JPS62103634A - Heat developable photosensitive material - Google Patents

Abstract

PURPOSE:To form a heat developable photosensitive material which decreases thermal fogging and has high sensitivity by incorporating core/shell type photosensitive silver halide particles and two kinds of specific compds. into a silver halide emulsion layer. CONSTITUTION:This photosensitive material contains the core/shell type photosensitive silver halide particles contg. 4-40mol% silver iodide and the compds. expressed by formula I and formula II into the silver halide emulsion layer formed on a base. In formula I, R1 denotes a halogen atom, etc., R3, R3 denote a hydrogen atom or protective group which desorps by decomposition. n Denotes 1-4 integer. In formula II, R4 denotes a hydrogen atom, etc., R5 denotes a hydrogen atom, etc., and X denotes (R5)2 or atomic group necessary for forming a carbon ring. However, R5 may be the same or different if X is (R5)2. R6 denotes a hydrogen atom or protective group which desorps by decomposition, R7 denotes a group of >=7 total sum of C, m denotes 0-2 integer, and m1 denotes 0 or 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a heat-developable photosensitive material. More specifically, the present invention relates to a heat-developable photosensitive material with a small thermal capri and high sensitivity during heat development.

[Background of the Invention The method of developing photosensitive silver halide photosensitive materials by dry heat treatment has many advantages over the conventional wet method using a developing solution in terms of processing time, cost, and concerns about pollution. are doing. Therefore, regarding such heat development, for example, Japanese Patent Publications No. 43-49214 and No. 43-49
No. 24 discloses a black-and-white photothermographic material comprising silver halide, a reducing agent, and an organic silver salt.

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. 57-2072
No. 50, No. 58-40551, No. 58-58543, No. 5g-79247, No. 59-12431, No. 59-22049, No. 59-68730, No. 59-
No. 124339, No. 59-124333, No. 59-1
No. 24331, No. 59-159159, No. 59-18
No. 1345, No. 59-159161, No. 58-116
No. 537, No. 5g-123533, No. 58-14
There are No. 9046 and No. 58-14947.

The basic composition of a color type heat-developable photosensitive material for obtaining color images consists of a photosensitive element and an image-receiving element, and the photosensitive element basically consists of a photosensitive silver halide, an organic silver salt, a reducing agent, a dye-donating substance, It consists of 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 in heat development,
Dissolution physical development according to optical information is performed between the organic silver salt and photosensitive silver halide under the action of a reducing agent, and the reducing agent that has acted or has not acted reacts with the dye-donating substance. , in which dyes forming an image are released or formed. The image-forming dye obtained by thermal development is transferred to an image-receiving element to form an image.

In the black-and-white type photothermographic materials and color type photothermographic materials in which silver images are formed, images are usually formed by thermal development after exposure or simultaneously with exposure.

In recent years, LEDs have been used as a lighting means for heat-developable photosensitive materials.
, CRT, FOT, semiconductor laser, and other light sources that use low-intensity exposure have come to be used.

On the other hand, there has been a demand for a reduction in the time required to obtain an image, and in particular, for heat-developable photosensitive materials, there is a need to shorten the exposure time for rapid processing photosensitive materials, that is, to increase the sensitivity of photosensitive silver halide. There is a strong desire for this to become a reality.

In the photosensitive silver halide of heat-developable photosensitive materials, the sensitivity of the silver halide is increased by adjusting the particle size distribution of the silver halide grains and increasing the silver iodide content in the silver halide. There is.

However, in heat-developable photosensitive materials in which the silver iodide content in silver halide is increased, there is a problem in that thermal capri increases during thermal development.

In response, many thermal fog preventive agents have been proposed that reduce thermal capri. For example, U.S. Patent No. 3,58
Mercury compound of No. 9,903, West German Patent No. 2,402.1
N-halogeno compound of No. 61, No. 2,500,508
peroxides in US Pat. No. 2,617,907, palladium compounds in US Pat. No. 4,102,312, sulfine MM in US Pat. 1
69079, Mercaptotriazole, U.S. Pat.
1°2,4-triazole of No. 137,079 and the like.

However, these thermal antifoggants have disadvantages in that they are extremely harmful to the human body and have a small antifogging effect on silver halide grains with a high silver iodide content.

In view of the above-mentioned problems, the present inventors conducted extensive research and found that an emulsion consisting of core/shell type photosensitive silver halide grains with a silver iodide content within a specific range contains a specified compound. The inventors have discovered that by doing so, high sensitivity and improved thermal coupling can be achieved, leading to the present invention.

[Object of the Invention] An object of the present invention is to provide a heat-developable photosensitive material with a small thermal capri and high sensitivity.

r, Constitution of the Invention j The above object of the present invention is to provide a core/shell type photosensitive halogenated material having a silver iodide content of 4 to 40 mol% in at least one of the silver halide emulsion layers on the support. Silver particles, a compound represented by the following general formula [1] and the following general formula [
This is achieved by a heat-developable photosensitive material containing at least one compound selected from the compounds represented by [II].

In the formula, R1 is a halogen atom, an alkyl group, an aryl group,
Acyl group, alkyloxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, alkylamino L arylamino group, carbamoyl group, acylamino group, alkoxy group, sulfamoyl group, alkylsulfonylamino group, arylsulfonylamino LL sulfonic acid represents a group or a salt thereof, a carboxylic acid group or a salt thereof, a nitro group or a human Oxyl group. R2 and R3 represent a hydrogen atom or a protecting group that is removed by decomposition. n represents an integer from 1 to 4.

In the formula, R4 represents a hydrogen atom, an alkyl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkylaminesulfonyl group, or an arylaminosulfonyl group, and %R5 represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or an alkoxy group. , represents an acylamino group or a sulfamoyl group, and X represents (R5)2 or an atomic group necessary to form a carbon ring.However, when X is (R5)2, R5 may be the same or different.

R6 represents a hydrogen atom or a conservation group that decomposes and leaves,
R7 represents a group having a total number of carbon atoms of 7 or more, and m is O~2
The integer ml represents 0 or 1.

[Specific Structure of the Invention] In the present invention, compounds represented by the general formula [I] and the general formula rlI] (hereinafter referred to as the hydroxybenzene derivative of the present invention) are used.

In the general formula [I], R1 is a halogen atom (preferably a chlorine atom, a bromine atom, or an iodine atom) or an alkyl group (preferably an alkyl group having 1 to 24 carbon atoms, such as methyl, ethyl , butyl, t-amyl, t-
Examples include groups such as octyl, n-dodecyl, n-pentadecyl, heptadecyl, octadecyl, and cyclohexyl. Furthermore, the alkyl group substituted with an aryl group, for example a phenyl group, may be a benzyl group or a netethyl group. ), aryl groups (e.g. phenyl, naphthyl, tolyl, mesityl), acyl groups (
For example, acetyl group, tetradecanoyl group, pivaloyl group, substituted or unsubstituted benzoyl group), alkyloxycarbonyl group (e.g. methoxycarbonyl group, benzyloxycarbonyl group), aryloxycarbonyl group (e.g. phenoxycarbonyl group, p- tolyloxycarbonyl group, α-naphthoxycarbonyl group), alkylsulfonyl group (e.g. methylsulfonyl group), arylsulfonyl group (e.g. phenylsulfonyl group, alkylphenylsulfonyl group,) alkylamino M (e.g. ethylamino group, t-octyl group) (amino group), arylamino group (e.g. anilino group, or anilino group substituted with a substituent such as a halogen atom, alkyl group, amide group or imido group), carbamoyl group (e.g. M-substituted or unsubstituted alkylcarbamoyl group, Methylcarbamoyl group, butylcarbamoyl group, tetradecylcarbamoylsilcarbamoyl group, optionally substituted phenoxyalkylcarbamoyl group, specifically 2,4-di-t-phenoxybutyl-carbamoyl group, substituted or unsubstituted phenylcarbamoyl group , specifically 2-dodecyloxyphenylcarbamoyl group, etc.), acylamino group (e.g. n-butylamide group, laurylamide group, optionally substituted β-phenoxyethylamide group, phenoxyacetamide group, substituted or unsubstituted benzamide) group, methanesulfonamidoethylamide group, β-methoxyethylamide group, etc.), alkoxy group (preferably 1 to 1 carbon atoms)
18 alkoxy groups, such as methoxy groups, ethoxy groups,
octadecyloxy group, etc.), sulfamoyl group (e.g. methylsulfamoyl group, n-dodecylsulfamoyl group, substituted or unsubstituted phenylsulfamoyl group, specifically dodecylphenylsulfamoyl group, etc.),
It represents an alkylsulfonylamino group (eg, methylsulfonylamino group), an arylsulfonylamino group (eg, tolylsulfonylamino group), a sulfonic acid group or its salt, a carboxylic acid group or its salt, a nitro group, or a hydroxyl group.

Further, R1 may combine with each other to form a saturated or unsaturated 5- to 6-membered ring.

R2 and R3 are hydrogen atoms or holding groups that decompose and leave (
Preferably, it can be released under alkaline conditions.

Here, R8 to R13 each represent an alkyl group, a cycloalkyl group, an alkenyl group, or an aryl group (which may be substituted with a halogen atom such as chlorine, bromine, or fluorine). n represents an integer from 1 to 4.

Exemplary compounds of the compound represented by the general formula [I] are shown below, but the hydroxybenzene derivative of the present invention is not limited thereto.

Exemplary compound of general formula [I] Space below H (r-16) H (r -19) H (knee 13) (knee + q) (I-21 oH rI-22) (knee 24) l4 (T-- 27) oH O) ((I-2'l) oH (knee 3o) 0 month (knee 31) oH oH (1-?2) Oto1 (cho-3?nshirisushi, 2t125 The above general formula [ (2), where R% represents a hydrogen atom, an alkyl group (e.g. methyl group, i-propyl group, n-pentadecyl group, trifluoromethyl group, etc.), an aryl group (
For example, phenyl group, tolyl group, naphthyl group, etc.), acyl group (e.g. octylcarbonyl group, trifluoromethylcarbonyl group, acetyl group, stearoyl group, cyclohexanecarbonyl group, tricarbonyl group, etc.), alkylsulfonyl group (e.g. methylsulfonyl group), arylsulfonyl group (e.g. phenylsulfonyl group, o-tolylsulfonyl group, p-dodecyloxyphenylsulfonyl group, etc.), alkylaminosulfonyl group (e.g. ethylaminosulfonyl group, propylaminosulfonyl group, t-octylaminosulfonyl group, etc.), arylaminosulfonyl group (eg, anilinosulfonyl group, etc.).

R- is a hydrogen atom, a halogen atom (preferably a chlorine atom, a bromine atom, an iodine atom), an alkyl group (preferably an alkyl group having 1 to 24 carbon atoms, such as methyl, ethyl, butyl, t-amyl, Groups such as t-octyl, n-dodecyl, n-pentadecyl, and cyclohexyl can be mentioned, but further examples of alkyl groups substituted with aryl groups, such as phenyl groups, include benzyl groups and phenethyl groups.) Aryl groups (e.g., phenyl group, naphthyl group, tolyl group, medicyl group, etc.), alkoxy groups (e.g., methoxy group, benzyloxy group, etc.), acetamide L (e.g., n-butylamide group, laurylamide group, even if substituted) β-phenoxyethylamide group, phenoxyacetamide group, substituted or unsubstituted benzamide group, methanesulfonamidoethylamide group, β-methoxyethylamide group), or sulfamoyl group (e.g. methylsulfamoyl group, n-dodecyl group) It represents an alkylsulfamoyl group such as a sulfamoyl group, a substituted or unsubstituted phenylsulfamoyl group, specifically an arylsulfamoyl group such as a dodecylphenylsulfamoyl group.) R6 is a hydrogen atom or This represents a protecting group that decomposes and leaves, but examples of protective groups that decompose and leave include the same groups as the protecting groups that decompose and leave as represented by R2 and R3 in the general formula [IF]. .

X represents (R5)2 or an atomic group necessary to form a fused carbon ring, and when X is (R5)2, R5 may be the same or different.

R7 represents a group having a total number of carbon atoms of 7 or more (eg, n-hebutyl group, tolyl group, t-pentadecyl group, etc.).

m represents an integer from O to 2, and m7 represents O or 1, respectively.

Specific examples of the hydroxybenzene derivative represented by the general formula [II] of the present invention are shown below.

The present invention is not limited thereto.

Illustrative compounds of general formula (X-14) (x-+7) (M -+2) (π-lsuH'' HC2Hr The synthesis of the hydroxybenzene derivative of the present invention represented by the general formula [I] or [Ir] is carried out using the mesogen der organitsien Kemie (Huibenbeil) band
Methoden der 0ra
anishen Chemie (Houben-W
eVI) Band Vl /1 CPhenole
Te1l 1 (George Thieme V
erla (1, Stuttgard, published in 1976)
U.S. Patent No. 4.205.987, No. 4,447,
Specification No. 523, JP-A-59-188G4G@, JP-A No. 59
-192246, 59-192247, 59-
No. 195238, No. 59-195239, No. 59-2
No. 02465, No. 59-204039, No. 59-20
This can be carried out according to the methods described in No. 4040, No. 59-232341, and the like.

The additive of the hydroxybenzene derivative of the present invention is used in various concentrations depending on the purpose of use of the light-sensitive material, the type of dye-providing substance used, the location of addition, and heat development processing factors, but generally it is used in various concentrations. The silver halide to be used is 0.001 mol to 0.5 mol per 1°C, preferably o
, in the range of oos mol to 0.2 mol.

The hydroxybenzene derivative of the present invention can be added to at least one of the silver halide emulsion layers containing photosensitive silver halide in the heat-developable photosensitive material of the present invention. The hydroxybenzene derivative of the present invention may be added alone or 2N! The above may be used in combination. Furthermore, one or more hydroquinone compounds or precursors thereof other than those of the present invention may be used in combination.

Such a method provides the effect of improving the dispersion stability of the hydroxybenzene derivative of the present invention.

The hydroxybenzene derivative of the present invention can be added to the silver halide emulsion layer of a photothermographic material by dispersing it in a hydrophilic colloid. As these dispersion methods, known methods are used, and for example, the methods described below are useful.

(2) A method in which the hydroxybenzene derivative of the present invention is dissolved in a substantially water-insoluble high-boiling solvent and finely dispersed in a hydrophilic protective colloid.

Particularly useful high boiling solvents include N-n-butylacetanilide, diethyl lauramide, dibutyl lauramide,
Dibutyl phthalate, tricresyl phosphate, N-
Examples include dodecylpyrrolidone.

A low boiling point solvent or an organic solvent easily soluble in water can be used to aid in the dissolution.

Examples of low boiling point solvents include ethyl acetate, methyl acetate, cyclohexanone, acetone, methanol, ethanol, and
-Rahydrofuran, etc. Also, as the organic solvent that is not easily soluble in water, 2-methoxyethanol, dimethylformamide, etc. can be used. These low boiling point solvents and organic solvents that are easily soluble in water can be removed by washing with water, coating and drying, or the like.

■ Gradually adding a fillable polymer latex to a solution of the hydroxybenzene derivative of the present invention dissolved in a water-miscible solvent and enough water to make the hydroxybenzene derivative of the present invention in the solution insoluble. A method of incorporating said hydroquinone and/or its precursor into fillable polymer latex particles by.

The water-miscible organic solvent and the fillable polymer latex are described in JP-A-51-59942 and JP-A-51-59942.
It is described in detail in Japanese Patent No. 1-59943.

(2) A method in which the hydroxybenzene derivative of the present invention is mechanically made into fine particles using a sand grinder, a colloid mill, etc., and then dispersed in a hydrophilic colloid.

In the present invention, various methods can be arbitrarily used without being limited to the above methods.

The photosensitive silver halide grains used in the heat-developable photosensitive material of the present invention have a silver iodide content of 4 mol% to 40 mol%, more preferably a silver iodide content of 4 mol% to 20 mol%.
It is mole%.

When the silver iodide content exceeds the range of 4 mol % to 40 mol %, if the silver iodide content is less than 4 mol %, there will be little thermal fog, but disadvantages such as low photographic sensitivity will appear; If the silver iodide content in the silver halide grains exceeds mol %, disadvantages such as difficulty in obtaining uniform crystals and large thermal fog will appear.

The average grain size of the photosensitive silver halide grains used in the present invention is preferably 0.01 .mu.m to 0.4 .mu.m, more preferably 0.05 .mu.m to 0.4 .mu.m.

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 7 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. Typical methods include Loveround's "Particle Size Analysis!, JAS, T, M, Symposium
On Right Microscopy, 1955, 94-
122 or Chapter 2 of "Theory of Photographic Processes" by Mies and James, 3rd edition, published by Macmillan Publishing Co., Ltd. (1966). 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.

In the photosensitive silver halide grains used in the present invention,
There are no particular restrictions on other silver halide components in the photosensitive silver halide containing silver iodide, but preferred silver halide components are silver iodo-bromide and silver chloroiodobromide.

The photosensitive silver halide used in the present invention is described in "Himy et Physique Photographic" by P. Gerafkides (published by Ball Montell) (p, Qlafki
Des, Chimie et physique
photographique, paul
Montel) (1967) Young G.F. Duffin, Photographic Emulsion Chemistry (published by The Focal Press) (G, F,
Duffin, PhotoaraphicEmu
lsion Chemistry, The l”
(1966), Making and Coating Photographic Emulsions (The Focal Press) (V, L, Zelikman)
etal, Makingand Coatino
P photooraphic E mulsion
, The Focal Press) (1
964) 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 a back mixing method in which silver halide grains are formed in an excess of silver ions. Same rR
One of the mixing methods is to use the Condrold double-jet method in which silver halide is produced by arbitrarily controlling the Ag content in the solution in the reaction vessel and controlling the amount of silver and halogen solution added. According to this method, a so-called monodisperse silver halide emulsion in which the side crystal shapes and grain sizes of the silver halide grains are nearly uniform can be obtained.

In the present invention, the above-mentioned monodisperse silver halide emulsion means that the grain size distribution of the silver halide grains contained in the emulsion has a particle size distribution in which the variation in grain size is less than a certain proportion of the average grain size as shown below. refers to what one has. The grain size distribution of a photosensitive silver halide emulsion (hereinafter referred to as a monodisperse emulsion), which is composed 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 has a distribution width of 10% or less.

A more preferred photosensitive silver halide used in the present invention is a core/shell type having a surface latent image type shell.

The core/shell type photosensitive silver halide emulsion which is more preferably used in the present invention can be manufactured by VJ manufacturing 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 a double jet method while keeping pAg constant. Furthermore, the method described in JP-A-54-48521 can be applied to silver halide emulsions containing photosensitive silver halide having a monodispersity of 8 degrees. In a preferred embodiment of the method, a potassium iodobromide-gelatin aqueous solution and an ammoniacal silver halide aqueous solution are added to an aqueous gelatin solution to whiten silver halide seed grains, and the rate of addition is set at a rate of g of time. It is manufactured by a method in which the number of liters is varied and added. At this time, a silver halide emulsion containing highly monodisperse silver halide powder for the core can be obtained by appropriately adjusting the addition rate as a function of time, pH, pA9, temperature, etc.

By sequentially growing shells according to the manufacturing method of monodisperse emulsion using monodisperse core particles as described above,
A silver halide emulsion containing monodisperse core/shell type photosensitive silver halide which is more preferably used in the present invention can be obtained.

In the core/shell type photosensitive silver halide which is more preferably used in the present invention, the thickness of the shell cuffing the core is preferably 0.05% to 90% of the silver halide grain size, more preferably 1% to 90%. It is in the range of 80%. In the silver halide composition of the core, the silver iodide content is 4 mol% to 2
The silver iodide content is preferably 0 mol %, and in the halide m composition of the shell, the silver iodide content is preferably 0 mol % to 6 mol %.

More preferably, it is a core/shell type silver halide in which the silver iodide content in the core is 2 mol % or more higher than the silver iodide content in the shell.

The light-sensitive silver halide emulsion containing the light-sensitive silver halide grains of the present invention may be chemically sensitized by any method in the photographic art. 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 grains, a photosensitive silver salt-forming component may be allowed to coexist with an organic silver salt described below, and photosensitive silver halide may be formed in a part of the organic silver salt. can. The photosensitive silver salt-forming components used in this preparation method include inorganic halides, for example, halides represented by MXn (where M is an H atom, NH4
Represents W or a metal atom, and X is C2, [3r or ■
When M is an H atom or an N84 group, n represents 1, and when M is a metal atom, n represents its valence. Metal atoms include lithium, sodium, potassium, rubidium, cesium, copper, gold, beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, mercury, aluminum, indium, lanthanum, ruthenium, thallium, germanium, tin, and lead. , antimony, bismuth,
Chromium, molybdenum, tungsten, manganese, rhenium, iron, cobalt, nickel, rhodium, palladium,
Examples include osmium, iridium, platinum, and cerium. ), halogen-containing metal complexes (e.g.

K2 Pt C1s, Ni2 Pt Br6 HAtl
CIl+(N+-14>21r Cl1s, (NH4
)31r Cff1s(NH4)2 RU Cl1s,
(NHq)3 Ru C4!5(NH4)2 Rh
C16, (NH4)a Rh [3rs, etc.), onium halides (e.g., tetramethylammonium bromide, trimethylphenylammonium bromide, cetylethyldimethylammonium bromide, 3-methylthiazolium bromide, trimethylbenzylammonium bromide, etc.), 4 class ammonium halide,
tertiary sulfonium halides such as benzylethylmethylsulfonium bromide, zolium bromide, etc.), halogenated hydrocarbons (e.g., iodopol\,
bromoform, carbon tetrabromide, 2-bromo-2-methylpropane, etc.), N-halogen compounds (N-chlorosuccinimide, N-bromosuccinimide, N-bromophthalimide, N-bromoacetamide, N-iodosuccinic acid) Imide, N-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 photosensitive silver halide grains can be used in combination in a variety of methods, and the amounts used range from 112 to 0.00 per layer. It is preferably from ooig to 50g, more preferably from 0.1g to 10g.

The heat-developable photosensitive material of the present invention has a core/silver iodide content of 4 to 10 mol % in the silver halide emulsion layer as described above.
It is characterized by containing shell-type photosensitive silver halide grains and at least one compound of the present invention.

The heat-developable photosensitive material of the present invention has a multi-layer structure including a heat-developable blue-sensitive layer, a heat-developable green-sensitive layer, and a heat-developable photosensitive material. You can also do it. Further, the photosensitive material of the same color can be divided into two or more layers (for example, a high-sensitivity layer and a low-sensitivity layer).

In the above cases, the blue-sensitive silver halide emulsion, green-sensitive silver halide emulsion, and red-sensitive silver halide emulsion used respectively can be prepared by adding various spectral sensitizing dyes to the silver halide emulsion. It can be optically spectral sensitized to the wavelength range of -.

Typical spectral sensitizing dyes used in the present invention include, for example, cyanine, merocyanine, complex (trinuclear or tetranuclear) cyanine, holopolar cyanine, styryl, hemicyanine, A-xonol, and the like. Among the cyanine dyes, those having a basic nucleus such as buazoline, oxazoline, pyrroline, pyridine, oxazole, thiazole, selenazole, and imidazole are more preferred. Such nuclei include alkyl groups, alkylene groups,
It may contain a hydroxyalkyl group, a sulfoalkyl group, a carboxyalkyl group, an aminoalkyl group or an enamine group capable of forming a 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 Ju l': fj nucleus described above, merocyanine dyes have acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidione nucleus, thiazolidinedione nucleus, barbituric acid nucleus, thiazolindione nucleus, malononitrile nucleus, and pyrazolone nucleus. You may do so.

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 u1 alkylamine group or a peterocyclic nucleus (1).

If necessary, these dyes may be used in combination. Furthermore, ascorbic 11Q (i-conductor, azaindene cadmium salt, organic sulfonic acid, etc., such as U.S. Pat. No. 2
, No. 933,390, and No. 2.937,089.
A supersensitizing additive that does not absorb visible light, such as those described in Section s, etc., can be used in combination.

The amount of these sensitizing dyes added is from 1.times.10@-4 mol to 1 mol per mol of photosensitive silver halide. More preferably l is 1,1 x 10-4 mol - 1 x 10-' mol.

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

For example, there are black-and-white types that form a silver color by heat development, and color types that include a dye-providing substance. In this latter color type, further monochromatic, e.g., monochrome, with a black dye-donor or any other monochromatic dye-donor; polychromatic, e.g.
Examples include yellow, cyan and magenta pigmented silver heat-developable color photosensitive materials. In color types, for example, cyan dyes are usually obtained from a cyan dye-providing substance in a red-sensitized emulsion layer, magenta dyes are obtained from a magenta dye-providing substance in a green-sensitized emulsion layer, and yellow dyes are obtained from a magenta dye-providing substance in a green-sensitized emulsion layer. A method is used in which only a dye developed from a yellow dye-providing substance in a blue-sensitized emulsion layer is transferred to an 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, which is basically a silver halide emulsion layer on a support, contains (1) photosensitive silver halide, (2)
reducing agent, (3) binder, and optionally (4)
Contains organic silver salt.

In addition, in the color type for forming a Buddhist image, the photosensitive layer, which is basically one silver halide emulsion layer on the support, contains (1) photosensitive silver halide, (2) reducing agent, (
3) a binder, (5) a dye-providing substance, and (4) an organic silver salt if necessary. 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, (1), (2), (3), and (4).
) is contained in one photosensitive layer and the dye-providing substance (5) is contained in the other layer adjacent to this photosensitive layer. It may also be included.

Furthermore, the photosensitive layer may be divided into two or more layers, such as a high-sensitivity layer and a low-sensitivity i-layer, and may further include one or more other photosensitive layers having different color sensitivities. Alternatively, it may have various constituent layers such as an overcoat layer, an undercoat layer, a backing layer, and an intermediate layer.

Similar to the heat-developable photosensitive layer of the present invention, coating solutions are prepared for the protective layer, intermediate layer, undercoat layer, back layer, and other rotational constituent layers, and coated using the dipping method, air knife method, curtain coating method, or coating method. The photothermographic material can be prepared by various coating methods such as the hopper coating method described in US Pat. No. 3,681,294.

Additionally, if desired, 2vI or EL can be applied quantitatively 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 rotational constituent layers of the heat-developable photosensitive material of the present invention are coated on a support, and the thickness of the coating after drying is preferably 1 to 1,000 μm, more preferably 3 μm. It is ~20μ.

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 Publication No. 43-4921, Japanese Patent Publication No. 44-26582, Japanese Patent Publication No. 45-18416, Japanese Patent Publication No. 45-12700, Japanese Patent Publication No. 45-12700,
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 red stamp patent No. 3,330,6
No. 33, No. 3,794,496, No. 4,105,
No. 451, No. 4,123.274, No. 4.168
．． No. 980, etc., [Silver salts of aliphatic carboxylic acids such as silver laurate, silver myristate, silver valmitate, silver stearate, silver arachidonate, silver behenate, α -(1-Phenyltetrazolethio) silver aromatic carboxylates such as silver acetate, such as silver benzoate, silver phthalate, etc., Japanese Patent Publication No. 44-26582, No. 4
No. 5-12700, No. 45-18416, No. 45-2
No. 2185, JP-A-52-31728, JP-A No. 52-13
No. 7321, JP-A No. 58-118638, 5g-1
Silver salts of imino groups such as those described in publications such as No. 18639, such as silver benzotriazole, silver 5-nitrobenzotriazole, silver 5-chlorobenzotriazole, silver 5-methoxybenzotriazole, and 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
-Tetrazole silver, 3-amino-5-benzylthio-
1,2,4-F-lyazole silver, saccharin silver, phthalazinone silver, phthalimide silver, etc., 2-mercaptobenzoxazole silver, mercaptooxadiazole silver, 2-mercaptobenzothiazole silver, 2-mercaptobenzimidazole silver, 3 -Mercapto-4-phenyl-1,2,4-triazole silver, 4-hydroxy-6-
Methyl-1,3,3a, 7-titrazaindene silver, 5-methyl-7-hydroxy-1,2,3,4,6-pentazaindene silver, and the like. Among the above-mentioned 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 to be 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 heat-developable photosensitive material of the present invention, those commonly used in the field of heat-developable photosensitive materials can be used. For example, U.S. Pat.
761,270, 3,764,328, and RD No. 12146, RD No. 0.1510
8. Same No.

15127 and JP-A No. 56-27132, p-phenylenediamine type and p-ruaminophenol developing agents, phosphoramide phenol type and sulfonamide phenol type developing agents, and hydrazone type color developing agents. 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 advantageously 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 R2 represent a hydrogen atom or an alkyl group having 1 to 30 carbon atoms (preferably 1 to 4) which may have a substituent, and R' and R2 are The ring may be closed to form a heterocycle. R3, RQ-R9 and R6 each have a hydrogen atom, a halogen atom, a hydroxy group, an amine group, an alkoxy group, an acylamido group, a sulfonamide group, an alkylsulfonamide group, or a carbon atom number of 1 to 30 that may have a substituent ( Preferably represents an alkyl group of 1 to 4),
R3 and R' and R' and R2 may each be ring-closed to form a heterocycle. M represents an alkali metal atom, an ammonium group, a nitrogen-containing organic base, or a compound containing a quaternary nitrogen atom.

The nitrogen-containing organic base in the above general formula (1) is an organic compound containing a basic nitrogen atom capable of forming a salt with non-purulent acid, and particularly important organic bases include amine compounds. Chain amine compounds include primary amines, secondary amines, tertiary amines, etc., and cyclic amine compounds include lysine, quinoline, piperidine, etc., 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. As the salt of the nitrogen-containing base, inorganic acid salts of the above-mentioned rA bases (eg, hydrochloride, sulfate, nitrate, 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 (1) are shown below.

(R-1) (R-2) (R-3) (R-4) F3 (R-5) , (R-6) (R-7) (R-8) (R-9) H3 (R -10) (R-11) (R-12) (R-15) (R-16) (R-17) (R-18) (R-19) F3 (R-20) (J?-21) CR3 (R-22) (R-23) The reducing agent represented by the above general formula (1) can be prepared by a known method,
For example, Huiben Peil, Methoden der Organizi in Hemi, Band XI/2 ()-1oube
n-Weyl, Methoden der Qrg
anischen Chemie, 13and
XI/2) 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-aminophenol, etc.), sulfonamidophenols [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-carboxycatechol, etc.), naphthols (e.g. α-naphthol, β-naphthol, 4-aminonaphthol, 4-methoxynaphthol, etc.) ), hydroxybinaphthyls and methylene bisnaphthols [e.g. 1,1'-dihydroxy-2,2'
-binaphthyl, 6,6'-dibromo-2,2'-dihydroxy-1,1'-binaphthyl, 6,6-sinitro2
．． 2'-dihydroxy-1,1'-binaphthyl, 4.4
1-dimethoxy-1,1'-dihydroxy-2,2'-
binaphthyl, bis(2-hydroxy-1-naphthyl)methane, etc.], methylenedosphenols [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-t
ert-butylphenyl)methane, α-phenyl-α,
α-bis(2-hydroxy-3-tert-butyl-5
-methylphenyl)methane, 1.1-bis(2-hydroxy-3,5-dimethylphenyl)-2-methylpropane, 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-
Methyl-5-tert-bubulphenyl)propane,
2.2-bis(4-hydroxy-3,5-tert)
- butylphenyl) propane, etc. J1 ascorbic acids,
Examples include 3-pyrazolidones, pyrazolones, hydrazones 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 organic acid silver salt, and the type of other additives, but it is usually 0 per mole of photosensitive silver halide. in the range of .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 binders such as polyvinyl butyral, polyvinyl acetate, ethyl cellulose, polymethyl methacrylate, cellulose acetate butyrate, polyvinyl alcohol, polyvinyl pyrrolidone, gelatin, and phthalated gelatin. One or a combination of two or more polymeric substances can be used. In particular, it is preferable to use gelatin or a derivative thereof in combination with a hydrophilic polymer such as polyvinylpyrrolidone or polyvinyl alcohol, and more preferably a binder such as the one described in JP-A-122-1999 TTG 4i.

This binder includes gelatin and vinyl and lolidone polymers. The vinyl pyrrolidone polymer may be polyvinyl pyrrolidone, which is a homopolymer of vinyl pyrrolidone, or a copolymer (including a graft copolymer) of vinyl pyrrolidone and one or more other monomers copolymerizable with vinyl pyrrolidone. ). These polymers can be used regardless of their degree of polymerization. polyvinyl a
The lydone may be substituted polyvinylpyrrolidone, with preferred polyvinylpyrrolidone having a molecular weight of 1,000 to 4.
00,000. Other monomers copolymerizable with vinylpyrrolidone include (meth)acrylic acid esters such as acrylic acid, methacrylic acid and alkyl esters thereof, vinyl alcohols, vinyl imidazoles, (meth)acrylamides, and vinyl carbinols. and vinyl monomers such as vinyl alkyl ethers, but it is preferable that polyvinylpyrrolidone accounts for at least 20% of the composition ratio (weight R%, hereinafter the same). A preferred example of such a copolymer has a molecular weight of 5.00.
0 to 400.000.

Gelatin may be treated with lime or acid, and may be ossein gelatin, big skin gelatin, hydrogelatin, or modified gelatin obtained by esterifying or finylcarbamoylating these gelatins.

In the above binder, gelatin preferably accounts for 10 to 90% of the total binder amount, more preferably 20 to 60%, and vinylbiolidone 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 a mixture of polyvinylpyrrolidone with molecules 11.0 < 10 to 400,000 and one or more other polymeric substances, gelatin and molecules 15,000 to 400.0
A mixture of the vinylpyrrolidone copolymer No. 00 and one or more other polymeric substances is preferred. Other polymeric substances that can be used include polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyvinyl butyral, polyene glycol, polyethylene glycol ester, proteins such as cellulose derivatives, and polysaccharides such as starch and gum arabic. Examples include natural substances. These are 0-85%, preferably 0-70%
May be included.

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 a support (including the case where the crosslinking reaction progresses by leaving it to stand).

The binder usage is usually 112 o to 112 o per layer.
, osg to 50g, preferably 0.1g to 10(
].

The support used in the heat-developable photosensitive material of the present invention includes:
For example, polyethylene film, cellulose acetate film and polyethylene terephthalate film, synthetic plastic films such as polyvinyl chloride, and 9
Examples include paper supports such as paper base paper, printing paper, baryta paper and resin-coated paper, and supports prepared by providing the above-mentioned synthetic plastic film 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. Pat.
No. 40, No. 3,531,285, No. 4.012,
No. 260, No. 4,060,420, No. 4,088
, No. 496, No. 4.207.392, specifications, RD
No. 15733, No. 15734, N.
o, 15776, alkali release agents such as urea and guanidium trichloroacetate described in JP-A-56-130745 and JP-A-56-132332, etc.;
Organic acids described in US Pat. No. 5-12700, US Pat. No. 3,667
．． Non-aqueous polar solvent compound having 100+, -302-, -3o- groups described in No. 959, Beienji edition No. 3,438
, 776, US Pat. No. 3,6
66.477, and polyalkylene glycols described in JP-A-51-19525. In addition, as a color toning agent, for example, JP-A No. 46-4928, JP-A No. 46-6077
No. 49-5019, No. 49-5020, No. 4
No. 9-91215, 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
5 (No. 114, No. 54-156523, No. 54-1)
No. 56524, No. 54-156525, No. 54-
No. 156526, No. 55-4060, No. 55-406
Publications such as No. 1 and No. 55-32015, as well as West German Patent No. 2.140.406 and West German Patent No. 2,147,063,
No. 2.220,618, U.S. Patent No. 3.080.2
No. 54, No. 3,847,612, No. 3,782,
No. 941, No. 3.994.732, No. 4,123
Phthalazinone, phthalimide, pyrazolone, quinazolinone, N-hydroxynaphthalimide, benzoxazine, naphthoxazinedione, 2,3- Dihydro-phthalazinedione, 2,3-dihydro-1,3-oxazine-2,4-dione, oxypyridine, aminopyridine, hydroxyquinoline, aminoquinoline, isocarbostyryl 2H-1,3-benzothiazine-2.4 - (3H)dione, benzo-1-heriazine, mercapto-1-riazonyl, dimercabutotetrazapentalene, phthalic acid, naphthalic acid, phthalamic acid, etc., and one of these or
mixtures of phthalazine and at least one acid or acid anhydride such as phthalic acid, naphthalic acid, or an acid anhydride and a phthalazine compound; Examples include combinations. Also, JP-A-5
3-amino-5-mercapto-1,2,4- described in No. 8-189628 and No. 58-193460
Triazoles, 3-acylamino-5-mercapto-
1,2,4-triazoles 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. 50-1
No. 23331, No. 51-47419, No. 51-574
No. 35, No. 51-78227, No. 51-10433
No. 8, No. 53-19825, No. 53-20923,
51-50725@, 51-3223, 51-
42529@, Shu 51-81124, Shu 54-518
Publications such as No. 21 and No. 55-93149, as well as British Patent No. 1.455,271, U.S. Patent No. 3,885,
No. 968, No. 3, No. 700.457, No. 4,137
, No. 079, No. 4,138.265, West German Patent No. 2
, 617,907, etc., or oxidizing agents (e.g., N-halogenoacetamide, N-halogenosuccinimide, perchloric acid and its salts, inorganic peroxide). 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, thiouracil, Examples include disulfide, simple sulfur, mercapto-1,2,4-triazole, thiazolinthion, polysulfide compounds, etc.), and other compounds such as oxazoline, 1.2°4-triazole, and phthalimide. Furthermore, thiol (preferably a thiophenol compound) compound described in JP-A-59-111636 is also effective as another antifoggant.

In addition, as other antifoggants, Japanese Patent Application No. 59-565
Hydroquinone derivatives described in No. 06 (e.g., di-t
-octylhydroquinone, dodecanylhydroquinone, etc.) or hydroquinone derivatives described in Japanese Patent Application No. 59-66380, and benzotriazole derivatives (e.g., 4-sulfobenzotriazole, 5-carboxybenzotriazole, etc.) are preferably used in combination. can.

In addition, as a stabilizer, a print-out preventive agent may be used at the same time, especially after processing. Halogenated hydrocarbons, specifically tetrabromobutane, tribromoethanol, 2-bromo-2-tolylacetamide, 2-
Examples include bromo-2-tolylsulfonylacetamide, 2-tribromomethylsulfonylbenzothiazole, and 2,4-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;
506, 444, same No. 3.824.103, same 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 breaker etc. described in 060,420 and the like.

In addition, sucrose, NH4Fe (S04)2・12H20
Water release agents such as
Heat development may be carried out by supplying water as in No. 132332.

In addition to the above-mentioned components, the heat-developable photosensitive material of the present invention may further contain various additives such as antihalation dyes, optical brighteners, hardeners, antistatic agents, plasticizers, and spreading agents, as well as coating aids. Agents etc. can be added.

When the heat-developable light-sensitive material of the present invention is a color type, the dye-providing material is more effective.

Dye-providing substances that can be used in the present invention will be explained below. The dye-donating substance may be any substance that participates in the reduction reaction of the photosensitive silver halide and/or the optionally used silver salt and can form or release a diffusible dye as a function of the reaction. , depending on their reaction form, a negative dye-donor that acts on a positive function (i.e., forms a negative dye image when negative-working silver halide is used) and a positive dye donor that acts on a negative function. dye-donor materials (that is, those that form a positive dye image when negative-working silver halide is used). 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 reducing dye-releasing compounds include JP-A-57-179840, JP-A-58-116537, and JP-A No. 58-116537.
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 mentioned.

In the margin below, exemplified dye-donor substances 0C16S (.) OC76Hss (n) CrH5, Ctonocr4. Mix (negative) Another reducing dye releasing compound is, for example, the general formula (3)
Examples include compounds represented by:

General formula (3) In the formula, A1 and A2 each represent a hydrogen atom, a human oxy group, or an amino group, and Dye is a Dye represented by the general formula (2).
is synonymous with Specific examples of the above compounds are given in JP-A-59-12
No. 4329.

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

General formula (4) % formula % In the formula, Cpl is a val (so-called coupler residue) that can react with the oxidized form of the reducing agent to release a diffusible dye, and J is a divalent bonding group. The bond between Cp+ and J is cleaved by the reaction of the reducing agent with the oxidized product. nl
represents 0 or 1, and Dye has the same meaning as defined in general formula (2). Further, C11+ 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). or a hydrophilic group such as a sulfo group or a carboxy group, or a group having both 8 or more (more preferably 12 or more) carbon atoms and a hydrophilic group such as a sulfo group or a carboxy group. 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 four specifications of Japanese Patent Application No. 59-104901, and include, for example, the following compounds.

Exemplary dye-providing substance ■ 0CR1 ■ 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 C112 preferably has a molecular weight of 700 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 monomer represented by general formula (6).

General formula (6) % formula %)) In the formula, C1)2 and F have the same meanings as defined in general formula (5), Y represents an alkylene group, arylene group or aralkylene group, and 2 is O or 1, Z is 2
represents a valent organic group, and 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-59-1243
No. 39, No. 59-181345, patent application No. 58-109
No. 293, No. 59-179657, No. 59-18
No. 1604, No. 59-182506, No. 59-18
It is described in various Mei IB books such as No. 2507, and examples thereof include the following compounds.

0CHC, 4H,.

OOH ■ C, AH,.

■ Polymer 0H x: 60 weight% y: 40 weight% @ CH3 , (5) and (6), CI
)+ or CD2, a group represented by the following general formula is preferred.

General formula (7) General formula (8) General formula (9
) General formula Cto) General formula (/3)
General formula (I+) General formula (/S′″)
General formula (16) below f, e In the formula, R7, R1? ,R? and RIo are 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, a carbamoyl group, a sulfamoyl group, an acyloxy group, amiLL alkoxy group,
It represents an aryloxy group, a cyano group, a ureido group, an alkylthio group, an arylthio group, a carboxy group, a sulfo group, or a heterocyclic residue, which can further be a hydroxyl group, a carboxy group, a sulfo group, an alkoxy group, a cyano group, a nitro group, or an alkyl group. group, aryl group, aryloxy group, acyloxy group, acyl group, sulfamoyl group, carbamoyl group,
It may be substituted with an imide group, a halogen atom, etc.

These substituents are selected depending on the purpose of CD1 and CI)2, and as mentioned above, in <C111, one of the @ substituents is preferably a ballast group, and in C1)2, it is preferable that one of the @ substituents is a ballast group. The molecule ω is 100 to increase diffusivity.
Hereinafter, the number of substituents is preferably selected to be 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).

General formula (17) In the formula, Wl represents a collection of atoms necessary to form a quinone ring (which may have a substituent on this ring),
Rtl represents an alkyl group or a hydrogen atom, R'3 represents an oxygen atom, O or 1, and Dye has the same meaning as defined in general formula (2).This compound Specific examples are described in the specifications of JP-A-59-166954 and JP-A-59-154445, and include the following compounds.

Exemplary dye-donor substance OSOz H3 ■ CH3 Another positive dye-donor substance is the following General 1 (18)
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), and R''
, r, E, and Dye have the same meanings as defined in general formula (17). A specific example of this compound is JP-A No. 5
It is described in specifications such as No. 9-124329 and No. 59-154445, and includes, for example, the following compounds.

Examples of dye-donating substances
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.

Exemplary dye-donor substances of general formula (2), (3), (4), (17) (18)
) and (19), the residue of the diffusible dye represented by Dye will be explained in further detail. The residue of the diffusible dye has a molecular weight of 800 or less, more preferably 6001 or less for the sake of dye diffusivity. These dye residues include residues of dyes, quinoline dyes, carbonyl dyes, phthalocyanine dyes, etc.These dye residues may be in a temporary short-waveform form that is capable of multicoloring during heat development or transfer. For the purpose of increasing the light resistance of images, for example, Japanese Patent Laid-Open No. 5
Chelatable dye residues described in No. 9-48765 and No. 59-124337 are also preferred.

These dye-providing substances may be used alone or in combination of two or more. The amount used is not limited, and it 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 heavy layer of two or more layers. The amount may be determined depending on the situation, but for example, the amount used can be from 112 o.oosg to 50 g, preferably from 0.1 g to 10 g.

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 acid (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 obtained by imagewise exposure to radiant radiation, including visible light. Generally, light sources used for ordinary color printing, such as tungsten lamps, mercury lamps, xenon lamps, laser beams, CRT beams, etc., can be used as the light source.

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, high frequency heating may be used, or furthermore, a conductive layer may be provided in the photosensitive material of the present invention or in the image receiving portion for thermal transfer, and Joule heat generated by electricity or a strong magnetic field may be utilized. There are no particular restrictions on the heating pattern, including methods of 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 heated at 80°C after image scratching exposure.
1 second to 240 seconds, preferably 1.5 seconds to 12 seconds at a temperature range of ~250°C, preferably 100°C to 200°C.
Developed by heating for 0 seconds. Also, before exposure,
Preheating may be performed in a temperature range of 0°C to 200°C.

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, No. 51-80226, etc.) can be used, but Japanese Patent Application Laid-open No. 59-136733, Research Disclosure No. 0.16407, No. 0.1640
A bleach-fixing sheet such as that described in No. 8, No. 16414 may also be used.

In addition, when the heat-developable light-sensitive material, which is a preferred embodiment of the present invention, is a color type that uses a dye-providing substance, the image-receiving member and the exposure layer side of the photothermographic layer of the present invention, which will be described later, are in a stacked relationship. at a temperature range of usually 80°C to 200°C, preferably 120°C to 170°C, for 1 second to 1 second.
By heating for 80 seconds, preferably from 1.5 seconds to 120 seconds, the image is transferred to the image receiving member simultaneously with color development.

Moreover, you may perform preheating in the temperature range of 70 degreeC - 180 degreeC before exposure.

The passive member used in the present invention may 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 organic polymer material having a glass transition temperature of 40° C. or higher and 250° C. or lower as described in Japanese Patent No. 07250 or the like.

Specific examples of the mordants include nitrogen-containing secondary and tertiary amines, nitrogen-containing heterocyclic compounds, quaternary cationic compounds thereof, U.S. Pat. No. 2,548,564, U.S. Pat.
4.430, 3,148,061, 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 derivatives, JP-A-1987
Covalently reactive polymers described in U.S. Pat. No. 3,625,694 and U.S. Pat.
96, British Patent No. 1,277.453, British Patent No. 2,01
No. 1,012, a mordant capable of crosslinking with gelatin, etc.; U.S. Pat. No. 3,958,995;
21,852 and 2,798.063, a water-insoluble mordant disclosed in JP-A-50-61228, and US G11lrf13.7.
No. 88,855, West German patent ratio 1m (OLS) No. 2,84
No. 3,320, JP-A No. 53-30328, JP-A No. 52-1
No. 55528, No. 53-125, No. 53-1024
No. 54-74430, No. 54-124726,
No. 55-22766, 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. 5B-36414,
Various mordants disclosed in No. 57-12139 and 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 a support made of a polymer containing ammonium salts mixed with gelatin.

Obtained by coating on top.

Examples of the heat-resistant polymeric substance include molecules l 2,
000 to 85,000 polystyrene, polystyrene derivatives with substituents having 4 or less carbon atoms, polyvinylcyclohexane, polyallylbenzene, polyvinylpyrrolidone,
Polyacetals such as polyvinyl carbazole, polyallylbenzene, polyvinyl alcohol, polyvinyl formal and polyvinyl butyral, polyvinyl chloride,
Chlorinated polyethylene, polytrichlorofluoroethylene, polyacrylic nitrile, poly N, N-dimethylacrylamide, polyacrylate with p-cyanophenyl group, pentachlorophenyl group and 2,4-dichlorophenyl group, polyacryl chloroacrylate, poly Methyl methacrylate, polyethyl methacrylate, boria 0 methyl 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, the Polymer Handbook 2nd Edition (polymer@andboo
K 2nd ed.), edited by G. Brandrup and E.H. Inmargt (J, 3ra
John Wiley & Sons Publishing (John W.
Also useful are synthetic polymers with glass transition temperatures of 40°C or higher, such as those described in 1ley & 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-local boxyphenoxybutane 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. Particularly preferred among these are the layer made of polyvinyl chloride described in Japanese Patent Application No. 58-97907, and the layer made of polycarbonate and a plasticizer described in Japanese Patent Application No. 128600-1982.

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.

In the following margin [Specific Examples of the Invention] The present invention will be specifically described below with reference to Examples, but the embodiments of the present invention are not limited to these.

Example 1 [Preparation of silver bromide emulsion] Comparative silver bromide emulsion A was prepared by the following method. Using the mixer shown in the specifications of JP-A-57-92523 and JP-A-57-92524, 20 g of ossein gelatin, 1000 μl of distilled water, and ammonia were dissolved in solution (A) at 50° C., and bromide was added to the solution (A). 500 mQ of solution (B), an aqueous solution containing 1.1 mol of potassium, and 500 mQ of solution (C), an aqueous solution containing 1 mol of silver nitrate and ammonia, were simultaneously added while keeping DA (+ constant). [The shape and size of the emulsion grains at pH 11) A(l and (B
The silver halide grains obtained were octahedral grains with an average grain size of 0.3 μm and a monodispersity of 8%.

This emulsion was washed with water and subjected to dehydration. The amount of emulsion is aoot
It was c.

[Preparation of silver iodobromide emulsion] Next, potassium iodide and potassium bromide were added to solution (A) in which 20 g of ossein gelatin, 1000147 distilled water, and ammonia were dissolved at 50° C. using the above-mentioned mixing stirrer. For emulsion B, the aqueous solution containing potassium iodide 6.64G
, potassium bromide 130.9 (1, for emulsion C potassium iodide 11.62 !It , potassium bromide 130.9!
It (B) solution 500iN and (C) solution consisting of an aqueous solution containing 1 mol of silver nitrate and ammonia 500iN
Q was added at the same time while keeping the pAg constant. The shape and particle size of the emulsion grains to be prepared are as follows: pH 11) A(] and (B)
It was adjusted by controlling the addition rate of the liquid and the liquid (C). In this way, comparative emulsions B and C, which had the same regular octahedral shape but differed only in silver iodide content, were prepared. (The monodispersity of each emulsion was 9%.) Each of these emulsions was washed with water and desalted. The loss for each emulsion B and C is 800.
It was d.

[Preparation of core/shell type silver iodobromide emulsions] Core/shell type emulsions of the present invention having different iodides, silver contents and grain sizes, E,
F was adjusted by the following method.

Ossein gelatin 2 at 50°C using the above mixing stirrer.
0g, distilled water 1000112 and ammonia in solution (A), and for emulsion, potassium iodide 11
, 62G, potassium bromide 130.9 (+, potassium iodide 11.62 (J, potassium bromide 1
30.9g, potassium iodide for emulsion E 24.91)
, 500 t12 of solution (B), an aqueous solution containing 119.0 (l) of potassium bromide, and solution (C), soo, Q, an aqueous solution containing 1 mol of silver nitrate and ammonia, were simultaneously DA
It was added while keeping Q constant. The particle shape and particle size of the core emulsion to be prepared are I) H, pAa, (B) liquid and (C)
Adjustments were made by controlling the rate of liquid addition.

In this way, core emulsions having the same regular octahedral shape, different grain sizes, and different silver iodide contents were prepared. The monodispersity of each emulsion was 8%.

By coating the core silver halide grains with a shell in the same manner as above, a core/shell type emulsion D-F with the same regular octahedral shape, different average grain size, and different silver iodide content was created. was prepared.

Each of these emulsions was washed with water and desalted to give 900w12.

The above emulsions A, B, C, D, E, and F are summarized in Table 1 below.

Table 1 The following photocombination [Preparation of organic silver salt dispersion-1] 5-methylbenzotriazole silver 28.8a obtained by reacting 5-methylbenzotriazole and silver nitrate in a water-alcohol mixed solvent and poly(N -vinylpyrrolidone) and 4-sulfobenzotriazole sodium salt 1,33a were dispersed in an alumina ball mill to make pt-15,5, and a modified silver salt dispersion of 200 g was prepared by WA.
Manufactured.

[Preparation of photosensitive silver halide dispersion-1] Silver halide emulsions A, B, C1D, E, and F prepared above were mixed with the following sensitizing dye (1) and 4-hydroxy-6-methyl-1,3
, 3a, 7-chitrazaindene was subjected to sulfur sensitization treatment with sodium thiosulfate to prepare a photosensitive silver halide dispersion-1 having the following composition.

Silver halide (in terms of silver) 3811;1
Gelatin asg /2820d[
Dye-donor dispersion liquid-1 manufactured by WA] Exemplary dye-donor substance (Q) 35.5111 and 7.5 mmol each of the compounds shown in Table 2 were added to 20 ml of ethyl acetate.
0m (dissolved in 2, Alkanol XC (manufactured by DuPont)
Type 5 warm % aqueous solution 124 years old, phenylcarbamoylated gelatin (Rouslow, Type 17819p C) 30,5
After mixing with 720 g of gelatin aqueous solution containing 0 and decomposing with an ultrasonic homogenizer and distilling off ethyl acetate,
5.5 and 795 was used to prepare a dye-providing substance dispersion-1.

At this time, the drooxybenzene derivative of the present invention <l-5)
was dissolved in hot water and added.

[Preparation of reducing agent dispersion-1] Exemplary reducing agent (R-11>23.30, (development accelerator 1.109 below), poly(N-vinylpyrrolidone) 14
．． 60, 0.501 l of the following fluorine-based surfactant was dissolved in water and adjusted to DI-15.5 to 250 i to prepare reducing agent dispersion-1.

Margin below: Development accelerator CH2CH=CH2 Surfactant [Preparation of heat-developable photosensitive material-1] Organic silver salt dispersion 12.5d prepared above, silver halide dispersion 6.00mR1 Dye-donor dispersion-1 39.8d of Reducing Agent Dispersion-1, 12.5 of Reducing Agent Dispersion-1. J7, and further, a hardening agent solvent (tetra(vinylsulfonylmethyl)methane) and taurine were reacted at a ratio of 1:1 (ffiffi ratio), and the mixture was dissolved in a 1% aqueous solution of phenylcarbamoylated geladine to form tetra(vinylsulfonylmethyl). Methyl) methane is made to have triple side%.) is 2.501Q,
After adding 3.80 (l) of polyethylene glycol 300 (Kanto Kagaku) as a heat solvent, the thickness was subtracted.
Silver m was coated on a 180 μm photographic polyethylene terephthalate film at a ratio of 1.76 (1/V).
Furthermore, a protective layer made of a mixture of the phenylcarbamoylated gelatin and poly(N-vinylpyrrolidone) was provided thereon.

Sample Nos. 1 to 15 of photothermographic materials shown in Table 2 below were prepared.

[Preparation of image receiving member-1 J] Polyvinyl chloride (n=1.10
Apply a tetrahydrofuran solution of 0.0, Wako Tsumugi Pharmaceutical),
Image receiving member-1 was prepared in which polyvinyl chloride had a ratio of 12 Q/f.

The photothermographic material was exposed to 1,600C, M, and S through a step wedge, and was then exposed to light at 1,600C, M, and S using a heat development machine (developer module: L-/L/
After heat development at 7150°C for 1 minute, the photothermographic material and the image-receiving member are quickly peeled off, and a magenta step wedge negative is left on the polyvinyl chloride surface of the image-receiving member. The image was obtained.

The green reflection density of the obtained negative image was measured using a densitometer (PDA-65
(manufactured by Konishiroku Photo Industry ■).

Minimum density (fog) maximum density and relative sensitivity are shown in Table 2 below.
Shown below.

Table 2) X7 Note that the relative sensitivity here is the reciprocal of the exposure that gives a density of fog + 0.3, and is expressed as a relative value with the value of sample (1) as 100.

Furthermore, the following compound <a) was used as a comparative compound for the present invention.

From the results in Table 2, for comparison photosensitive materials Nos. 1 to 5,
When silver halide emulsions D1E and F with high silver iodide content are used, the sensitivity increases, but the minimum density (
Fog) becomes high, and the emulsions of the present invention, E, F
and sample N using the hydroxybenzene derivative of the present invention.
o, 8-10: No.

It was confirmed that samples Nos. 12 to 15 not only had high sensitivity but also had low minimum density (fogging) and had excellent characteristics. In addition, Sample No. 11, which uses a compound (a) which is known to be included in a heat-developable photosensitive layer as an auxiliary compound and which is chemically similar to the compound of the present invention, increases fogging. .

In addition, sample No. using emulsions A and B outside the scope of the present invention
, 6.7, the relative sensitivity is insufficient.

Example 2 [Preparation of photosensitive silver halide dispersion-2] The silver halide prepared in Example-1 was mixed with the following sensitizing dye and 4-hydroxy-6-methyl-1,3°3a,7-titrazaindene. A photosensitive silver halide emulsion dispersion having the following composition was prepared by sulfur sensitization treatment with sodium thiois in the presence of sulfur.

Sensitizing dye (2) Silver halide (in terms of silver) 3811) Gelatin 85 (1/28201Q [
Preparation of dye-providing substance dispersion-2] Exemplary dye-providing substance (■) 30.01; l, and Table -
30 mmol of tricresyl phosphate, respectively. OQ and ethyl acetate were dissolved in 90.0ml of ethyl acetate, mixed with 460d of gelatin aqueous solution containing a surfactant, same as in Example-1, dispersed with an ultrasonic homogenizer, ethyl acetate was distilled off, water was added, and soo. , f
A dye-providing substance dispersion-2 was prepared.

Here, the hydroxybenzene of the present invention shown in Table 3 (
Only I-5) was dissolved in hot water and added.

[Preparation of heat-developable photosensitive material-2] 40. Photosensitive silver halide emulsion dispersion-2. (hffi
, 25. of Organic Silver Salt Dispersion-1. OnQ, dye donor dispersion liquid-2 so and oll were mixed, and polyethylene glycol 300 (Kanto Kagaku) was added as a heat solvent. 4.2
0Q, same as Example-1 ii! Membrane agent 3.00- and 10% by weight water-alcoholic solution of guanidine trichloroacetic acid 20. Thickness after adding OnQ and underlining 180
A silver plate of 2. The samples were coated so as to give soo/v, and samples Nos. 16 to 30, shown in Table 3 below, with zero thermal development sensitivity were prepared.

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

(1) Layer made of polyacrylic acid. (7,009/l'
) (2) A cell consisting of cellulose acetate. (4,0Og/
f) (3) A layer consisting of a 1=1 copolymer of styrene and N-benzyl-N, N-dimethyl-N-(3-maleimidopropyl) ammonium chloride and gelatin.
(Copolymer 3.00 (1/1"> (gelatin 3.0 oil/m')) The photothermographic material-2 was exposed to 1,600 C, M, S through a step wedge, and After heating for 1 minute on a heat block, it was bonded to the image receiving member-2 immersed in water, and heated at 50° C. and 500° C.
00C1/cv was crimped for 30 seconds and then peeled off in an easy manner. The transmission density of the yellow transparent image obtained on the surface of the image receiving member was measured using a densitometer (PDA-65, Konishiroku Photo Industry (!
1) Measured at W>. For sample Nos. 16 to 30, the minimum concentration, maximum 1 degree, and relative sensitivity are shown in Table 3 below.

Table 3: Relative sensitivity is the reciprocal of the exposure depth that gives a density of fog + 0.3, and is expressed as a relative value with the value of sample (16) as 100.

Further, the following compound (b) was used as a comparative compound for the present invention.

As is clear from Table 3, similar to the results of Example 1, a comparison was made with the heat-developable photosensitive material using a dye-providing substance that reacts with photosensitive silver halide to release an aqueous dye when heated. Sample No.

In Nos. 16 to 20, when the silver halide emulsion DSE, F with a high silver iodide content is used, although the sensitivity becomes high, the minimum toughness becomes high due to heat development. Tests 1mNo. 21 to 29 using F and the hydroxybenzene derivative of the present invention not only had high sensitivity but also
The minimum concentration was lowered and the maximum concentration was maintained, confirming excellent properties. In addition, sample No. 30 using comparative compound (b) increased fogging.

In addition, sample No. 2 using emulsion C outside the scope of the present invention
At 0, the relative sensitivity is insufficient. It was found that in the samples using the silver halide grains of the present invention and the hydroxybenzene derivative of the present invention, the antifogging effect was exhibited without significantly lowering the maximum density, and it was found that the samples had high sensitivity.

Patent applicant Konishiroku Photo Industry Co., Ltd. Procedural amendment m<self-interest December 5, 1986 Commissioner of the Patent Office Black 1) Akio-dono (].

1. Indication of the case 1985 Patent Application No. 232650 2. Name of the invention Photothermographic material 3. Person making the amendment Relationship to the case Patent applicant address 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(127) Representative Director of Konishiroku Photo Industry Co., Ltd.
One Hand, Inchu 4, Agent 102 Address: Kudan-Rosaka Pill, 4-1-1 Kudankita, Chiyoda-ku, Tokyo Tel: 263-9524 Mei III's [3. Detailed Description of the Invention] Column 6, Amendment The detailed description of the invention for Contents m is amended as follows.

(1) The statement "...Silver salt of sulfobenzotriazole derivative..." on page 52, lines 3-4 of the specification box has been changed to "...
Silver salt of sulfobenzotriazole derivative or methylbenzotriazole derivative...'' is corrected.

(2) Amend Table 2 on page 116 of Mei 1 as shown in the attached sheet.

that's all (Separate edition) Table-2

Claims (1)

[Scope of Claims] At least one of the silver halide emulsion layers on the support includes core/shell type photosensitive silver halide grains having a silver iodide content of 4 to 40 mol %, and a compound having the following general formula: 1. A photothermographic material characterized by containing at least one compound selected from a compound represented by [I] and a compound represented by the following general formula [II]. General formula [I] ▲There are numerical formulas, chemical formulas, tables, etc.▼ In the formula, R_1 is a halogen atom, an alkyl group, an aryl group, an acyl group, an alkyloxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, Alkylamino group, arylamino group, carbamoyl group, acylamino group, alkoxy group, sulfamoyl group, alkylsulfonylamino group, arylsulfonylamino group, sulfonic acid group or its salt, carboxylic acid group or its salt, nitro group or hydroxyl group. represent. R_2 and R_3 represent a hydrogen atom or a protecting group that is decomposed and removed. n represents an integer from 1 to 4. General formula [II] ▲There are numerical formulas, chemical formulas, tables, etc.▼ In the formula, R_4 represents a hydrogen atom, an alkyl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkylaminosulfonyl group, or an arylaminosulfonyl group, and R_5 represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkoxy group, an acylamino group, or a sulfamoyl group, and X represents (R_5)_2 or an atomic group necessary to form a carbon ring. However, if X is (R
_5) In the case of _2, R_5 may be the same or different. R_6 represents a hydrogen atom or a protective group that decomposes and leaves, R_7 represents a group with a total number of carbon atoms of 7 or more, and m is 0.
An integer of ~2, m_1 represents 0 or 1.