JPS6275435A - Heat developable photosensitive material - Google Patents

Abstract

PURPOSE:To obtain a heat developable photosensitive material having high sensitivity and small thermal fogging by incorporating a core/shell type photosensitive silver halide particles in which the silver iodide content in the front layer of the photosensitive silver halide particles having 4-4mol% silver iodide content is loser than the silver iodide content in the inside layer into said material. CONSTITUTION:The silver iodide content of the photosensitive silver halide particles is 4-40mol%, more preferably 4-20mol%. The thermal fogging is little but the photographic sensitivity is low if the silver iodide content is <4mol%. The thermal fogging increases if the content exceeds 40mol%. The photosensitive silver halide particles are the core/shell type photosensitive silver halide particles in which the silver iodide content in the front layer of the particles is lower than the silver iodide content in the inside layer. The preferable silver halide component includes silver iodobromide and silver chlorobromide. The heat developable photosensitive material having the high sensitivity and small thermal fogging is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat-developable photosensitive material, and more particularly to a heat-developable photosensitive material with high sensitivity and low thermal fog.

BACKGROUND OF THE INVENTION A method in which the development step for obtaining an image is performed by dry heat treatment has many advantages over conventional wet methods in terms of processing time, cost, and concerns about pollution.

Regarding heat-developable photosensitive materials in which the above-mentioned development process can be carried out by dry heat treatment, for example, Japanese Patent Publication No. 43-4921 and No.
This is described in Japanese Patent No. 3-4924, which discloses a black and white type photothermographic material comprising an organic silver salt, silver halide and a reducing agent.

Attempts have also been made to improve such heat-developable photosensitive materials and obtain color images by various methods.

For example, JP-A-57-179840, JP-A No. 57-186
No. 744, No. 57-198458, No. 57-20
No. 7250, No. 58-40551, No. 58-5854
No. 3, No. 58-79247, No. 59-12431, No. 59-22049, No. 59-68730, No. 5
No. 9-124339, No. 59-1243.33, No. 5
No. 9-124331, No. 59-159159, No. 59
-181345, 59-159161, 58-
No. 116537, No. 58-123533, No. 58
-149046, 58-14947, etc.

The basic structure of a color type heat-developable photosensitive material for obtaining this color image consists of a photosensitive element and an image receiving element. It consists of a dye-donating substance, and a binder. In the present invention, only the photosensitive element is referred to as a heat-developable photosensitive material in a narrow sense.

In the former black and white type, optical information is given to the photosensitive silver halide by image exposure, and during thermal development, the exposed photosensitive silver halide and the reducing agent in the photosensitive layer are present in the vicinity. The catalytic action of silver halide causes an oxidation-reduction reaction to produce silver, and the exposed areas of the photosensitive layer turn black to form a silver image.

In addition, in the color type, optical information is given to the photosensitive silver halide by image exposure, and the developer that has or has not acted on the photosensitive silver halide during thermal development reacts with the dye-providing substance. The dye that forms the image is released or formed by the process. The image-forming dye obtained by thermal development is transferred to an image-receiving element to form an image.

In recent years, LEDs have been used as an exposure means for heat-developable photosensitive materials.
Attempts have been made to use light sources with low exposure illuminance such as SCRT, FOT, and semiconductor lasers.

On the other hand, the reduction of the time required to obtain an image is also being considered, and in particular for photosensitive materials suitable for rapid processing such as heat-developable photosensitive materials, studies are being carried out from various viewpoints. Studies are underway to improve the sensitivity of heat-developable photosensitive materials.

It is possible to increase the sensitivity of this heat-developable photosensitive material by increasing the content of silver iodide in the photosensitive silver halide, but on the other hand, increasing the color content of silver iodide causes an increase in thermal fog. The problem became clear.

On the other hand, it is possible to use a thermal fog preventive agent that reduces thermal fog, and examples of this thermal fog preventive agent include:
Water brocade compounds of U.S. Patent No. 3,589,903, N-halogen compounds of West German Patent No. 2,402,161, peroxides of West German Patent No. 2,500,508, and West German Patent No. 2,617.9.
No. 07 Sulfur Compound, U.S. Pat. No. 4,102,312
Palladium compounds of No. 53-28417, sulfinic acids of Japanese Patent Publication No. 53-28417, Research Disclosure No.

169077, mercaptotriazole of 169079, 1,2,4-triazole of US Pat. No. 4,137,079, and the like.

However, these thermal antifoggants are either extremely harmful to the human body or have little antifogging effect, and the reality is that no satisfactory thermal antifoggant has yet been found.

As a result of intensive studies, the present inventors found that silver halide grains containing core/shell type photosensitive silver halide grains containing silver iodide in a specific range and having a lower silver iodide content in the surface layer than in the inner layer. The inventors have discovered that by using an emulsion, a heat-developable photosensitive material with high sensitivity and low thermal fog can be obtained, leading to the present invention.

[Object of the Invention] Therefore, an object of the present invention is to provide a heat-developable photosensitive material having high sensitivity and low thermal fog.

[Structure of the Invention] The above-mentioned object of the present invention is to provide a photosensitive silver halide emulsion of a heat-developable photosensitive material containing photosensitive silver halide grains having a silver iodide content of 4 to 40 mol%; This is achieved by using a heat-developable photosensitive material containing core/shell type photosensitive silver halide grains in which the silver iodide content in the surface layer is lower than that in the inner layer.

[Specific Structure of the Invention] The photosensitive silver halide grains used in the present invention have a silver iodide content of 4 mol% to 40 mol%, more preferably a silver iodide content of 4 mol%. ~20 mol%.

When the silver iodide content exceeds the range of the present invention, that is, when the silver iodide content is less than 4 mol%, disadvantages such as low photographic sensitivity appear although there is little thermal fog. When the silver content exceeds 40 mol%, it becomes difficult to obtain uniform crystals of silver iodide-containing holes in the silver halide grains.
Furthermore, disadvantages such as large thermal fog appear.

Furthermore, the photosensitive silver halide grains used in the present invention are core/shell type photosensitive halogen grains in which the silver iodide content in the surface layer (synonymous with shell) is lower than that in the inner layer (synonymous with core). It is a silver oxide particle.

When the silver iodide content in the surface layer of the core/shell type photosensitive silver halide is higher than or equal to that in the inner layer, disadvantages such as large thermal fog appear.

Other silver halide components of the photosensitive silver halide containing silver iodide in the core of a core/shell type photosensitive silver halide grain in which the surface layer of the grain used in the present invention has a lower silver iodide content than the inner layer. Although there are no particular restrictions on the silver halide component, preferred silver halide components include silver iodobromide and silver chloroiodobromide.

The core of the photosensitive silver halide grains containing silver iodide used in the present invention is described by B. Gerafkides, Himy et al.
Physique Photographic (published by Ball Monte) (P, G 1afkides.

Chimie etPhysique photogr
aphique, paul montel)
(1967), Photographic Emulsion Chemistry by G. F. Tuffin (published by The Focal Press) (G, F.

[)uffin, photography E
Mulsion Chemistry.

The Focal Press) (1
966), V. L. Zelikman et al., Making and Coating Photographic Emulsions (The Focal Press) (V, L.

Zelikman etal, Making and
Coatingphotographic Emul
sion, The FocalPress)
(1964) and others.

That is, any of the acid method, neutral method, ammonia method, etc. may be used, but the ammonia method is particularly suitable. Further, as a method for reacting the soluble silver salt and the soluble halogen salt, any one of a one-sided mixing method, a simultaneous mixing method, a combination thereof, etc. may be used. It is also possible to use the reverse north method in which silver halide grains are formed in an excess of silver ions. As one of the simultaneous mixing methods, it is also possible to use the Chondrald double jet method, in which the pAg of the solution in the reaction vessel in which silver halide is produced is arbitrarily controlled, and the addition rate of the silver and halogen solutions is controlled. According to this method, a so-called monodisperse silver halide emulsion in which the crystal shape and grain size of each side of the silver halide grains are nearly uniform can be obtained.

In the present invention, the above-mentioned monodisperse silver halide emulsion is defined as one having a particle size distribution in which the variation in the size of silver halide grains contained in the emulsion is less than a certain percentage of the average grain size as shown below. means. The grain size distribution of a photosensitive silver halide emulsion (hereinafter referred to as a monodisperse emulsion) consisting of a group of photosensitive silver halide grains with uniform grain morphology and small variation in grain size exhibits an almost normal distribution;
When the standard deviation is easily determined and the width of the distribution is defined by the relational expression, the preferred width of the distribution of the photosensitive silver halide grains used in the present invention is 15%.
or less, and more preferably monodispersity with a distribution width of 10% or less.

The core/shell type photosensitive silver halide grain emulsion used in the present invention can be produced by using monodisperse photosensitive silver halide grains as a core and coating the core with a shell.

In order to form the core into monodisperse silver halide grains, grains of a desired size can be obtained by the double jet method while keeping the pAQ constant. Furthermore, the method described in JP-A-54-48521 can be applied to silver halide emulsions containing highly monodisperse photosensitive silver halide. In a preferred embodiment of the method, an aqueous potassium gelatin solution and an ammoniacal silver nitrate aqueous solution are added to an aqueous gelatin solution containing silver halide seed particles.
It is produced by an addition method in which the addition rate is varied as a function of time. At this time, by appropriately selecting the time function of addition rate, pH, l)Ag, temperature, etc., it is possible to obtain 1 q of silver halide emulsion containing highly monodisperse core silver halide grains.

Monodisperse core/shell type photosensitive silver halide grains used in the present invention can be produced by sequentially growing shells using monodisperse core grains as described above according to the Kurahiki emulsion manufacturing method. A silver halide emulsion containing silver halide can be obtained.

In the core/shell type photosensitive silver halide grains used in the present invention, the thickness of the shell covering the core is preferably 0.05% to 90% of the silver halide grain size, more preferably 1% to 80% of the silver halide grain size. % range.

The core/shell type photosensitive silver halide grains used in the present invention have a silver iodide content of 4 to 40 mol% as a whole grain.
However, in the silver halide composition of the core,
The silver iodide content is preferably 4 mol% to 20 mol%, and in the silver halide composition of the shell, the silver iodide content is 0.
Preferably it is from mol% to 6 mol%.

Furthermore, the core/shell type photosensitive silver halide grains used in the present invention are the surface of the grains! It is sufficient that the silver iodide content in J (shell) is lower than inner m<core, but preferably the silver iodide content in the surface layer is 2 mol % or more lower than the silver iodide content in the inner layer.

There is no particular restriction on the average grain size of the photosensitive silver halide grains used in the present invention, but it is preferably 0.01
μm to 5.0 μm, more preferably 0.05 μm
~2.0 μm.

In the present invention, the average particle size of photosensitive silver halide grains refers to the diameter in the case of spherical silver halide grains, and the projected image of the same area in the case of cubic or non-spherical grains. The average value of the diameter when converted into a circular image, where the individual particle size is ri and the number is ni, is defined by the following formula.

Note that the particle size can be measured by various methods commonly used in the technical field for the above purpose. A typical method is Loveround's "Particle Size Analysis Method JA."

S, T, M, Symposium on Light Microscopy, 1955, pp. 94-122 or Chapter 2 of ``The Theory of the Photographic Process'' by Mies and James, 3rd edition, Macmillan Publishing Co., Ltd. (1966). Are listed. The particle size can be measured using the projected area or approximate diameter of the particle.

If the particles are of substantially uniform shape, the particle size distribution can be described fairly accurately as diameter or projected area.

The photosensitive silver halide emulsion containing photosensitive silver halide grains used in the present invention may be chemically sensitized by any method in the field of photographic technology.

Such sensitization methods include various methods such as gold sensitization, sulfur sensitization, gold-sulfur sensitization, and reduction sensitization.

In the present invention, as another method for preparing photosensitive silver halide, a photosensitive silver salt-forming component may be allowed to coexist with a valent silver salt described below to form photosensitive silver halide in a part of the organic silver salt. can. The photosensitive silver salt forming component used in this preparation method is an inorganic halide, for example, a halide represented by MXn (here, M 1.t H atom, N
represents H41 or a metal atom; As a metal atom,
Lithium, sodium, potassium, rubidium, cesium, copper, gold, beryllium, magnesium, calcium,
Strontium, barium, zinc, cadmium, mercury,
Aluminum, indium, lanthanum, luteum, thallium, germanium, tin, lead, antimony, bismuth, chromium, molybdenum, tungsten, manganese, rhenium, iron, cobalt, nickel, Odium, palladium, osmium, iridium, platinum, Examples include cerium. ), halogen-containing gold hole complexes (e.g., K2 Pt
Cff1s, K2Pt13rs, HAu
CQq.

(NH4)2 Ir C/! e, (NH4>3 Ir
CF! s.

(NH4)2 RLI C1s, (NH4)a RU
Cu6゜(NH4)2 Rh C16(NH4)3 R
h Brs, etc.), onium halides (e.g., quaternary ammonium halides such as tetramethylammonium bromide, trimethylphenylammonium bromide, cetylethyldimethylammonium bromide, 3-methylthiazolium bromide, trimethylbenzylammonium bromide, tetraethylph A) quaternary phosphine halides such as sulfonium bromide, tertiary sulfonium halides such as benzylethylmethylsulfonium bromide, 1-ethylthiazolium bromide, etc.), halogenated hydrocarbons (e.g. iodoform, bromoform, carbon bromide, 2-bromo-2-methylpropane, etc.), N-halogen compounds (N-chlorosuccinimide, N-bromosuccinimide, N-bromophthalimide, N-bromoacetamide, N-iodosuccinimide, -Bromophthalazinone, N-chlorophthalazinone, N-bromoacetanilide, N,N-dibromobenzenesulfonamide, N-bromo-N-methylbenzenesulfonamide, 1,3-dibromo-4,4-
dimethylhydantoin, etc.), and other halogen-containing compounds (for example, triphenylmethyl chloride, triphenylmethyl bromide, 2-bromobutyric acid, 2-bromoethanol, etc.).

These photosensitive silver salt-forming components and the photosensitive silver halide grains can be used in combination in various methods.
g, more preferably 0.1 g to
It is 10g.

The photosensitive silver halide used in the present invention can be optically spectral sensitized to a desired wavelength range using a dye known as a sensitizing dye.

Typical spectral sensitizing dyes used in the present invention include, for example, cyanine, merocyanine, complex (trinuclear or tetranuclear) cyanine, holopolar cyanine, styryl, hemicyanine, oxonol, and the like. Among the cyanine dyes, those having a basic nucleus such as thiazoline, oxazoline, viroline, pyridine, oxazole, deazole, selenazole, and imidazole are more preferred. Such nuclei include alkyl groups, alkylene groups,
It may have an enamine group capable of forming a hydroxyalkyl group, a sulfoalkyl group, or a carboxyalkyl fused carbocyclic or heterocyclic ring. Further, it may be symmetrical or asymmetrical, and the methine chain or polymethine chain may have an alkyl group, a phenyl group, an enamine group, or a heterocyclic substituent.

In addition to the above-mentioned basic nucleus, merocyanine dyes have acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidione nucleus, thiazolidinedione nucleus, barbylic acid nucleus, thiazolinthione nucleus, malonitrile nucleus, and pyrazolone nucleus. Good too.

These acidic nuclei may be further substituted with an alkyl group, an alkylene group, a phenyl group, a carboxyalkyl group, a sulfoalkyl group, a hydroxyalkyl group, an alkoxyalkyl group, an alkylamine group or a heterocyclic nucleus. If necessary, these dyes may be used in combination.

Furthermore, ascorbic acid derivatives, azaindene cadmium salts, d-sulfonic acids, etc., such as U.S. Pat. No. 2,933,3
A supersensitizing additive that does not absorb visible light, such as those described in the specifications of No. 90, No. 2, No. 937,089, can be used in combination.

The amount of these sensitizing dyes added is 1.times.10@-4 mol to 1 mol per mol of photosensitive silver halide. More preferably,
1×10 −mol to 1×10 −′ mole.

The heat-developable photosensitive material of the present invention can be applied to any photosensitive material that forms an image by heat development.

Examples include black-and-white types that form a silver image by heat development, and color types that include a dye-providing substance. In this latter color type, there are further monochromatic materials having a single color, for example, a black dye-providing substance or any other monochrome dye-providing substance, and multicolor, for example, heat-developable color photosensitive materials with yellow, cyan, and magenta color development. can be mentioned. In the color type, a method is usually used in which only the developed dye is transferred to the image receiving member.

The present invention exhibits particularly favorable effects when applied to the latter color type.

In the black-and-white type in which the heat-developable photosensitive material of the present invention forms a silver image, the photosensitive layer on the support basically contains (1) photosensitive silver halide, (2) a reducing agent, and (3) a binder. Furthermore, (4) an organic silver salt is contained as necessary.

In addition, in the color type that forms a dye image, basically one photosensitive layer on the support contains (1) photosensitive silver halide, (2) reducing agent, (3) binder, and (5)
A dye-providing substance and, if necessary, (4) a silver salt are contained. However, these do not necessarily need to be contained in a single photosensitive layer; for example, the photosensitive layer may be divided into two layers, and the components (1), (2), (3), and (4) may be added to one side of the photosensitive layer. layer and the other layer adjacent to this photosensitive layer.
, a dye-providing substance (5), etc. may be contained separately in two or more photosensitive layers as long as they are in a state where they can react with each other.

Further, the photosensitive layer may be divided into two or more layers, such as a high-sensitivity layer and a low-sensitivity layer, and furthermore, other layers having different color sensitivities may have two or more photosensitive layers. Alternatively, it may have various photographic constituent layers such as an overcoat layer, an undercoat layer, a bagging layer, and an intermediate layer.

Similar to the thermal image-sensing layer of the present invention, coating solutions for the protective layer, intermediate layer, undercoat layer, back layer, and other photographic constituent layers are prepared using the dipping method, air knife method, and curtain coating method. Alternatively, a photothermographic material can be prepared by various coating methods such as the popper coating method described in US Pat. No. 3,681.294.

Furthermore, if desired, two or more layers can be applied simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095.

The components used in the photosensitive layer and other photographic constituent layers of the heat-developable photosensitive material of the present invention are coated on a support, and the coating thickness after drying is preferably 1 to 1,000 μm, more preferably 30 μm. ~20 μm.

Margins Below In the heat-developable photosensitive material of the present invention, various organic silver salts can be used, if necessary, for the purpose of increasing sensitivity and improving developability.

Examples of organic silver salts used in the heat-developable photosensitive material of the present invention include Japanese Patent Publications No. 43-4921, No. 44-28582, No. 45-18416, No. 45-12700, No. 45-
No. 22185, JP-A-49-52626, JP-A No. 52-3
No. 1728, No. 52-137321, No. 52-14
No. 1222, No. 53-36224 and No. 53-37
Publications such as No. 610 and U.S. Patent No. 3,330,6
No. 33, No. 3,794,496, No. 4,105,
No. 451, No. 4,123.274, No. 4,168
Silver salts of aliphatic carboxylic acids such as silver laurate, silver myristate, silver valmitate, silver stearate, silver arachidonate, silver behenate, Silver aromatic carboxylates such as α-(1-phenyltetrazolethio)silver acetate, such as silver benzoate, silver phthalate, etc., Japanese Patent Publication No. 44-26582, No. 45
-12700, 45i8416, 45-221
No. 85, JP-A-52-31728, JP-A No. 52-1373
No. 21, JP-A-58-118638, JP-A No. 58-118
Silver salts of imino groups such as those described in publications such as No. 639, such as silver benzotriazole, silver 5-nitrobenzotriazole, silver 5-chlorobenzotriazole, silver 5-chlorobenzotriazole, etc.
-methoxybenzotriazole silver, 4-sulfobenzotriazole silver, 4-hydroxybenzotriazole silver,
5-aminobenzotriazole silver, 5-carboxybenzotriazole silver, imidazole silver, benzimidazole silver, 6-nidropenzimidazole silver, pyrazole silver, urazole silver, 1.2.4-triazole silver, 1 day -
Tetrazole silver, 3-amino-5-benzylthio-1,
2,4-t-lyazole silver, saccharin silver, phthalazinone silver, phthalimide silver, etc., 2-mercaptobenzoxazo-/silver, mercaptooxadiazole brocade,
2-mercaptobenzib azole silver, 2-mercaptobenzimidazole silver, 3-mercapto-4-phenyl-1,2,4-triazole silver, 4-hydroxy-6-
Examples include methyl-1,3,38,7-titrazaindene silver and 5-methyl-7-hydroxy-1,2,3,4,6-pentazaindene silver. Among the above organic silver salts, imino group silver salts are preferred, and silver salts of benzotriazole derivatives are particularly preferred, and silver salts of sulfobenzotriazole derivatives are particularly preferred.

The organic silver salts used in the present invention may be used alone or in combination of two or more, and isolated ones may be used by dispersing them in a binder by appropriate means, or they may be used in a suitable form. The silver salt may be prepared in a binder and used as is without isolation.

The amount of the organic silver salt used is preferably 0.01 to 500 mol, more preferably 0.1 to 100 mol, per 1 mol of photosensitive silver halide.

As the reducing agent used in the photothermographic material of the present invention, those commonly used in the field of photothermographic materials can be used, such as those disclosed in U.S. Pat. No. 3,531,286 and U.S. Pat.
．． Nos. 761,270 and 3,764,328, as well as R D No. 12146 and No. 3,764,328.
, 15108, same No.

15127 and JP-A-56-27132, p-phenylenediamine type and p-aminophenol type developing agents, phosphyroamide phenol type and sulfonamide phenol type developing agents, and Dracin type color developing agent Mulberry. Can be mentioned. Also, U.S. Patent No. 3,
342,599, 3,719,492, JP-A-53-135628, JP-A-54-79035, etc., color developing agent precursors and the like can also be used.

As a particularly preferable reducing agent, JP-A-56-146133
Examples include reducing agents represented by the following general formula (1) described in No.

General formula (1) In the formula, R and R represent a hydrogen atom or an alkyl group having 1 to 30 carbon atoms (preferably 1 to 4) which may have an n substituent, and R and R represent a closed ring. may be used to form a heterocycle. R, R"da R and R are hydrogen atoms, halogen atoms, hydroxy groups,
represents an amide group, an alkoxy group, an acylamido group, a sulfonamide group, an alkylsulfonamide group, or an alkyl group having 1 to 30 carbon atoms (preferably 1 to 4) that may have a substituent, and R and R and R and R may each be ring-closed to form a heterocycle. M is an alkali metal atom,
Represents a compound containing an ammonium group, a nitrogen-containing organic base, or a quaternary nitrogen atom.

The nitrogen-containing organic base in the above general formula (1) is a compound containing a basic nitrogen atom capable of forming a salt with an inorganic acid, and particularly important organic bases include amine compounds. Examples of chain amine compounds include primary amines, secondary amines, and tertiary amines, and examples of cyclic amine compounds include pyridine, quinoline, and piperidine, which are well-known examples of typical heterocyclic organic bases. , imidazole and the like. In addition, compounds such as hydroxylamine, hydrazine, and amidine are also useful as chain amines. Examples of nitrogen-containing organic bases include inorganic acid salts of nitrogen-containing bases (e.g. salt M salt, lii!I
N salts, nitrates, etc.) are preferably used.

On the other hand, examples of the compound containing quaternary nitrogen in the above general formula include salts or hydroxides of nitrogen compounds having a tetravalent covalent bond.

Below is a margin.Next, preferred specific examples of the reducing agent represented by the general formula (]) are shown below.

(R-1) (R-2) (R-3) (R-4) F3 (Nu5) (R-6) (R-7) ('R-8) (R-9) Hs (R= 10 ) (R-11) (R-12) (R-45) (R-16) (R-17) (1,18) (R-19) Fs (R-20) (R-21) (R -22) (R-23) The reducing agent represented by the above general formula (1) can be prepared by a known method,
For example, Houben Peil, Mesosden der Organitsien Hemi, Band XI/2 (Houben
-Weyl, Methoden der Oraan
ischen Chemie, Band X I
/2) It can be synthesized according to the method described on pages 645-703.

On the other hand, the dye-donating substance is disclosed in JP-A No. 57-179840,
In the case of a compound that releases a dye upon oxidation, a compound that loses the ability to release a dye upon oxidation, a compound that releases a dye upon reduction, as shown in No. 58-58543, No. 59-152440, and No. 59-154445, Alternatively, when obtaining only a silver image without containing a dye-providing substance, a reducing agent as described below can also be used.

For example, phenols (e.g. p-phenylphenol, p-methoxyphenol, 2,6-tert-
Butyl-p-cresol, N-methyl-p-aminephenol, etc.>, sulfonamide phenols [e.g. 4-
Benzenesulfonamidophenol, 2-benzenesulfonamidophenol, 2,6-dichloro-4-benzenesulfonamidophenol, 2,6-dipromo-4-
(p-toluenesulfonamide)phenol, etc.], or polyhydroxybenzenes (e.g., hydroquinone,
tert-butylhydroquinone, 2,6-dimethylhydroquinone, chlorohydroquinone, carboxyhydroquinone, catechol, 3-carboxylic acidol, etc.), naphthols (e.g. α-naphthol, β-naphthol, 4-aminonaphthol, 4-methoxy naphthol, etc.), hydroxybinaphthyls and methylenebisnanano-1-ols [e.g. 1,1'-dihydroxy-2,2'
-binaphthyl, 6.6'-dibromo-2,2'-dihydroxy-1,11-binaphthyl, 6.6-sinitro2.2'-dihydroxy-1,1'-binaphthyl, 4.
4'-dimethoxy-1,1'-dihydroxy-2,2'
-binaphthyl, bis(2-hydroxy-1-naphthyl)
Methane, etc., methylene bisphenols [e.g. 1.1
-bis(2-hydroxy-3,5-dimethylphenyl)
-3゜5.5-trimethylhexane, 1,1-bis(2
-hydroxy-3-tert-butyl-5-methylphenyl)methane, 1,1-bis(2-hydroxy-3,5
-di-tert-butylphenyl)methane, 2,6-methylenebis(2-hydroxy-3-tert-butyl-
5-methylphenyl)-4-methylphenol, α-phenyl-α, α-bis(2-hydroxy-3,5-di-tert-butylphenyl)methane, α-phenyl-α
, α-bis(2-hydroxy-3-tert-butyl-
5-methylphenyl)methane, 1,1-bis(2-hydroxy-3,5-dimethylphenyl)-2-methylbroban, 1.1.5.5-tetrakis(2-hydroxy-
3,5-dimethylphenyl)-2,4-ethylpentane, 2,2-bis(4-hydroxy-3゜5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3
-medyru-5-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3,5-di-tert)
t-butylphenyl)bropane, etc.], ascorbic acids, 3-pyrazolidones, pyrazolones, dracines, and paraphenylenediamines.

These reducing agents can be used alone or in combination of two or more. The amount of reducing agent used depends on the type of photosensitive silver halide used, the type of acid silver salt, and the type of other additives, but it is usually used per mol of photosensitive silver halide. in the range of 0.01 to 1500 mol,
Preferably it is 0.1 to 200 mol.

Examples of the binder used in the heat-developable photosensitive material of the present invention include synthetic or natural polymers such as polyvinyl butyral, polyvinyl acetate, ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinylpyrrolidone, gelatin, and phthalated gelatin. One or more molecular substances can be used in combination. In particular, it is preferable to use gelatin or its M1 form together with a hydrophilic polymer such as polyvinylpyrrolidone or polyvinyl alcohol, and more preferably the following binder described in Japanese Patent Application No. 1042.19/1982.

This binder includes gelatin and vinylpyrrolidone polymer. The vinylpyrrolitonopolymer may be polyvinylpyrrolidone, which is a homopolymer of vinylpyrrolidone, or a copolymer of vinylpyrrolidone with one or more other monomers copolymerizable (including graft copolymers). ). These polymers can be used regardless of their degree of polymerization. Polyvinylpyrrolidone may be substituted polyvinylpyrrolidone, and preferred polyvinylpyrrolidone has a molecular weight of 1.000 to 40
0,000. Other monomers copolymerizable with vinylpyrrolidone include (meth)acrylic acid esters such as acrylic acid, methacrylic acid and its alkyl esters, vinyl alcohols, vinyl imidazoles, (meth)acrylamides, and vinyl carbinol. kind,
Examples include vinyl monomers such as vinyl alkyl ethers, but it is preferable that polyvinylpyrrolidone accounts for at least 20% (weight %, same hereinafter) of the composition ratio.

A preferable example of such a copolymer has a molecule whose molecular weight is s, ooo
~400,000.

The gelatin may be lime-treated or acid-treated, and may be ossein gelatin, big skin gelatin, hydrogelatin, or modified gelatin obtained by esterifying or phenylcarbamoylating these gelatins.

In the above binder, gelatin preferably accounts for 10 to 90% of the total binder matrix, more preferably 20 to 60%, and vinylpyrrolidone accounts for 5 to 90%.
It is preferably 10 to 80%, more preferably 10 to 80%.

The binder may contain other polymeric substances,
Gelatin and molecules fM 5,000 to 400. A mixture of polyvinylpyrrolidone and one or more polymeric substances of 5,000 to 400.
000 vinylpyrrolidone copolymer and one or more other polymeric substances is preferred. Examples of the relaxing polymer substances used include polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyvinyl butyral, polyethylene glycol, polyethylene glycol ester, proteins such as cellulose derivatives, and polysaccharides such as starch and gum arabic. Examples include natural substances. These range from 0 to 85%, preferably from 0 to 7
It may be contained in an amount of 0%.

Note that the vinyl pyrrolidone polymer may be a crosslinked polymer, but in this case, it is preferable to crosslink it after coating it on the support (including the case where the crosslinking reaction progresses by leaving it to stand).

The Ω of the binder used is usually 0.05 (1 to 50 (l), preferably 0.1 g to 50 (l) per 1 x' per layer.
10(].

Supporting phrases used in the heat-developable photosensitive material of the present invention include:
For example, synthetic plastic films such as polyethylene film, cellulose acetate film and polyethylene terephthalate film, polyvinyl chloride, paper supports such as photographic base paper, printing paper, baryta paper, and resin coated sheets, and the above synthetic plastic films. Examples include a support provided with a reflective layer.

In addition to the above-mentioned components, various additives may be added to the heat-developable photosensitive material of the present invention, if necessary.

For example, as a development accelerator, U.S. Patent M3,220,8
No. 40, No. 3,531,285, No. 4,012,
No. 260, No. 4,060,420, No. 4,088
, No. 496, No. 4,207, 392 @ each specification, RD
No. 15733, No. 15734, N.
O, 15776, JP-A No. 56-130745, 5
Alkali release agents such as urea and guanidium trichloroacetate described in No. 6-132332, etc., Japanese Patent Publication No. 1973
-12700, organic acids described in US Pat. No. 3,667.
Non-aqueous polar solvent compound having 100-, -302-, -80- groups described in No. 959, U.S. Patent No. 3,438.7
Meltformer-1 described in '76 U.S. Pat. No. 3,666
．． 477, and polyalkylene glycols described in JP-A-51-19525. Also, as a coloring agent,
For example, JP-A-46-4928, JP-A-46-6077,
49-5019@, 49-5020, 49-
No. 91215, No. 49-107727, No. 50-
No. 2524, No. 50-67132, No. 50-6764
No. 1, No. 50-114217, No. 52-33722 @
, No. 52-99813, No. 53-1020, No. 53
-55115, 53-76020, 53-12
No. 5014, No. 54-156523, No. 54-1
No. 56524, No. 54-156525, No. 54-
No. 156526, No. 55-4060, No. 55-40
61, West German Patent No. 55-32015, West German Patent No. 2,140,40 et al., West German Patent No. 2,147,063, West German Patent No. 2.220,618, and US Patent No. 3.08 (1).
, No. 254, No. 3,847,612, No. 3,7.
No. 82,941, No. 3,994,732, No. 4
, phthalazinone, phthalimide, pyrazolone, quinazolinone, N-hydroxynaphthalimide, benzoxazine, naphthoxazinedione, which is a compound described in each specification such as No. 123,282 and No. 4,201,582; 3-dihydro-phthalazinedione, 2.
3-dihydro-1,3-oxazine-2,4-dione,
Oxypyridine, aminopyridine, hydroxyquinoline, aminoquinoline, isocarbostyryl, sulfonamide, 2H-1,3-benzothiazine-2,4-(3H)
dione, benzotriazine, mercaptotriazole,
Dimercabutotetrazabentalene, phthalic acid, naphthalic acid, phthalamic acid, etc., mixtures of one or more of these with imidazole compounds, and at least acids or acid anhydrides such as phthalic acid, naphthalic acid, etc. Combinations of phthalazine and maleic acid, itaconic acid, quinolinic acid, gentisic acid, etc. can be mentioned. Also, JP-A-58
3-amino-5-mercapto-1,2,4-triazoles, 3-acylamino-5-mercapto-1 described in No. -189628 and No. 58-193460.
, 2,4-1-riazoles are also effective.

Furthermore, as an antifoggant, for example,
No. 7-11113, JP-A-49-90118, JP-A No. 49
-10724, 49-97613, 50-1
No. 01019, No. 49-130720, No. 50-
No. 123331, No. 51-47419, No. 51-57
435@, No. 51-78227, No. 51-10433
No. 8, No. 53-19825M, No. 53-20923,
No. 51-50725, No. 51-3223, No. 51-
No. 42529, No. 51-41124, No. 54-518
No. 21, No. 55-93149@, etc., as well as British Patent No. 1.455,271, U.S. Patent No. 3,885,
No. 968, No. 3,700,457, No. 4,137
, No. 079, No. 4,138,265, West German Patent No. 2
, No. 617,907, or oxidizing agents (for example, N-halogenoacetamide, N-halogenosuccinimide, perchloric acid and its salts, oxides, persulfates, etc.), or acids and their salts (e.g., sulfinic acid, lithium laurate, rosin, diterpene acid, thiosulfonic acid, etc.), or sulfur-containing compounds (e.g., mercapto compound-releasing compounds, diouracil, Disulfide, simple sulfur, mercapto-L 2,4-triazole, thiazolinthione, polysulfide compounds, etc.), and other compounds such as ogisazoline, 1.2°4-triazole, phthalimide, etc. Further, other antifoggants include Thiol (preferably a thiophenol compound) compound described in Japanese Patent Publication No. 9359-111636 is also effective.

In addition, as other antifoggants, Japanese Patent Application No. 59-565
Hydroquinone described in No. 06; hexaconductor (e.g. di-
t-octylhydroquinone, dodecanylhydroquinone, etc.) and hydroquinone derivatives and benzotriazole derivatives (e.g., 4-
Sulfobenzotriazole, 5-carboxybenzotriazole, etc.) can be preferably used in combination.

In addition, as a stabilizer, a print-out preventive agent may be used at the same time, especially after processing, for example, as disclosed in JP-A No. 48-45228, JP-A No. 50-119624, and JP-A No. 50-120328.
Halogenated hydrocarbons described in No. 53-46020, specifically tetrabromobutane, tribromoethanol, 2-bromo-2-tolylacetamide, 2
-Bromo-2-tolylsulfonylacetamide, 2-tribromomethylsulfonylbenzothiazole, 2,4-
Examples include bis(tribromomethyl)-6-methyltriazine.

Also, Japanese Patent Publication No. 46-5393, Japanese Patent Publication No. 50-54329
A post-treatment may be carried out using a sulfur-containing compound as described in No. 50-77034.

Furthermore, U.S. Patent No. 3,301,678;
No. 506.444, No. 3,824,103, No. 3
, 844,788, as well as the isothiuronium-based stabilizer precursor described in U.S. Patent No. 3,6
No. 69,670, No. 4,012,260, No. 4,
It may contain activator stabilizer precursor etc. described in No. 060,420 Mei 1@.

Also, sucrose, NH4Fe (S04)2 ・1282
A water release agent such as No. 0 may also be used;
6-132332@, water may be supplied and thermal imaging may be performed.

In addition to the above-mentioned components, the heat-developable photosensitive material of the present invention further contains antihalation dyes, optical brighteners, g!
Film-forming agent Various additives such as antistatic agents, plasticizers, and spreading agents, coating aids, etc. can be added.

When the heat-developable photosensitive material of the present invention is a color type, a dye-providing substance is used.

Dye-providing substances that can be used in the present invention will be explained below. As the dye-providing substance, photosensitive silver halide and/or acetic acid used as necessary are used. ! ! ! Any substance that participates in the 37-element reaction of salts and can form or release a diffusible dye as a function of the reaction may be used. , which forms a negative dye image when negative-working silver halide is used) and a positive-working dye-donor that acts negatively (i.e., forms a positive dye image when negative-working silver halide is used). can be classified as (forming an image).

Negative dye-donating substances are further classified as follows.

Margin below Releases a diffusible dye when oxidized Release type compound　　Formation type compound Each dye-providing substance will be further explained.

Examples of the reducible dye-releasing compound include compounds represented by general formula (2).

General formula (2) % formula % In the formula, Car is a reducing substrate (so-called carrier) that is oxidized and releases a dye upon reduction of the photosensitive silver halide and/or the organic silver salt used as necessary. , Dy
e is a diffusible dye residue.

Specific examples of the above-mentioned reducible dye-releasing compounds include JP-A-57-179840, JP-A-58-116537@, JP-A-5
No. 9-60434, No. 59-65839, No. 59-7
No. 1046, No. 59-87450, No. 59-8873
No. 0, No. 59-123837, No. 59-165054
No. 59-165055, for example, the following compounds are listed.

Below is a blank space illustrating a dye-donor substance OC 9ω OC+6. Hi3(a) is another reducing dye-releasing compound, and C is, for example, represented by the general formula (3).
Examples include compounds represented by:

General formula (3) In the formula, A+ and A2 each represent a hydrogen atom, a human Ooxy group, or an amino group, and Dye is Dy represented by the general formula (2).
It is synonymous with e. Specific examples of the above compounds are given in JP-A-59-1
No. 24329.

As a coupled dye-releasing compound, general formula (4) is used.
Examples include compounds represented by:

General formula (4) % formula % In the formula, CD+ is a carrier group (so-called coupler residue) that can react with the infused form of a reducing agent to release a diffusible dye, and J is a divalent bond. group, the bond between CI)+ and J is cleaved by reaction with the oxidized form of the reducing agent. n
l represents ◯ or 1, and Dye has the same meaning as defined in general formula (2). In addition, CD+ is preferably substituted with various ballast groups in order to make the coupled dye-releasing compound non-diffusible, and the ballast group has 8 or more carbon atoms ( (more preferably 12 or more) ta groups, or hydrophilic groups such as sulfo groups and carboxy groups, or 8 or more (more preferably 12 or more) carbon atoms and hydrophilic groups such as sulfo groups and carboxy groups. It is a group having both. Another particularly preferred ballast group can include polymer chains.

Specific examples of the compound represented by the above general formula (4) include JP-A-57-186744 and JP-A-57-122596.
No. 57-160698, No. 59-174834, No. 57-224883, No. 59-159159,
They are described in each specification of Japanese Patent Application No. 59-104901, and include, for example, the following compounds.

CH3 of the exemplary dye-providing substance ■ As a coupled dye-forming compound, general formula (5) is used.
Examples include compounds represented by:

General formula (5) % formula %) In the formula, CI)2 is an organic group (so-called coupler residue) that can react with the oxidized form of the reducing agent (coupling reaction) to form a diffusive dye. , F represents a divalent bonding group, and B represents a ballast group.

The coupler residue represented by C1)2 preferably has a molecular size of 100 or less, more preferably 500 or less, in view of the diffusibility of the dye formed.

Further, the ballast group is preferably the same as the ballast group defined in general formula (4), and particularly has 8 or more (more preferably 12 or more) carbon atoms and a hydrophilic group such as a sulfo group or a carboxy group. Groups having both are preferred, and polymer chains are more preferred.

The coupled dye-forming compound having a polymer chain is preferably a polymer having a repeating unit derived from a single m compound represented by the general formula (6).

General formula (6) % formula %) In the formula, CI)2 and F have the same meanings as defined in general formula (5), Y represents an alkylene group, arylene group or aralkylene group, and f is 0 or 1 and Z is 2
L represents an ethylenically unsaturated group or a group having an ethylenically unsaturated group.

Specific examples of the coupled dye-forming compounds represented by general formulas (5) and (6) include JP-A-5912433;
No. 9, No. 59-1.91345, patent application No. 58-109
No. 293, No. 59-179657, No. 59-18
No. 1604, No. 59-182506, No. 59-18
No. 2507, specification 8, etc., and include, for example, the following compounds.

The following margins are exemplified dye-donor substances C0OH [Phase] Polymer OH x: 60% by weight y: 40% by weight cH3 O″Itf% N: Needle O only!-λ Below margin In the above general formula (4, (5) and (6), C
More specifically, the coupler residue defined by D+ or CI2 is preferably a group represented by the following general formula.

General formula (7) General formula (8) General formula (?) General formula (to) General formula (11) General formula (1z) General formula (13) General formula (/4-
) General formula (I5) General formula ()6
)#9 In the formula, R, R, R and R are each a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an acyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group. group, carbamoyl group, sulfamoyl group, acyloxy group, amim L alkoxy group, aryloxy group, siam L ureido group, alkylthio group,
It represents an arylthio group, a carboxy group, a sulfo group, or a heterocyclic residue, which can further include a hydroxyl group, a carboxy group, a sulfo group, an alkoxy group, a cyano group, a nitro group, an alkyl group, an aryl group, an aryloxy group, an acyloxy group,
It may be substituted with an acyl group, sulfamoyl group, carbamoyl group, imide group, halogen atom, or the like.

These substituents are selected depending on the purpose of Cp+ and CI)2, and as mentioned above, in Cpl, one of the substituents is preferably a ballast, and in C112, it is preferable to improve the diffusivity of the dye formed. In order to increase the molecular weight, the substituents are preferably selected to have a molecular weight of 700 or less, more preferably 500 or less.

As a positive dye-donating substance, for example, the following general formula (1
There is an oxidizable dye-releasing compound represented by 7>.

In the formula, Wl represents a collection of atoms necessary to form a quinone ring (which may have a substituent on this ring),
R represents an alkyl group or a hydrogen atom, R represents an oxygen atom, or R+7- represents -N-. ) or -8O2-, r is O
or 1, and Dye has the same meaning as defined in general formula (2). A specific example of this compound is JP-A-59-1
66954, No. 59-154445, etc., and there are, for example, compounds below 1 s.

The following general formula (18) is used as a positive dye-donor substance for each column.
There are compounds that lose their dye-releasing ability when oxidized, such as the compound represented by:

General formula (18) In the formula, W2 represents a collection of atoms necessary to form a benzene ring (which may have a substituent on the ring), R,
r, E, and Dye have the same meanings as defined in general formula (17). A specific example of this compound is JP-A-59-1243.
No. 29, No. 59-154445, etc., and include, for example, the following compounds.

O Hereinafter, all white Still another positive dye-providing substance is expressed by the following general formula (
Examples include compounds represented by 19).

General formula (19) In the above formula, W2, R'', and Dye are represented by general formula (1
It has the same meaning as defined in 8).

Specific examples of this compound are described in JP-A-59-154445, etc., and include the following compounds.

10□ The following are all white general formulas (2), (3), (4), (17), (1
The residue of the diffusible dye represented by Dye in 8) and (19) will be explained in further detail. The residue of the diffusible dye preferably has a molecular size of 800 or less, more preferably 600 or less for the sake of dye diffusivity, and includes azo dyes, azomethine dyes, anthraquinone dyes, naphthoquinone dyes, styryl dyes, and nitro dyes. , quinoline dyes, carbonyl dyes, phthalocyanine dyes, and the like.

These dye residues may be in a temporary short-waveform form that allows multiple colors during thermal development or transfer. In addition, these dye residues are used for the purpose of increasing the light resistance of images, for example, in
Chelatable dye residues described in No. 48765 and No. 59-124337 are also preferred.

These dye-providing substances may be used alone or in combination of two or more. The use thereof is not limited, and depends on the type of dye-providing substance, whether it is used alone or in combination of two or more, and whether the photographic constituent layer of the light-sensitive material of the present invention is a single layer or a multilayer of two or more layers. It may be determined accordingly, but for example, the usage 1 can be from 112 o, oosg to 50g, preferably from 0.1Q to 10g.

The dye-providing substance used in the present invention can be incorporated into the photographic constituent layer of the heat-developable light-sensitive material using any method. Cresyl phosphate, etc.) and then subjected to ultrasonic dispersion, or dissolved in an alkaline aqueous solution (e.g., 10% sodium hydroxide aqueous solution, etc.) and then neutralized with Mineral M (e.g., hydrochloric acid or nitric acid, etc.). Alternatively, it can be used after being dispersed in a ball mill with an aqueous solution of an appropriate polymer (eg, gelatin, polyvinyl butyral, polyvinylpyrrolidone, etc.).

Various exposure means can be used for the heat-developable photosensitive material of the present invention. The latent image is created 19 by imagewise exposure to radiation, including visible light. Light sources commonly used for regular color printing, such as tungsten lamps, mercury lamps,
Xenon lamps, laser beams, CRT beams, etc. can be used as light sources.

As the heating means, all methods applicable to ordinary heat-developable photosensitive materials can be used, such as contacting with a heated block or plate, contacting with a heated roller or drum, passing through a high-temperature atmosphere, etc. Alternatively, it is also possible to use high frequency heating, or furthermore, to provide a conductive layer in the photosensitive material of the present invention or in the image receiving member for thermal transfer, and to utilize Joule heat generated by electricity or a strong magnetic field. There are no particular restrictions on the heating pattern, including methods of preheating (preheating) and then reheating.
Continuous rise at high temperature for a short time or low temperature for a long time,
Although descending or repeated heating or even discontinuous heating is possible, a simple pattern is preferred. Alternatively, a method in which exposure and heating proceed simultaneously may be used.

When the heat-developable photosensitive material of the present invention is a black-and-white type that forms a silver image, the heat-developable photosensitive material is usually exposed at 80°C after imagewise exposure.
at a temperature range of ~250°C, preferably ioo°C ~ 200°C, for 1 second to 24081 seconds, preferably for 1.5 seconds to 1
Developed by heating for just 20 seconds. Moreover, you may perform preheating in the temperature range of 70 degreeC - 200 degreeC before exposure.

The heat-developable photosensitive material on which a silver image has been formed can be displayed and stored as is, but if a longer period of storage is required, unreacted silver salt is preferably removed.

Removal of unreacted silver salts can be carried out using bleach baths, fixing baths, or bleach-fixing baths (for example, JP-A-5
No. 0-54329, No. 50-77034@, No. 51-3
No. 28, processing of No. 51-80226, etc., JP-A-59
-136733, Research Disclosure No.
16407, same No. 16408, same No. 1
Bleach-fix sheets such as those described in US Pat. No. 6,414, may also be used.

In the case of a color type material using a dye-providing substance, the temperature is usually 80°C to 200°C so that the image receiving member described later and the photosensitive layer side of the photothermographic material of the present invention in the exposure flow are in a stacked relationship.
C., preferably in the temperature range of 120.degree. C. to 170.degree. C., by heating for 1 second to 180 seconds, preferably 1.5 seconds to 120 seconds, thereby transferring the image to the image receiving member at the same time as color development. Further, preheating may be performed at a temperature range of 70" to 180° C. before exposure.

The image receiving member used in the present invention only needs to have the function of receiving the dye released or formed by thermal development, and may be a mordant used in dye diffusion transfer type light-sensitive materials or JP-A-57-2
It is preferable to use a heat-resistant polymer material with a glass transition temperature of 40° C. or more and 250° C. or less, as described in US Pat. No. 07250@, etc.

Specific examples of the mordants include nitrogen-containing secondary and tertiary amines, nitrogen-containing heterocyclic compounds, quaternary cationic compounds thereof, U.S. Pat. Nos. 2,548,564 and 2,48
No. 4,430, No. 3,148,061, No. 3,756
, 814; vinylpyridine and vinylpyridinium cationic polymers disclosed in U.S. Patent No. 2,675,316; polymers containing dialkylamino groups disclosed in U.S. Pat. Aminoguanidine l! Conductor, Japanese Patent Publication No. 5
4-137333, U.S. Pat. Nos. 3,625,694, 3,859,
No. 096, British Patent No. 1,277.453, British Patent No. 2,0
No. 11,012, a mordant capable of crosslinking with gelatin, etc.; U.S. Pat. No. 3,958,995;
721,852 and 2,198.063, water-insoluble mordants disclosed in JP-A-50-61228, and U.S. Patent No. 3,788.
, No. 855, West German Patent Application (OLS) No. 2,843,3
No. 20, Japanese Patent Application Publication No. 1983. -30328, 52-155
No. 528, No. 53-125, No. 53-1024,
No. 54-74430, No. 54-124726, No. 5
No. 5-22768, U.S. Patent No. 3.642.482;
No. 3,488,706, No. 3,557,066, No. 3.271.147, No. 3,271,148, Special Publication No. 55-29418, No. 56-36414, No. 57
Various mordants disclosed in No. 12139, RD 12045 (1974) can be mentioned.

Particularly useful mordants are polymers containing ammonium salts,
A polymer containing quaternary amino groups as described in US Pat. No. 3,709,690. Examples of polymers containing ammonium salts include polystyrene-N,N,N-tri-0-hexyl-N-vinylbenzylammonium chloride, where the ratio of styrene and vinylbenzylammonium chloride is 1:4 to 4:1; Preferably the ratio is 1:1.

A typical image-receiving layer for dye diffusion transfer is obtained by coating a polymer containing an ammonium salt mixed with gelatin on a support.

Examples of the heat-resistant organic polymer substance include molecules l 2,
000 to 85,000 polystyrene, polystyrene derivatives with substituents having 4 or less carbon atoms, polyvinylcyclohexane, polyvinylbenzene, polyvinylpyrrolidone,
Polyacetals such as polyvinyl carbazole, polyallylbenzene, polyvinyl alcohol, polyvinyl formal and polyvinyl butyral, polyvinyl chloride,
Chlorinated polyethylene, polytrichloride fluoroethylene, polyacrylonitrile, poly N, N-dimethylacrylamide, polyacrylate with p-cyanophenyl group, pentachlorophenyl group and 2,4-dichlorophenyl group, polyacrylchloroacrylate, poly° Methyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polyisopropyl methacrylate, polyisobutyl methacrylate, poly tert-butyl methacrylate, polycyclohexyl methacrylate, polyethylene glycol dimethacrylate, poly-
Examples include polyesters such as 2-cyano-ethyl methacrylate and polyethylene terephthalate, polycarbonates such as polysulfone and bisphenol A polycarbonate, polyanhydrides, polyamides, and cellulose acetates. In addition, Polymer Handbook 2nd edition (Polymer Handbook
2nd ed, ), J, Bran
drup, E, )1. l merg
ut), John Wiley & Sons Publishing (J
Also useful are synthetic polymers with glass transition temperatures of 40° C. or higher, such as those described in W. Iley & Sons. These polymeric substances may be used alone or in combination of two or more as a copolymer.

Particularly useful polymers include cellulose acetates such as triacetate and diacetate; polyamides in combinations such as heptamethylene diamine and terephthalic acid; fluorene dipropylamine and adipic acid; hexamethylene diamine and diphenic acid; hexamethylene diamine and isophthalic acid; Polyester made from a combination of diethylene glycol and diphenylcarboxylic acid, bis-p-carboxyphenoxybutane and ethylene glycol, etc.
Examples include polyethylene terephthalate, polycarbonate, and vinyl chloride. These polymers may be modified. For example, polyethylene terephthalate using cyclohexane dimetatool, isophthalic acid, methoxypolyethylene glycol, 1,2-dicarbomethoxy4-benzenesulfonic acid, etc. as a modifier is also effective. Among these, particularly preferred are A made of polyvinyl chloride as described in Japanese Patent Application No. 58-97907, and A made of polycarbonate and a plasticizer as described in Japanese Patent Application No. 58-128600.

The above polymer is used by dissolving it in a suitable solvent and coating it on a support to form an image receiving layer, or by laminating a film-like image receiving layer made of the above polymer on a support, or by coating it on a support. It is also possible to constitute the image-receiving layer by a member (for example, a film) made of the above-mentioned polymer alone (also used as an image-receiving layer support).

Furthermore, the image-receiving layer may be constructed by providing an opaque layer (reflective layer) containing titanium dioxide or the like dispersed in gelatin on the image-receiving layer on a transparent support. This opaque layer provides a reflective color image when the transferred color image is viewed from the transparent support side of the image-receiving layer.

[Specific Examples of the Invention] Hereinafter, the present invention will be specifically explained using Examples, but the embodiments of the present invention are not limited to these.

Example 1 [Preparation of silver bromide emulsion] Silver bromide emulsion A for comparison was prepared by the following method. 5
At 0°C, JP-A-57-92523, JP-A-51-9
An aqueous solution containing 1.1 mol of potassium bromide in solution (A) prepared by dissolving ossein gelatin 20 () 1 1 distilled water 1000 d and ammonia using the mixer shown in the Memorandum No. 2524. 500.9 (B), an aqueous solution containing 1 mol of silver nitrate and ammonia (500112)
Solution C) was added at the same time while keeping the pAg constant. The shape and size of the emulsion grains to be prepared were adjusted by adjusting the addition rates of l) H, I) Ag, and solutions (B) and (C). A silver bromide emulsion was thus prepared.

The obtained silver halide grains were octahedral grains with an average grain size of 0.3 μl and a monodispersity of 8%.

This emulsion was washed with water and desalted. Emulsion yield is 8001fl
Met.

[Silver iodobromide emulsions made by vA] Silver halide emulsions B, C, D and E containing four types of photosensitive silver halides having different silver iodide contents were prepared by the following method.

At 50°C, JP-A-57-92523, JP-A-57-92523;
Using the mixing stirrer shown in the specification of No. 92524, add potassium iodide and potassium bromide to a solution (A) in which 20 g of ossein gelatin, too much distilled water (h12) and ammonia were dissolved (for emulsion B, add iodide to the solution (A)). Potassium 6.641;
l, potassium bromide 131 (1, for emulsion C, potassium iodide 11.6!I+, potassium bromide 131!I+,
For emulsion use: 19.9 g of potassium iodide, 1 g of potassium bromide
25g emulsion For daily use, solution (B) of aqueous solution 5001Q containing 33.21;l of potassium iodide and 119g of potassium bromide, solution (C) of solution 5001Q containing 1 mole of silver nitrate and ammonia, and solution (C) of 6 and 1) were added at the same time while keeping AC+ constant. The shape and size of the emulsion grains to be prepared were adjusted by controlling the HS EIA and the addition rate of Solutions B and C. In this way, emulsions having the same regular octahedral shape but different silver iodide contents were prepared.

(The monodispersity of each emulsion was 9%.) Each of these emulsions was washed with water and desalted.

The yield of each emulsion was 80 (h12).

The average grain size and silver iodide content of each comparative silver halide emulsion A to H prepared in this manner are shown in Table 1 below.

Twelve types of core/shell type emulsions F-Q having different silver iodide contents and average grain sizes were prepared by the following method.

At 50°C, JP-A-57-92523, JP-A-57-92523;
Potassium iodide and potassium bromide were added to the solution (A) in which 20 g of ossein geladine, 1000 g of distilled water, and ammonia were dissolved using the mixing agitator shown in Specification No. 92524 (for emulsion H, potassium iodide was added). 11.6g, potassium bromide 131Ω, potassium iodide 11.6Q, potassium bromide 131g for emulsion G, potassium iodide 11.6111, potassium bromide 131Q for emulsion H
.

For Emulsion H, potassium iodide 11.61J, potassium bromide 131g,
For emulsion Q, potassium iodide ii, eg, potassium bromide 131g; for emulsion, potassium iodide 11.6Q, potassium bromide 131g; for emulsion, potassium iodide 33.2Ω, potassium bromide 119g, emulsion M Potassium iodide 33.2 (J), potassium bromide 119 g.

For emulsion N Potassium iodide 33.2g, potassium bromide 119g.

For emulsion 0, potassium iodide 33.2g, potassium bromide 119i1
1.

(For Emulsion P, potassium iodide 33.2g, potassium bromide 119g; for Emulsion Q, potassium iodide 33.2Q, bromide, 119g)
Aqueous solution containing soo, 6 (B) solution and silver nitrate 1
500 tR of an aqueous solution containing mol and ammonia (
Solution C) was added at the same time while keeping DACI constant.

The shape and size of the particles of the core emulsion prepared by pH 1I)
It was adjusted by controlling the addition speed of A (J, solution (B), and solution (C). In this way, core emulsions with the same regular octahedral shape but different average grain sizes and silver iodide contents were prepared. (The monodispersity of each emulsion was 8%.) Next, using the silver halide grains obtained above as cores, the same method as above was used (however, each iodine of solution (B) Potassium iodide concentration and potassium bromide concentration for Emulsion H are potassium iodide Og., potassium bromide 131g, and Emulsion G.
Potassium iodide 3.32 G, potassium bromide 131 g,
For Emulsion H, 6.64 Q of potassium iodide, 131 g of potassium bromide,
For emulsion H, potassium iodide 9.96 G, potassium bromide 131Q,
For emulsion Q, potassium iodide 3.32 Q, potassium bromide 131 g,
For emulsion, potassium iodide 3.32 Q, potassium bromide 131 g,
Potassium iodide OQ, potassium bromide 131g for emulsion, potassium iodide 3.32 (], potassium bromide 131q for emulsion M)
, for emulsion N, potassium iodide 6.64 Q, potassium bromide 131 g,
For emulsion G, potassium iodide 9.96 (J, potassium bromide 131
g, potassium iodide 3.32 +7, potassium bromide 131 g for emulsion P
, Potassium iodide 3.32 G, Potassium bromide 1310 G for Emulsion Q
) and coated with a silver halide shell to prepare core/shell type silver halide emulsions having the same regular octahedral shape but different average grain sizes and silver iodide contents.

Each of these emulsions was washed with water and desalted.

The numerical value of each emulsion was 8001R.

The average grain size and silver iodide content of each of the core/shell type silver halide emulsions F to Q treated in this way are shown in Table 2 below.

Margin Table-2 Below Margin [Preparation of Organic Silver Salt Dispersion-1] Silver 5-methylbenzotriazole obtained by reacting 5-methylbenzotriazole and silver nitrate in a water-alcohol mixed solvent 28.8! J and poly(N-vinylpyrrolidone) 16. OQ and 4-sulfobenzotriazole sodium salt 1.330 were dispersed in an alumina ball mill to give pi-15,5 and 200112.

[Preparation of photosensitive silver halide dispersion] Each of the 17 silver halide emulsions A to Q prepared above was mixed with the following sensitizing dye (1) and 4-hydroxy-6-methyl-1,3,3a, Seventeen types of photosensitive silver halide dispersions A-Q having the following compositions were prepared by sulfur sensitization treatment with sodium thioTiAFa in the presence of 7-titrazyden.

Silver halide (in terms of silver) 381 g Gelatin gsg / 2820tR Sensitizing dye (1) [Preparation of dye-donor dispersion-1] Exemplary dye-donor substances o3S, 5Q and the following hydroquinone compounds s, oog were mixed with acetic acid nibbles. Dissolved in 200 i (
1, alkanol aqueous solution 12411I2, phenylcarbamoylated gelatin (Rouslow, type 178t9P C > 3o.
Gelatin aqueous solution 72 (h (l) containing 5 g was mixed with an ultrasonic homogenizer, ethyl acetate was distilled off, and then the gelatin solution was adjusted to H5.5 to obtain 795 ml).

Hydroquinone compound.

n/-/ [Preparation of reducing agent dispersion-1] Exemplary reducing agent (R-11) 23.3 (1), Development accelerators 1 and 10 (1) below, Poly(N-vinylpyrrolidone) 14.6 (] .

The following fluorine-based surfactant o. Dissolve sog in water and add 1
) H 5.5 and 250 yen.

Development accelerator surfactant and '7#,? 7=2 engineering r=+13) [Preparation of heat-developable photosensitive material-1] 12.5 nL of the organic silver salt dispersion-1 prepared above 6.00 nL each of the silver halide dispersions A-Q, dye donor 39.8d for substance dispersion-1, 12.5d for reducing agent dispersion-1
nN, and then a hardening agent solvent [tetra(vinylsulfonylmethyl)methane and taurine in a 1=1 (weight ratio)
and dissolved in a 1% aqueous solution of phenylcarbamoylated gelatin so that tetra(vinylsulfonylmethyl)methane was 3Ifffi%. ) to 2.5
0ue, polyethylene glycol 300 (as a heat solvent)
After adding 3.80Q of (manufactured by Kanto Kagaku Co., Ltd.), it was coated on a 180μ-thick photographic polyethylene terephthalate film that had been undercoated so that Silver 4 was 1.76a/f, and then A protective iJ layer made of a mixture of the phenylcarbamoylated gelatin and poly(N-vinylpyrrolidone) was provided.

[Preparation of image receiving member-1] Polyvinyl chloride (n=1.10
0. Apply Tetrahydrofuran solution (Wako Pure Chemical),
The polyvinyl chloride was adjusted to 12 Q/f.

The photothermographic material was exposed to 1,600 C, M, and S through a step wedge, and then combined with the image receiving member in a heat developing machine (developer module 277).
．． After heat development was carried out at 150°C for 1 minute at 3M Co., Ltd., the photothermographic material and the image receiving member were quickly peeled off, and a magenta step wedge negative image was obtained on the polyvinyl chloride surface of the image receiving member. It was done.

The anti-tA11 degree of the obtained negative image was measured using a densitometer (PDA-65
Relative sensitivity and minimum density (fog) were measured. The results are shown in Table 3 below.

However, in Table 3, the relative sensitivity is the reciprocal of the exposure amount that gives a fog of +0.3, and is a relative value with the sensitivity of sample-1 set as 100.

As is clear from the results in Margin Table 3 below, silver halide containing core/shell type silver halide grains of the present invention compared to samples (No, 1 to 5) using comparative silver halide emulsions. Samples of heat-developable photosensitive materials using emulsions (No. 6 to 1)
It can be seen that Sample No. 7) has good characteristics with improved photographic sensitivity and fog.

Example 2 Silver halide emulsion A-Q prepared in Example 1 was treated with the following sensitizing dye (2) and 4-hydroxy-6-methyl-1.
, 3,3a,7-thitrazaindene was subjected to sulfur sensitization treatment with sodium diosulfate to obtain 17 with the following composition.
Separate photosensitive silver halide dispersions A' to Q' were prepared.

Sensitizing dye (2) Silver halide (converted to silver) 381g Gelatin 85 (7/282016 [
Preparation of dye-providing substance dispersion-2] Exemplary dye-providing substance ■30. OQ of tricresyl phosphate 30. o(+ and ethyl acetate 90.OtQ, mixed with gelatin aqueous solution 4601Q containing a surfactant, same as in Example-1, dispersed with an ultrasonic homogenizer, ethyl acetate was distilled off, and water was added. Soo, I set it to 1.

[Preparation of heat-developable photosensitive material-2] 4 of each of the 17 types of silver halide dispersions A' to Q'
0.0t12, 25 of organic silver salt dispersion-1 of Example-1
．． 01Q, SQ of dye-providing substance dispersion-2, (ha12
and polyethylene glycol 300 (manufactured by Kanto Kagaku Co., Ltd.) as a hot solvent. Hardener 3
．． 10% by weight water-alcoholic solution of OOmQ and guanidine trichloroacetic acid20. (hR was added and coated on an undercoated photographic poly-1-ethylene terephthalate film having a thickness of 180 μm so that the amount of silver was 2.50 M12.

[Preparation of Image Receiving Member-2] The following layers were sequentially coated on a 100 μm thick transparent polyethylene terephthalate film.

(1) Layer made of polyacrylic acid. (7,OOa/f)
(2) A layer consisting of cellulose acetate. (4,OOa/f)
(3) Styrene and N-benzyl-N, N-dimethyl-N
- a layer consisting of a 1=1 copolymer of (3-maleimidopropyl)ammonium chloride and gelatin.

(Copolymer 3.OOQ/f, gelatin 3.00g/7
) The heat-developable photosensitive material-2 was exposed to 1,600 C, M, S through a step wedge;
After heating for 1 minute on a heat block at 50° C., the image receiving member-2 immersed in water was bonded and heated at 50° C., 500 g ~
800 (1/C1') was crimped for 30 seconds and then quickly peeled off.The transmission density of the yellow transparent image obtained on the surface of the image receiving member was measured using a densitometer (PDA-65, manufactured by Konishiroku Photo Industry Co., Ltd.). The relative sensitivity and minimum density (fog) were measured.The results are shown in Table 4 below.

However, in Table 4, the relative sensitivity is the reciprocal of the exposure that gives fog +0.3, and is a relative value with the sensitivity of sample 18 as 100.

As is clear from the results in Margin Table 4 below, compared to the samples (No. 18 to 22) using comparative silver halide emulsions, the silver halide containing the core/shell type silver halide grains of the present invention Samples of heat-developable photosensitive materials using emulsions (No. 23-3)
It can be seen that sample 4) has good characteristics with improved photographic sensitivity and fog.

Patent Applicant Roku Konishi Photo Industry Co., Ltd. Tewan 111J-Fr ((self-R) December 5, 1985 Patent Application No. 215948 2, Name of Invention Heat-developable Photosensitive Material 3, Amendment Relationship with Special W [Applicant Address: 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(127) Representative Director of Konishiroku Photo Industry Co., Ltd.
11,000 Keio 4, Agent 102 Address Chiyo, Tokyo [■ Kudan Kita 4-1-1 Kudan-
Rosaka Building Telephone: 263-9524 Column 6 of ``3. Detailed Description of the Invention'' in all the contents of the amendment The detailed description of the invention is summarized as follows.

(1) Change the statement "...5-me1 to 4=silver dibenzotriazole, silver 4-sullebobenzotriazole,..." in lines 3 to 5 of page 22 of Mei III to [...5 -Methoxybenzotriazole silver, 5-methylbenzotriazole silver, 4-sulfobenzotriazole silver, ...'' is corrected.

(2) On page 23 of the specification box, lines 3-4, "...more preferably a silver salt of a sulfobenzo-1-lyazole derivative..."
ffJ llnib. ``...More preferably silver salts of methylbenzotriazole derivatives and sulfobenzo-1 heliazole derivatives...''.

(3) The statement "...hardener solvent..." in line 6 from the bottom of No. 90 of the specification is corrected to "...hardener solution...".

that's all

Claims (1)

[Claims] The photosensitive silver halide emulsion of the heat-developable photosensitive material is a photosensitive silver halide grain having a silver iodide content of 4 to 40 mol %, and the core/silver iodide content in the surface layer of the grain is lower than that in the inner layer. A heat-developable photosensitive material characterized by containing shell-type photosensitive silver halide grains.