JPH11327078A - Heat developable photographic sensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developable photographic sensitive material which lowers surface resistance (surface electric resistance Ω) after heat development and which has good adhesion performance to a film. SOLUTION: This material contains org. silver salts, photosensitive silver halide particles and a reducing agent on a supporting body, and further it has a protective layer containing (1) electrically conductive metal oxides and oil, (2) electrically conductive metal oxides and polymer latex or (3) electrically conductive metal oxides and compds. expressed by the formula. In the formula, R1 to R8 are independently hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, hydroxy groups or satd. aliphatic monocarboxylic acid groups. Preferably the polymer latex has -30 to 90 deg.C Tg (glass transition temp).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable photographic light-sensitive material, and more particularly, to a black-and-white heat-developable photographic light-sensitive material having an excellent antistatic property after development and a film-coated property.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making and medical treatment, waste liquid caused by wet processing of an image forming material has been a problem in terms of workability. There is a strong demand for weight loss. Therefore, there is a need for a photosensitive material that can be efficiently exposed by a laser image setter or a laser imager and that can form a high-resolution and clear black image.

As such photosensitive materials, for example, US Pat. Nos. 3,152,904 and 3,487,075 and D.C. "Dry Silver Photograph" by Morgan
phy Materials) "(Handbook
of Imaging Materials, Mar
cel Dekker, Inc. 48, 1991)
As described in, for example, a photothermographic material containing an organic silver salt, photosensitive silver halide particles and a reducing agent on a support is known. Thereafter, an image is formed by performing thermal development at 80 to 140 ° C., and therefore, in a transport system for photographing and developing, a large amount of charge is generated due to friction and separation with a roller during transport, and static electricity is generated. Poor transport often occurs due to sticking.

As a countermeasure for this, Japanese Patent Application Laid-Open No. Hei 9-146222 discloses a technique for reducing the surface electric resistance to a desirable level by using a conductive metal oxide.

In general, it is known that a metal oxide is contained in, for example, an undercoat layer provided between a support and a photosensitive layer. It has been difficult to obtain sufficient antistatic performance while maintaining film-forming performance after any heat development.

The present inventors have been conducting research on heat-developable photographic light-sensitive materials, especially on lowering the surface electrical resistivity after heating. However, the inventors have found that a conductive metal oxide is contained in the undercoat layer. In this case, the surface electrical resistivity was not sufficiently reduced while maintaining the performance with a film.

Therefore, it is an object to sufficiently lower the surface electric resistivity without deteriorating the film-forming performance of the photothermographic material. The subject of sufficiently lowering the surface electric resistivity without deteriorating the attaching performance was able to be achieved.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-developable photographic light-sensitive material having a low surface electric resistivity (Ω) after heat development and a good film-forming performance.

[0009]

[Means for Solving the Problems] A heat-developable photographic light-sensitive material comprising an organic silver salt, photosensitive silver halide particles and a reducing agent on a support, and a protective layer containing a conductive metal oxide and oil.

[0010] 2. A heat-developable photographic light-sensitive material comprising an organic silver salt, photosensitive silver halide particles and a reducing agent on a support, and a protective layer containing a conductive metal oxide and a polymer latex.

3. 3. The photothermographic material according to item 2, wherein the polymer latex has a Tg (glass transition temperature) of -30 to 90 ° C.

4. A protective layer containing an organic silver salt, photosensitive silver halide particles and a reducing agent, a conductive metal oxide and a compound represented by the following general formula (1) on a support; Heat developed photographic photosensitive material.

[0013]

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Wherein R _{1 to} R ₈ each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group or a saturated aliphatic monocarboxylic acid group. ] 5. Heat-developable photographic material according to any one of 1 to 4, wherein the conductive metal oxide is SnO _2.

Hereinafter, the present invention will be described in detail.

The silver halide grains used in the present invention preferably have an average grain size of 0.2 μm or less, more preferably 0.01 to 0.17 μm, particularly preferably 0.02 to 0.17 μm.
0.14 μm is preferred.

The term "grain size" as used herein means 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 where the silver halide grains are tabular grains, the diameter refers to a diameter when converted into a circular image having the same area as the projected area of the main surface.

The silver halide grains are preferably monodispersed. Here, the monodispersion means that the degree of monodispersion determined by the following equation is 40 or less. The particle size is more preferably 30 or less, and particularly preferably 0.1 to 20.

Monodispersity = (standard deviation of particle size) / (average value of particle size) × 100 The shape of silver halide grains is cubic, octahedral, tabular, spherical, rod-like, potato-like. In the present invention, cubic grains and tabular grains are particularly preferred. When tabular silver halide grains are used, the average aspect ratio is preferably from 2 to 10.
0, more preferably 3 to 50. These are described in U.S. Pat. Nos. 5,264,337, 5,314,798, and 5,320,958, and can easily obtain desired tabular grains.

Further, grains having rounded corners of silver halide grains can be preferably used. Although the outer surface of the silver halide grains is not particularly limited, the Miller index (1)
The ratio of the (00) plane is preferably high, and this ratio is preferably at least 50%, more preferably at least 70%, particularly preferably at least 80%. The ratio of the Miller index (100) plane is determined by T.M. using the dependence of the adsorption of the sensitizing dye on the (111) and (100) planes. Tani, J .; Imagin
g Sci. , 29, 165 (1985).

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. In the present invention, silver bromide or silver iodobromide can be preferably used.
Particularly preferred is silver iodobromide, and the silver iodide content is 0.1%.
-40 mol% is preferable, and 0.1-20 mol% is more preferable.

The distribution of the halogen composition in the grains may be uniform, the halogen composition may be changed stepwise, or may be changed continuously. A preferred example is silver iodide inside the grains. Silver iodobromide grains having a high content can be used. Preferably, silver halide grains having a core / shell structure can be used.

The photographic emulsion used in the present invention is described in P.I. Gl
Chimie et Physique by Afkids
e Photographique (Paul Mon
tel, 1967); F. By Duffin
Photographic Emulsion Chem
istry (published by The Focal Press, 19
66); L. M by Zelikman et al
aking andCoating Photogra
phi Emulsion (The Focal P
Ress, published in 1964) and the like.

That is, any of an acidic method, a neutral method, an ammonia method and the like may be used, and a method of reacting a soluble silver salt with a soluble halide may be any of a one-side mixing method, a double-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 grains used in the present invention preferably contain a complex of a metal selected from the group consisting of Fe, Co, Ru, Rh, Re, Os and Ir. Two or more complexes may be used in combination. The preferred content is 1 × 10 ^-9 to 1 per mol of silver.
The range of × 10 ^-2 mol is preferred, and 1 × 10 ^-8 to 1 × 10 is preferred.
The range of ^-4 is more preferable.

In the present invention, the transition metal complex is preferably a six-coordinate complex represented by the following general formula.

[ML ₆ ] ^{m In the} formula, M is a transition metal selected from elements of Groups 6 to 8 of the periodic table, L is a bridging ligand, and m is 0, -1, -2 or -3.
Represents Specific examples of the ligand represented by L include halide (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide or aquo. Ligand, nitrosyl, thionitrosyl and the like, preferably aquo, 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.

Rhodium (Rh), ruthenium (Ru), rhenium (Re), osmium (O) are used as transition metals selected from the elements of Groups 6 to 8 of the periodic table represented by M.
Preferred specific examples of s) and iridium (Ir) are shown below.

[0029] 1: [RhCl _6] ^3- 2: [RhCl ₅ (H ₂ O)] ^2- 3: [Rh (NO) ₂ Cl _4] ^- 4: _{[Rh (NO) (H 2 O} ) Cl 4 ] ^- 5: [Rh (NS) Cl _5] ^2- 6: [RuCl _6] ^3- 7: [RuBr _6] ^3- 8: [Ru (NO) Cl _5] ^2- 9: [Ru (NO) ( H ₂ O) Cl _4] ^- 10: [Ru (NS) Cl _5] ^2- 11: [RuBr ₄ (H ₂ O)] ^2- 12: [Ru (NO) CN _5] ^2- 13: [ReCl ₆ ^3- 14: [Re (NO) Cl _5] ^2- 15: [Re (NO) CN _5] ^2- 16: [Re (NO) ClCN _4] ^2- 17: [Re (NO) Cl _5] ^- 18: _{[Re (NS) Cl 4 (SeCN} ) ] ^2- 19: [OsCl _6] ^3- 20: [Os (NO) Cl _5] ^2- 21: _{[Os (NS) Cl 4 (TeCN} ) ] ^2- 22: [Os NS) Cl (SCN) _4] ^2- 23: [IrCl ₅ ^2- 24: [Ir (NO) Cl _5] ^2- chromium, cobalt, for compounds of iron can be preferably used a hexacyano metal complex. Specific examples are shown below.

[0030] 25: [Cr (NO) Cl _5] ^2- 26: [CrCl _6] ^4- 27: [Fe (CN) _6] ^4- 28: [Fe (CN) _6] ^3- 29: [Co ( CN) ₆ ] ^3- A compound that provides an ion or a complex ion of these metals is preferably added during the formation of silver halide grains and incorporated into silver halide grains. Formation, growth, physical ripening, may be added at any stage before and after chemical sensitization, especially nucleation, growth,
It is preferably added at the stage of physical ripening, and more preferably at the stage of nucleation and growth. Most preferably, it is added at the stage of nucleation. In the addition, it may be added in several divided portions, and may be uniformly contained in the silver halide grains.
3, JP-A-2-306236, JP-A-3-167545
Nos. 4-76534, 6-110146, 5
As described in, for example, JP-A-273683, it can be contained in the particles with a distribution. It is preferable to have a distribution inside the particles. These metal compounds may be water or a suitable organic solvent (eg, alcohols,
Ethers, glycols, ketones, esters, amides), and can be added. For example, an aqueous solution of a metal compound powder or a metal compound and NaC
1, a method in which an aqueous solution in which KCl is dissolved together is added to a water-soluble silver salt solution or a water-soluble halide solution during grain formation, or a third method in which the silver salt solution and the halide solution are simultaneously mixed. A method of preparing silver halide grains by a method of simultaneous mixing of three liquids, a method of charging a required amount of an aqueous solution of a metal compound into a reaction vessel during grain formation,
Alternatively, there is a method in which another silver halide grain doped with metal ions or complex ions in advance during the preparation of 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 surface of the particles, 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 during physical ripening, or at the time of chemical ripening.

The photosensitive silver halide grains of the present invention can be desalted by a known desalting method such as a noodle method, flocculation method, ultrafiltration method, and electrodialysis method.

The photosensitive silver halide grains of the present invention are preferably chemically sensitized. Examples of the sensitization method include known methods such as sulfur sensitization, selenium sensitization, tellurium sensitization, noble metal sensitization and reduction sensitization. A sensitization method can be used. These sensitization methods can be used in combination of two or more. For sulfur sensitization, thiosulfates, thiourea compounds, inorganic sulfur and the like can be used. Compounds preferably used for selenium sensitization and tellurium sensitization are described in JP-A-9-23052.
No. 7 can be mentioned. Compounds preferably used in the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, and US Pat.
No. 448,060 and British Patent No. 618,061. Examples of shell-like compounds for reduction sensitization include ascorbic acid, thiourea dioxide, stannous chloride, hydrazine derivatives, borane compounds,
A silane compound, a polyamine compound, or 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.

The heat-developable photographic light-sensitive material of the present invention comprises, as spectral sensitizing dyes, cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, and hemioxonol dyes. Etc. can be used. For example, JP-A-63-1598
No. 41, No. 60-140335, No. 63-23143
No. 7, 63-259,651 and 63-304242
No. 63-15245, U.S. Pat. No. 4,639,41
No. 4, No. 4,740,455, No. 4,741,966
Nos. 4,751,175 and 4,835,096 can be used.

Useful spectral sensitizing dyes for use in the present invention include, for example, Research Disclosure (RD), section 17643 IV-A (p. 23, December 1978) and Item 1831X, p. 437 (August 1978, p. 437). Or cited in the literature cited. In particular, a spectral sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers and scanners can be advantageously selected. For example, JP-A-9-34
Compounds described in Nos. 078, 9-54409 and 9-80679 are preferably used.

Useful cyanine dyes are, for example, cyanine dyes having a basic nucleus such as a thiazoline nucleus, an oxazoline nucleus, a pyrroline nucleus, a pyridine nucleus, an oxazole nucleus, a thiazole nucleus, a selenazole nucleus and an imidazole nucleus.
Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as a thiohydantoin nucleus, a rhodanine nucleus, an oxazolidinedione nucleus, a thiazolinedione nucleus, a barbituric acid nucleus, a thiazolinone nucleus, a malononitrile nucleus and a pyrazolone nucleus. Including.

These spectral sensitizing dyes may be used alone or in combination, and the combination of spectral sensitizing dyes is often used particularly for supersensitization.

In addition to the spectral sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization.

Useful spectral sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are described in RD 176 Vol.
43 (issued in December 1978), page 23, IV, J, JP-B-49-25500, JP-B-43-4933, JP-A-59-19032, and JP-A-59-192242.

The organic silver salt of the present invention is a reducible silver source, and silver salts of organic acids and heteroorganic acids containing a reducible silver ion source, especially long chains (10 to 30, preferably 15 to 30).
Silver salts of aliphatic carboxylic acids having up to 28 carbon atoms) are preferred.

Organic or inorganic silver salt complexes whose ligands have a complex stability constant for silver ions of 4.0 to 10.0 are also useful. For example: Silver salts of organic acids (eg, gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, lauric acid, oleic acid, caproic acid, myristic acid, palmitic acid, maleic acid, linoleic acid, etc.), carboxyalkylthioureas ( For example, 1- (3-
Silver salts of carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc., and polymer reaction products of aldehydes with hydroxy-substituted aromatic carboxylic acids (for example, aldehydes (formaldehyde, acetaldehyde) , Butyraldehyde, etc.), silver salts or silver complexes of hydroxy-substituted acids (e.g., salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodisalicylic acid, etc.), thioenes (e.g.,
Silver salt or a silver complex of 3- (2-carboxyethyl) -4-hydroxymethyl-4-thiazoline-2-thioene and 3-carboxymethyl-4-thiazoline-2-thioene, etc., imidazole, pyrazole, urazole, 1,
Complexes or salts of silver with a nitrogen acid selected from 2,4-thiazole or 1H-tetrazole, 3-amino-5-benzylthio-1,2,4-triazole or benzotriazole; saccharin, 5-chlorosalicylaldoxime And silver salts of mercaptides. Examples of suitable silver salts are described in RD Nos. 17029 and 29963, and a particularly preferred silver salt is silver behenate.

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 can be obtained by a forward mixing method, a reverse mixing method, a simultaneous mixing method, and a method described in JP-A-9-12764.
A controlled double jet method as described in No. 3 is preferably used.

The shape of the organic silver salt of the present invention is not particularly limited, but needle crystals having a short axis and a long axis are preferred. As is well known in photosensitive silver halide light-sensitive materials, the inverse relationship between the size of silver salt crystal grains and their covering power also holds in the heat-developable photographic light-sensitive material of the present invention. When the size of the organic silver salt particles as the image forming portion of the material is large, it means that the covering power is small and the image density is low. Therefore, it is necessary to reduce the size of the organic silver salt particles.

The short axis of the organic silver salt particles of the present invention is 0.01 to
0.20 μm, the major axis is preferably 0.10 to 5.0 μm, the minor axis is 0.01 to 0.15 μm, and the major axis is 0.10 to 4.0 μm.
0 μm is more preferred.

The particle size distribution of the organic silver salt is preferably monodispersed. The monodispersion rate is expressed as a percentage of the value obtained by dividing the standard deviation of the length of each of the minor axis and major axis by the average value of each of the minor axis and major axis. Preferred monodispersion rate is 100% or less,
More preferably, it is 80% or less, still more preferably 50% or less. The shape of the organic silver salt particles can be measured from a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring the monodispersity, there is a method of determining the standard deviation of the volume-weighted average diameter of the organic silver salt particles, and the percentage (coefficient of variation) of the value divided by the volume-weighted average diameter is preferably 100% or less, It is more preferably at most 80%, further preferably at most 50%.

As a measuring method, for example, a particle size (volume load) obtained by irradiating a laser beam to organic silver salt particles dispersed in a liquid and obtaining an autocorrelation coefficient with respect to a time change of fluctuation of the scattered light is obtained. Average diameter).

In the photothermographic material of the present invention, the coating amount of the organic silver salt, especially the organic silver salt, is 1 m.
² per O. It is preferably from 5 to 5.0 g, more preferably from 1.0 to 5.0 g.
3.0 g is preferred.

As the reducing agent of the present invention, US Pat.
70,448, 3,773,512, 3,59
No. 3,863, and RD17029 and 29963, and include the following.

Aminohydroxycycloalkenones (eg, 2-hydroxypiperidino-2-cyclohexenone); aminoreductones as precursors of the reducing agent;
Esters (for example, piperidinohexose reductone monoacetate); N-hydroxyurea derivatives (for example, Np-methylphenyl-N-hydroxyurea);
Aldehyde or ketone hydrazones (e.g., anthracenaldehyde 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);
-Tetrazolylthiohydroquinones (e.g., 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (e.g.,
1,2,3,4-tetrahydroquinoxaline); amidooxines; azines (for example, a combination of an arylcarboxylic acid arylhydrazide and ascorbic acid);
Combinations of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine; hydroxanoic acids; combinations of azines and sulfonamidophenols; α-cyanophenylacetic acid derivatives; combinations of bis-β-naphthol and 1,3-dihydroxybenzene derivatives 5-pyrazolones; sulfonamidophenol reducing agents; 2-phenylindane-1,3-dione and the like; chromans; 1,4-dihydropyridines (eg, 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).

[0050]

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In the general formula (A), R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (for example, propyl,
Butyl, 2,4,4-trimethylpentyl, etc.), and R ′ and R ″ each represent an alkyl group having 1 to 5 carbon atoms (eg, each group such as methyl, ethyl, propyl, butyl, pentyl, etc.). ).

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

[0053]

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[0054]

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The amount of the reducing agent including the compound represented by formula (A) is preferably 1 × per mole of silver.
It is 10 ^-3 to 10 mol, especially 1 × 10 ^{-2 to} 1.5 mol.

The protective layer of the photothermographic material of the present invention contains a conductive metal oxide and oil, a conductive metal oxide and a polymer latex or a conductive metal oxide and a compound represented by the general formula (1). Is added.

It is preferable to provide two protective layers. The conductive metal oxide and oil, the conductive metal oxide and the polymer latex or the conductive metal oxide and the compound represented by the general formula (1) are added at the following positions. When it has two or more protective layers, it is preferable that the protective layer be provided between the outermost layer and the photosensitive layer.

The conductive metal oxide of the present invention is fine particles of a conductive metal oxide.

The conductive metal oxide fine particles of the present invention are
n, Ti, Sn, Al, In, Si, Mg, Ba, M
It is a conductive metal oxide fine particle (hereinafter, also referred to as a metal oxide colloid) containing an oxide of at least one metal selected from o, W and V as a main component.

Of these, ZnO, TiO ₂ and Sn
O ₂ is preferred, and SnO ₂ is more preferred. It is particularly preferable to add SnO ₂ sol to the coating solution.

Examples of doping with hetero atoms include Al and In for ZnO, and Nb and Ta for TiO ₂ .
For SnO ₂ , Nb, Sb, a halogen element and the like can be mentioned. The average particle diameter of the inorganic colloid particles is preferably 0.001 to 1 μm from the viewpoint of dispersion stability.

Regarding the method of producing the metal oxide colloid preferably used in the present invention, particularly the colloidal SnO ₂ sol composed of stannic oxide, a method of producing by dispersing SnO ₂ ultrafine particles in a suitable solvent, Any method may be used, such as a method of producing from a decomposition reaction of a soluble Sn compound in a solvent.

Regarding the method for producing SnO ₂ ultrafine particles,
In particular, temperature conditions are important, and methods involving high-temperature heat treatment are:
Undesirably, heat treatment should be performed at 300 ° C. or lower, preferably 200 ° C. or lower, more preferably 150 ° C. or lower, when it is unavoidable that heat treatment must be performed because a phenomenon of growing primary particles or increasing crystallinity occurs. However, 2
Heating from 5 ° C. to 150 ° C. is a means preferably selected when dispersion in the binder is considered.

In addition, with the recent advance in powder manufacturing technology, a method of spraying a compound manufactured by a wet method into an electric furnace and a method of high-temperature pyrolysis of an organometallic compound have been developed for manufacturing ultrafine particles. However, redispersing the ultrafine particles produced by such a method in a solvent involves considerable difficulty and is not economically preferable, and also has serious defects such as generation of agglomerated particles as a photosensitive material for photothermographic photography. Can cause For this reason, the method of redispersing in a solvent after the production process of isolating only the metal oxide is not employed in the present invention used as a photographic antistatic agent. However, when the compatibility between the binder and the solvent of the SnO ₂ sol is poor, it is necessary to replace the solvent,
In such a case, an appropriate amount of another compound having good compatibility or dispersion stability with the solvent of the SnO ₂ sol is added, and SnO 2
_The SnO ₂ ultrafine particles and the compound added in an appropriate amount from the ₂ sol are dried and separated by heating at 300 ° C. or less, preferably 200 ° C. or less, more preferably 150 ° C. or less, and then redispersed in another solvent.

A method for producing a Sn compound soluble in a solvent from a decomposition reaction in the solvent will be described below.

The Sn compound soluble in the solvent is K ₂
Compounds containing oxo anions such as SnO ₃ .3H ₂ O, water-soluble halides such as SnCl ₄ , R ′ ₂ Sn
A compound having a structure of R ₂ , R ₃ SnX, R ₂ SnX ₂ (where R and R ′ represent an alkyl group and X represents a halogen) such as (CH ₃ ) ₃ SnCl. (Pyridine), (C ₄
Organometallic compounds such as H ₉ ) ₂ Sn (O ₂ CC ₂ H ₅ ) ₂ ;
(SO ₄₎ can be cited oxo salts such as ₂ · 2H ₂ O. Using Sn compounds soluble in these solvents, SnO
_As a method for producing the ₂ sol, after dissolving in a solvent, a physical method such as heating and pressurizing, a chemical method such as oxidation, reduction, hydrolysis or a method of producing an SnO ₂ sol after passing through an intermediate or the like. is there.

As a production example, for example, Japanese Patent Publication No. 35-6616
The SnO ₂ sol manufacturing method described in JP, SnCl ₄
Is dissolved in 100 volumes of distilled water to form a precipitate of stannic hydroxide as an intermediate. Ammonia water is added to the stannic hydroxide to make it slightly alkaline and dissolved. Subsequently, the mixture is heated until the smell of ammonia disappears, whereby a colloidal SnO ₂ sol is obtained. In this example, water was used as the solvent, but methanol, ethanol, alcohol solvents such as isopropanol, tetrahydrofuran, dioxane, ether solvents such as diethyl ether, hexane, aliphatic organic solvents such as heptane, benzene, pyridine and the like. Various solvents such as an aromatic organic solvent can be used depending on the Sn compound, and the present invention is not particularly limited with respect to the solvent. Preferably, solvents such as water and alcohols are selected.

In the method for producing from a decomposition reaction of a Sn compound soluble in a solvent in a solvent, a compound containing an element other than Sn soluble in the solvent can be added during the process. For example, addition of a fluorine-containing compound soluble in a solvent,
This is the addition of a metal compound that can take a trivalent or pentavalent coordination number that is soluble in a solvent.

The fluorine-containing compound soluble in the solvent may be either an ionic fluoride or a covalent fluoride. For example HF, or KHF _2, SbF _3, MoF metal fluorides, such as _{6, NH 4 MnF 3, NH} 4 BiF 4 compound that produces fluoro complex anion such as, BrF _3, inorganic molecules such as SF _4, SF ₆ Fluoride, CF ₃ I, CF ₃ COOH, P
An organic fluorine compound such as (CF ₃ ) ₃ can be used, but when the solvent is water, a combination of a fluorine-containing compound and a nonvolatile acid such as a combination of CaF ₂ and sulfuric acid can also be used. .

Al, Ga, In, T, and T are compounds of metals soluble in a solvent and having a trivalent or pentavalent coordination number.
group element such as 1 or V such as P, As, Sb, Bi
Group elements, Nb capable of taking a trivalent or pentavalent coordination number,
A group of compounds containing transition metals such as V, Ti, Cr, Mo, Fe, Co, and Ni.

The particle size of the conductive metal oxide particles of the present invention is as follows:
The average particle size is preferably 100 μm or less, more preferably 10 μm or less. Further, if it is 1 μm or less, it can be used without any problem regarding transparency. However, the average particle size is 0.00
If the particle size is not larger than 01 μm, there is a problem in dispersion.

In the coating method using the conductive metal oxide particles and the organic binder, the addition amount is 60% or less, preferably 50% by volume in the binder after coating and drying.
The object of the invention is sufficiently achieved below, more preferably below 40%. However, the amount of such a powder is preferably small, preferably 30% or less, more preferably 20% or less. However, it is necessary to add a volume fraction of 0.01 or more, preferably 0.1 or more. Depending on the compound, it may be necessary to add 1% or more. There is no particular restriction.

From this volume fraction, the amount used was about 0.00005 to 1 g per m ^{2 of the} photothermographic material.
Thereby, good transparency and antistatic property can be obtained.

The layer containing a conductive metal oxide according to the present invention may contain a conductive polymer compound. These compounds are preferably, for example, polyvinylbenzene sulfonates, polyvinylbenzyltrimethylammonium chloride, quaternary salt polymers, polymer latex and the like.

Oil is dispersed and contained in the hydrophilic colloid layer of the protective layer of the photothermographic material of the present invention.

Here, oil is defined as having a solubility in water of 25.
It is less than 10% by weight at ° C and liquid at 25 ° C.

The average particle size of the oil droplets to be dispersed may be broad or narrow, but preferably the average oil droplet size is 0.1 to 0.4 μm.

For dispersion, various surfactants can be used. For example, US Pat. No. 2,332,027
Nos. 2,801,170 and 2,801,171, and anionic and nonionic surfactants described in JP-B-48-9979 can be used.

Hereinafter, typical specific examples of the oil that can be used in the present invention will be described.

Diethyl adipate, dibutyl adipate, diisobutyl adipate, di-n-hexylethyl adipate, dioctyl adipate, dicyclohexyl azelate, di-2-ethylhexyl azelate, dioctyl sebacate, diisooctyl sebacate, dibutyl succinate, octyl Stearate, dibenzyl phthalate, tri-o-cresyl phosphate, diphenyl-mono-p-tert-butylphenyl phosphate, monophenyl-di-o-chlorophenyl phosphate, monobutyl-dioctyl phosphate, 2,4-di-n- Amylphenol, 2,4-di-tert-amylphenol, 4-n-nonylphenol, 2-methyl-4-n-octylphenol, N, N-diethylcaprylamido, N, N- Ethyl lauramide, glycerol tripropionate, glycerol tributyrate, glycerol mono lactate acetate, tributyl citrate, acetyl triethyl citrate, di -2
-Ethylhexyl adipate, dioctyl sebacate,
Diisooctyl azelate, diethylene glycol dibenzoate, dipropylene glycol benzoate, triethyl citrate, tri (2-ethylhexyl) citrate, acetyl tri-n-butyl citrate, di (isodecyl) 4,5-epoxytetrahydrophthalate,
Oligovinyl ethyl ether, dibutyl phthalate, diisodecyl phthalate, polyethylene oxide (n>
16), glycerol tributyrate, ethylene glycol diprolobionate, di (2-ethylhexyl) isobutyrate, butyl laurate, tri- (2-ethylhexyl) phosphate, triphenyl phosphate,
Tricresyl phosphate, silicone oil, dimethyl phthalate, diethyl phthalate, dipropyl phthalate,
Dibutyl phthalate, isooctyl phthalate, diamino phthalate, di-n-octyl phthalate, diamyl naphthalene, triamyl naphthalene, monocaprin, monolaurin, monomyristin, monopalmitin, monostearin, monoolein, dicaprin, diproline, dimyristine, dipalmitine , Distearin, diolein, 1-stearo-2-palmitin, 1-palmit-3
-Stearin, 1-palmito-2-stearin, triacetin, tricaprin, trilaurin, trimyristin, tripalmitin, tristearin, triolein,
Tripetroserin, trielsin, triricinolein,
Linoleodiestearin, Oleodiesercin, Linoleoziercin, Palmito oleolinorenin, Paraffin, Linseed oil, Soybean oil, Eno oil, Kiri oil, Asami oil, Kaya oil,
Drying oils such as walnut oil, soy sauce oil, poppy oil, sunflower oil, azusa oil, kwai oil, safflower oil; cottonseed oil, corn oil, sesame oil, rapeseed oil, rice bran oil, lotus oil, mustard oil, pumpkin oil, Semi-dry oils such as dehydrated castor oil; peanut oil, olive oil, camellia oil, sasanqua oil, tea oil, castor oil, hydrogenated castor oil, almont oil, bundling oil, ben oil,
Oyster oil and the like can be mentioned. Further, compounds represented by the following general formula can also be used as the oil of the present invention.

[0081]

Embedded image

In the above formula, R ₉ represents an alkyl group having 1 to 8 carbon atoms.

Others JP-A-50-23823, 50
-62632, 51-26035, 51-26
Compounds other than those described in JP-A Nos. 036 and 51-26037 can be used in the same manner.

Among them, adipic acid, phthalic acid, sebacic acid, succinic acid, citric acid, fumaric acid, esters such as mazeleiic acid, isophthalic acid, phosphoric acid, esters of glycerin, paraffin and the like adversely affect the photothermographic material. It can be conveniently used because it is easily available without any problems, and it is chemically stable and easy to handle. Further dibutyl phthalate, diisodecyl phthalate, di-n-octyl phthalate, glycerol tripropionate,
Dioctyl sebacate, paraffin and silicone oil are mentioned as particularly preferred oils in the present invention.

In the present invention, when the oil is contained in the non-photosensitive hydrophilic colloid layer provided between the silver halide emulsion layer and the uppermost layer, a water-soluble or water-insoluble organic low-boiling compound may be used, if necessary. No problem. These evaporate after the coating and drying of the photothermographic material and hardly exist in the layer. Specific examples of these include, for example, methanol, ethanol, propyl alcohol, fluorinated alcohol, acetonitrile, dimethylamide, dioxane, methyl isobutyl ketone, diethylene glycol monoacetate, chloroform, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, cyclohexynol And cyclohexanetetrahydrofuran.

In the present invention, the oil droplets are mainly composed of the above-mentioned oils. The lipophilic photographic coupler, ultraviolet absorber, development inhibitor releasing compound, hydroquinone derivative,
An image fading inhibitor or the like may be contained in the oil droplets. However, when a large amount of lipophilic photographic additive is used, the pressure resistance of the photothermographic material is deteriorated.

The oil of the present invention is selected from those which can be dispersed in a coating solution without being mixed with the solution and which do not lose oil droplets even when the coating solution is coated and dried under ordinary conditions. . Preferred among these are those having a melting point of 25 ° C. or less even when used alone or in combination of two or more.
In addition, when used alone or when two or more kinds are mixed, those which are liquid at 25 ° C. are more preferable.

The oil droplets of the oil of the present invention may be of one kind or two kinds.
Oil droplets may be produced at the same time using more than one species, or separately emulsified and dispersed ones may be mixed and used.

Hereinafter, specific examples of the oil dispersion of the present invention will be shown.

Exemplary Oil Dispersion Dispersion Particle Size (μm) O-1: Tris (isopropylphenyl) phosphate 0.20 O-2: Trixyleryl phosphate 0.25 O-3: Tributyl phosphate 0.15 O-4 : Dioctyl phthalate 0.15 O-5: dibutyl phthalate 0.20 O-6: dihexyl phthalate 0.15 O-7: tricresyl phosphate 0.20 O-8: o-acetyltriethyl citrate 0.15 O- 9: N, N-dimethyl lauryl amide 0.10 O-10: diisodecyl phthalate 0.20 The addition amount of the oil of the present invention is preferably 10 to 1000 mg per 1 m ² of one side of the photothermographic material as an oil component, and more preferably 10 to 1000 mg. Is preferably 20 to 300 mg.

As the polymer latex of the present invention, a polymer latex generally used for a silver halide photographic light-sensitive material can be used. That is, it is a polymerizable ethylene-based compound or a polymerizable diolefin-based compound, and these are roughly classified into a hydrophobic monomer and a hydrophilic monomer. As the hydrophobic monomer, for example, methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, alkyl acrylates such as t-butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, Alkyl methacrylates such as 2-ethylhexyl methacrylate, t-butyl methacrylate and iso-propyl methacrylate; glycidyl esters such as glycidyl acrylate and glycidyl methacrylate; alkenyl benzenes such as styrene, vinyl toluene, α-methyl styrene and chloromethyl styrene Kind,
Vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether and phenyl vinyl ether; vinyl halides such as vinyl chloride, vinyl bromide and vinylidene chloride; acrylic amides and methacrylic amides Examples thereof include amides and diene monomers such as butadiene.

Examples of the hydrophilic monomer include hydroxyalkyl acrylates such as hydroxyethyl acrylate and hydroxypropyl acrylate, hydroxyalkyl methacrylates such as hydroxyethyl methacrylate and hydroxypropyl methacrylate, tetraethylene glycol, monomethacrylate and the like. Ethylene glycol (meth) acrylate, acrylic acid, methacrylic acid, itaconic acid, α-acrylamide-
2-methylpropanesulfonic acid monomer is exemplified. These monomers may be used alone or in combination of two or more kinds.When a hydrophilic monomer is used, it is preferable to use the monomer together with a hydrophobic monomer. Should not be used very often.

The polymer latex of the present invention may be obtained by an emulsion polymerization method or a suspension polymerization method in which the polymer is polymerized in a dispersion medium from the beginning, or may be separately polymerized to take out a polymer and redispersed to obtain a latex. Although an emulsion polymerization method may be used, an emulsion polymerization method is preferred from the viewpoint of production cost, dispersion stability, and the like.

The polymer latex of the present invention preferably has a Tg (glass transition temperature) of the polymer of -30 to 90 ° C. More preferably, it is 10 to 70 ° C.

The Tg of many polymers of the ethylenic monomers used in the present invention are described in "Polymer Handbook" by Brand Wrap et al., Pages III-139 to 179 (19).
1966 (Wiley & Sons), and the Tg (ＴK) of the copolymer is represented by the following formula.

Tg (copolymer) = V ₁ Tg ₁ + V ₂ Tg ₂
+ ... + V _w in Tg _W However Ueshiki, V _1, V ₂ is ... V _W represents the weight fraction of the monomer in the _{copolymer, Tg 1, Tg 2 ... Tg} W each monomer in the copolymer Represents the Tg (゜ K) of the homopolymer of Tg calculated according to the above equation has an accuracy of ± 5 ° C.

Hereinafter, preferred examples of the polymer latex of the present invention will be described, but the present invention is not limited thereto.

(P-1) St (20) MMA (70) MA (10) (P-2) St (15) MMA (75) MA (10) (P-3) St (50) MMA (35) MA (15) (P-4) St (25) MMA (70) MA (15) (P-5) St (40) MMA (55) AA (15) (P-6) St (20) EMA (70) ) AA (10) (P-7) St (10) MMA (75) AA (15) (P-8) St (10) MMA (80) acryloyloxyethyl orthophthalic acid (10) (P-9) St (15) MMA (75) acryloyloxyethyl succinate (10) (P-10) St (18) MMA (75) acryloyloxyethyl succinate (7) (P-11) CHMA (60) AIN (30) GMA
(10) (P-12) CHMA (80) AIN (15) GMA
(5) (P-13) CHMA (80) GMA (20) (P-14) CHMA (80) EMA (15) GMA
(5) (P-15) CHMA (65) EMA (25) GMA
(10) (P-16) n-butyl acrylate (10) t-butyl acrylate (35) styrene (25) hydroxyethyl methacrylate (30)

[0099]

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In the above-described exemplary polymer latex,
St: styrene, MMA: methyl methacrylate, EM
A: Ethyl methacrylate, MA: Methacrylic acid, A
A: acrylic acid, CHMA: cyclohexyl methacrylate, GMA: glycidyl methacrylate, AIN:-
_{CH 2 -C (COOC 9 H 19} iso) representative of H- (composition exhibits a weight fraction).

Next, the compound represented by formula (1) will be described.

In the general formula (1), R _{1 to} R ₈ are each a hydrogen atom, a halogen atom (for example, each atom of Cl, Br, I, etc.) and an alkyl group having 1 to 18 carbon atoms (for example, methyl group,
Ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, n-octyl, n-hexadecyl and the like, and alkoxy group having 1 to 8 carbon atoms (for example, methoxy group, ethoxy group, propoxy group, isopropyl) An oxy group, an n-butoxy group, an n-hexyloxy group, etc., a hydroxy group or a carboxyl group having 1 to 8 carbon atoms having one saturated aliphatic group (for example, CH ₃ COOH, CH ₃ CH ₂ CO
OH, (CH ₃ ) (CH ₂ ) ₂ COOH, (CH ₃ ) ₂ CH
COOH, (CH ₃ ) (CH ₂ ) ₃ COOH, etc.).

Next, specific examples of the compound represented by formula (1) of the present invention are shown below, but the present invention is not limited to these.

[0104]

Embedded image

The compounds represented by the general formula (1) of the present invention include all water-soluble compounds, oil-soluble compounds and latex compounds, and a method of applying these compounds to the protective layer of a light-sensitive material. Is dissolved in water or an organic solvent such as methanol, ethanol, acetone, dimethylacetone, dioxane, methyl ethyl ketone, acetonitrile, methyl acetate, and ethyl acetate, and then added to the coating solution for the protective layer.
In some cases, the following surfactant for dispersion may be used in combination.

When the compound represented by the general formula (1) is oil-soluble, the above-mentioned low-boiling organic solvent and a water-soluble and high-boiling organic solvent such as butyl phthalate, dioctyl phthalate and tricresyl phosphate are used. , Trihexyl phosphate, trioctyl phosphate, tricyclohexyl phosphate, triphenyl phosphate, dioctyl phenyl phosphate, hexyl oleate, dihexyl glutarate, butyl citrate, butyl myristate, butanediol dibenzoate, N,
N-diethyl laurylamide, behenic acid, octadecyl alcohol, chlorinated polyethylene and the like, and further, a dispersing surfactant such as an anionic surfactant, a nonionic surfactant, a cationic surfactant or an amphoteric surfactant (for example, sulfonic acid) , Sulfate, carboxylic acid, malic acid, boric acid polyalkylene oxide, polyglycerin, carboxybetaine, sulfobetaine ammonium, pyridium, etc.). Then, it may be added to the protective layer coating solution.

The photothermographic material of the present invention forms a photographic image by heat development. Reducible silver source (organic silver salt), catalytically active amount of silver halide, hydrazine derivative,
The photothermographic material preferably contains a reducing agent and, if necessary, a color tone agent for suppressing the color tone of silver in a state of being dispersed in an organic binder matrix.

The photothermographic material of the present invention is stable at room temperature, but is developed by heating to a high temperature (for example, 80 ° C. to 140 ° C.) after exposure. That is, heating produces 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.

In order to control the amount or wavelength distribution of light passing through the photosensitive layer of the photothermographic material of the present invention, a filter layer may be formed on the same side as or opposite to the photosensitive layer. A dye or a pigment may be included in the active layer. As the dye, compounds described in JP-A-8-201959 are preferable. The photosensitive layer may have a plurality of layers, and the sensitivity may be 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 forming layers.

The heat-developable photographic light-sensitive material of the present invention includes, for example,
Surfactants, antioxidants, stabilizers, plasticizers, ultraviolet absorbers, coating aids and the like may be used.

The binder preferably used in the photothermographic material of the present invention is transparent or translucent and generally colorless, and is a natural polymer synthetic resin, a polymer or a copolymer, or another film-forming medium such as gelatin, gum arabic. , Polyvinyl alcohol, hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl pyrrolidone, casein, starch, polyacrylic acid, polymethyl methacrylic acid, polyvinyl chloride, polymethacrylic acid, styrene-maleic anhydride copolymer, styrene- Acrylonitrile copolymer, styrene-butadiene copolymer, polyvinyl acetal (for example, polyvinyl formal and polyvinyl butyral), polyesters, polyurethanes,
Phenoxy resins, polyvinylidene chloride, polyepoxides, polycarbonates, polyvinyl acetate, cellulose esters, and polyamides. It may be hydrophilic or non-hydrophilic.

In the present invention, the amount of the binder in the photosensitive layer is preferably 1.5 to 10 for the purpose of preventing dimensional fluctuation after thermal development.
g / m ² . More preferably 1.7
８8 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.

In the photothermographic material of the present invention,
The protective layer on the photosensitive layer side preferably contains a matting agent. That is, a matting agent is provided on the surface of the photosensitive material in order to prevent the image after thermal development from being damaged.

The matting agent is preferably contained in a weight ratio of 0.5 to 10% based on all binders on the photosensitive layer side.

The material of the matting agent preferably used in the photothermographic material of the present invention may be either an organic substance or an inorganic substance. For example, as the inorganic substance, Swiss Patent 330,
No. 158, etc., French Patent 1,296,99
Glass powder described in No. 5, etc., British Patent 1,173,181
Or the like, or alkaline earth metals or carbonates such as cadmium and zinc, etc. described in the above item can be used as the matting agent. Examples of organic substances include starch described in U.S. Pat. No. 2,322,037, starch derivatives described in Belgian Patent No. 625,451 and British Patent No. 981,198, and Japanese Patent Publication No. 44-3643. Polyvinyl alcohol, polystyrene or polymethacrylate described in Swiss Patent No. 330,158, etc., US Pat. No. 3,079,257.
Polyacrylonitrile described in U.S. Pat.
An organic matting agent such as polycarbonate described in JP-A-2,169 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 its volume is converted into a sphere, and in the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere.

The matting agent preferably has an average particle size of 0.5 to 10 μm, more preferably 1.0 to 8.0 μm.
m. The coefficient of variation of the particle size distribution is 5
0% or less, more preferably 40%
Or less, 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 can be contained in any constituent layer, but is preferably a constituent layer other than the photosensitive layer, more preferably The outermost layer as viewed from the support.

The method of adding the matting agent may be a method of dispersing in a coating solution in advance and applying the same, or a method of applying the coating solution and spraying the matting agent before drying is completed. Is also good. When a plurality of types of matting agents are added, both methods may be used in combination.

It is preferable to add a color tone agent to the photothermographic material of the present invention. Toning agents are disclosed in U.S. Pat.
As shown in 080,254, 3,847,612 and 4,123,282, these materials are well known in the photographic art. An example of a suitable toning agent is RD170
No. 29, which includes the following.

Imides (eg, phthalimide); cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and , 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). Preferred toning agents are phthalazone or phthalazine.

The photothermographic material of the present invention may contain a mercapto compound or a disulfide compound for controlling development such as suppressing or accelerating development, improving spectral sensitization efficiency, or improving storage stability before and after development. , A thione compound or the like. When a mercapto compound is used, any structure may be used.
Those represented by Ar-SS-Ar are preferred. Where:
M is a hydrogen atom or an alkali metal atom, and Ar is a heteroaromatic or condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms.

Preferred heteroaromatic rings include benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzoterzole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine. ,
Pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogen (eg, Br and Cl), hydroxy, amino, carboxy, alkyl (eg, having one or more carbon atoms, preferably 1-4 carbon atoms) and alkoxy (eg, For example, it may have one selected from a substituent group consisting of one or more carbon atoms, preferably one having 1 to 4 carbon atoms.

Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole,
6-ethoxy-2-mercaptobenzothiazole, 2,
2'-dithiobisbenzothiazole, 3-mercapto-
1,2,4-triazole, 4,5-diphenyl-2-
Imidazole thiol, 2-mercaptoimidazole,
1-ethyl-2-mercaptobenzimidazole, 2-
Mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4- (3H) quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino- 6-hydroxy-2-mercaptopyrimidine monohydrate,
2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydroxy-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6- Diamino-2
Mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole, 2-mercapto-4-
Examples include phenyloxazole, but the present invention is not limited thereto.

The addition amount of these mercapto compounds is preferably in the range of 0.001 to 1.0 mol per mol of silver in the photosensitive layer, more preferably 0.01 to 1.0 mol per mol of silver.
It is an amount of 1 to 0.3 mol.

What is known as the most effective antifoggant is mercury ion. The use of a mercury compound as an antifoggant in a light-sensitive material is disclosed in, for example, US Pat. No. 3,589,903. However, mercury compounds are environmentally unfriendly. Non-mercury antifoggants include, for example, U.S. Pat. Nos. 4,546,075 and 4,452,885 and JP-A-59-57234.
Antifoggants such as those disclosed in US Pat.

Particularly preferred non-mercury antifoggants are disclosed in US Pat. Nos. 3,874,946 and 4,756,999.
-C (X ₁ ) (X ₂ ) as disclosed in US Pat.
(X ₃ ) (where X ₁ and X ₂ are halogen and X ₃ is hydrogen or halogen) and is a heterocyclic compound having one or more substituents. Examples of suitable antifoggants include paragraphs [0062] to [006] of JP-A-9-90550.
3].

The photosensitive layer of the photothermographic material of the present invention contains a polyhydric alcohol (for example,
Glycerin and diols of the type described in U.S. Pat. No. 2,960,404), fatty acids or esters described in U.S. Pat. Nos. 2,588,765 and 3,121,060, British Patent No. 955,061 The described silicone resin or the like can be used.

A hardener may be used in each layer such as the emulsion layer, the protective layer and the back layer of the photothermographic material of the present invention. Examples of the hardener include isocyanate compounds, epoxy compounds described in U.S. Pat. No. 4,791,042, and vinyl sulfone compounds described in JP-A-62-89048. Used.

The heat developable photographic light-sensitive material of the present invention has coatability,
A surfactant may be used for the purpose of improving charging and the like.
As an example of the surfactant, any of anionic, cationic, betaine, nonionic, and fluorine-based surfactants can be appropriately used. Specifically, Japanese Patent Application Laid-Open No. Sho 62-170950
No. 5,382,504, etc .; fluorine-containing surfactants described in JP-A-60-244945 and JP-A-63-188135; US Pat. And polyalkylene oxides and anionic surfactants described in JP-A-6-301140 and the like.

The heat-developable photosensitive emulsion used in the heat-developable photographic light-sensitive material of the present invention is prepared by dip coating, air knife coating, flow coating, or US Pat. No. 2,681,294.
Various coating methods can be used, including extrusion coating using a hopper of the type described in U.S. Pat. No. 2,761,791 and British Patent 837,09, as required.
According to the method described in No. 5, two or more layers can be simultaneously coated.

The support used in the photothermographic material of the present invention may be formed of a plastic film (for example, polyethylene terephthalate, polycarbonate, polyimide) in order to obtain a predetermined optical density after development and to prevent deformation of the image after development. , Nylon, cellulose triacetate, polyethylene naphthalate).

[0134] Among them, preferred supports include polyethylene terephthalate (hereinafter abbreviated as PET), polyethylene naphthalate (hereinafter abbreviated as PEN), and plastics containing a styrene polymer having a syndiotactic structure (hereinafter SPS). Abbreviated). The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm.

A plastic support which has been heat-treated 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 photosensitive layer is applied, at a temperature higher than the glass transition point of the support by 30 ° C. or more,
Preferably at a temperature higher than 35 ° C., more preferably 40 ° C.
Heating at a temperature higher than ℃. However, the effect of the present invention cannot be obtained by heating at a temperature exceeding the melting point of the support.

Exposure of the photothermographic material of the present invention is carried out by A
r laser (488 nm), He-Ne laser (63
3 nm), a red semiconductor laser (670 nm), an infrared semiconductor laser (780 nm, 830 nm) and the like.

[0137]

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 (Preparation of Photosensitive Silver Halide Emulsion A) 7.5 g of inert gelatin and 10 mg of potassium bromide were dissolved in 900 ml of water, the temperature was adjusted to 35 ° C. and the pH was adjusted to 3.0. 370 ml of an aqueous solution containing 74 g, an aqueous solution containing potassium bromide and potassium iodide in a molar ratio of (98/2), and potassium hexachloroiridate (III) were converted into 1 × 10 ⁻⁶ mol per mol of silver to pAg 7.7. The solution was added over 10 minutes by the controlled double jet method while keeping the temperature.
Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7
-Add 0.3 g of tetrazaindene and pH with NaOH
Was adjusted to 5 to obtain cubic silver iodobromide grains having an average grain size of 0.06 μm, a variation coefficient of the projected diameter area of 8%, and a (100) face ratio of 87%. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, desalting, and then phenoxyethanol 0.1%.
g, and adjusted to pH 5.9 and pAg 7.5 to obtain a silver halide emulsion.

Next, 3 × 10 ^-2 mol of sodium thiosulfate per mol of silver was added to the silver halide emulsion to obtain 55%.
The reaction was carried out at 60 ° C. for 60 minutes for chemical sensitization. afterwards,
After the temperature of the silver halide emulsion was lowered to room temperature, a photosensitive silver halide emulsion A was prepared by adding an antifoggant and the like described below.

(Preparation of Na Behenate Solution) 34 g of behenic acid was dissolved in 340 ml of isopropanol at 65 ° C. Next, while stirring, a 0.25N sodium hydroxide solution was added so as to have a pH of 8.7. At this time, about 400 ml of the sodium hydroxide solution was required. Next, the sodium behenate solution was concentrated under reduced pressure to adjust the concentration of sodium behenate to 8.9% by weight.

(Preparation of silver behenate) 2.9 ml of a solution prepared by dissolving 30 g of ossein gelatin in 750 ml of distilled water.
A 4 mol silver nitrate solution was added to adjust the silver potential to 400 mV.
In this, the controlled double jet method is used to add 78
At a temperature of ° C., 374 ml of the sodium behenate solution was added at a speed of 44.6 ml / min, and at the same time, a 2.94 mol silver nitrate solution was added so that the silver potential became 400 mV. The amounts of sodium behenate and silver nitrate used at the time of addition were 0.092 mol and 0.101 mol, respectively.

After the addition was completed, the mixture was further stirred for 30 minutes, and the water-soluble salts were removed by ultrafiltration.

(Preparation of Photosensitive Emulsion) To this silver behenate dispersion, 0.01 mol of the silver halide emulsion A was added, and 100 g of a solution of polyvinyl acetate in n-butyl acetate (1.2 wt%) was further stirred. Is gradually added to form a floc of the dispersion, water is removed, water is further washed twice and water is removed, and 2.5% by weight of butyl acetate of polyvinyl butyral (average molecular weight 3000) is used as a binder. 60 g of a 1: 2 mixed solution of isopropyl alcohol and isopropyl alcohol was added with stirring. Polyvinyl butyral (average molecular weight: 4000) and isopropyl alcohol were added and dispersed as a binder to the gel-like mixture of behenic acid and silver halide thus obtained.

(Preparation of photosensitive material) The following layers were sequentially formed on a PET support to prepare a sample photosensitive material. The drying was performed at 75 ° C. for 5 minutes.

<Back surface side coating> A liquid having the following composition was applied so as to have a wet thickness of 80 μm.

Polyvinyl butyral (10% isopropanol solution) 150 ml Dye-B 70 mg Dye-C 70 mg C ₈ F ₁₇ SO ₃ Na 2 mg C ₇ F ₁₅ CH ₂ (OCH ₂ CH ₂ ) ₁₃ -OH 15 mg SiO _{2 with a} particle size of 3 μm 5mg particles

[0147]

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<Coating on Photosensitive Surface> Coating solutions for the first layer, second layer and third layer having the following formulations were applied in the order of proximity to the support.

<First Layer: Photosensitive Layer> A liquid having the following composition was applied so that the amount of silver applied was 2.0 g / m ² and polyvinyl butyral as a binder was 6.5 g / m ² .

Photosensitive Silver Halide Emulsion A Amount of 0.1 g / m ² in silver amount Amount of 1.9 g / m ² silver behenate silver Sensitizing dye-1 (0.1% N, N -Dimethylformamide solution) 2 mg Antifoggant-1 (0.01% methanol solution) 3 ml Antifoggant-2 (1.5% methanol solution) 8 ml Antifoggant-3 (2.4% N, N-dimethylformamide Solution) 5 ml Phthalazone (4.5% N, N-dimethylformamide solution) 8 ml Developer-1 (10% acetone solution) 13 ml Hardening agent-H (1% methanol: N, N-dimethylformamide = 4: 1 solution) ) 2ml

[0151]

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[0152]

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<Second Layer: Protective Layer (Lower Layer)> A solution having the following composition was applied onto each photosensitive layer so that the amount of cellulose acetate applied was 0.5 g / m ² .

Acetone 175 ml 2-propanol 40 ml methanol 15 ml cellulose acetate 8.0 g phthalazine 1.0 g 4-methylphthalic acid 0.72 g tetrachlorophthalic acid 0.22 g tetrachlorophthalic anhydride 0.5 g Comparative compounds A, B Table 1 Described in Table 1. Conductive metal oxide: SnO ₂ sol (solid content) described in Table 1 Protective layer additive described in Table 1 <third layer: protective layer (upper layer)> A liquid having the following composition was coated with cellulose acetate. Coating was performed on each photosensitive layer so that the amount became 1.6 g / m ² .

Acetone 175 ml 2-propanol 40 ml methanol 15 ml cellulose acetate 8.0 g phthalazine 1.0 g 4-methylphthalic acid 0.72 g tetrachlorophthalic acid 0.22 g tetrachlorophthalic anhydride 0.5 g monodisperse having an average particle size of 4 μm 1 w / w% based on silica binder Comparative compounds A and B (antistatic agent) described in Table 1 Conductive metal oxide: SnO ₂ sol (solid content) described in Table 1 Protective layer additive described in Table 1 <Undercoat layer> The following undercoat layer was provided between the support and the photosensitive layer. The amount of addition is shown in an amount per 1 m ² .

Conductive metal oxides: SnO ₂ sol (solid content) Table 1 Copolymer latex of n-butyl acrylate (40% by weight), styrene (20% by weight) glycidyl methacrylate (40% by weight) _{300mg (C 9 H 19) 2} -C 6 H 3 -O- (CH 2 CH 2 O) 12 -SO 3 Na 4.0mg (C 9 H 19) 2 -C 6 H 3 -O- (CH 2 CH About ₂ O) ₁₂ -H 1.0mg (evaluation of sample) obtained sample film was subjected to characteristic evaluation described below.

<Measurement of Surface Resistivity After Heat Treatment> The prepared sample film was conditioned at 23 ° C. and 20% RH for 2 hours.
The surface resistivity (Ω) on the photosensitive layer side was measured using a resistance meter R-503 and an electrode P-616 (both manufactured by Kawaguchi Electric Works).

The surface resistivity σ (Ω) was determined by the following equation.

Σ = (p / g) Rs Rs: measured value of surface resistance (Ω) g: distance between electrodes (m) p: effective length of main electrode (m) The measured surface resistivity is logΩ in Table 1. Indicated by

<Evaluation with film>
Leave at 3 ° C. and 80% RH for 2 hours, and use a cutter blade on the photosensitive layer side at 90 ° and 45 ° angles to the photosensitive material, width 5c.
m, cut one by one until reaching the support, attach a cellophane tape (manufactured by Nichiban Co., Ltd.) of 30 cm in length and 2.5 cm in width, hold the end of the cellophane tape with one hand, and use one hand The cellophane tape was instantaneously peeled off while holding the sample, and the state of the film peeling of the sample at that time was visually evaluated according to the following evaluation criteria.

1: Much peeling of the film is impossible, and practical use is impossible. 2: Much peeling of the film is a problem in practical use. 3: There is peeling of the film, but there is no problem in practical use. Good 5: Very good without film peeling.

Table 1 shows the above results.

[0163]

[Table 1]

From Table 1, it can be seen that the protective layer of the present invention comprises a combination of a conductive metal oxide and an oil, a conductive metal oxide and a polymer latex, a conductive metal oxide and a compound represented by the general formula (1). It can be seen that the heat-developable photographic material containing organic silver particles, photosensitive silver halide particles and a reducing agent has a low surface resistivity after the heat treatment and also has good film formation.

[0165]

According to the present invention, a heat-developable photographic light-sensitive material having a low surface resistance (surface electric resistance: Ω) after heat development and a good film-forming performance can be obtained.

Claims (5)

[Claims] 1. A photothermographic material comprising a support having an organic silver salt, photosensitive silver halide particles and a reducing agent, and a protective layer containing a conductive metal oxide and an oil. . 2. A photothermographic method comprising a support having an organic silver salt, photosensitive silver halide particles and a reducing agent, and a protective layer containing a conductive metal oxide and a polymer latex. material. 3. The photothermographic material according to claim 2, wherein the polymer latex has a Tg (glass transition temperature) of -30 to 90 ° C. 4. A support having a protective layer containing an organic silver salt, photosensitive silver halide particles and a reducing agent, and containing a conductive metal oxide and a compound represented by the following general formula (1). A photothermographic material comprising: Embedded image [Wherein, R _{1 to} R ₈ each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a hydroxy group or a saturated aliphatic monocarboxylic acid group. ] 5. The photothermographic material according to claim 1, wherein the conductive metal oxide is SnO ₂ .