JP2001048902A - Composite fine grains containing water dispersible organic silver salt and its production, composite fine grains containing water dispersible reducing agent and its production, and silver halide photosensitive material for heat developing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composite fine grains useful for production of silver halide photosensitive material for heat developing, low in photographic fog even produced by using an aqueous coating agent and stored in an atmosphere having high humidity by forming the composite fine grains containing a specific silver source or a reducing agent in an aqueous liquid. SOLUTION: This composite fine grains including water dispersible organic silver salt are obtained by forming composite fine grains by polymerizing (B) a polymerizable monomer in an aqueous solution including (A) an organic silver salt. The preferable ratio of the component A and B is 0.5-10 pts.wt of the component B per 1 pts. of the component A. The component B preferably satisfies log P>=2.0 and includes a crosslinkable monomer. The preferable glass transition pint of the polymer of the composite fine grains is room temperature-120 deg.C, especially 40-100 deg.C. The composite fine grains including a water dispersible reducing agent are obtained by including the reducing agent in a resin and then forming the fine grains in an aqueous liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a silver halide photographic light-sensitive material for thermal development, and more particularly, to a silver halide photographic light-sensitive material for thermal development which can be produced with an aqueous coating solution.

[0002]

2. Description of the Related Art There are many known photosensitive materials having a photosensitive layer on a support and forming an image by exposing the image. Among them, as a system capable of environmental preservation and simplification of image forming means, there is a technique of a silver halide photographic light-sensitive material for thermal development for forming an image by thermal development.

The details of silver halide photographic light-sensitive materials for thermal development are described in, for example, US Pat. Nos. 3,152,904 and 3,457,075 and "Dry Silver Photography".
c Material) "(D. Morgan
n)), "Heat treated silver systems (Ther
Mally Processed Silver Sy
stems) "(D. Morgan,
B. Shelly), "Imaging Processes and Materials (Imaging).
Processes and Material
s) "Neblette 8th Edition (Sturgi (Stur
ge), V.I. Walworth,
A. Edited by Shepp (1969) 2nd
Page.

A silver halide photographic light-sensitive material for thermal development is one which forms a photographic image by thermal development after exposure, and comprises a reducible silver source (organic silver salt), a catalytically active photocatalyst silver halide, A reducing agent and, if necessary, a toning agent for suppressing the color tone of silver are usually contained in a matrix of a hydrophobic resin in a state where these functions are dispersed, and are stable at ordinary temperature. 140 ° C.). Heating generates silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. The silver formed by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image.
This reaction process proceeds without supplying a processing liquid such as water from the outside.

A silver halide photographic light-sensitive material for thermal development which forms an image by such thermal development meets the requirements for simplification of development processing and environmental preservation, which are increasing more and more in recent years.

However, conventionally, most of such silver halide photographic light-sensitive materials for thermal development have been formed by applying an organic solvent-based coating solution and drying to form a photosensitive layer. For example, U.S. Pat. No. 5,415,993 describes the use of a coating solution of polyvinyl butyral in organic solvent of toluene and methyl ethyl ketone. In addition, there is an example in which a photosensitive layer is formed by using a coating solution using an organic solvent such as 2-butanone or methanol as a solvent. However, it is not preferable from the viewpoint of the problem of solvent vapor at the manufacturing site, the problem of environmental conservation such as difficulty in complete recovery of the solvent, and the problem of safety.

A technique for forming a photosensitive layer using a water-based coating solution which is advantageous in this respect has been proposed. For example, JP
Examples of a photosensitive layer using gelatin as a binder are described in JP-A Nos. 9-52626 and 53-116144, examples of a photosensitive layer using polyvinyl alcohol as a binder are described in JP-A-50-151138, and further, JP-A-58-
No. 28737 describes an example of a photosensitive layer using a water-soluble polyvinyl acetal as a binder. However, these systems have the drawback that fog is increased in a high humidity atmosphere and the stability is lacking.

In general, a protective layer of a photosensitive layer is provided on a photosensitive material for the purpose of protecting an image and improving transparency. In addition, a back layer, a protective layer for the back layer is provided for the purpose of improving handleability, improving resolution and sharpness by an antihalation effect, and such a method is known in the art and widely adopted. I have. In general, photosensitive materials are often stored in sheets or rolls, and are often commercialized. In such a case, the photosensitive material is stored in a state where the front surface and the back surface are overlapped. However,
In the silver halide photographic light-sensitive material for thermal development in which a photosensitive layer is formed using the above-described aqueous solvent coating solution, the flaw is particularly increased when the front and back surfaces are stored in a high-humidity atmosphere with the front and back surfaces overlapped. was there.

Therefore, there has been a demand for a technique for providing a silver halide photographic light-sensitive material for thermal development which can be produced without using an organic solvent and has less fog even when stored in a high humidity atmosphere.

[0010]

In order to solve such problems, a technique of applying an aqueous coating solution using a polymer latex to which a silver halide, an organic silver salt, a reducing agent, a color tone agent, and the like have been added. Proposed. For example, JP-A-10-
Nos. 186,565 and 11-08,574. However, these are susceptible to a dark reaction, and have a problem of storage stability against heat and humidity.

An object of the present invention is to produce a coating solution using a water-based solvent which is advantageous in terms of environmental protection, safety, manufacturing costs, etc., and to further reduce heat generation even when stored in a high humidity atmosphere. An object of the present invention is to provide a silver halide photographic light-sensitive material for development.

[0012]

The present invention has the following constitution.

(1) In an aqueous solution containing an organic silver salt,
A method for producing composite fine particles containing a water-dispersible organic silver salt, wherein composite fine particles are formed by polymerizing a polymerizable monomer.

(2) When the polymerizable monomer is log P ≧
Characterized by having a value of 2.0 (1)
The method for producing composite fine particles containing a water-dispersible organic silver salt according to the above.

(3) The method for producing water-dispersible organic silver salt-containing composite fine particles according to (1) or (2), wherein the polymerizable monomer contains a crosslinkable monomer.

(4) A method for producing composite fine particles containing a water-dispersible reducing agent, characterized in that the resin contains a reducing agent and the composite is formed in an aqueous liquid.

(5) Water-dispersible organic silver salt-containing composite fine particles formed by the method according to any one of (1) to (3).

(6) Water-dispersible reducing agent-containing composite fine particles formed by the method described in (4).

(7) A silver halide photographic light-sensitive material for thermal development, having a photosensitive layer containing a photosensitive silver halide on a support, containing an organic silver salt and a reducing agent for the organic silver salt, A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible organic silver salt-containing composite fine particles according to (5).

(8) A silver halide photographic light-sensitive material for thermal development, having a photosensitive layer containing a photosensitive silver halide on a support, containing an organic silver salt and a reducing agent for the organic silver salt, A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible reducing agent-containing composite fine particles according to (6).

(9) In a silver halide photographic light-sensitive material for heat development, having a photosensitive layer containing a photosensitive silver halide on a support, containing an organic silver salt and a reducing agent for the organic silver salt, A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible organic silver salt-containing composite fine particles described in (7) and the water-dispersible reducing agent-containing composite fine particles described in (8).

(10) The halogenation for thermal development according to any one of (7) to (9), wherein the photosensitive layer has water-soluble polymer and / or water-dispersible polymer particles as a binder. Silver photographic photosensitive material.

(11) The silver halide photographic light-sensitive material for thermal development according to (10), wherein 5% by weight or more of the binder is a water-soluble polymer.

(12) The silver halide photographic light-sensitive material for thermal development according to (10) or (11), wherein the water-soluble polymer is gelatin.

The heat-developable silver halide photographic light-sensitive material of the present invention comprises, on a support, a photosensitive silver halide, an organic silver salt,
The layer containing the organic silver salt reducing agent was applied as an aqueous coating solution. In this layer, all or most of the organic silver salt contained water-dispersible organic silver salt-containing composite fine particles. It is characterized in that the formed organic silver salt and the reducing agent in which all or most of the reducing agent forms the water-dispersible reducing agent-containing composite fine particles are isolated as independent fine particles, respectively. Therefore, excellent storage stability against heat and humidity is a feature of the silver halide photographic light-sensitive material for thermal development of the present invention.

Hereinafter, the present invention will be described in detail.

First, the organic silver salt will be described.

The organic silver salt used in the present invention is a reducible silver source, a silver salt of an organic acid and a heteroorganic acid containing a reducible silver ion source, and the ligand is 4.0 to 4.0. 10.
Organic or inorganic silver salt complexes having a total stability constant for silver ions of 0 are also useful. Examples of silver salts suitable for the invention include:
Research Disclosure (hereinafter abbreviated as RD) 17029 and 29996, and silver salts of organic acids (for example, gallic acid, oxalic acid, behenic acid,
Silver salts of arachidic acid, stearic acid, palmitic acid, lauric acid and the like), silver salts of carboxyalkylthioureas (for example, 1- (3-carboxypropyl) thiourea, 1-
(3-carboxypropyl) -3,3-dimethylthiourea and other silver salts), and silver complexes of polymer reaction products of aldehydes and hydroxy-substituted aromatic carboxylic acids (for example, aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.) Silver complexes), silver salts of hydroxy-substituted acids (eg, silver salts of salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodisalicylic acid, etc.), silver salts or complexes of thioenes (eg, 3 -(2-carboxyethyl) -4-hydroxymethyl-4- (silver salt or complex such as thiazoline-2-thioene and 3-carboxymethyl-4-thiazoline-2-thioene), imidazole, pyrazole, urazole, 1 , 2,4-thiazole or 1H-tetrazole, 3-amino-5-benzylthio-1,2 Complex addition salts with nitrogen acid silver selected from 4-triazole or benzotriazole, saccharin, a silver salt such as 5-chloro salicylaldoxime,
And silver salts of mercaptides. Of these, long-chain (10 to 30, preferably 15 to 25, carbon atoms) aliphatic carboxylic acids and nitrogen-containing heterocycles are preferred. Particularly preferred silver sources are silver behenate, silver arachidate and / or silver stearate.

These organic silver salts can be obtained by mixing a water-soluble silver compound and a compound that forms a complex with silver.
Forward mixing method, reverse mixing method, simultaneous mixing method, JP-A-9-1276
The controlled double jet method as described in JP-A-43-43 is preferably used. For example, after adding an alkali metal salt (eg, sodium hydroxide, potassium hydroxide, etc.) to an organic acid to form an organic acid alkali metal salt soap (eg, sodium behenate, sodium arachidate, etc.), control double jet Then, the soap and silver nitrate are added to form 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 1
It is preferably not more than μm and monodispersed. The average particle size of the organic silver salt is, for example, when the particles of the organic silver salt are spherical, needle-shaped, rod-shaped, flat-shaped or the like, the diameter when considering a sphere equivalent to the volume of the organic silver salt particles. Say. The average particle size is preferably 0.01 μm to 0.8 μm, particularly 0.05 μm.
m to 0.5 μm is preferred. In the present invention, the organic silver salt is more preferably monodisperse particles having an average particle size of 1 μm or less. By setting the content in this range, an image having a high density can be obtained. Further, the organic silver salt preferably has tabular grains having 60% or more of the total organic silver. In the present invention, the tabular grains refer to those having an aspect ratio (abbreviated as AR) of 3 or more, which is a ratio between the average particle diameter and the thickness, which is represented by the following formula.

AR = average particle size (μm) / thickness (μm) In order to form the organic silver salt into these shapes, the organic silver salt crystals are dispersed and pulverized with a ball mill or the like with a binder or a surfactant. Is obtained.

The shape of the organic silver salt that can be used in the present invention may be a needle-like crystal having a short axis and a long axis. In the present invention, the short axis is 0.01 to 0.20 μm.
m, the major axis is preferably 0.10 to 5.0 μm, and the minor axis is 0.0
More preferably, the length is 1 to 0.15 μm and the major axis is 0.10 to 4.0 μm. Monodispersion in the case of a needle-shaped crystal means 100% or less, more preferably 80% or less, of the value obtained by dividing the standard deviation of the length of each of the minor axis and major axis by the minor axis and major axis, respectively. , More preferably 50% or less. The shape of the organic acid salt can be determined from a transmission electron microscope image of the organic silver salt dispersion. The particles of the organic silver salt are preferably monodispersed. Here, the monodispersion has the same meaning as in the case of silver halide, and preferably has a monodispersity of 1 to 1.
30. As another method for measuring the monodispersity, there is a method of calculating the standard deviation of the volume-weighted average diameter of the organic silver salt, and the percentage divided by the volume-weighted average diameter (coefficient of variation) is calculated by this method. According to this, preferably 100
%, More preferably 80% or less, still more preferably 5% or less.
0% or less. As a measuring method, for example, the organic silver salt dispersed in the liquid is irradiated with laser light, and the particle size (volume weight average diameter) obtained by obtaining an autocorrelation function for the time change of the fluctuation of the scattered light is obtained. Can be done.

The organic silver salt used in the present invention prepared as described above is preferably subjected to desalting of a salt such as an alkali metal soap used. The desalting method is not particularly limited, and a known method can be used. A known filtration method such as centrifugal filtration, suction filtration, ultrafiltration, and floc-forming water washing by a coagulation method can be preferably used.

The composite fine particles containing a water-dispersible organic silver salt of the present invention will be described.

The water-dispersible organic silver salt-containing composite fine particles of the present invention are prepared by allowing a polymerizable monomer to coexist in an aqueous liquid containing an organic silver salt as a solid fine particle dispersion as described above, and polymerizing the polymerizable monomer. Thus, composite fine particles in which an organic silver salt and a polymer are mixed are formed.

The constitution (1) of the present invention is a method for producing composite fine particles containing a water-dispersible organic silver salt. The water-dispersible organic silver salt-containing composite fine particles are, in an aqueous liquid containing an organic silver salt,
It is obtained by polymerizing a polymerizable monomer.

Here, the aqueous liquid in the present invention means water itself or a liquid containing a substance that helps dissolve or disperse another substance in water. The substance that assists dissolution or dispersion includes an organic solvent compatible with water, a surfactant, and a water-soluble polymer having surfactant.

Examples of the organic solvent compatible with water include methanol, ethanol, propanol, acetic acid, acetone, dioxane, ethylene glycol and the like.

Examples of the surfactant include nonionic surfactants, cationic surfactants, anionic surfactants, and betaine-type surfactants such as sodium laurate, sodium dodecyl sulfate, and 1-octoxycarbonylmethyl-1. −
Sodium octoxycarbonylmethanesulfonate, sodium dodecylnaphthalenesulfonate, sodium dodecylbenzenesulfonate, sodium dodecylphosphate, cetyltrimethylammonium chloride, dodecyltrimethyleneammonium chloride, N-2-ethylhexylpyridinium chloride, polyoxyethylene nonylphenyl ether, Examples thereof include polyoxyethylene sorbitan laurate ester.

Examples of the water-soluble polymer having a surfactant include polyvinyl alcohol, acrylamide, N-vinylpyrrolidone, acrylic acid or salt, methacrylic acid or salt, maleic anhydride, acryloylmethylpropanesulfone, hydroxyethyl acrylate, and the like. Polyvinylpyridine quaternary salt, synthetic anionic water-soluble polymer such as homopolymer or copolymer such as N-vinylimidazole, synthetic nonionic water-soluble polymer, synthetic cationic water-soluble polymer, carboxymethyl cellulose salt, carboxymethyl starch salt, Semi-synthetic ionic water-soluble polymers such as alginate and pectate, semi-synthetic nonionic water-soluble polymers such as hydroxyethylcellulose, hydroxypropylcellulose and hydroxymethylpropylcellulose Rimmer, it can be mentioned polymers, etc. present in the gelatin and the like nature. These water-soluble polymers serve as a dispersion stabilizer for the water-dispersible organic silver salt-containing composite fine particles of the present invention.

In the present invention, when the organic silver salt is dispersed,
An organic solvent compatible with water, a surfactant, and a water-soluble polymer having surfactant may be used as appropriate, and may be used alone or in combination. In particular, use a surfactant and a water-soluble polymer having surfactant in combination to disperse, or after dispersing with a surfactant, add a water-soluble polymer having surfactant to stabilize the dispersion. Preferably.

The aqueous solution contains a surfactant or a water-soluble polymer having a surface activity with respect to an organic silver salt in an amount of 10 to 1%.
It is preferable to contain 50% by weight. More preferably, it is 30 to 100% by weight.

Next, a method for dispersing the organic silver salt will be described. Adding an organic silver salt to the aqueous liquid, a stirrer having a stirring blade, a high-pressure homogenizer, a colloid mill, an ultrasonic dispersion tumbler type mixer, a ball mill, a vibration ball mill, a planetary ball mill, a sand mill, a colloid mill, a jet mill, Any of a roller mill and the like may be used, and these mechanical dispersion methods can be appropriately selected and combined. The dispersed particle size is 3 μm or less in average particle size, preferably 500
nm or less. This is called a solid fine particle dispersion of an organic silver salt.

In the method of polymerizing a polymerizable monomer in an aqueous solution containing an organic silver salt according to the present invention, the polymerizable monomer may be added to the aqueous solution at the same time as the organic silver salt and polymerized. After being dispersed in the aqueous liquid, the polymerizable monomer may be added and dispersed, or the polymerization may be performed while dispersing. The method for adding the polymerizable monomer is preferably dropping. In order to polymerize the polymerizable monomer in an aqueous solution containing an organic silver salt, a polymerization method such as suspension polymerization, slurry polymerization, or emulsion polymerization is used, but emulsion polymerization is preferred. A polymerization initiator used for ordinary emulsion polymerization can be used. Benzoyl peroxide and its derivatives (for example, p, p'-dimethoxy, p,
p'-di-t-butyl, m, m'-dinitro, etc.), potassium peroxide, ammonium peroxide, lauroyl peroxide,
t-butyl peroctoate, t-butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide, isopropyl-carbonate, 2,
4-dichlorobenzyl peroxide, methyl ethyl ketone peroxide, azonitrile compounds (for example,
Azobisbutyronitrile, 2,2'-azobis (2-amidinopropane) hydrochloride, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-
Sodium azobis (oxycarbonylpropane), hydrogen peroxide, hydrogen peroxide / ferrous salt, potassium persulfate / ferrous acid sulfite, cumene hydroperoxide / ferrous salt, benzoyl peroxide / dimethylaniline, etc. Can be mentioned. Redox polymerization type polymerization initiator, hydrogen peroxide, hydrogen peroxide / ferrous salt, potassium persulfate / acid ferrous sulfite, cumene hydroperoxide / ferrous salt, benzoyl peroxide / dimethylaniline, etc. preferable. Those which do not affect the organic silver salt are preferred.
The polymerization initiator may be added at the time of dispersion of the organic silver salt, or may be added after the dispersion.

Since the organic silver salt of the present invention is sensitive to heat, polymerization at a low temperature is preferred, and redox polymerization at 80 ° C. or lower, more preferably at 60 ° C. or lower is preferred.

In the present invention, as the polymerizable monomer using the dispersed organic silver salt as composite fine particles, a hydrophobic polymerizable monomer is preferable, and a hydrophobic ethylenically unsaturated monomer is particularly preferable. For example, acrylates or methacrylates include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, i-propyl acrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl Acrylate, s-butyl acrylate, t-butyl acrylate, n-butyl methacrylate, s-butyl methacrylate, t-butyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, 2-cyanoethyl acrylate, 2-cyanoethyl methacrylate, phenyl acrylate, Benzyl acrylate, phenethyl acrylate, phenyl methacrylate, benzyl methacrylate, Active monomers such as tyl methacrylate, 4-chlorobenzyl methacrylate, glycidyl acrylate, and glycidyl methacrylate include 2-acetoacetoxyethyl methacrylate, 2-acetoacetoxyamidoethyl acrylamide, 2-cyanoacetoxyethyl methacrylate, and N-4- (acetoacetoxyethyl Examples of vinyl esters such as acetoxybenzyl) methacrylate include vinyl acetate, vinyl propionate, vinyl pivalate, and vinyl trifluoroacetate. Examples of acrylamide or methacrylamide include Nt-butylacrylamide and N, N-butylacrylamide. Nn-dibutylacrylamide, β-cyanoethylacrylamide, Nt-butylmethacrylamide, N, Nn-dibutylmethacrylamide, β-cyanoethyl Takuriruamido etc., as the styrenes, such as styrene, methyl styrene, dimethyl styrene,
Trimethylene styrene, ethyl styrene, isopropyl styrene, chloro styrene, methoxy styrene, acetoxy styrene, chloro styrene, dichloro styrene, bromo styrene, methyl vinyl benzoate, etc., and acrylonitrile, vinylidene chloride, phenyl vinyl ketone, etc. Can be done.

The log P in the constitution (2) of the present invention is a parameter indicating hydrophobicity / hydrophilicity, and is usually n-
It can be determined from the partition coefficients of the substances in the two solvent systems to octanol and water, and these can be obtained from Chemical Domain Supplement No. 122 “Structure-Activity Relationship of Drugs” (Nankodo) 73-10
It is described in detail on page 3. In recent years, a method of calculating logP by calculation has been proposed, and a particularly useful method is Molecular Design Inc. (Molecular D).
design Limited) software “CHE
MLAB-II Revision 10.02 ". The term logP in the present invention refers to this software "CHEMLAB-II Revision".
10.02 ”.

In the constitution (2) of the present invention, when the organic compound of the organic silver salt is an organic acid, a long-chain aliphatic carboxylic acid is generally used, so that the monomers also have a hydrophobic group from the viewpoint of compatibility. Preferably, log P (calculated value, U.S. Pat. No. 5,455,320, column 4,
(Described in lines 1 to 7) is preferably 2.0 or more, and neopentyl methacrylate, 3,3-dimethylbutyl methacrylate, cyclohexyl methacrylate,
i-amyl methacrylate, 3,3-dimethylbutyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate (dodecyl methacrylate), tridecyl methacrylate, hexadecyl methacrylate, stearyl methacrylate (Octadecyl methacrylate), 1,1,1-trifluoro-2-propyl methacrylate, benzyl methacrylate, 2-ethylhexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate (dodecyl acrylate), tridecyl acrylate, hexadecyl Acrylate, stearyl acrylate (octadecyl acrylate , 1,1,1-fluoro-2
-Propyl acrylate, 2-naphthyl acrylate,
Vinyl benzoate, vinyl stearate, vinyl laurate, vinyl behenate, N-cyclohexylacrylamide, N, N-benzylacrylamide, N, N-dibutylacrylamide, N-laurylacrylamide, N-
Stearyl acrylamide, N-cyclohexyl methacrylamide, N, N-benzyl methacrylamide, N,
Although it can be used as a homopolymer of a monomer such as N-dibutyl methacrylamide, N-lauryl methacrylamide, N-stearyl methacrylamide, etc., it may be used as a copolymer with the polymerizable monomer described in the constitution (1). Is preferable because the glass transition point can be increased. Among the above monomers, the use of a monomer having an alkyl group or an aromatic group having a large number of carbon atoms is a preferable monomer for forming fine particles together with an organic silver salt. A polymerizable monomer having a log P of 2.0 or more is 5% of the total polymerizable monomer.
It is preferably from 80 to 80% by weight, more preferably from 20 to 60% by weight.

The glass transition temperature of the polymer of the water-dispersible organic silver salt-containing composite fine particles of the present invention is preferably from room temperature to 120 ° C., more preferably from 30 to 110 ° C.
Further, the temperature is preferably from 40 to 100 ° C. Log as above
In many cases, the homopolymer of a monomer having a P of 2.0 or more has a low glass transition point, and when a layer is formed by drying after coating on a support, a combination of a copolymerized monomer is used to prevent fusion. Preferably, the transition point is high.

The crosslinkable monomer of the constitution (3) of the present invention comprises:
In the case where the composition (2) has a polymerizable monomer having a log P of 2.0 or more and a low glass transition point, it is preferable that the fine particles be a cross-linked polymer with a cross-linkable monomer so as not to be fused. Thus, the water-dispersible organic silver salt-containing composite fine particles are particularly preferable. After the water-dispersible organic silver salt-containing composite fine particles are coated on the support, it is possible to prevent fusion of the fine particles and to reduce the reactivity of the organic silver salt during heat development without any loss. Does not hinder the movement of silver salts. Examples of such a crosslinking monomer include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, butylene glycol dimethacrylate, polyethylene glycol dimethacrylate, dimethacrylate of bisphenol A, ethylene glycol diacrylate, propylene glycol diacrylate, butylene glycol diacrylate, Polyethylene glycol diacrylate, diacrylate of bisphenol A,
N, N'-ethylenediaminediacrylamide, N,
N'-dimethylethylenediamine-N, N'-diacrylamide, bisacryloylurea, N, N'-ethylenediaminedimethacrylamide, N, N'-dimethylethylenediamine-N, N'-dimethacrylamide, bismethacryloylurea, divinyl Benzene and the like can be mentioned.

Further, a hydrophilic polymerizable monomer component may be included in a part of the copolymer in order to improve the dispersibility so as not to impair the hydrophobicity of the polymer of the present invention. Examples of the hydrophilic polymerizable monomer include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, acrylamide, methylacrylamide, and ethyl. Acrylamide, propyl acrylamide, butyl acrylamide, methacrylamide, methyl methacrylamide, ethyl methacrylamide, propyl methacrylamide, butyl methacrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N, N-dimethylmethacrylamide, N , N-diethyl methacrylamide, hydroxymethyl acrylamide, hydroxymethyl methacryl Bromide, methoxy-ethyl acrylamide,
Dimethylaminoethylacrylamide, diacetoneacrylamide, methoxyethylmethacrylamide, dimethylaminoethylmethacrylamide, diacetonemethacrylamide, N-vinylpyrrolidone, N-vinyloxazolidone, styrenesulfonic acid and salts thereof, acrylic acid and salts thereof, methacrylic acid And salts thereof, sulfopropylacrylamide salts, sulfopropylmethacrylamide salts, maleic anhydride and salts thereof, itaconic acid, polyethylene oxide esters of acrylic acid, and polyethylene oxide esters of methacrylic acid.

The ratio of the amount of the organic silver salt to the amount of the monomer is preferably 0.5 to 10 parts by weight of the polymerizable monomer per 1 part by weight of the organic silver salt. The ratio of the total amount of the organic silver salt and the polymerizable monomer to water is 0.05 to 0.4 parts by weight per 1 part by weight of water.

A preparation example of the aqueous dispersible organic silver salt composite fine particles of the present invention will be described.

[Preparation Example of Organic Silver Salt] 40 g of behenic acid, 7.3 g of stearic acid and 500 ml of water were added at 90 ° C. for 15 minutes.
Stir for 1 minute, add 187 ml of 1N NaOH over 15 minutes, add 61 ml of 1N nitric acid aqueous solution and add
The temperature dropped. Next, 124 ml of a 1N silver nitrate aqueous solution was added over 2 minutes, and the mixture was stirred as it was for 30 minutes. Thereafter, the solid content was separated by suction filtration, and the solid content was further washed with water and dried.

[Preparation of Aqueous Dispersible Organic Silver Salt Composite Fine Particles (FG-1)] 10 g of sodium diethylhexylsulfosuccinate was dissolved in 252 g of distilled water, and 36.4 g of the above-mentioned organic silver salt was added thereto while stirring. An ultrasonic element was introduced into the container and dispersed. 5.5 g of methyl methacrylate (MMA), 5.0 g of ethylene glycol dimethacrylate (EGDMA), 6.0 g of stearyl methacrylate (SMA), 0.6 g of hexadecane,
2'-azobis (2,4-dimethylvaleronitrile)
0.9 g of the mixture was added and further dispersed ultrasonically. 25 g of a 10% by weight aqueous solution of polyvinylpyrrolidone was added to 50 g of the dispersion, and the mixture was stirred while introducing nitrogen. The resulting dispersion was transferred to a 1-liter three-necked flask equipped with a thermometer, a nitrogen inlet tube, and a stirrer. 53 with stirring under a stream of nitrogen
A polymerization reaction was carried out at 15 ° C. for 15 hours to obtain aqueous dispersible organic silver salt composite fine particles (solid content: 19.9% by weight). The residual monomer amount in the obtained dispersion was less than 1%. The average particle size of the aqueous dispersible organic silver salt composite fine particles was 190 nm.

[Preparation of Aqueous Dispersible Organic Silver Salt Composite Fine Particles (FG-8)] 8 g of sodium dodecylbenzenesulfonate and 25 g of a 10% by weight aqueous solution of gelatin were dissolved in 152 parts of distilled water.
g), 36.4 g of the above-mentioned organic silver salt was added thereto, and the mixture was stirred and dispersed by ultrasonic waves to obtain an organic silver salt mixture. On the other hand, a 1-liter four-necked flask equipped with a thermometer, a nitrogen inlet tube, an ultrasonic element, and a monomer inlet funnel was prepared, and 0.5 g of potassium persulfate and 100 g of pure water in which 0.5 g of sodium acid sulfite was dissolved. And the organic silver salt mixture was added with stirring. The reaction vessel was heated to 30 ° C., and the dispersion was sufficiently performed by stirring and the ultrasonic element, and 4.0 g of styrene (St) and n-butyl acrylate (BA) were added thereto.
4.0 g, stearyl methacrylate (SMA) 6.0
g, and ethylene glycol dimethacrylate (EGD
MA) The polymerization reaction was carried out while mixing and dropping 2.5 g. After 6 hours, the polymerization was terminated by cooling to 20 ° C.
Aqueous dispersible organic silver salt composite fine particles were obtained (solid content: 19.9).
weight%). The amount of residual monomer in the obtained dispersion is 0.5
%Met. The average particle size of the aqueous dispersible organic silver salt composite fine particles was 550 nm.

The other aqueous dispersible organic silver salt composite fine particles FG-2 to 7 were prepared in the same manner as in FG-1. Table 1 shows the composition and the like.

[0058]

[Table 1]

Here, the symbols in the table are as follows.

MMA: methyl methacrylate SMA: stearyl methacrylate EGDMA: ethylene glycol dimethacrylate GMA: glycidyl methacrylate t-BMA: t-butyl methacrylate BA: butyl acrylate LMA: lauryl methacrylate CHMA: cyclohexyl methacrylate i-NA: isononyl acrylate St: Styrene PVP: polyvinylpyrrolidone.

<< Preparation of Organic Silver Salt Solid Dispersion KA-1 >> 10 g of sodium diethylhexylsulfosuccinate was dissolved in 252 g of distilled water, and 36.4 g of the above organic silver salt was added thereto.
, And introduce ultrasonic blocking into the container while stirring,
Dispersed.

Next, the reducing agent will be described.

The reducing agent used in the present invention is a compound which plays a role of reducing the silver source of the organic silver salt in a silver halide photographic light-sensitive material for thermal development. U.S. Pat. Nos. 3,770,448 and 3,7
No. 73,512 and 3,593,863, and RD17029 and 29996, and the following are mentioned.

Aminohydroxycycloalkenones (eg, 2-hydroxy-3-piperidino-2-cyclohexenone); aminoreductones esters (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents , N-hydroxyurea derivatives (eg, Np-methylphenyl-N-hydroxyurea), hydrazones of aldehydes or ketones (eg, anthracenaldehyde phenylhydrazone), phosphoamide phenols, phosphamide anilines, polyhydroxy Benzenes (e.g., hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5-dihydroxy-phenyl)
Methyl sulfone), sulfhydroxamic acids (eg,
Benzenesulfhydroxamic acid), sulfamidoanilines (eg, 4- (N-methanesulfamide) aniline), 2-tetrazolylthiohydroquinones (eg,
2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone), tetrahydroquinoxalines (eg, 1,2,3,4-tetrahydroquinoxaline),
Amido oximes, azines, combinations of aliphatic carboxylic acid aryl hydrazides and ascorbic acid, combinations of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine, hydroxanoic acids, combinations of gins and sulfoamide phenols, α -Cyanophenylacetic acid derivatives, combinations of bis-β-naphthol and 1,3-dihydroxybenzene derivatives, 5-pyrazolones, sulfamidophenol reducing agents, 2-phenylindane-1,3-dione, chromans, 1,4 -Dihydropyridines (eg, 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine), bisphenols (eg, bis (2-
Hydroxy-3-t-butyl-5-methylphenyl) methane, bis (6-hydroxy-m-tri) mesitol, 2,2-bis (4-hydroxy-
3-methylphenyl) propane, 4,4-ethylidene-
Bis (2-t-butyl-6-methylphenol), ultraviolet-sensitive ascorbic acid derivatives, hindered phenols, 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).

[0065]

Embedded image

In the formula, R is a hydrogen atom or a group having 1 carbon atom.
10 alkyl group (e.g., -C ₄ H _9, 2,4,4-
R ′ and R ″ represent an alkyl group having 1 to 5 carbon atoms (eg, 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.

[0068]

Embedded image

[0069]

Embedded image

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

In the constitution (4) of the present invention, the reducing agent is contained in a resin to form water-dispersible reducing agent-containing composite fine particles, and the reducing agent and the water-insoluble resin are dissolved in an organic solvent. Alternatively, a reducing agent is added to and dissolved in an organic solvent solution of the resin, and the resultant is added to an aqueous solution containing a surfactant and / or a water-soluble polymer having surfactant, and is highly dispersed. It is obtained by removing by evaporation or the like.

In the present invention, the resin containing a reducing agent is a water-insoluble resin, for example, a polyvinyl acetal resin, a polyvinyl butyral resin, a polyester resin, a cellulose ester resin, a polyurethane resin, a styrene-butadiene resin, a styrene resin. Examples thereof include an acrylonitrile resin, a vinyl acetate resin, a phenoxy resin, a vinylidene chloride resin, and an acrylic resin, and a resin having a property of softening when heat is applied during development is preferable.

A mixed solution is prepared by adding a reducing agent to a solution obtained by dissolving the water-insoluble resin in an organic solvent. Examples of the organic solvent usable for this purpose include acetone, methyl ethyl ketone, diethyl ketone, methyl butyl ketone, and cyclohexanone. , Methyl acetate, ethyl acetate, propyl acetate,
Amyl acetate, toluene, benzyl alcohol, methyl benzoate, ethyl benzoate, methylene chloride, ethyl chloride, propyl chloride, ethylene chloride, dioxane, cyclohexane, cyclohexanol, 2-pyrrolidone, acetamide, N, N-dimethylformamide, N, Examples thereof include N-dimethylacetamide, dimethylsulfoxide, and tetrahydrofuran. Two or more N-dimethylacetamides may be used in combination.

The surfactant and the water-soluble polymer having surfactant are omitted because they are the same as those described in the constitution (1).

A method for preparing the water-dispersible reducing agent-containing composite fine particles of the constitution (4) of the present invention will be described.

[Preparation of water-dispersible reducing agent-containing composite fine particles R
G-1] 92 g of butyral resin in 405 g of ethyl acetate
And 98 g of 1,1-bis (hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane were dissolved and added to 1800 g of a 4% by weight gelatin solution containing 12 g of sodium dioctylsulfonesuccinate. Then, while dispersing by high-speed stirring, the pressure was reduced to remove ethyl acetate to obtain water-dispersible reducing agent-containing composite fine particles.

<< Preparation of Reducing Agent Solid Dispersion KR-1 >> 10 g of sodium diethylhexylsulfosuccinate was dissolved in 252 g of distilled water, and 1,1-bis (hydroxy-3,
Then, 98 g of (5-dimethylphenyl) -3,5,5-trimethylhexane was added, and the mixture was dispersed by introducing ultrasonic blocking into the vessel with stirring.

The water-dispersible organic silver salt-containing composite fine particles of the constitution (5) of the present invention are dispersed by being contained in a polymer obtained by polymerizing the organic silver salt formed by the method of the constitutions (1) to (3). It is in the form of fine particles. As described above, the water-dispersible organic silver salt-containing composite fine particles are particles having an average particle size of 3 μm or less, preferably 500 nm or less, and may be used as powdery fine particles taken out from the dispersion. May be used in a dispersed state.

The water-dispersible reducing agent-containing composite fine particles of the constitution (6) of the present invention are particles in which the reducing agent formed by the method of the constitution (4) is contained and dispersed in a resin. . The composite fine particles containing a water-dispersible reducing agent have an average particle size of 5
μm or less, preferably 500 nm or less particles,
It may be used as powdery fine particles taken out of the dispersion, or may be used in a state of being dispersed in water.

The constitution (7) of the present invention is a silver halide photographic light-sensitive material for thermal development using the water-dispersible organic silver salt-containing composite fine particles of the constitution (5) as an organic silver salt. The water-dispersible organic silver salt-containing composite fine particles of the present invention in a silver halide photographic light-sensitive material for thermal development are contained in a layer containing silver halide together with a reducing agent for reducing this organic silver salt. Although organic silver salts used in conventional silver halide photographic materials for thermal development are dispersed in the binder forming the photosensitive layer, silver halide particles, reducing agents, or other It is in a state where it can partially come into contact with the additive, and its storage stability is poor. On the other hand, in the water-dispersible organic silver salt-containing composite fine particles of the present invention, the organic silver salt forms fine particles together with the hydrophobic polymer, so that the organic silver salt hardly comes into contact with the silver halide particles and the reducing agent, and therefore the storage stability is low. It is expected to be very stable.

The constitution (8) of the present invention is a silver halide photographic light-sensitive material for thermal development using the water-dispersible reducing agent-containing composite fine particles of the constitution (6) as a reducing agent. The water-dispersible reducing agent-containing composite fine particles of the present invention in a silver halide photographic light-sensitive material for thermal development are contained in a layer containing silver halide together with an organic silver salt. Although the reducing agent used in conventional silver halide photographic light-sensitive materials for thermal development is dispersed in the binder forming the photosensitive layer, silver halide particles, organic silver salts, or other It is in a state where it can be partially in contact with the additive, and storage stability is likely to deteriorate. On the other hand, in the water-dispersible reducing agent-containing composite fine particles of the present invention, the reducing agent forms fine particles together with the hydrophobic polymer, and does not come into contact with silver halide particles or organic silver salts. Is considered to be very stable.

In the constitution (9) of the present invention, the water-dispersible organic silver salt-containing composite fine particles of the constitution (5) and the water-dispersible reducing agent-containing composite fine particles of (6) are used together as an organic silver salt and a reducing agent. It is a silver halide photographic material for thermal development. The water-dispersible organic silver salt-containing composite fine particles and the water-dispersible reducing agent-containing composite fine particles of the present invention in the silver halide photographic light-sensitive material for thermal development are both contained in a layer containing silver halide. Although the organic silver salt and the reducing agent used in the conventional silver halide photographic light-sensitive material for thermal development are both dispersed in the binder forming the photosensitive layer, the silver halide particles,
Organic silver, a reducing agent or other additives are in a state where they can partially come into contact with each other, and storage stability is likely to deteriorate. On the other hand, in the water-dispersible organic silver salt-containing composite fine particles and the water-dispersible reducing agent-containing composite fine particles of the present invention, the organic silver salt and the reducing agent are each separately formed into fine particles together with a hydrophobic polymer, Configuration (7) or Configuration (8) because silver halide grains, organic silver salts, reducing agents, etc. do not come in contact
Furthermore, it is considered that the storage stability is very stable.

In the constitution (7) of the present invention, a solid dispersion type reducing agent may be used, and a part of the water-dispersible organic silver salt-containing composite fine particles is replaced with a solid dispersion type organic silver salt. Is also good. In the constitution (8), the organic silver salt may be a solid dispersion type, or a part of the water-dispersible reducing agent-containing composite fine particles may be a solid dispersion type organic silver salt. However, any of them should be kept to the extent that storage stability is not deteriorated.

Further, in (9) of the present invention, a part of the water-dispersible organic silver salt-containing composite fine particles may be replaced by a solid dispersion type organic silver salt. In this case, all the reducing agents are water-dispersible. It is preferable to use reducing agent-containing composite fine particles. On the contrary, a part of the water-dispersible reducing agent-containing composite fine particles may be replaced with a solid-dispersion type reducing agent. In this case, it is preferable that all the organic silver salts are water-dispersible organic silver salt-containing composite fine particles. .

The hydrophobic polymer (or resin) used in the water-dispersible organic silver salt-containing composite fine particles or the water-dispersible reducing agent-containing composite fine particles of the present invention has a glass transition point in a temperature range of room temperature to 120 ° C. And preferably 40
Those having a glass transition point of -100 ° C are preferred. The present inventors believe that when the mobility of the hydrophobic polymer increases at a temperature equal to or higher than the glass transition point, silver ions are easily released and diffused.

Here, the layer containing the photosensitive silver halide grains and the silver halide according to the present invention will be described.

The silver halide grains in the present invention function as an optical sensor. The formation of silver halide is well known in the art and is described in RD 17029 (197
June, 2008), and U.S. Pat. No. 3,700,458. The grain size of the silver halide is preferably as small as possible, preferably 0.1 μm or less, more preferably 0.1 μm, for the purpose of suppressing white turbidity after image formation and for obtaining good image quality. 01 to 0.1 μm, especially 0.02 to 0.
It is preferably 08 μm. 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 of non-normal crystal tabular grains,
It means the diameter when converted into a circular image having the same area as the projected area of the main surface. If other normal crystals are good, for example, spherical particles,
In the case of rod-shaped grains or the like, the diameter means a sphere equivalent to the volume of silver halide grains. Further, the silver halide is preferably monodispersed. The monodispersion as used herein means that the degree of monodispersion determined by the following formula is 40% or less, and 30%
The following is preferred, and more preferably 0.1 to 20%.

Monodispersity = (standard deviation of particle size) / (average value of particle size) × 100 In the present invention, the silver halide particles have an average particle size of 0.1.
It is more preferable that the particle size is not more than μm and that the particles are monodisperse particles. When the particle size falls within this range, the granularity of the image is also improved.

The shape of the silver halide grains is not particularly limited, but the proportion occupied by the Miller index [100] plane is preferably high, and this proportion is 50% or more, and more preferably 7% or more.
It is preferably at least 0%, particularly preferably at least 80%. The ratio of the Miller index [100] plane is determined by the T.M. Tani, J .; Imaging Sci. , 29,
165 (1985).

Another preferred form of silver halide is tabular grains. The term “tabular grain” as used herein refers to a grain having an aspect ratio = (r / h) of 3 or more, where the square root of the projected area is a particle diameter r (μm) and the thickness in the vertical direction is h (μm). Among them, the aspect ratio is preferably 3 to 50. The particle size is preferably 0.1 μm or less, and more preferably 0.01 to 0.08 μm. These are described in U.S. Pat. Nos. 5,264,337, 5,314,798, and 5,320,958, and can easily obtain target tabular grains. In the present invention, when these tabular grains are used, 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
(Paul Montel, 1967);
F. Photographic Em by Duffin
ulsion Chemistry (The Foca
l Press, 1966); L. Zelik
Making and Coa by man et al
ting Photographic Emulsio
n (published by The Focal Press, 1964)
Can be prepared using the methods described in US Pat. That is, any of an acidic method, a neutral method, an ammonia method and the like may be used, and as a forming method for reacting a soluble silver salt and a soluble halogen salt, any one of a one-side mixing method, a double-mixing method, a combination thereof and the like is used. Is also good. Further, the silver halide may be added to the image forming layer by any method, and the silver halide is preferably arranged so as to be close to the reducible silver source. Further, the silver halide may be prepared by converting a part or all of silver in the organic silver salt by a reaction between the organic silver salt and a halogen ion into silver halide, or 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, silver halide is 0.75 to organic silver salt.
Preferably, it is contained in an amount of 30% by weight.

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, hexacoordinate 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, tellurocyanate, azide and 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.

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

The following are specific examples of transition metal complex ions, but the present invention is not limited to these.

[0097] 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 may be a metal complex or metal complex ions one type, the metal of the same kind of metal or different may be used alone or 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 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, it may be added in several divided portions, may be added uniformly 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. H10-208, it is also possible to make the particles have a distribution and contain them. Preferably, the particles can have a distribution inside.

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 in which an aqueous solution of a powder or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble silver salt solution or a water-soluble halide solution during grain formation, or 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 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 necessary 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 the 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 flocculation method, but in the present invention, it may or may not be desalted. .

The photosensitive silver halide grains in the present invention are preferably chemically sensitized. As a preferable chemical sensitization method, a sulfur sensitization method, a selenium sensitization method, and a tellurium sensitization method are well known in the art. Further, a noble metal sensitization method or a reduction sensitization method of a gold compound, platinum, palladium, iridium compound or the like can be used. As the compound preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds can be used, and the compounds described in JP-A-7-128768 can be used. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl)
Tellurides, bis (carbamoyl) tellurides, diacyltellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, compounds having a P = Te bond, tellurocarboxylates, Te-organyltellurocarboxylate , Di (poly) tellurides, tellurides, tellurols, telluroacetals,
Tellurosulfonates, compounds having a P-Te bond,
Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Compounds preferably used in the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, US Pat. No. 2,448,060, and British Patent 618,0
Compounds described in, for example, the specification of No. 61 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 performed by ripening the emulsion while keeping the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Also, reduction sensitization can be achieved by introducing a single addition portion of silver ions during grain formation.

The silver halide photographic light-sensitive material for thermal development of the present invention contains a large amount of silver halide particles, water-dispersible organic silver salt-containing composite fine particles, water-dispersible organic silver salt-containing composite fine particles, or other particles. The total amount of the silver halide and the dispersible organic silver salt-containing composite fine particles is 0.5 to 4.0 per m ² in terms of silver amount.
0 g, and the amount of silver halide relative to the total amount of silver is 50% or less by weight, preferably 25% or less.
Hereinafter, it is more preferably in the range of 0.1 to 15%.

Next, silver tone agents useful in the present invention will be described.

The heat-developable silver halide photographic light-sensitive material of the present invention advantageously contains, in addition to the above-mentioned components, an additive known as a toning agent for improving an image.
Examples of suitable toning agents are disclosed in RD 17029,
There are 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, hexaamminetrifluoroacetate of cobalt), mercaptans (eg, 3-mercapto-1, 2,4-triazole), N
-(Aminomethyl) aryldicarboximides (eg, N- (dimethylaminomethyl) phthalimide),
Combinations of blocked pyrazoles, isothiuronium derivatives and certain photobleaches (eg, N, N ')
-Hexamethylenebis (1-carbamoyl-3,5-dimethylpyrazole), 1,8- (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) benzothiazole ), Merocyanine dyes (for example,
3-ethyl-5-[(3-ethyl-2-benzothiazolinylidene) -1-methylethylidene] -2-thio-2,
4-oxazolidinedione), phthalazinone, phthalazinone derivatives or metal salts of these derivatives (e.g.,
(1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione), a combination of phthalazinone and a sulfinic acid derivative (for example, 6-chlorofuran) Tarazinone and sodium benzenesulfinate, or 8
-Methylphthalazinone and sodium p-tolylsulfinate), a combination of phthalazinone and phthalic acid, phthalazine (including adducts of phthalazine 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)
Quinazolinedione, benzoxazine or naphthoxazine derivative, benzoxazine-2,4-dione (for example, 1,3-benzoxazine-2,4-dione), pyrimidine and asymmetric-
Triazines (eg, 2,4-dihydroxypyrimidine) and tetraazapentalene derivatives (eg, 3,
6-dimercapto-1,4-diphenyl-1H, 4H-
2,3a, 5,6a-tetrazapentalene) and the like. Preferred toning agents are phthalazine and phthalazone.

In the present invention, a mercapto compound, a disulfide compound, and a thione compound are contained in order to control development by suppressing or accelerating development, to improve spectral sensitization efficiency, or to improve storage stability before and after development. I can do it.

When a mercapto compound is used in the silver halide photographic light-sensitive material for thermal development of the present invention, any structure may be used as long as it is a mercapto compound, but it is represented by Ar-SM or Ar-SS-Ar. Are preferred.
Wherein M is a hydrogen atom or an alkali metal atom;
r is a heteroaromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium 7 atoms. Preferred heteroaromatic rings include benzimidazole, naphthymidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole,
Benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine,
Pyridine, purine, quinoline or quinazolinone. This heteroaromatic ring is, for example, halogen (eg, B
r and Cl), hydroxy, amino, carboxy, alkyl (for example, having 1 or more carbon atoms, preferably having 1 to 4 carbon atoms), and alkoxy (for example,
May have a substituent group selected from those having 1 or more carbon atoms, preferably 1 to 4 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, 2-mercaptoquinoline, 8-
Mercaptopurine, 2,3,5,6-tetrachloro-4
-Pyridinethiol, 4-hydroxy-2-mercaptopyrimidine, 2-mercapto-4-phenyloxazole, and the like, but the invention is not limited thereto.

The silver halide photographic light-sensitive material for thermal development of the present invention may contain an antifoggant. What is known as the most effective antifoggant is mercury ion. The use of mercury compounds as antifoggants in light-sensitive materials is described, for example, in US Pat. No. 3,589,9.
No. 03. However, mercury compounds are environmentally unfriendly. Non-mercury antifoggants include, for example, U.S. Pat. Nos. 4,546,075 and 4,452.
Preferred are antifoggants as disclosed in JP-A-885-885 and JP-A-59-57234.

Particularly preferred non-mercury antifoggants are disclosed in US Pat. Nos. 3,874,946 and 4,756,99.
Compound as disclosed in the specification of No. 9, -C
_{1 represented by} (X ₁ ) (X ₂ ) (X ₃ ), wherein X ₁ and X ₂ are halogen, and X ₃ is hydrogen or halogen.
It is a heterocyclic compound having at least two substituents. Examples of suitable antifoggants include JP-A-9-288328.
Compounds described in Paragraph Nos. [0030] to [0036] of the publication are preferably used. Another example of the preferred antifoggant is described in JP-A-9-905.
No. 50, paragraphs [0062] to [0063]. Still other suitable antifoggants are described in U.S. Pat. Nos. 5,028,523 and British Patent Application Nos. 922138383.4 and 9300147.7.
And No. 93111790.1.

The silver halide photographic light-sensitive material for heat development of the present invention includes, for example, JP-A-63-159814 and JP-A-60-1984.
140335, 63-231437, 63-2
Nos. 59651, 63-304242, and 63-
No. 15245, U.S. Pat. No. 4,639,414,
Nos. 4,740,455 and 4,741,966
No. 4,751,175, and No. 4,835,
Sensitizing dyes described in JP-A-0996 can be used. Sensitizing dyes useful in the present invention include, for example, RD17643IV-
Section A (December 23, 1978), Section 1831X (1
Aug. 978, p. 437). In particular, sensitizing dyes having 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
The compounds described in JP-A Nos. 4409 and 9-80679 are preferably used.

In addition, various additives may be contained in the silver halide photographic light-sensitive material for thermal development. It may be added to any of the photosensitive layer, the non-photosensitive layer and other forming layers. In the silver halide photographic light-sensitive material for thermal development of the present invention, for example, a surfactant, an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, a coating aid, and the like may be used. These additives and the other additives mentioned above are RD17029 (19
The compounds described in June, 1978, pages 9 to 15) can be preferably used.

In the constitution (10) of the present invention, the following water-soluble polymer and / or water-dispersible polymer particles other than the above-mentioned composite fine particles are used as the binder, and are useful for the flexibility and adhesion of the binder. Thus, the addition of these particles is preferred.

In the constitutions (11) and (12) of the present invention, since the silver halide photographic light-sensitive material for thermal development is an aqueous coating solution, the silver halide particles, the composite fine particles, and the composite fine particles containing a water-dispersible reducing agent are used. , Enhances the dispersion stability and applicability of the coating solution containing other substances dispersed therein,
It is added to increase the film strength after the formation of the photosensitive layer and to separate these composite fine particles in the layer.

As a binder of a water-soluble polymer useful in the present invention, gelatin and other water-soluble polymers are also preferably used. The water-soluble polymer is preferably contained in an amount of 5% by weight or more with respect to all the binders, and the water-soluble polymer is preferably gelatin (the present invention (11) and (12)).

Examples of the water-soluble polymer include gelatin, gelatin derivatives, graft polymers of gelatin and other polymers, proteins such as albumin and casein, hydroxyethylcellulose, carboxymethylcellulose, cellulose sulfate, sodium alginate and the like. Cellulose or analog derivatives, dextrins,
Single or copolymers of sugar derivatives such as dextran or dextran sulfate, polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, etc. And synthetic water-soluble polymers such as As the gelatin, lime-processed gelatin, acid-processed gelatin, or a combination thereof, a hydrolyzate of gelatin, an enzymatic decomposition product of gelatin, and the like can be used.
A plurality of the above water-soluble polymer binders may be used in combination.

In the present invention, in order to increase the speed of thermal development, the amount of the binder in the photosensitive layer is 1.0 to 15 g / m ^2.
It is preferable that More preferably, 1.7 to 8 g /
m ² .

The water-dispersible polymer particles of the constitution (10) of the present invention may be made of a resin, for example, an acrylic resin, a polyester resin, a rubber, a polyvinyl acetate, a polyvinyl acetal, a cellulose ester, a polyurethane, a polychlorinated resin. What disperse | distributed vinyls, polyvinylidene chlorides, etc. in water, or the polymer particle which carried out the emulsion polymerization of the said polymerizable monomer may be used.

The heat-developable silver halide photographic light-sensitive material of the present invention has at least one light-sensitive layer on a support. The photosensitive layer may be composed of a plurality of layers, and in order to adjust the gradation, the sensitivity is adjusted so that the upper layer is a high sensitivity layer, the lower layer is a low sensitivity layer, or the upper layer is a low sensitivity layer, and the lower layer is a high sensitivity layer. May be.

The silver halide photographic light-sensitive material for thermal development according to the present invention comprises at least one photosensitive layer on a support in addition to the photosensitive layer.
A non-photosensitive layer of a layer may be formed. To control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer on the same side as the photosensitive layer and / or an antihalation dye layer, a so-called back layer, may be formed on the opposite side. Dyes or pigments may be included in the layer. As the dye to be used, any compound may be used as long as it has a desired absorption in a desired wavelength range. Examples thereof include JP-A-59-6481 and JP-A-59-182436, and U.S. Pat. No. 4,271,263. No. 4,594,31
No. 2, European Patent Publication Nos. 533,008 and 652,
473, JP-A-2-216140, 4-3
No. 48339, No. 7-191432, No. 7-3018
Compounds described in JP-A-90-90 and the like are preferably used.

It is preferable that these non-photosensitive layers contain the binder, slipping agent and matting agent described above.
It may contain the slip agent described in Japanese Patent Application No. 10-184101.

The support useful in the present invention is a plastic film having heat resistance so as to prevent deformation of an image due to deterioration of the support itself and flatness in a heat development process. For example,
Polyester film, polycarbonate film, polyimide film, polyethersulfone film, nylon film, cellulose triacetate film,
Syndiotactic polystyrene film and the like can be mentioned.

As the polyester film, commercially available polyethylene terephthalate or polyethylene-2,6-naphthalate is preferably used. In addition to these, terephthalic acid, naphthalene-2,6-dicarboxylic acid, isophthalic acid, butylene dicarboxylic acid, 5-sodium sulfoisophthalic acid, adipic acid and the like as acid components, and ethylene glycol, propylene glycol, butanediol as glycol components And a modified polyester with cyclohexanedimethanol or the like. Modified polyester component is 10% of all polyester
% Or less, and the others are preferably polyethylene terephthalate or polyethylene-2,6-naphthalate.

The syndiotactic polystyrene film is a polystyrene having steric regularity unlike ordinary polystyrene (atactic polystyrene). The regular stereoregular structure part of SPS is called a racemo chain, and it is preferable that there are more regular parts such as two, three, five or more. In the present invention, the racemo chain is 2 85% or more for 3 chains, 75% or more for 5 chains, 50% or more for 5 chains, 3
It is preferably 0% or more. The polymerization of SPS can be carried out according to the method described in JP-A-3-131843.

A heat-treated plastic film can also be used. 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 by 35 ° C. or more, More preferably, heating is performed at a temperature higher than 40 ° C.

As the above-mentioned preferred supports, polyethylene terephthalate film, polyethylene-2,6-
A plastic containing a naphthalate film and a styrenic polymer having a syndiotactic structure.

The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm.

As the method of forming a film of a support and the method of producing an undercoat on the support according to the present invention, known methods can be used.
It is preferable to use the method described in [30] to [0070].

In the present invention, an antistatic layer is preferably provided on a support. As the antistatic layer, a conductive compound such as a metal oxide and / or a conductive polymer can be included in the constituent layer. The antistatic layer may be contained in any layer on the support, but it may be a layer serving as both an undercoat layer and an antistatic layer, or an undercoat layer and a back layer, or a photosensitive layer and an undercoat layer. It is also preferable to provide between them. The conductive compounds described in U.S. Pat. No. 5,244,773, columns 14 to 20, can be preferably used.

When providing the undercoat layer, the support may be subjected to a corona discharge treatment, a glow discharge treatment, a discharge plasma in gas treatment, an ultraviolet irradiation treatment, or the like. Further, a corona discharge, a glow discharge, an ultraviolet ray, or the like may be applied to the applied undercoat layer to provide a photosensitive layer or the like.

In the present invention, a matting agent may be contained in any one of the layers on the photosensitive layer side. In order to prevent the image from being damaged after the heat development, the surface of the silver halide photographic light-sensitive material for heat development is used. It is preferable to provide a matting agent on the surface protective layer, and it is preferable to add a matting agent to the surface protective layer. 0.5 to 30% by weight of the matting agent with respect to all binders on the emulsion layer side
It is preferred to contain.

The matting agent useful 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, and British Patent No. 1,173,181. The described alkaline earth metals or carbonates such as cadmium and zinc can be used as the matting agent. Examples of the organic substance include starch described in US Pat. No. 2,322,037, Belgian Patent No. 625,451, and British Patent No. 981,198.
Derivatives described in Japanese Patent Publication No. 44-364.
No. 3, No. 3,079,257, polystyrene or polymethacrylate described in Swiss Patent No. 330,158.
And organic matting agents such as polycarbonate described in U.S. Pat. No. 3,022,169 and the like.

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 useful in the present invention has an average particle size of 0.5 μm to 1 μm.
0 μm, more preferably 1.0 μm
m 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 method of adding the matting agent according to the present invention may be a method of applying the matting agent by dispersing it in a coating solution in advance, or applying A method of spraying a matting agent after the application of the liquid 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.

In the silver halide photographic light-sensitive material for heat development of the present invention, the silver halide emulsion layer and other hydrophilic colloid layers can be coated on a support or other layers by various coating methods. For the coating, a dip coating method, a roller coating method, a curtain coating method, an extrusion coating method, a slide hopper method, or the like can be used. For details, RD No. 1
Volume 76, pages 27-28, "Coating Process"
dures "section.

The present invention is characterized in that an image is formed by thermally developing a silver halide photographic light-sensitive material for thermal development at 80 to 140 ° C., and no fixing is performed. Therefore, the silver halide and the organic silver salt remaining in the unexposed area remain in the photosensitive material without being removed. After the heat development, the optical transmission density of the silver halide photographic light-sensitive material for heat development including a support at 400 nm other than the image is preferably 0.2 or less. A more preferable value of the optical transmission density is 0.02 or more and 0.2 or less.

Hereinafter, the present invention will be described in detail with reference to Examples, but embodiments of the present invention are not limited thereto.

[0139]

EXAMPLES Examples 1 to 12 and Comparative Examples 1 and 2 [Preparation of Subbing Layers A-1 and B-1] Biaxial 175 μm thick blue colored to an optical density of 0.17 Stretched and heat-fixed polyethylene terephthalate film on both sides by applying a corona discharge of 8 W / m ² · min.
On one surface, the following undercoat layer coating solution a-1 was dried to a thickness of 0.8.
After coating so as to have a thickness of μm, drying was performed to obtain an undercoat layer A-1. Further, the following undercoat layer coating solution b-1 was applied to the opposite surface so that the dry film thickness was 0.8 μm, and then dried to form an undercoat layer B
It was set to -1.

<< Undercoat Layer Coating Solution a-1 >> Butyl acrylate / t-butyl acrylate / styrene / 2-hydroxyethyl acrylate (30/20/25/25 by weight ratio) copolymer latex solution (solid content) (30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethyleneurea) 0.8 g Finished to 1 liter with water.

<< Preparation of Subbing Layer Coating Solution b-1 >> Butyl acrylate / styrene / glycidyl acrylate (40/20/40 by weight ratio) copolymer latex liquid (solid content 30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Make up to 1 l with water.

A corona discharge having a strength of 8 W / m ² · min was applied on the undercoat layer A-1, and a coating liquid a-2 for undercoat layer described below was applied at 10 ml / m ² and dried at 100 ° C. for 1 minute. Lower layer upper layer A
-2.

<< Preparation of Lower Coating Upper Layer Coating Solution a-2 >> Gelatin 10 g (C-1) 0.2 g (C-2) 0.2 g (C-3) 0.1 g (CF) 0.1 g Silica Particles (average particle size: 3 μm) 0.1 g Finish to 1 liter with water.

[0144]

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[Preparation of Antistatic Layer B-2] Undercoat Layer B
-1 is subjected to a corona discharge with an intensity of 8 W / m ² · min,
The antistatic layer coating solution b-2 was applied using a combination of a roll coater and a wire bar so that the dry film thickness was 0.8 μm, and dried at 100 ° C. for 1 minute to obtain an antistatic layer B-2.

<< Preparation of Conductive Composition 1 >> (A) 2-acetoacetoxyethyl methacrylate / acrylic acid / butyl acrylate (40/5/55, weight ratio): Polymer particles emulsion-polymerized using the agent (S-2) (B) 4-sulfostyrene / maleic anhydride (75/2)
(5% by weight) Hydrolyzate due to aqueous solubility of caustic soda in the copolymer (sulfonic acid and carboxylic acid are all sodium salts) (A) and (B) are mixed and stirred, and then heated to form conductive composition 1. Produced.

<< Preparation of Antistatic Layer Coating Solution b-2 >> Conductive Composition 1 (solid content) 90 mg / m ² silica particles (average particle size 3 μm) 0.1 g / m ² (C-1) 1 g / m ² (C-4) Finish to 1.5 l with 12 g / m ² water.

[0148]

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[0149]

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[Preparation of silver halide photographic light-sensitive material for thermal development] The support thus prepared was provided with the following image forming layer.

The image forming layer was coated so that the coating amount of the following emulsion layer coating solution was 2.1 g / m ² and the back layer was such that the gelatin of the following back layer coating solution was 2 g / m ^2. did. A protective layer was applied on the image forming layer and the back layer so that each material had the following coating amount.

<< Preparation of Silver Halide Emulsion A >> Water 700m
7.5 g of inert gelatin (phthalated gelatin 2
2 g) and 10 mg of potassium bromide were dissolved at a temperature of 35.
After adjusting the pH and the pH to 3.0, 370 ml of an aqueous solution containing 74 g of silver nitrate, an aqueous solution containing potassium bromide and potassium iodide in a molar ratio of (98/2) and [Ir (NO) C
l _5] a 1 × 10 ^-6 mol and 1 × 10 ^-4 mol per mol of silver rhodium chloride salt per mole of silver salt, PAG7.
While maintaining at 7, the addition was performed by the controlled double jet method. Thereafter, 4-hydroxy-6-methyl-1,3,3
a, 7-Tetrazaindene was added and the pH was adjusted to 5 with NaOH.
Adjusted to an average particle size of 0.06 μm and a monodispersity of 10
% Projection diameter area variation coefficient 8%, [100] face ratio 8
7% of cubic silver iodobromide grains 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 to obtain a silver halide emulsion A. Further, chemical sensitization was performed with chloroauric acid and inorganic sulfur.

<< Preparation of Emulsion Layer Coating Solution >> The following materials were added to a gelatin solution prepared by dissolving gelatin as a binder in water to prepare an emulsion layer coating solution. As organic silver salts,
The water-dispersible organic silver salt-containing composite fine particles and the solid-dispersed organic silver salt particles are used from among the organic silver salts described in Table 2, and the water-dispersible reducing agent-containing composite fine particles and the solid-dispersed reducing agent particles are used as a reducing agent. Examples 1 to 1 with different binders
2 and Comparative Examples 1 and 2 are shown in Table 2 below.

The binder is gelatin or gelatin 1
/ 2 (weight ratio) was used as a solid mixture, and the weight was replaced with a water-dispersible polymer (LX-1, LX-2, LX-3). In Comparative Example 2, the total amount was LX-3. Here, LX-2: 5-sodium dimethyl sulfoisophthalate / dimethyl isophthalate / dimethyl adipate / dimethyl terephthalate (5/10/10/75 weight ratio) and ethylene glycol / polyethylene glycol (95/5 weight ratio) LX-3: aqueous dispersion of polyvinyl butyral (solid content 3% by weight)
0% by weight).

Binder 72 g Pure water 140 g Organic silver salt (types listed in Table 2) Equivalent to 1 mole of silver = 6173 g Silver halide emulsion A 0.1 mole equivalent of silver Reducing agent (Types shown in Table 2) 2000 g Tetrachlorophthale Acid 5g Phthalazine 9.2g Tribromomethylphenylsulfone 12g 4-Methylphthalic acid 7g <Coating of coating solution for back layer><< Preparation of colorant dispersion >> Ethyl acetate 35g Compound 1 2.5g Compound 2 7.5g Polyvinyl alcohol (10 (Wt% aqueous solution) 50 g First, the compound 2 was stirred to form a solution. The polyvinyl alcohol was added thereto, and the mixture was stirred with a homogenizer for 5 minutes. Thereafter, the solvent was volatilized by depressurizing the ethyl acetate, and finally diluted to 1 liter with water to prepare a color former dispersion.

<< Preparation of Back Layer Coating Solution >> Water 500 g Gelatin 30 g 2-acetoacetoxyethyl methacrylate / butyl acrylate / styrene (40/20/40, by weight) Active methylene group-containing latex (Lx-1) (solid content 20 g%) 50 g Color former dispersion (above) 50 g Compound 3 20 g Silica (micron spherical particles having an average particle diameter of 10) 1.5 g

[0157]

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<< Preparation of Coating Solution for Protective Layer and Formation of Protective Layer >> The following protective layer was prepared, coated on the emulsion layer and the back layer in the following coating amount (one side), and dried to obtain a sample. .

Gelatin 0.4 g / m ² polymethyl methacrylate (mat agent area average particle size 7.0 μm) 50 mg / m ² formaldehyde 10 mg / m ² 2,4-dichloro-6-hydroxy-1,3,5-triazine sodium salt 5 mg / m ² bis - vinylsulfonyl methyl ether 18 mg / m ² active methylene group-containing latex (Lx-1) 0.1g / m 2 polyacrylamide (average molecular weight 10000) 0.05g / m ² of sodium polyacrylate 20mg / M ² polysiloxane (S1) 20 mg / m ² (C-1) 12 mg / m ² compound (J) 2 mg / m ² compound (S-1) 7 mg / m ² compound (K) 15 mg / m ² compound (O ) 50 mg / m ² surfactant (S-2) 5 mg / m ² C ₉ F ₁₉ O (CH ₂ CH ₂ O) ₁₁ H 3 mg / m ² C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ CH ₂ O) ₁₅ H 2 mg / m ² C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ CH ₂ O) ₄ (CH ₂ ) ₄ SO ₃ Na 1 mg / m ² Hardener (B) 1.5 mg / m ²

[0160]

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[0161]

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As shown in Table 2, a sample was prepared by using a solid dispersion as the organic silver salt and the reducing agent in the section of preparation of the emulsion coating solution, halving the amount of gelatin, and replacing the binder with another.

<< Exposure and Development Processing >> The silver halide photographic light-sensitive material for thermal development prepared as described above was exposed with an imager having a semiconductor laser of 810 nm. Then, at 110 ° C. for 15 minutes using an automatic developing machine having a heat drum.
Second heat development processing. At that time, exposure and development were performed at 23 ° C and 5 ° C.
The test was performed in a room conditioned at 0% RH.

(Evaluation of photographic properties at normal temperature and normal humidity) The optical density of the obtained image was measured, and the minimum density (Dmin) was obtained.

(Evaluation of Photographic Properties at High Humidity) Three samples were stacked so that the surface of the photosensitive layer and the surface of the back layer were overlapped.
It was left in a room conditioned at 0 ° C. and 80% RH for 10 days.
Next, these samples were exposed and developed in an atmosphere of 30 ° C. and 80% RH, and the minimum density (Dmin) was measured.

(Evaluation of Moisture Resistance) The moisture resistance of the sample of the prepared silver halide photographic light-sensitive material for thermal development was evaluated by adjusting the Dmin
The difference between the Dmin value and the Dmin value of the sample measured at normal temperature and normal humidity, exposed, developed, and measured was evaluated as moisture resistance.
It was shown to.

[0167]

[Table 2]

(Results) The storage fog of a silver halide photographic light-sensitive material for thermal development using the water-dispersible organic silver salt-containing composite fine particles of the present invention and the water-dispersible reducing agent-containing composite fine particles in a high humidity atmosphere is extremely low. Turned out to be small.

[0169]

According to the present invention, a silver halide photographic light-sensitive material for thermal development, which has been coated and prepared in a conventional organic solvent system, can be coated and prepared in an aqueous system, which is advantageous in terms of environment, safety, and manufacturing cost. And can suppress the increase in fog of the conventional silver halide photographic light-sensitive material for thermal development during storage in a high-humidity atmosphere, and can provide an epoch-making silver halide photographic photosensitive material for thermal development. .

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H123 AB00 AB03 AB23 AB28 BA00 BA14 BC00 BC12 CB00 CB03 4J011 PA29 PA40 PA44 PA45 PA85 PB40 PC06

Claims (12)

[Claims] 1. A method for producing composite fine particles containing water-dispersible organic silver salt, comprising forming a composite fine particle by polymerizing a polymerizable monomer in an aqueous solution containing an organic silver salt. 2. The polymerizable monomer has a log P ≧ 2.0.
The method for producing water-dispersible organic silver salt-containing composite fine particles according to claim 1, wherein the fine particles have a value of: 3. The method for producing water-dispersible organic silver salt-containing composite fine particles according to claim 1, wherein the polymerizable monomer contains a crosslinkable monomer. 4. A method for producing composite fine particles containing a water-dispersible reducing agent, comprising adding a reducing agent to a resin and forming the composite fine particles in an aqueous liquid. 5. Composite fine particles containing a water-dispersible organic silver salt, formed by the method according to claim 1. Description: 6. A water-dispersible reducing agent-containing composite fine particle formed by the method according to claim 4. Description: 7. A heat-developable silver halide photographic material having a photosensitive layer containing a photosensitive silver halide on a support, and containing an organic silver salt and a reducing agent for the organic silver salt,
A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible organic silver salt-containing composite fine particles according to claim 5. 8. A heat-developable silver halide photographic material having a photosensitive layer containing a photosensitive silver halide on a support, and containing an organic silver salt and a reducing agent for the organic silver salt,
A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible reducing agent-containing composite fine particles according to claim 6. 9. A heat-developable silver halide photographic material having a photosensitive layer containing a photosensitive silver halide on a support, and containing an organic silver salt and a reducing agent for the organic silver salt,
A silver halide photographic light-sensitive material for thermal development, comprising the water-dispersible organic silver salt-containing composite fine particles according to claim 7 and the water-dispersible reducing agent-containing composite fine particles according to claim 8. 10. The silver halide photographic light-sensitive material for thermal development according to claim 7, wherein the photosensitive layer has a water-soluble polymer and / or water-dispersible polymer particle as a binder. material. 11. The silver halide photographic light-sensitive material for thermal development according to claim 10, wherein 5% by weight or more of the binder is a water-soluble polymer. 12. The silver halide photographic light-sensitive material for thermal development according to claim 10, wherein the water-soluble polymer is gelatin.