "is an alkyl group having 1 to 5 carbon atoms (e.g., methyl, ethyl, t- butyl ).

Specific examples of the compound represented by formula (A) are shown below. However, the present invention is not limited to the following compounds.

[0041]

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[0042]

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The amount of the reducing agent including the compound represented by formula (A) is preferably 1 × 1 per mol of silver.
It is from 0 ^-2 to 10 mol, especially from 1 x 10 ^{-2 to} 1.5 mol.

(Binder) Binders suitable for the photothermographic material of the present invention are transparent or translucent, generally colorless, and include natural polymer synthetic resins, polymers and copolymers,
Other film forming media, for example: gelatin, gum arabic, poly (vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl) (Methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-
Butadiene), poly (vinyl acetal) s (for example,
Poly (vinyl formal) and poly (vinyl butyral)), poly (ester) s, poly (urethane) s, phenoxy resins, poly (vinylidene chloride), poly (epoxides), poly (carbonates), poly (vinyl acetate) ), Cellulose esters and poly (amides). Although it may be hydrophilic or hydrophobic, in the present invention, it is preferable to use a hydrophobic transparent binder in order to reduce fog after thermal development. Preferred binders include poly (vinyl butyral), cellulose acetate, cellulose acetate butyrate, polyester, polycarbonate, polyacrylic acid, polyurethane and the like. Among them, polyvinyl butyral, cellulose acetate, cellulose acetate butyrate, and polyester are particularly preferably used.

(Photosensitive Silver Halide) The photosensitive silver halide (hereinafter simply referred to as silver halide) in the present invention functions as an optical sensor. In the present invention, in order to suppress white turbidity after image formation and to obtain good image quality, it is preferable that the average grain size of silver halide is small, and the average grain size is 0.1 μm or less, more preferably 0.01 μm to 0.1 μm, especially 0.02 μm
m to 0.08 μm is preferred. The term "grain size" as used herein refers to the length of a ridge of a silver halide grain when the silver halide grain is a cubic or octahedral so-called normal crystal. In the case of non-normal crystals, for example, in the case of spherical, rod-shaped or tabular grains, it refers to the diameter of a sphere equivalent to the volume of silver halide grains. The silver halide is preferably monodispersed. The monodispersion here is
The monodispersity determined by the following formula is 40% or less. It is more preferably at most 30%, particularly preferably 0.1%
The particles are at least 20% or less.

Monodispersity (%) = (standard deviation of particle size) /
(Average value of grain size) × 100 In the present invention, the silver halide grains have an average grain size of 0.1.
μm or less and more preferably monodisperse particles,
By setting it in this range, the granularity of the image is also improved.

The shape of the silver halide grains is not particularly limited, but it is preferable that the ratio occupied by the Miller index [100] plane is high, and this ratio is 50% or more, and more preferably 7%.
It is preferably at least 0%, particularly preferably at least 80%. The ratio of the Miller index [100] plane is determined by taking into account the dependence of the adsorption of the sensitizing dye on the [111] plane and the [100] plane. Tani, J .; Imaging Sci. , 29,
165 (1985).

Another preferred form of silver halide is tabular grains. The term “tabular grains” as used herein means that the square root of the projected area is defined as a grain size r μm and the thickness in the vertical direction is h.
The aspect ratio = r / h in the case of μm is 3 or more. Among them, the aspect ratio is preferably 3 or more and 5 or more.
0 or less. The particle size is preferably 0.1 μm or less, and more preferably 0.01 μm to 0.08 μm.
These are disclosed in U.S. Patent Nos. 5,264,337 and 5,31.
No. 4,798, 5,320,958, and the like, the desired tabular grains can be easily obtained. When these tabular grains are used in the present invention, the sharpness of an image is further improved.

The halogen composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide and silver iodide. The photographic emulsion used in the present invention is P.I. Chimie et by Glafkids
Physique Photographique (P
aul Montel, 1967); F. D
Photographic Emuls by uffin
ion Chemistry (The Focal P
Res., 1966); L. Zelikman
Making and Coating by et al
Photographic Emulsion (Th
e Focal Press, 1964) and the like. That is, any of an acidic method, a neutral method, an ammonia method, etc. may be used.
Any of a one-side mixing method, a simultaneous mixing method, a combination thereof and the like may be used. The silver halide may be added to the image forming layer by any method, in which case the silver halide is arranged close to the reducible silver source. Further, the silver halide may be prepared by converting a part or all of the silver in the organic acid silver by the reaction of the organic acid silver and the halogen ion into silver halide, or may be prepared by preparing silver halide in advance. In advance, this may be added to a solution for preparing an organic silver salt, or a combination of these methods is possible, but the latter is preferred. Generally, the silver halide is preferably contained in an amount of 0.75 to 30% by weight based on the organic silver salt.

The silver halide used in the present invention preferably contains metal ions belonging to groups 6 to 11 of the periodic table. As the above metals, W, Fe, Co,
Ni, Cu, Ru, Rh, Pd, Re, Os, Ir, P
t and Au are preferred.

These metal ions can be introduced into silver halide in the form of a metal complex or a metal complex ion. As these metal complexes or metal complex ions, six-coordinate metal complexes represented by the following general formula are preferable.

In the formula [ML ₆ ] ^m , M is a transition metal selected from elements of Groups 6 to 11 of the periodic table, L is a ligand, and m is 0,-, 2-, 3- or 4- Represents Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate,
Terrocyanate, each ligand of azide and aquo, nitrosyl, thionitrosyl and the like, preferably aquo,
And nitrosyl and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands. L may be the same or different.

Particularly preferred examples of M are rhodium (Rh), ruthenium (Ru), rhenium (Re), iridium (Ir) and osmium (Os).

Specific examples of transition metal complex ions are shown below, but the present invention is not limited to these.

[0055] 1: [RhCl _6] ^3- 2: [RuCl _6] ^3- 3: [ReCl _6] ^3- 4: [RuBr _6] ^3- 5: [OsCl _6] ^3- 6: [IrCl _6] ^{4 -} 7: [Ru (NO) Cl _5] ^2- 8: [RuBr ₄ (H ₂ O)] ^2- 9: _{[Ru (NO) (H 2 O} ) Cl 4 ] ^- 10: [RhCl ₅ (H ₂ O)] ^2- 11: [Re (NO) Cl _5] ^2- 12: [Re (NO) CN _5] ^2- 13: [Re (NO) ClCN _4] ^2- 14: [Rh (NO) ₂ Cl _4] ^- 15: _{[Rh (NO) (H 2 O} ) Cl 4 ] ^- 16: [Ru (NO) CN _5] ^2- 17: [Fe (CN) _6] ^3- 18: [Rh (NS) Cl _5] ^2- 19: [Os (NO) Cl _5] ^2- 20: [Cr (NO) Cl _5] ^2- 21: [Re (NO) Cl _5] ^- 22: [Os (NS) Cl ₄ (TeCN )] ^2-23 : [Ru (NS) Cl _5] ^2- 24: _{[Re (NS) Cl 4 (SeCN} ) ] ^2- 25: [Os (NS) Cl (SCN) 4 ] ^2- 26: [Ir (NO) Cl _5] ^2-27 : [Ir (NS) Cl ₅ ] ^2- These metal ions, metal complexes or metal complex ions may be of one type, or two or more of the same and different metals may be used in combination. The content of these metal ions, metal complexes or metal 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.

The compounds providing these metals are preferably added during silver halide grain formation and incorporated into silver halide grains. Preparation of silver halide grains, that is, nucleation, growth, physical ripening, and chemical ripening are carried out. Although it may be added at any stage before and after sensitization, it is particularly preferable to add at the stage of nucleation, growth and physical ripening, more preferably at the stage of nucleation and growth, and most preferably. It is added at the stage of nucleation.

In the addition, the compound may be added in several divided portions, may be uniformly contained in the silver halide grains, or may be added to silver halide grains.
-306236, 3-167545, 4-76
No. 534, No. 6-110146, No. 5-273683
As described in Japanese Patent Application Laid-Open No. H10-284, etc., the particles can be contained in the particles with a distribution. Preferably, a distribution can be provided inside the particles.

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.

At the time of addition to the particle surface, a required amount of an aqueous solution of a metal compound may be charged into the reaction vessel immediately after the formation of the particles, during or during physical ripening, or at the time of chemical ripening.

The photosensitive silver halide grains can be desalted by washing with water by a method known in the art such as a noodle method or a flocculation method. Is also good.

The photosensitive silver halide grains in the present invention are preferably chemically sensitized. Preferred chemical sensitization methods are sulfur sensitization, selenium sensitization, tellurium sensitization, noble metal sensitization such as gold compounds, platinum, palladium, and iridium compounds, and reduction sensitization as well known in the art. Sensitization can be used. Known compounds can be used as compounds preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method.
Compounds described in No. 8768 and the like can be used.
Compounds preferably used in the noble metal sensitization method are described, for example, in chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, and US Pat. No. 2,448,060 and British Patent 618,061. The compounds described above can be preferably used. As specific compounds of the reduction sensitization method, in addition to ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like can be used. . Further, reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ions during grain formation.

(Matting Agent) In the present invention, a matting agent is preferably contained on the image forming layer side, and a matting agent is provided on the surface of the photosensitive material in order to prevent the image after thermal development from being damaged. Preferably, the matting agent is contained in a weight ratio of 0.5 to 30% with respect to all binders on the image forming layer side. When a non-image forming layer is provided on the surface opposite to the image forming layer with the support interposed therebetween, it is preferred that at least one layer on the non-image forming layer side contains a matting agent, and the slip property of the photosensitive material is improved. It is also preferable to provide a matting agent on the surface of the light-sensitive material for preventing the adhesion of fingerprints and fingerprints. It is preferred to contain.

The material of the matting agent used in the present invention 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. An earth metal or a carbonate such as cadmium or zinc can be used as a matting agent. As organic matter,
Starch described in U.S. Pat. No. 2,322,037, Belgian Patent No. 625,451 and British Patent No. 981,19
No. 8 and the like, and starch derivatives described in JP-B-44-3643.
No. 33, Swiss Patent No. 33
No. 0,158, polystyrene or polymethacrylate; U.S. Pat. No. 3,079,257; polyacrylonitrile; U.S. Pat. No. 3,022,16.
An organic matting agent such as polycarbonate described in No. 9 or the like can be used.

The shape of the matting agent may be either regular or irregular, but is preferably regular and spherical. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. In the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere.

The matting agent used in the present invention preferably has an average particle size of 0.5 μm to 10 μm, more preferably 1.0 μm to 8.0 μm. The matting agent has a coefficient of variation of the particle size distribution of preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the variation coefficient of the particle size distribution is a value represented by the following equation.

(Standard deviation of particle size) / (Average value of particle size) ×
100 The matting agent according to the present invention can be contained in any constituent layer. However, in order to achieve the object of the present invention, the matting agent is preferably a constituent layer other than the image forming layer, more preferably from the viewpoint of the support. The outermost layer.

The method of adding the matting agent according to the present invention may be a method of dispersing in a coating solution in advance and applying the solution.
A method of spraying a matting agent after the application liquid is applied and before the drying is completed may be used. When a plurality of types of matting agents are added, both methods may be used in combination.

(Color Toning Agent) Examples of suitable color toning agents used in the present invention are disclosed in RD17029 and include the following.

Imides (for example, phthalimide); cyclic imides, pyrazolin-5-ones and quinazolinones (for example, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2 , 4-thiazolidinedione); naphthalimides (eg, N-hydroxy-1,8-naphthalimide); cobalt complexes (eg, hexamine trifluoroacetate of cobalt), mercaptans (eg, 3
-Mercapto-1,2,4-triazole); N- (aminomethyl) aryldicarboximides (for example,
N- (dimethylaminomethyl) phthalimide); blocked pyrazoles, isothiuronium (isoth
uronium) derivatives and certain photobleaching combinations (eg, N, N'-hexamethylene (1-carbamoyl-3,5-dimethylpyrazole), 1,8-
A combination of (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) benzothiazole; a merocyanine dye (e.g., 3-ethyl-5-((3-ethyl -2-benzothiazolinylidene (benzothiazolinylidene))-1-methylethylidene) -2-thio-2,4
-Oxazolidinedione); phthalazinone, a phthalazinone derivative or a metal salt of these derivatives (for example, 4-
(1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethyloxyphthalazinone, and 2,3
-Dihydro-1,4-phthalazinedione); a combination of phthalazinone and a sulfinic acid derivative (for example, 6-chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); phthalazine + phthalate Acid combinations; phthalazine (including phthalazine adducts) and maleic anhydride,
And phthalic acid, 2,3-naphthalenedicarboxylic acid or o
At least one selected from phenylene acid derivatives and anhydrides thereof (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride);
Quinazolinediones, benzoxazines, naloxazine derivatives; benzoxazine-2,4-diones (eg, 1,3-benzoxazine-2,4-dione); pyrimidines and asymmetric triazines (E.g., 2,4-dihydroxypyrimidine) and tetraazapentalene derivatives (e.g., 3,
6-dimercapto-1,4-diphenyl-1H, 4H-
2,3a, 5,6a-tetraazapentalene). Of these, phthalazone or phthalazine is preferred as a color tone agent.

(Supersensitizer) In the present invention, a mercapto compound, a disulfide, and the like are used in order to suppress or accelerate development to control development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. Compounds and thione compounds can be contained.

When a mercapto compound is used in the present invention, it may be of any structure,
Those represented by -SS-Ar are preferred.

In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or a condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthymidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole,
Benzoselenazole, benzotellazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogens (eg, Br and Cl), hydroxy, amino,
Carboxy, alkyl (eg, one or more carbon atoms,
Preferably those having 1 to 4 carbon atoms) and alkoxy (for example one or more carbon atoms, preferably 1 to 4 carbon atoms).
Which have four carbon atoms). Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzothiazole, 3-mercapto-1,2,4-triazole, -Mercaptoquinoline, 8-mercaptopurine, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-hydroxy-2-mercaptopyrimidine,
-Mercapto-4-phenyloxazole and the like, but the present invention is not limited thereto.

(Anti-fogging agent) The photothermographic material of the present invention may contain an anti-fogging agent. Mercury compounds known as effective antifoggants, for example, in US Pat. No. 3,589,903, are environmentally unfavorable. Therefore, non-mercury antifoggants have been studied for a long time. Non-mercury antifoggants include, for example, U.S. Pat.
Preferred are antifoggants such as those disclosed in 546,075 and 4,452,885 and JP-A-59-57234.

In the present invention, in order to further improve the density fluctuation in thermography, an oxidizing agent for reducing fog after development is used. Such oxidizing agents are preferably, for example, those described in JP-A-50-119624 and JP-A-50-12.
No. 0328, No. 51-121332, No. 54-580
No. 22, 56-70543, 56-99335
No., 59-90842, 61-129,624,
62-129845, JP-A-6-208191,
No. 7-5621, No. 7-2781, No. 8-1580
9, U.S. Patent Nos. 5,340,712 and 5,36
Nos. 9,000 and 5,464,737; U.S. Pat. Nos. 3,874,946; 4,756,999; 5,340,712; and EP 605981 A1.
Nos. 622666A1, 631176A1, JP-B-54-165, JP-A-7-2781, and U.S. Pat. Nos. 4,180,665 and 4,442,202. However, a polyhalogen compound represented by the following general formula (2) is preferable.

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In the formula, A represents an aliphatic group, an aromatic or heterocyclic group, and X ₁ , X ₂ and X ₃ each represent a hydrogen atom or an electron-withdrawing group, which may be the same or different. Y is 2
Represents a valent linking group.

Next, the compound represented by formula (2) will be described in detail.

X ₁ , X ₂ , and X _{3 each} represent a hydrogen atom or an electron-withdrawing group. The electron-withdrawing groups represented by X ₁ , X ₂ , and X ₃ preferably have a σp value of 0.01. It is the above substituent, more preferably 0.1 or more substituent. Regarding the Hammett's substituent constant, Journal of M
edininal Chemistry, 1973, V
ol. 16, No. 11, 1207 to 1216 can be referred to.

Examples of the electron-withdrawing group include a halogen atom (a fluorine atom (σp value: 0.06) and a chlorine atom (σp
Value: 0.23), bromine atom (σp value: 0.23), iodine atom (σp value: 0.18), trihalomethyl group (tribromomethyl (σp value: 0.29), trichloromethyl (σp value) Value: 0.33), trifluoromethyl (σp
Value: 0.54)), cyano group (σp value: 0.66), nitro group (σp value: 0.78), aliphatic / aryl or heterocyclic sulfonyl group (for example, methanesulfonyl (σ
p value: 0.72)), aliphatic / aryl or heterocyclic acyl group (eg, acetyl (σp value: 0.50), benzoyl (σp value: 0.43)), alkynyl group (eg, C ₃ H) ₃ (σp value: 0.09)), aliphatic / aryl or heterocyclic oxycarbonyl group (for example, methoxycarbonyl (σp value: 0.45), phenoxycarbonyl (σp value: 0.45)), carbamoyl group ( σp value:
0.36), a sulfamoyl group (σp value: 0.57) and the like.

X ₁ , X ₂ and X ₃ are preferably an electron-withdrawing group, and particularly preferably a halogen atom. Among the halogen atoms, a chlorine atom, a bromine atom and an iodine atom are preferred, a chlorine atom and a bromine atom are more preferred, and a bromine atom is particularly preferred.

Y represents a divalent linking group, specifically, -S
O ₂ —, —SO—, —CO—, —N (R ₁₁ ) —SO ₂ —,
_{-N (R 11) -CO -,} - N (R 11) -COO -, - C
OCO-, -COO-, -OCO-, -OCOO-,-
SCO—, —SCOO—, —C (Z ₁ ) (Z ₂ ) —, an alkylene, an arylene, a divalent heterocyclic ring, and a divalent substituent formed by any combination thereof. R ₁₁ represents a hydrogen atom or an alkyl group, preferably a hydrogen atom. Z ₁ and Z ₂ represent a hydrogen atom or an electron-withdrawing group, but are not a hydrogen atom at the same time. Preferably, the Hammett's substituent constant σp value is 0.0
It is at least one substituent, more preferably at least 0.1 substituent. Preferred examples of the electron-withdrawing group for Z ₁ and Z ₂ are the same as those described above for X ₁ , X ₂ and X ₃ .

Z ₁ and Z ₂ are preferably a halogen atom, a cyano group or a nitro group. Among the halogen atoms, a chlorine atom, a bromine atom and an iodine atom are preferred, a chlorine atom and a bromine atom are more preferred, and a bromine atom is particularly preferred. Y is preferably -SO
_2- , -SO-, -CO-, more preferably -S
Represents O ₂ —.

The aliphatic group represented by A is a straight-chain, branched or cyclic alkyl group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20, more preferably 1 to 12; Ethyl, iso-propyl, tert-butyl, n-octyl, n-decyl, cyclopropyl, cyclopentyl, cyclohexyl, etc., and an alkenyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms, furthermore Preferably it is 2-12, for example, vinyl, allyl, 2-butenyl, 3-pentenyl etc.), alkynyl group (preferably having 2-3 carbon atoms)
0, more preferably 2 to 20, even more preferably 2 to 12
And for example, propargyl, 3-pentenyl and the like. ), And may have a substituent. Examples of the substituent include a carboxy group, an acyl group, an acylamino group, a sulfonylamino group, a carbamoyl group, a sulfamoyl group, an oxycarbonylamino group, and a ureido group. The aliphatic hydrocarbon group is preferably an alkyl group, and more preferably a chain alkyl group.

The aromatic group represented by A is preferably an aryl group, and the aryl group is preferably a monocyclic or bicyclic aryl group having 6 to 30 carbon atoms (eg, phenyl, naphthyl, etc.) More preferably, it has 6 to 2 carbon atoms.
0 phenyl group, more preferably 6 to 12 phenyl groups. The aryl group may have a substituent, and examples of the substituent include a carboxy group, an acyl group, an acylamino group, a sulfonylamino group, a carbamoyl group, a sulfamoyl group, an oxycarbonylamino group, and a ureido group. The heterocyclic group represented by Q is a 3- to 10-membered saturated or unsaturated heterocyclic ring containing at least one of N, O and S atoms, which may be a single ring, And a fused ring may be formed.

The heterocyclic group represented by A is preferably a 5- or 6-membered aromatic heterocyclic group, more preferably a 5- or 6-membered aromatic heterocyclic group containing a nitrogen atom, and further preferably Is a 5- or 6-membered aromatic heterocyclic group containing 1 or 2 nitrogen atoms. Specific examples of the heterocycle include, for example, pyrrolidine, piperidine, piperazine, morpholine, thiophene, furan, pyrrole, imidazole, pyrazole, pyridine, pyrazine, pyridazine,
Triazole, triazine, indole, indazole, purine, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, thiazole,
Oxazole, benzimidazole, benzoxazole, benzothiazole and the like can be mentioned. Preferably as a heterocycle, thiophene, furan, pyrrole, imidazole, pyrazole, pyridine, pyrazine, pyridazine,
Triazole, triazine, indole, indazole, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline,
Cinnoline, pteridine, tetrazole, thiazole,
Oxazole, benzimidazole, benzoxazole, benzothiazole and indolenine, more preferably triazine, quinoline, thiadiazole, benzthiazole and oxadiazole, particularly preferably pyridine, quinoline, thiadiazole and oxadiazole. A is preferably an aromatic nitrogen-containing heterocyclic group.

Among the above polyhalogen compounds, compounds represented by the general formula (2-a) are more preferably used.

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In the general formula (2-a), A represents an aliphatic group, an aromatic or a heterocyclic group. X ₁ , X ₂ and X ₃ are a hydrogen atom or a halogen atom, and may be the same or different. A, X ₁ , X ₂ and X ₃ have the same meanings as those in formula (2), and the preferred ranges are also the same.

The following are specific examples of the polyhalogen compound used in the present invention, but are not limited thereto.

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In the present invention, the oxidizing agent contains 10 mg / m ²
３3 g / m ^2, preferably 50 mg / m ² 〜
1 g / m ² is more preferred.

In the present invention, the oxidizing agent may be added by any method such as a solution, a powder, and a dispersion of solid fine particles, and it is particularly preferable that the oxidizing agent is dispersed in the image forming layer. The dispersion of the solid fine particles is carried out by a known fine means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). At the time of dispersion, a dispersion aid may be used. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent and a color tone agent.

In addition to the above-mentioned oxidizing agents, suitable antifoggants include compounds such as those disclosed in US Pat. Nos. 3,874,946 and 4,756,999; -288328 paragraph number [0030] ~
Compound described in [0036], JP-A-9-90
No. 550, compounds described in paragraphs [0062] to [0063], U.S. Pat. No. 5,028,523 and British Patent Application Nos. 92221383.4 and 9300.
Compounds disclosed in Nos. 147.7 and 9311790.1 are preferably used.

(Other Additives) The photothermographic material of the present invention includes, for example, JP-A-63-159814 and JP-A-60-15941.
140335, 63-231437, 63-2
No. 59651, No. 63-304242, No. 63-15
No. 245, U.S. Pat. Nos. 4,639,414,
Sensitizing dyes described in 740,455, 4,741,966, 4,751,175, and 4,835,096 can be used. Useful sensitizing dyes for use in the present invention are described, for example, in RD17643 IV-A (197).
December 2008 p. 23), Item 1831X (19)
August 1978 p. 437) or in the literature cited. 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, JP-A-9-34078 and JP-A-9-5
Compounds described in Nos. 4409 and 9-80679 are preferably used.

In order to protect the surface of the light-sensitive material and prevent abrasion, a non-image-forming layer may be provided outside the image-forming layer. The binder used in these non-image forming layers may be the same or different from the binder used in the image forming layer.

In the present invention, in order to increase the speed of thermal development, the amount of the binder in the image forming layer is 1.5 to 10 g / m 2.
It is preferably ² . More preferably, 1.7 to 8 g
/ M ² . If it is less than 1.5 g / m ² , the density of the unexposed portion will increase significantly and may not be usable.

Various additives may be added to any of the image forming layer, the non-image forming layer, and other forming layers. The photothermographic material of the present invention may contain, for example, a surfactant, an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, and a coating aid. These additives and the other additives mentioned above are referred to as RD17029 (pp. 9-15, June 1978)
Can be preferably used.

(Support) The support used in the present invention is a plastic film (for example, polyethylene terephthalate (PET),
Polycarbonate, polyimide, nylon, cellulose triacetate, polyethylene naphthalate) are preferred. The thickness of the support is 50 to 300 μm
Degree, preferably 70 to 180 μm. A heat-treated plastic support can also be used. The plastics to be employed include the above-mentioned plastics. The heat treatment of the support means that after forming these supports and before the image forming layer is coated, at a temperature higher than the glass transition point of the support by 30 ° C. or more, preferably at a temperature higher by 35 ° C. or more, More preferably, heating is performed at a temperature higher than 40 ° C. However, the effect of the present invention cannot be obtained by heating at a temperature exceeding the melting point of the support.

The method of forming a support and the method of producing an undercoat according to the present invention may be a known method, but preferably is a method described in paragraphs [0030] to [0] of JP-A-9-50094.
070].

In the present invention, a conductive compound such as a metal oxide and / or a conductive polymer can be included in the constituent layer in order to improve the chargeability. These may be contained in any of the layers, but are preferably contained in an undercoat layer, a backing layer, a layer between the image forming layer and the undercoat, and the like. In the present invention, US Pat. No. 5,244,773 column 1
The conductive compounds described in 4 to 20 are preferably used.

[0107]

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

Example 1 <Heat-Developable Photosensitive Material> (Preparation of Subbed Photographic Support) A PET-subbed photosupport was prepared as follows. A commercially available biaxially stretched heat-fixed PET film having a thickness of 175 μm and a blue density of 0.18 and having a blue coloration is subjected to a corona discharge treatment of 8 w / m ² · min on both surfaces. a-1 was applied so as to have a dry film thickness of 0.8 μm and dried to form an undercoat layer A-1. It was applied so as to have a thickness of 0.8 μm, and was dried to obtain an antistatic processed undercoat layer B-1.

<< Undercoat Coating Solution a-1 >> Co-weight of butyl acrylate (30% by weight), t-butyl acrylate (20% by weight), styrene (25% by weight), and 2-hydroxyethyl acrylate (25% by weight) Combined latex liquid (solid content 30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Polystyrene fine particles (average particle size 3 μm) 0.05 g Colloidal silica (average particle size) (90 μm) 0.1 g Finished to 1 liter with water << Undercoat coating solution b-1 >> SnO ₂ / Sb (weight ratio of 9/1, average particle size 0.18 μm) Amount to become 200 mg / m ² Butyl acrylate (40 weight) %), Styrene (20% by weight), glycidyl acrylate (40% by weight) copolymer latex liquid (solid content 30%) 270 g (C-1) 0.6 Subsequently finish 1l hexamethylene-1,6-bis (ethyleneurea) 0.8 g Water, 8 on the surface of the undercoat layer A-1 and subbing layer B-1
By applying a corona discharge of w / m ² · min, the undercoating layer A-1 is coated with the undercoating upper layer coating solution a-2 as described below so as to have a dry film thickness of 0.1 μm. On the undercoating layer B-1, the following undercoating upper layer coating solution b-2 was applied so as to have a dry film thickness of 0.8 μm as an undercoating upper layer B-2 having an antistatic function.

<< Coating Solution a-2 for Lower Substrate >> Gelatin 0.4 g / m ² Weight (C-1) 0.2 g (C-2) 0.2 g (C-3) 0.1 g Silica particles ( (Average particle size: 3 μm) 0.1 g Finished to 1 liter with water << Lower pull upper layer coating solution b-2 >> (C-4) 60 g Latex liquid containing (C-5) as a component (solid content: 20%) 80 g Ammonium sulfate 5 g (C-6) 12 g Polyethylene glycol (weight average molecular weight 600) 6 g Finish to 1 liter with water

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(Heat Treatment of Support) In the above-described undercoat drying step of the support, the support was heated at 140 ° C.
Thereafter, it was gradually cooled.

<Preparation of silver halide emulsion A>
7.5 g of inert gelatin and 10 ml of potassium bromide
mg, and adjusted to a temperature of 35 ° C. and a pH of 3.0.
1 mol of silver of an aqueous solution and [Ir (NO) Cl _5] salt per mole silver 1 × 10 ^-6 mol, and rhodium chloride salt comprises sodium chloride and potassium bromide and potassium iodide in a molar ratio of 8/2) 1 × 10 ^-6 mol per 1 mol was added by the controlled double jet method while maintaining the pAg at 7.7. Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7-
Cubic silver iodobromide having an average grain size of 0.06 μm, a monodispersity of 10%, a variation coefficient of the projected diameter area of 8%, and a [100] face ratio of 87% is adjusted by adding tetrazaindene and adjusting the pH to 5 with NaOH. Particles were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, and after desalting, 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and the pAg to 7.5. Furthermore, chloroauric acid, inorganic sulfur, thiourea dioxide and 2,2
Chemical sensitization was performed with 3,4,5,6-pentafluorophenylphosphine selenide to obtain a silver halide emulsion A.

<Preparation of sodium behenate solution> 945
32.4 g of behenic acid and 9.9 of arachidic acid in ml of pure water
g and stearic acid 5.6 g were dissolved at 90 ° C. Next, while stirring at a high speed, a 1.5 M aqueous sodium hydroxide solution 9 was added.
8 ml was added. Next, after adding 0.93 ml of concentrated nitric acid, the mixture was cooled to 55 ° C. and stirred for 30 minutes to obtain a sodium behenate solution.

<Preparation of Preform Emulsion of Sodium Behenate Solution and Silver Halide Emulsion A> 15.1 g of the silver halide emulsion A obtained in the above sodium behenate solution was used.
After the addition, the pH was adjusted to 8.1 with a sodium hydroxide solution, 147 ml of a 1M silver nitrate solution was added over 7 minutes, and the mixture was further stirred for 20 minutes, followed by ultrafiltration to remove water-soluble salts.
The resulting silver behenate was grains having an average grain size of 0.8 μm and a monodispersity of 8%. After the floc of the dispersion was formed, the water was removed, washed with water six times and water was removed, and dried.

<Preparation of Photosensitive Emulsion> Polyvinyl butyral (average molecular weight: 3,000) was added to the obtained preform emulsion.
After slowly adding and mixing 544 g of a methyl ethyl ketone solution (17 wt%) and 107 g of toluene,
Dispersed at psi. After the dispersion, the organic silver particles were observed with an electron micrograph. As a result of measuring the particle size and thickness of 300 organic silver particles, 205 of them were tabular organic silver having an AR of 3 or more. Incidentally, the average particle size was 0.7 μm. When the organic silver particles were similarly observed after coating and drying, the same particles were confirmed.

<Coating Step><< Back Layer Surface Side Coating >> A back layer coating solution having the following composition was
It was applied to the undercoat layer B-2 side of the support by an extrusion coater so as to have a wet film thickness of 30 μm.
Dried in 5 minutes.

(Back Layer Coating Solution 1) Cellulose Acetate Butyrate (10% Methyl Ethyl Ketone Solution) 15 ml / m ² Dye-A 7 mg / m ² Dye-B 7 mg / m ² Matting agent (monodispersity 15%, average particle size) 8 μm monodisperse silica) 30 mg / m ² Compound represented by the general formula (1) C ₉ F ₁₇ —C ₆ H ₄ —SO ₃ Na 10 mg / m ² shown in Table 1.

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<< Coating of Image Forming Layer Surface >> A coating solution of an image forming layer having the following composition and a coating solution of a protective layer thereon are applied to the undercoat layer A-2 side of the support by an extrusion coater at a speed of 20 m / min. Was applied in multiple layers. At that time, the coated silver amount was 2.4 g / m
² and applied. Then, at 55 ° C, 15
A minute drying was performed.

(Coating solution of image forming layer) Photosensitive emulsion (obtained above) 240 g Sensitizing dye (0.1% methanol solution) 1.7 ml Pyridinium bromide perbromide (6% methanol solution) 3 ml Bromide Calcium (0.1% methanol solution) 1.7ml Antifoggant (10% methanol solution) 1.2ml 2-Chlorobenzoylbenzoic acid (12% methanol solution) 9.2ml 2-mercaptobenzimidazole (1% methanol solution) Solution) 11 ml Oxidizing agent (Ex. P-69) 17 ml Developer (20% methanol solution) 29.5 ml Phthalazine 0.6 g 4-methylphthalic acid 0.25 g Tetrachlorophthalic acid 0.2 g (Surface protective layer coating solution) Acetone 5 ml / M ² Methyl ethyl ketone 21 ml / m ² Cellulose acetate butyrate 2.3 g / m ² methanol 7 ml / m ² phthalazine 250 mg / m ² matting agent (monodispersity 10% average particle size 4 μm monodisperse silica) 70 mg / m ² vinylsulfone compound VS-1 35 mg / m ₂ General formula (1 ) C ₉ shown in compound table 1 represented by _{F 17 -C 6 H 4 -SO 3} Na 10mg / m 2 was thus obtained the photothermographic material. This is
1 to 110.

[0123]

Embedded image

<< Exposure and Development Processing >> The photothermographic material prepared above was cut into 25 cm × 30 cm pieces at 23 ° C. and 5 ° C.
After humidifying for 12 hours under the condition of 0% RH, 10 sheets were piled up in a barrier bag impermeable to oxygen and moisture, and heated at 40 ° C. for 3 days as a thermo-era thermometer. It was then exposed through a wedge with a sensitometer having a 810 nm semiconductor laser as an alternative to the imager. And radius 20c
Heat development was performed at 110 ° C. for 15 seconds using an automatic developing machine having a heat drum having a cylindrical diameter of m. At that time, exposure and development were performed in a room conditioned at 23 ° C. and 50% RH.

<< Evaluation >> (Transportability test) Thermal development processing was continuously performed on 100 sheets.
At that time, the number of sheets having a conveyance failure was counted.

(Density Fluctuation after Thermal Development) The photothermographic material exposed and thermally developed as described above was divided into two parts, and one of them was put into a thermo machine at 50 ° C. and 60% for 5 days for evaluation for an era. The density was measured using a densitometer to determine how much the density changed from 2.5 before the thermometer was injected to the thermometer.

(Performance Fluctuation Due to Changes in Thermal Development Processing Conditions) The photothermographic material prepared above was exposed to light, the temperature of the automatic developing machine was lowered to 105 ° C., and development was performed for 15 seconds.
The rate of change based on the sensitivity at 10 ° C. for 15 seconds was expressed as a percentage. The sensitivity here is a relative value of a reciprocal of an exposure amount giving a density of 1.0.

The results of the evaluation are shown in Table 1. The structural formulas of Compounds A to C used in Comparative Examples are shown below.

[0129]

[Table 1]

[0130]

Embedded image

As is clear from Table 1, Sample 1 of the present invention
Nos. 05 to 110 were excellent in that no transport failure occurred in the evaluation of the transportability, and in the evaluation of the density fluctuation after the heat development and the performance fluctuation under the change of the heat development processing conditions, both were very slight fluctuations. It turns out that it has performance.

Example 2 Using the sample prepared in Example 1, the adhesion between the support and the constituent layer on the side opposite to the image forming layer was evaluated by the following method.

<< Evaluation of Adhesive Property >> The photothermographic material prepared in Example 1 was cut into 25 cm × 30 cm and cut at 23 ° C.
After adjusting the humidity for 12 hours under the condition of 0% RH, the surface opposite to the image forming layer is obliquely scratched with a cutter, and Scotch tape (registered trademark) is firmly stuck thereon, and the scotch tape is vigorously peeled off. , The degree of peeling was evaluated by visual evaluation
The rank was evaluated. Those that did not come off at all were assigned a rank of 5, and the number was lowered as the degree of peeling increased. Rank 1 is a state in which the support is completely visible.

The results of the evaluation are shown in Table 2.

[0135]

[Table 2]

As is clear from Table 2, Sample 1 of the present invention
It can be seen that Nos. 05 to 110 did not peel off at all. That is, it can be seen that it has excellent adhesiveness.

[0137]

According to the present invention, when processing a photothermographic material, it is possible to prevent defective conveyance in an automatic developing machine, and when storing the photothermographic material for a long period of time, it is possible to suppress the density fluctuation after the heat development, and furthermore, the sensitivity and the sensitivity are independent of the processing temperature. This has a remarkably excellent effect that fluctuation of fog can be eliminated.

Claims (5)

[Claims] 1. A photothermographic material comprising at least one image forming layer having organic silver particles on a support, and a reducing agent contained in a photographic component layer on the side having the image forming layer. At least one compound represented by the following general formula (1)
A photothermographic material comprising a seed. Formula (1) Rf- (A) _n -Rf ′ wherein Rf and Rf ′ are groups having at least one fluorine-containing aliphatic group, A is a group having at least one alkylene oxide group, and n is 1 or more. Represents an integer of Rf,
Rf 'may be the same or different. Where Rf is C _m F
_2m + 1 SO ₃ ^- when representing a · NH ₃ ⁺ groups Rf and Rf 'are the same. m represents an integer of 1 or more. 2. The method according to claim 1, wherein at least one of the compounds represented by the general formula (1) is contained in at least one of the image forming layer side and the side opposite to the image forming layer. Photothermographic material. 3. The photothermographic material according to claim 1, wherein at least one layer on the side of the image forming layer contains a photosensitive silver halide. 4. The photothermographic material according to claim 1, wherein at least one layer on the image forming layer side contains an oxidizing agent. 5. The photothermographic material according to claim 4, wherein the oxidizing agent is a compound represented by the following general formula (2). Embedded image (Wherein A represents an aliphatic group, an aromatic or heterocyclic group, and X
₁ , X ₂ and X ₃ each represent a hydrogen atom or an electron withdrawing group, and may be the same or different. Y represents a divalent linking group. )