JPS6289037A - Heat developable photosensitive material - Google Patents

Abstract

PURPOSE:To decrease the deterioration of sensitivity by heat development by using photosensitive silver halide particle which contains silver iodide in a specific range and has a certain grain size distribution in combination with two kinds of specific sensitizing dyes. CONSTITUTION:The photosensitive silver halide particle which contained 4-40% silver iodide and has <=0.4mum average grain size and two kinds of the specific sensitizing dyes are combined and are used in at least one layer of silver halide emulsion layers. More specifically, the plural compds. which are formed of an alkyl group, halogen atom, alkoxy group, amino acid, acylamide group, acyloxy group, alkoxycarbonyl group, etc., and are expressed by the general formula are used as the sensitizing dyes. A org. silver salt dispersion, silver halide dispersion, color donative dispersion, and reducing agent dispersion are prepd. and mixed and a film hardener soln., etc., are added to the mixture. Such mixture is coated on a polyethylene terephthalate film for photography and a protective layer is provided thereon. The deterioration of the sensitivity by the heat development is thereby decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a thermal phenomenon photosensitive material having improved heat development sensitivity in heat development.

BACKGROUND OF THE INVENTION] The method of performing the current step (2) for obtaining the image (2) by dry heat treatment has many advantages over the conventional wet method 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.
No. 3-4924 discloses a black-and-white photothermographic material comprising a silver salt, a silver halide, and a 7-base 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. 57-1867
No. 44, No. 57-198458, No. 57-2072
No. 50, No. 58-40551, No. 58-58543, No. 58-79247, No. 59-12431, No. 59-22049, No. 59-68730, No. 59
-124339, 59-124333, 59-
No. 124331, No. 59-159159, No. 59-1
No. 81345, No. 59-159161, No. 58-11
No. 6537, No. 58-123533, No. 58-1
There are No. 49046 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. , a binder. In the present invention, only the photosensitive element is referred to as a heat-developable photosensitive material.

In Ichibuki's black and white type, optical information is given to the photosensitive silver halide by one exposure point, and in heat development,
The photosensitive silver halide in the photosensitive layer and the reducing agent cause an oxidation-reduction reaction due to the catalytic action of the exposed photosensitive silver halide present in the vicinity, producing a limit, and the exposed portion of the photosensitive layer becomes black. A silver image is formed.

In addition, in the color type, optical information is given to the photosensitive silver halide by image exposure, and in heat development,
In 5 and 5 of the action of the reducing agent, dissolution physical development is performed between the silver salt and the photosensitive silver halide according to optical information, and the reducing agent that has acted or has not acted becomes the dye-donating substance. A dye that forms an image is released or formed by reaction. The image Q-forming dye obtained by thermal development is transferred to an image receiving element to form an image.

In both the black-and-white type photothermographic material Fl and the color type photothermographic material Fl by forming the above-mentioned image, an image is usually formed by thermal development after exposure or simultaneously with exposure. Generally, thermal phenomena are carried out at high temperatures of 80° C. or higher, and therefore have a considerable influence on silver halide. One of the biggest effects is desensitization due to thermal development. That is, for comparison, an exposed heat-developable photosensitive material was treated with a generally widely used wet photographic processing solution.
80°C or less for the sensitivity during development processing.
It has become clear that the sensitivity is low when thermally developed at temperatures above ℃.

Furthermore, in heat-developable photosensitive materials containing sensitizing dyes,
There was a disadvantage that desensitization due to this thermal phenomenon did not show a significant tendency.

This phenomenon is thought to be due to a part of the latent image formed on the silver halide of the exposed photothermographic material being thermally bleached during thermal development, but this is not clear.

Additionally, adding a sensitizing dye to silver halide gives silver halide high photosensitivity to visible light to infrared light through spectral sensitization, which is also essential for heat-developable light-sensitive materials. Therefore, there is a particular need for improvement in the sincerity produced by such heat development.

Regarding the above problem, as a result of extensive and practical research, the present inventors have determined that photosensitive silver halide grains containing silver iodide in a specific range and having a particle size distribution consisting of two specific types of sensitizing dyes are combined. It was discovered that the decrease in sensitivity due to thermal phenomena is reduced in the heat-developable photosensitive materials used in the photothermographic materials, and the present invention was accomplished.

[Object of the Invention] Accordingly, an object of the present invention is to provide a heat-developable photosensitive material that exhibits little decrease in sensitivity due to rapid heat development.

[Structure of the Invention] The above-mentioned object of the present invention is to provide at least one silver halide emulsion layer of a heat-developable photosensitive material containing 4 to 40 mol% of silver iodide aggregate graphite and having an average grain size of 0.4 μm. This can be achieved using the following photosensitive silver halide grains and a photothermographic material containing a combination of at least one compound represented by the following general formula (I) and at least one compound represented by the following general formula (I[). Ta.

General formula (I) [wherein Yl, Y2, Y3 and Y4 are each a hydrogen atom, a halogen atom, a hydroxyl group, an alkoxy group, an amine group, an acylamido group, an acyloxy group, an alkoxycarbonylcarbonylamino group, an aryl group, a cyanobase , represents an alkyl group or a carboxyl group, and either Yl, Y2 or Y3 and Y4 may be connected to form a ring to form a naphthoxazole ring. Further, R1 represents a hydrogen atom or an alkyl group, R2 and R3 each represent an alkyl group, x1 represents an anion, and m
represents an integer of 1 or 2. However, when m represents 1, R2 yo or R3 represents a base capable of forming an inner salt] General formula (I[) [wherein Y5, Y6, Yl and Y8 are each hydrogen represents an atom, a halogen atom, a hydroxyl group, an alkoxy group, an amino group, an acylamido group, an acyloxy group, an alkoxycarbonyl group, an alkoxycarbonylaminolkyl group, or a carboxyl group, and Y5 and Y6 and/or Yl and Y8 are each connected to form a ring. may be formed to form a naphthodiazole ring. Further, R4 represents a hydrogen atom or an alkyl group, R5 and R6 each represent an alkyl group, x20 represents an anion, and n represents an integer of 1 or 2. However, n is 1
When R5 or R6 represents a group capable of forming an inner salt. ] [Specific structure of the invention] The compounds represented by the general formula (I) and the general formula (II) (hereinafter referred to as the compounds of the invention) used in the invention are sensitizing dyes.

In the general formulas (I) and (II), the alkyl groups represented by R1 and R4, respectively, are preferably lower alkyl groups, such as methyl, ethyl, and propyl groups. Examples of the alkyl groups represented by R2 and R3 and R5 and R6 include a methyl group, an ethyl group, a sulfoethyl group, a callevoxypropyl group, a butyl group, and a sulfobutyl group.

Next, in the general formula, Yl, Y2, Y3 and Y4
The halogen atoms represented by Y5, Y6, Yl and Y8 include chlorine, bromine, iodine and fluorine atoms, and the alkoxy groups include, for example, methoxy,
There are various groups such as ethoxy, bromoxy, and butoxy, and examples of amino groups include amino, mesylamino, dimeplylamino, and diexylamino, and examples of acylamide M include, for example, acetamide,
There are various groups such as propionamide, acyloxy groups include, for example, ahythoxy, propionoxy, etc., alkoxycarbonyl groups include, for example, ethoxycarbonylbonyl, and alkoxycarbonylamino groups include, Examples include groups such as ethoxycarbonylamino, propoxycarbonylamino, and butoxycarbonylamino; examples of aryl groups include groups such as phenyl and tolyl; and examples of alkyl groups include preferably lower alkyl groups such as methyl, ethyl, and propyl. The following groups can be mentioned. It is preferable that at least one of Y1 and Y2 and at least one of Y3 and Y4 is an aryl group, and either Yl and Y2 or Y3 and Yl may be connected to form a title. The result is a naphthoxazole ring, e.g. naphtho[1,2
'-d]oxazole, naphtho[2.1-d]oxazole, and naphtho[2.3-d]oxazole are preferably formed within the molecule of the sensitizing dye represented by the general formula (I).

Further, in general formula (II), the above Y5, Y6, Yl
It is preferable that at least one of Y 8 and Y 8 is a chlorine atom, and at least one of Y 5 and Y 6 is preferably a chlorine atom.
It is also preferred that at least one of Yl, Y8, and Y8 is an aryl group. It is also preferable that Y5 and Y6 and Yl and Y8 are respectively connected to form a ring to form a naphthodiazole ring.

Furthermore, examples of the anions represented by X1 and X2e include chloride, bromide, iodide, thiocyanate, sulfamate, methyl sulfate, ethyl sulfate, verchlorate, and pt-toluenesulfonate. When general formulas (I) and (n) each form an inner salt, n and l each represent 1.

Representative compounds represented by formulas (I) and (II) used in the present invention are listed below, but the invention is not limited thereto.

The following margins [Exemplary compounds of general formula (1)] (I-6) (I-7) (1-8') CI-9) (I-10) 1, 1 (CH2)4 SO3(CH2)4SO3H( 1-IG
) (I-zo) (I-24 (1-2g) (I-31) [Exemplary compounds of general formula (n)] (ll-1) (■-2n (ll-3) (CH2J3803 Na ( n-10) O3e (positive-27) The general formula (I) or general formula (I) used in the present invention
The compound of the present invention, which is a sensitizing dye represented by I), can be synthesized by a known method.
Compounds, Interscience Publishers, New York (F.M., Hamer”The Cy
anine Dyes andRelated C
”, InterscienceP
publisher, New York) (1
964), those skilled in the art can easily synthesize them, and those not shown in the examples can be similarly synthesized by similar methods.

In the present invention, spectral sensitization is carried out by adding the compound of the present invention to a silver halide emulsion containing the silver halide grains of the present invention shown below. The above compound of the present invention may be added at any time such as at the start of chemical ripening (also called second ripening) of the silver halide emulsion, during the course of ripening, after the end of ripening, or at an appropriate time prior to coating the emulsion. do not have.

Furthermore, as a method for adding the compound of the present invention to the above-mentioned photographic emulsion, various conventionally proposed methods can be applied. For example, as described in U.S. Pat. No. 3,469,987, a sensitizing dye is dissolved in a volatile organic solvent, the solution is dispersed in a hydrophilic colloid, and this dispersion is added to an emulsion. You may do so. Still further, the sensitizing dyes, which are compounds of the present invention, can be dissolved individually in the same or different solvents, and the solutions can be mixed before being added to the emulsion, or they can be added separately.

As a solvent for adding the compound of the present invention to a silver halide emulsion, water-miscible solvents such as methyl alcohol, ethyl alcohol, and acetone are preferably used.

When the compound of the present invention is added to a silver halide emulsion, the addition rate is IX per mole of silver halide, respectively.
10-5 moles to 2.5X 1Q-2 moles, preferably 1. OX 1Q - Shock moles to 1. OXiQ-
It is 3 moles. and the preferred use of the compounds of the invention m
The ratio of the compound represented by general formula (II) is in the range of 0.1 to 10, with the compound represented by general formula (I) being 1.

The compounds of the present invention can also be used with a sensitizing dye or a supersensitizer.

The photosensitive silver halide used in the close-up V photosensitive material of the present invention has a silver iodide content of 4 mol% to 40 mol%, more preferably a silver iodide content of 4 mol% to 20 mol%. 7%.

If the silver iodide content exceeds the range of 4 mol% to 40 mol%, if it is less than 47 mol%, there will be little thermal fog, but disadvantages such as low photographic sensitivity will appear; If it exceeds 40 mol %, it becomes difficult to obtain crystals with a uniform silver iodide content in the silver halide grains, and furthermore, there are disadvantages such as large thermal fog.

The average grain size of the photosensitive silver halide grains used in the present invention is 0.4 μm or less. More preferably 0.01μm
~0.4 μm, more preferably 0.05 μm
~0.44m.

The average grain size of the silver halide grains used in the present invention is 0.
4. If it exceeds czm, even if a highly sensitive emulsion layer is obtained, there is a marked tendency for the density to decrease in a dye image formed by heat development.

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. A typical method is Loveround's "Particle Size Analysis Method JA."

S, T, M, Symposium on Light Microscopy, 1955, pp. 94-122, or "Theory of the Photographic Process", Mies and James, 3rd edition, published by Macmillan (19 [36)]. It is described in Chapter 2. 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 iodobromide and silver chloroiodobromide.

The photosensitive silver halide containing silver iodide used in the present invention is described in the book "Himy et Physique Photographic" by P. Gerafkides (published by Ball Montell).
(P, Glafkides, Qhimie etp.
hysique Photographique,
Paul Montel) (1967), G.F. Duffin, Photographic Emulsion Chemistry (The Focal Press) (
G., F., Duffin.

Photographic Emulsion Che
Mistry, The Focal Press
) (1966), Bui El Celikman et al., Making and Coating Photographic Emulsions (The Focal Press)
(V, L, Zelikman et al.

Making and Qoating Photo
graphicEnulsion, The Fo
Cal Press) (1964).

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. As one of the simultaneous mixing methods, the Chondrald double jet method can be used, in which the pA (l) 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 half-sized 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. An emulsion consisting of a photosensitive silver halide consisting of a group of photosensitive silver halide grains with uniform grain morphology and small variation in grain size. The grain size distribution of the monodisperse emulsion (hereinafter referred to as a monodisperse emulsion) shows an almost normal distribution, the standard deviation can be easily determined, and when the breadth of the distribution is defined by the relational expression, it is found that The preferred distribution width is 15%
or less, and more preferably monodispersity with a distribution width of 10% or less.

More preferred photosensitive silver halide grains used in the present invention are core/shell type having a surface latent image type shell.

A core/shell type photosensitive silver halide emulsion which is more preferably used in the present invention can be produced by coating monodisperse photosensitive silver halide grains as a 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 Pi constant. Furthermore, a silver halide emulsion containing highly monodisperse photosensitive silver halide was developed in Japanese Patent Application Laid-open No. 5
The method described in No. 4-48521 can be applied. In a preferred method, an aqueous gelatine solution containing iodobromide and an ammoniacal silver nitrate aqueous solution are added to an aqueous gelatin solution containing silver halide seed particles while changing the addition rate as a function of time. It is manufactured by a method. At this time, by appropriately selecting the time function of the addition rate, I)H, I)Ag, temperature, etc., it is possible to prepare a silver halide emulsion containing highly monodisperse silver halide grains for the core. can.

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 covering the core is preferably 0.05% to 90%, more preferably 1% to 90% of the silver halide grain size. It is in the range of 80%. In the silver halide composition of the core, the silver iodide content is preferably 4 mol% to 201 mol%, and in the shell silver halide composition, 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 field of photography. 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 is coexisted with the organic silver salt described below, and photosensitive silver halide is formed in a part of the organic silver salt. You can also do that. The photosensitive silver salt forming component used in this preparation method is an inorganic halide, for example, a halide represented by MXn (where M is an H atom, NH4
It represents a group or a metal atom, X represents C2, 3r or ■, n represents 1 when M is an H atom or an NH4 group, and represents its valence when M is a metal atom. 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, lead, antimony, bismuth, chromium, molybdenum, tungsten, manganese, rhenium, Examples include iron, cobalt, nickel, rhodium, palladium, osmium, iridium, platinum, and cerium. ), halogen-containing gold forceps (e.g., 2 Pt
Cff1s, ni2 PtBr s, HA
U C24.

(NH4)2 1r Cff16. (NH+)3
1r Cff16.

(NH4)2 Ru Cff1s, (NH+)
3 Ru Cj2s.

(NH4>2 Rh Cff1s (NH4)3
Rh Br6, etc.), onium halides (e.g.
Quaternary ammonium halides such as tetramethylammonium bromide, trimethylphenylammonium bromide, cedylethyldimethylammonium bromide, 3-methylthiazolium bromide, trimethylbenzylammonium bromide, quaternary phosph-4nium such as tetraethylphosphonium bromide halide, benzylethylmethylsulfonium bromide,
tertiary sulfonium halides such as 1-ethylthiazolium bromide), halogenated hydrocarbons (e.g. iodoform, bromoform, carbon tetrabromide, 2-bromo-
2-methylpropane, etc.), N-halogen compounds (N-chlorosuccinimide, N-bromosuccinimide, N-
Bromophthalimide, N-bromoacetamide, N-
Iodosuccinimide, N-bromophthalazinone, N-
Chlorophthalazinone, N-bromoacetanilide, N,
N-dibromobenzenesulfonamide, N-bromo-N
-Methylbenzenesulfonamide, 1,3-dibromo-
4,4-dimethylhydantoin, etc.), 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 various methods, and the amount used is preferably 0.001 g to 50 g per 1f per layer, more preferably, It is 0.1 g to 10 g.

The heat-developable photosensitive material of the present invention uses photosensitive silver halide having a silver iodide content of 4 to 40 mol % and an average grain size of 04 μf11 or less as described above, and further has a composition represented by the general formula (I). and at least one compound of the general formula (11
It is characterized in that it is used in combination with at least one of the compounds represented by [).

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 image by heat development, and color types that include a dye-providing substance. In this latter color type, further monochromatic, e.g., monochromatic, with a black dye-donor or any other monochromatic dye-donor; polychromatic, e.g.
Examples include heat-developable color photosensitive materials that develop yellow, cyan, and magenta colors. In the color type, 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) It contains a reducing agent, (3) a binder, and (4) an organic silver salt.

In addition, in the color type that forms a dye 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, (4) an organic silver salt, and (5) a dye-providing substance. 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. The dye-providing substance (5) may be contained in two or more photosensitive layers as long as they can react with each other, such as by containing the dye-providing substance (5) in the other layer adjacent to this photosensitive layer.

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

In the same way as for the close observation@photosensitive layer of the present invention, coating solutions for the protective layer, intermediate layer, undercoat layer, back layer, and other photographic constituent layers are prepared, and the coating solutions are prepared using the dipping method, air knife method, The photothermographic material can be prepared by various coating methods such as a coating method or a hopper 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 3 to 20 μm. It is.

↓Margin 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. 44-26582, 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 valmidate, 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. 45
-12700, 45-18416, 45-22
No. 185, JP-A-52-31728, JP-A No. 52-137
No. 321, JP-A-58-118638, JP-A No. 58-11
In of imino groups as described in various publications such as No. 8639, for example, benzotriazole silver, 5-nitrobenzotriazole silver, 5-chlorobenzotriazole silver,
5-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
, 2,44 lyazole silver, saccharinated, phthalazinone silver, phthalimide silver, etc., 2-mercaptobenzoxazo-/silver, mercaptooxadiazole silver, 2
-Silver mercaptobenzothiazole, silver 2-mercaptobenzimidazole, 3-mercapto-4-phenyl-1
, 2,4-triazole silver, 4-hydroxy-6-methyl-1,3,3a, 7-chitrazaindene silver and 5-
Examples include silver methyl-7-hydroxy-1,2,3,4,6-pentazaindene. 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 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.
, No. 761,270, No. 3.764.328, and R D No. 12146, No. 3.764.328,
15108, same No.

Examples include p-phenylenediamine and p-aminophenol developing agents, phosphoramidophenol and sulfonamidophenol developing agents, and hydrazone color developing agents described in JP-A No. 15127 and JP-A-56-27132, etc. . Also, U.S. Patent No. 3,
342,599, 3.719.492, JP-A-53-135628, and JP-A-54-79035, etc., 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 represent may be closed to form a heterocycle. R3, R't-R5'' and R6- are a hydrogen atom, a halogen atom, a hydroxy group, an Amimu L alkoxy group, an acylamido group, a sulfonamide group, an alkylsulfonamide group, or a carbon atom number 1 which may have a substituent. to 30 (preferably 1 to 4) alkyl groups, R3 and R' and R' and R2 may each be ring-closed to form a heterocycle. M is an alkali metal atom, an ammonium group, a nitrogen-containing organic Represents a base or a compound containing a quaternary nitrogen atom.

The nitrogen-containing organic base in the general formula (1) is an organic compound containing a nitrogen atom that exhibits basicity capable of forming a salt with an inorganic 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. Further, as the salt of the nitrogen-containing organic base, the above-mentioned unmineralized salts of the organic base (eg, hydrochloride, 5A salt, nitrate M salt, 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) (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) (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, Methoden der Organitsien Hemi-2 Band XI/2 (Houben
-Weyl, Methoden der Qrgan
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-aminophenol, etc.), sulfonamidophenols [e.g. 4-
Benzenesulfonamidophenol, 2-benzenesulfonamidophenol, 2,6-dichloro-4-benzenesulfonamidophenol, 2.6-dipromo 4-
(1)-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, -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'-dimethoxy-1,1'-dihydroxy-2,2
7-binaphthyl, bis(2-human Oxy-1-naphthyl)methane, etc.], methylene bisphenols [e.g.
1-bis(2-hydroxy-3,5-dimethylphenyl)-3゜5.5-trimethylhexane, 1.1-bis(
2-hydroxy-3-tert-ablu-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-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-butylphenyl)propane, 2,2-bis(4- and droxy-3,5-di-tert)
t-butylphenyl)propane, 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 R1/1 silver salt, and the types of other additives, but it is usually about 1 mole of photosensitive silver halide. The amount ranges from 0.01 to 1500 mol, preferably from 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 the following binder described in Japanese Patent Application No. 104249/1982.

This binder includes gelatin and vinylpyrrolidone polymer. The vinyl pyrrolidone polymer may be polyvinyl pyrrolidone, which is a homopolymer of vinyl and lolidone, or may include a copolymer or graft copolymer of vinyl pyrrolidone and one or more other monomers that can be copolymerized. . ). These polymers can be used regardless of their degree of polymerization. Polyvinylpyrrolidone may be substituted polyvinylpyrrolidone, and preferred polyvinylpyrrolidone has a molar mass of 1.000 to 40
It is of 0.000. 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. ,
Examples include vinyl monomers such as vinyl alkyl ethers, but it is preferable that polyvinylpyrrolidone accounts for at least 20% (9% by weight, same hereinafter) of the composition ratio.

Preferred examples of such copolymers include those 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, 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 a mixture of polyvinylpyrrolidone with a molecular weight of 1,000 to 400,000 and one or more other polymeric substances, gelatin and a molecular weight of 5,000 to 400,
000 vinylpyrrolidone copolymer and one or more other polymeric substances is preferred. Other polymeric substances that can be used include polyvinyl alcohol, polyacrylamide, polymethacrylamide, polyvinyl butyral, polyethylene glycol, polyethylene glycol ester, or 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 usage of the binder is usually o, osg to 50 g relative to ITA' per layer, preferably 0.117 g.
~10g.

The support used in the heat-developable photosensitive material of the present invention includes:
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-mentioned synthetic plastic films. Examples include a support provided with anti-mW.

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, same N 0.15734, same N O
, 15776, JP-A-56-130745, JP-A No. 56-130745.
Alkali release agents such as urea and guanidium trichloroacetate described in 132332M- etc.,
12700, US Pat. No. 3,667,9
Non-aqueous polar solvent compound having 100+, -802-, -8o- groups described in No. 59, U.S. Patent No. 3,438.77
Meltformer-1 described in US Pat. No. 3,666.
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, JP-A No. 49-5019, JP-A No. 49-5020, JP-A No. 49-91
No. 215, No. 49-107727, No. 50-2524
No. 50-67132, No. 50-67641, No. 50-114217, No. 52-33722, No. 52
-99813, No. 53-1020, No. 53-551
No. 15, No. 53-76020, No. 53-125014
No. 54-156523, No. 54-15652
No. 4, No. 54-156525, No. 54-1565
No. 26, No. 55-4060, No. 55-4061,
Publications such as No. 55-32015 and West German Patent No. 2.
No. 140.406, No. 2,147,063, No. 2
．． No. 220,618, U.S. Pat. No. 3,080.254, U.S. Pat. No. 3,847.612, U.S. Pat.
No. 3,994,732, No. 4.123.28
2@, phthalazinone, phthalimide, pyrazolone, quinazolinone, N-hydroxynaphthalimide, benzoxazine, naphthoxazinedione, which is a compound described in each specification such as No. 4,201,582.
3-dihydro-phthalazinedione, 2,3-dihydro-
1,3-oxazine-2,4-dione, oxypyridine, aminopyridine, hydroxyquinoline, aminoquinoline, isocarbostyryl, sulfonamide, 2H-1,
These include 3-benzothiazine-2,4-(3H) dione, benzotriazine, mercaptotriazole acid, naphthalic acid, phthalamic acid, etc.
a mixture of one or more with an imidazole compound,
Also, mixtures of at least one acid or acid anhydride such as phthalic acid and naphthalic acid and a phthalazine compound, furthermore, phthalazine and maleic acid, itaconic acid, quinolinic acid,
Examples include combinations of gentisic acid and the like. Also, JP-A-58-189628, JP-A No. 58-193460
3-amino-5-mercapto-1 described in the publication No.
．． 2.4-)-Riazoles, 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, 49-97643, 50-1
01 (No. 119, No. 49-130720, No. 50-
No. 123331, No. 51-47419, No. 51-57
No. 435, No. 51-78227, No. 51-1043
No. 38, No. 53-19825, No. 53-20923, No. 51-50725, No. 51-3223, No. 51
-42529, 51-81124, 54-51
Publications such as No. 821 and No. 55-93149, as well as British Patent No. 1,455,271 and U.S. Patent No. 3,885.
, No. 968, No. 3, No. 700, 457, No. 4,
No. 137,079, No. 4,138,265, West German Patent No. 2,617,907, etc., or oxidizing agents (for example, N-halogen acetamide, N-halogenosuccinimide, perchloric acid and its salts, inorganic peroxides, persulfates, etc.), or M and its salts (e.g., sulfinic acid, lithium laurate, rosin, diterpene acid,
thiosulfonic acid, etc.), or sulfur-containing compounds (e.g., mercapto compound-releasing compounds, thiouracil, disulfide, simple sulfur, mercapto-1.2.4-triazole, thiazolinthion, polysulfide compounds, etc.), others, oxazolines, 1,2 .

Examples include compounds such as 4-triazole and phthalimide. Furthermore, as another antifoggant, JP-A-59-111
Thiol (preferably thiophenol compounds) compounds described in No. 636 are also effective.

Other antifogging agents include Japanese Patent Application No. 59-5s5
Hydroquinone derivatives described in os@ (for example, G-1
-octylhydroquinone, dodecanylhydroquinone, etc.) or hydroquinone derivatives described in Japanese Patent Application No. 1983-66380, and benzotriazole derivatives (e.g., 4-sulfobenzotriazole, 5-carboxybensitriazole, etc.) are preferably used in combination. can.

Also, especially as a stabilizer, 51!13! A later printout prevention agent may also be used at the same time, for example, as disclosed in JP-A-48-45
No. 228, No. 50-119624, No. 50-12
Halogenated hydrocarbons described in No. 0328 and No. 53-46020, specifically tetrabromobutane, tribromoethanol, 2-bromo-2-tolylacetamide, 2-bromo-2-tolylsulfonylacetamide, 2-tribromomethylsulfonylbenzothiazole,
Examples include 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, US Pat. No. 3,824,103, US Pat. No. 3,844, 788 @ isothiuronium stabilizer precursor described in each specification, and US Pat. No. 3.669.670, US Pat. No. 4,012, No. 260,
It may contain activator stabilizer breaker etc. described in the specification of 4.060.420.

Also, sucrose, N84 Fe (804)2 ・1
A water release agent such as No. 2820 may be used, and furthermore, water may be supplied and heat development may be carried out as in JP-A-56-132332.

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 photosensitive material of the present invention is a color type, the dye-providing substance fη is included.

Dye-providing substances that can be used in the present invention will be explained below. The dye-donating substance may be any substance as long as it participates in the reduction reaction of the photosensitive silver halide and/or the organic silver salt used as necessary and can form or release a diffusible dye as a function of the reaction. Depending on their reaction form, negative-acting dye-donors act on a positive function (i.e., form a negative dye image when negative-working silver halide is used) and positive-acting substances act on a negative function. It can be classified as a dye-providing substance (that is, it forms 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 special R[
No. 57-179840, No. 58-116537, No. 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 mentioned.

In the following margins, exemplified dye-providing substances 0C16H33(n) CrHu(t) Other reducing dye-releasing compounds include, for example, general formula (3)
Examples include compounds represented by:

General formula (3) In the formula, AI and A2 each represent a hydrogen atom, a hydroxy group, or an amine 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, Cp+ is an organic group (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 CD1 and J is cleaved by the reaction of the reducing agent with the oxidized product. nl is O
or 1, and Dye has the same meaning as defined by general formula (2). Further, CI) 1 is preferably substituted with various ballast groups in order to make the coupled dye-releasing compound non-diffusible, and the ballast group has 8 carbon atoms depending on the form of the photosensitive material used. or more (more preferably 12 or more) organic groups, or hydrophilic groups such as sulfo groups or carboxy groups, or 8 or more (more preferably 12 or more) carbon atoms and hydrophilic groups such as sulfo groups or carboxy groups. It is a group that also has a 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,
The various specifications of Japanese Patent Application No. 59-104901 are reprinted, and the following compounds may be mentioned, for example.

Exemplary dye-donor substances ■ OCR.

■ As a coupling 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, for the sake of 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, CD2 and F have the same meanings as defined in general formula (5), Y represents an alkylene group, arylene group, or aralkylene group, and 2 represents O or 1. In the formula, Z represents a divalent organic group, and 1 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
No. 2507 (7) Each Akira m@ etc., and examples thereof include the following compounds.

Exemplary dye-donor substance 18nH OOH [Phase] C,, H8゜Polymer 0H x: 60% by weight y: 40% by weight CH3 :Fo only↑λ In the above general formulas (4), (5) and (6), CD
More specifically, the coupler residue defined by + or CI)2 is preferably a group represented by the following general formula.

General formula (7) General formula (8) General formula ((
? ) General formula (10) General formula (/3)
General formula (/+) General formula (E)
General formula (16) In the following margin formula, R7, Rg, R? and RIO are hydrogen atoms, halogen atoms, alkyl groups, cycloalkyl groups, aryl groups, acyl groups, alkyloxycarbonyl groups, aryloxycarbonyl groups, alkylsulfonyl groups, arylsulfonyl groups, carbamoyl groups, sulfamoyl groups, acyloxy groups, amiLL alkoxy group,
It represents an aryloxy group, a cyano group, a ureido group, an alkylthio group, an arylthio group, a carbo, an xy 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, or a nitro group. ,
It may be substituted with an alkyl group, an aryl group, an aryloxy group, an acyloxy group, an acyl group, a sulfamoyl group, a carbamoyl group, an imide group, a halogen atom, or the like.

These substituents are selected depending on the purpose of Cpl and CI)2, and as mentioned above, in <Cp+, one of the substituents is preferably a ballast group, and in CI)2, it is preferable that one of the substituents is a ballast group. Molecule ■ is 700 to increase sex.
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),
R'' represents an alkyl group or a hydrogen atom, R/3 represents an oxygen atom or R'2 (does not represent -N-) or -802-, r represents 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
It is described in specifications such as No. 66954 and No. 59-154445, and includes, for example, the following compounds.

Exemplary dye-donating substance ■ CH3 ■ Another positive dye-donating substance is represented by the following general formula (18)
There are compounds that lose their dye-releasing ability when oxidized, such as the compound represented by:

General formula (1B) R'1 In the formula, W2 represents a group of atoms necessary to form a benzene ring (which may have an @ substituent on the ring), and R'
, r, E, and D'ie 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 the specifications of No. 9-124329, No. 59-154445, etc., and includes, for example, the following compounds.

Illustrative dye-providing substances
Examples include compounds represented by 19).

General formula (19) In the above formula, W2, R″, and Dye have the same meanings as defined in general formula (18).

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

Exemplary dye-providing substances @ OH Below margins General formulas (2), (3), (4), (17) (18
) and (19), the residue of the diffusible dye represented by Dye will be explained in further detail. Due to the diffusivity of the dye, the residue of the diffusible dye has a molecular number of 800 or less, more preferably 6001 or less, and includes azo dyes, azomethine dyes, anthraquinone dyes, naphthoquinone dyes, and subryl. Examples include residues of dyes, nitro dyes, quinoline dyes, carbonyl dyes, phthalocyanine dyes, etc. These dye residues may be in the form of temporary short wavelengths that can be multicolored during heat development or transfer. For the purpose of increasing the light resistance of images, dye residues are used, for example, in JP-A-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 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 rate can be 0.005 (1 to 50 g, preferably 0.1 g to 10 a) per 1 f.

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. Cresylbosphate, etc.) and then ultrasonically dispersed or dissolved in an alkaline aqueous solution (e.g., 10% sodium hydroxide aqueous solution, etc.) and then neutralized with mineral vI (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 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 that can be used for normal viewing@photosensitive materials can be used, such as contacting with a heated block or plate, contacting with a heated roller or drum, or passing through a high temperature atmosphere. Alternatively, it is also possible to use high frequency heating, or furthermore, it is also possible 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 energization or a strong magnetic field.

There are no particular restrictions on the heating pattern, including methods of preheating (breheating) and then reheating, heating at a high temperature for a short time, or at a low temperature for a long time, continuously increasing, decreasing, or repeating, and even discontinuously. Although 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 photothermographic material is normally exposed at a temperature of 80°C after vertical exposure.
1 second to 240 seconds, preferably 1.5 seconds to 1 at a temperature range of ~250°C, preferably 100°C to 200°C
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
28, No. 51-80226, etc.), but Japanese Patent Application Laid-Open No. 59-136733, Research Disclosure No. 16407, No. 1640
A bleach-fixing sheet such as that described in No. 8, No. 16414 may also be used.

In addition, when the photosensitive material is a color type using a dye-providing substance, the image receiving member described below and the photosensitive layer side of the exposed photothermographic material of the present invention are stacked on top of each other. Normally 80℃~200℃
, preferably at a temperature in the range of 120° C. to 170° C., for 1 second to 180 seconds, preferably for 1.5 seconds to 120 seconds, and is transferred to the image receiving member at the same time as color development. Moreover, you may perform preheating in the temperature range of 70 degreeC - 180 degreeC 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 sensitizers 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. Nos. 2,548,564 and 2,48
No. 4,430, No. 3,148,061, No. 3.756
．． 814, vinylpyridinium cationic polymers as disclosed in U.S. Pat. No. 2,675,316, polymers containing dialkylamino groups as disclosed in U.S. Pat. No. 2,882,156, Aminoguanidine derivatives, JP-A-1987
Covalently Reactive Polymers Described in US Pat. No. 3,625,694, Id. 3,859
．． 096, British Patent No. 1,277.453, British Patent No. 2,
No. 011,012, a mordant capable of crosslinking with gelatin, etc., and U.S. Pat.
．． 721.852, 2.798, and 063; water-insoluble mordants disclosed in JP-A-50-61228; and U.S. Patent No. 3.78.
8.855, West German Patent Application (OLS) No. 2,843,
320, JP-A No. 53-30328, JP-A No. 52-155
No. 528, No. 53-125, No. 53-1024,
No. 54-74430, No. 54-12.1726, No. 55-22766, U.S. Patent No. 3,642.482, No. 3.488.706, No. 3.557.0136
No. 3,271,147, No. 3,271.148, Special Publication No. 55-29418, No. 56-36414,
No. 57-12139, RD 12045 (1974
Examples include various mordants disclosed in 2010).

Particularly useful mordants are polymers containing ammonium salts,
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-n-hexyl-N-vinylbenzylammonium chloride, and 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.

An example of the heat-resistant organic polymer substance is a molecular weight of 2.0.
00 to 85,000 polystyrene, polystyrene derivatives having substituents having 4 or less carbon atoms, polyacetals such as polyvinylcyclohexane, polyvinylbenzene, polyvinylpyrrolidone, polyvinylcarbazole, polyallylbenzene, polyvinyl alcohol, polyvinyl formal, and polyvinyl butyral; Polyvinyl chloride, chlorinated polyethylene, polytrichloride 1-dylene fluoride, polyacrylodi-1-lyl, poly N,N-dimethylacrylamide, poly with 0-cyanophenyl group, pentachlorophenyl group and 2,4-dichlorophenyl group Acrylate, polyacryl chloroacrylate, polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polyisopropyl methacrylate,
Polyisobutyl methacrylate, poly tert-butyl methacrylate, polycyclohexyl methacrylate, polyethylene glycol dimethacrylate, poly-2
- Polyesters such as cyano-ethyl methacrylate and polyethylene terephthalate, polycarbonates such as polysulfone and bisphenol A polycarbonate,
Examples include polyanhydrides, polyamides, and cellulose acetates. In addition, Polymer Handbook 2nd edition (Polymer Handbook
2nd ed,), G. Brand Rap,
EH Inmargt TIA (J, Br
andrup, E, H, Immer! Ju
t), John Wiley & Sons Publishing (J
Also useful are synthetic polymers with glass transition temperatures of 40°C or higher, such as those described in Wiley & Sons. Even if these polymeric substances are used alone,
Moreover, a plurality or more may be combined and used 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).

Further, as an image-receiving layer, an opaque F11 containing titanium dioxide or the like dispersed in gelatin is placed on a receiver layer on a transparent support.
A reflective layer) may also be provided. 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] Silver bromide emulsion-A for comparison was prepared by the following method.

At 50°C, JP-A-57-92523, JP-A-57-92523;
Using the mixing agitator shown in the specification of No. 92524,
Ossein gelatin 20g 1 Distilled water 100 (H12) and ammonia dissolved in solution (A) containing 1.1 mole of potassium bromide SOOVG solution (B) containing 1 mole of silver nitrate and ammonia An aqueous solution soo, g of solution (C) was simultaneously added while keeping 1) A (I constant. The shape and size of the emulsion grains to be prepared were as follows: l) H, l)
It was adjusted by controlling the addition rate of 80 and liquids (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 μm and a monodispersity of 8%.

This emulsion was washed with water and desalted. The yield of '7L agent is 8001
It was g.

[Iodoodor (Preparation of Arsenic Emulsion 1) Silver halide emulsions containing three types of photosensitive silver halides having different silver iodobromide contents 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 ossein gelatin 20 (+), distilled water 10 QOd, and ammonia were dissolved using the mixing and stirring method described in the specification of No. 92524. potassium oxide 4.98g,
Potassium bromide 13IQ, potassium iodide 6 for emulsion C
．． 64 (1, potassium bromide 131g, potassium iodide for emulsion 11.62 (J, potassium bromide 131g)
(B) solution containing 500 iN of an aqueous solution containing 1 mol of nitric acid and 500 iN of an aqueous solution containing ammonia (
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 controlling the pH, the addition rate of I) A(] and (8) and (C). Emulsions having different silver contents were prepared. (The monodispersity of each emulsion was 9%). These emulsions were washed with water and desalted.

The yield of each emulsion was 80 (hc).

The average grain size and silver iodide content of each silver halide of each emulsion A to D thus prepared, as well as the potassium iodide and potassium bromide concentrations in each (B) solution are shown in Table 1 below. .

Table-1 All-in-cis lower [Preparation of core/shell type silver iodobromide emulsions] Three types of core/shell type emulsions E and F with different silver iodide contents and average grain sizes
, G 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 gelatin, 1000 iQ of distilled water, and ammonia were dissolved using the mixing agitation chamber shown in the specification of No. 92524 (potassium iodide for emulsion E). 11.62 Q
, potassium bromide 131g, potassium iodide 11.62g, potassium bromide 131(] for emulsion E, potassium iodide 33.2(], potassium bromide 119g for emulsion G)
) containing 500 d of solution (B) and 11'I
500 volumes of solution (C) containing 1 mol of acid silver and ammonia were simultaneously added while keeping the pAg constant. The particle shape and average particle size of the core emulsion to be prepared are determined by pH, 1
)A(+) and by controlling the addition speed of liquids (B) and (C).In this way, core emulsions with the same regular octahedral shape, different average grain sizes, and different silver iodide contents were prepared. (The monodispersity of each core emulsion was 8%)
Next, using the silver halide grains obtained above as cores, a silver halide shell is applied to the core in the same manner as above (however, each potassium iodide concentration and potassium bromide concentration of the shell solution (B) is different from that of the emulsion). Potassium iodide 3.32 g, potassium bromide 131i; l for Emulsion E, potassium iodide 3.32 g, potassium bromide 131g for Emulsion G, 131CI)
Core/shell type silver halide emulsions having the same regular octahedral shape, different average grain sizes, and different silver iodide contents were prepared by coating.

Each of these emulsions was washed with water and desalted. The yield of each emulsion was 800 d.

The average grain size and silver iodide content of each core/shell type silver halide emulsion E, F, and G prepared in this way are shown in the table below.
Shown in 2.

>Xl” Complete white [Preparation of organic silver salt dispersion-1] 28.8 g of 5-methylbenzotriazole obtained by reacting 5-methylbenzotriazole and silver nitrate in a water-alcohol mixed solvent and poly(N -vinylpyrrolidone) and 1.33 (l) of 4-sulfobenzotriazole sodium salt were dispersed in an alumina ball mill and brought to pH 5.5 to 20 (hN).

[Preparation of photosensitive silver halide dispersion] Silver halide emulsion-D prepared above was mixed with the compound of the present invention [sensitizing dye (I> and sensitizing dye (■))] in Table 3 below.
and 4-hydroxy-6-methyl-
ThioT in the presence of 1,3,3a,7-tetrazaindene
A photosensitive silver halide emulsion dispersion having the following composition was prepared by sulfur sensitization treatment using if=M sodium.

Silver halide (in terms of silver) 381 g Gelatin 85/2820 I [Preparation of dye-donor dispersion-1] Exemplary dye-donor substance O 35.5 g and the following hydroquinone compound s, oog were mixed with 200 g of ethyl acetate. , mixed with gelatin aqueous solution 720i12 containing 30.5 g of alkanol After ethyl acetate was distilled off, the pH was adjusted to 5.5 to 195.

Hydroquinone compound H [Preparation of reducing agent dispersion] Exemplary reducing agent (R-11) 23.3 g, the following development accelerator 1.101; l, poly(N-vinylpyrrolidone) 1
4.6Q, the following fluorosurfactants o and sog were dissolved in water and adjusted to pH 5.5 to 250i.

Surfactant C1m, 71 = z non+x 3 ) [Preparation of photothermographic material-1] 12.5 mm of the organic silver salt dispersion prepared above, 6.00 tff of the above silver halide dispersion, and dye-providing substance dispersion. Liquid-1
39.8, 12.5 iu of reducing agent dispersion-1 was mixed, and a hardening agent solution (tetra(vinylsulfonylmethyl)methane and taurine were reacted at a ratio of 1:1 (weight ratio) to form phenyl 2.50 mj2 of carbamoylated gelatin (dissolved in a 1% aqueous solution to give a concentration of 3% tetra(vinylsulfonylmethyl)methane) and 3 mj of polyethylene glycol 300 (Kanto Kagaku) as a hot solvent.
．． 80 (thickness after adding 180 liters and undercoating)
A film of 1.76 g/12 μm of photographic polyethylene terephthalate was coated with 1.76 g/12 g of silver, and on top of that was a mixture of polycarbamoylated gelatin and poly(N-vinylpyrrolidone). 1^5 layers were provided, and heat-developable photosensitive materials of Sample Nos. 1 to 12 shown in Table 3 below were prepared.

[Preparation of image receiving member-1] Polyvinyl chloride (n-1, 10
Apply a tetrahydrofuran solution of 0.0, Wako Tsumugi Pharmaceutical),
The polyvinyl chloride was adjusted to 120/m'.

The photothermographic material was exposed to 1,600 C, M, and S through a step wedge, and together with the image receiving member, the photothermographic material was exposed to light of 1,600 C, M, and S.
．． 3M Company) for 1 minute at 150°C, and then quickly peel off the photothermographic material and the image receiving member. The image was obtained.

On the other hand, the same exposed photosensitive material was developed at 20''C for 3 minutes using a developer having the following composition, followed by stopping, fixing, washing with water, and drying to obtain black and white &.

Table 3 shows the sensitivity of the black and white image and the sensitivity of the magenta transferred image obtained by J3 and heat development in relative values.

The sensitivity of the black and white image of comparative sample No. 9 was set at 1oo, and the sensitivity was determined at the point of fog+0.2.

[Developer composition] Metol 2g anhydrous sodium sulfite 40 (]Hydroquinone
4g sodium carbonate monohydrate
28 g potassium bromide
Add 1° water to make 1.

As is clear from Margin Table 3 below, only the sensitizing dye (I) or only the sensitizing dye (II>) of the compounds of the present invention is added to the silver halide emulsion containing the photosensitive silver halide of the present invention. Compared to the comparative samples (N o, 9 to 12) used, the samples (N o, 1 to 8) using a combination of the sensitizing dye (1) and the sensitizing dye (ff) of the compound of the present invention were as follows: It can be seen that the desensitization caused by heat development is small, and the sensitizing effect on photosensitive silver halide is also good, making it a highly sensitive heat-developable photosensitive material.

Example 2 In Example 1, the silver halide emulsion shown in Table 4 below and the compound of the present invention [sensitizing dye (I) and sensitizing color 1 (
II)] A photosensitive silver halide dispersion (sample F8AN0°13-31) was prepared in the same manner except that the combination was changed to the following. A magenta transfer image and a black and white image were obtained by preparing a heat-developable photosensitive material and an image receiving member, exposing and developing the heat-developable photosensitive material in the same manner as in Example 1.

Table 4 shows the relative sensitivity of black and white images and magenta images. Comparison test f! The sensitivity of the black and white machine with IN0.17 is set to 100.
The sensitivity was determined as fog divided by 02.

Furthermore, the maximum density ([)max) determined for a magenta image by color heat development is shown.

As is clear from Margin Table 4 below, a comparative sample (No. 14.15.17.18.20) in which the sensitizing dye (I>, which is a compound of the present invention) and the sensitizing dye (II) are not used in combination ，
21, 23, 24, 26, 27, 29, and 30), a significant decrease in sensitivity is observed due to color thermal development.

Furthermore, even when sensitizing dye (I) and 11-sensitizing dye (II) are used in combination, compared to comparative sample No. 13 in which the photosensitive silver halide is outside the scope of the present invention, sensitizing dye (I) and ( II)
In the sample of the present invention (NO116, 1, 22.28) in which the combination of I understand. Furthermore, among the photosensitive silver halides of the present invention, the sample (No. 19.22) using core/shell type photosensitive silver halide has particularly low desensitization and high magenta 14[)max. It is being On the other hand, even with core/shell type photosensitive silver halide, the grain size was 0.5 μm, which is outside the scope of the present invention (comparative sample) i
t (No, 31>), although the sensitivity is high, the maximum density of the Markenck transfer phenomenon is small and it is found that it cannot be used in practical use.

Example 3 4-hydroxy-6-methyl- 1, 3,
A photosensitive silver halide dispersion having the following composition was prepared by sulfur enrichment with sodium thiosulfate in the presence of 3a,7-tetrazaindene.

Silver halide (in terms of silver) 381 g Gelatin 85 (] / 2820 bags [Preparation of dye-donor dispersion-2] Exemplary dye-donor substance ■ 30. Og, tricresyl phosphate 30.0!II and ethyl acetate 90 0 vQ, mixed with gelatin aqueous solution 460 xR containing surfactant as in Example 1, dispersed with an ultrasonic homogenizer, ethyl acetate was distilled off and water was added to give 50 (hQ).

[Preparation of heat-developable photosensitive material-2] The silver halide emulsion dispersion do, o, L2, 25.0 of the organic silver salt dispersion-1 of Example 1, and 50 of the dye-providing substance dispersion-2. ．． (Mix he and then use polyethylene glycol 300 (Kanto Kagaku) as a hot solvent. 4.2
0g, 10% methanol solution of 1-phenyl-4,4-dimethyl-3-pyrazolidone i, sTh+2 same hardener as in Example 1 3.00 it2 and 10% water-alcoholic solution of guanidine trichloroacetic acid 20.0t
ff1f onto a polyethylene terephthalate film for printing with a thickness of 180 μm that has been undercoated with lp.
Coating is done so that fl is 2.50Q/1', and the following table-
Twelve kinds of heat-developable photosensitive materials (2) of samples No. 0.32 to No. 43 shown in No. 5 were prepared.

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

(1) Fi consisting of polyacrylic acid, (7,00(
]/l') (2) Layer made of cellulose acetate. (4,
00g/v') (3) Sudrene and N-benzyl-N
, a 1:1 copolymer of N-dimedylene-N-(3-maleimidopropyl)ammonium chloride and gelatin.

(Copolymer 3.OOG/TI' Geratin 3.OO
Q, / ,, 2) The above 12 kinds of heat-developable photosensitive materials 1'l
-2, through a step wedge 1,600C
,~1. The image receiving member-2 was exposed to S and heated for 1 minute on a heat block at 150°C, and then immersed in water.
Combine, 50℃, 500g ~ 800 (1/C
When i' was crimped for 30 seconds and immediately peeled off, a yellow step wedge negative image 17 was left on the surface of the image receiving member.

On the other hand, the same exposed photosensitive element was subjected to black development in the same manner as in Example 1 to obtain a black and white image.

Table 5 shows the sensitivity of the above black and white image and the sensitivity of the yellow transfer V obtained by heat development in relative terms.

The sensitivity of the black image of comparative sample N040 was set to 100, and the sensitivity was determined at the point of fog + 0.2.

As is clear from Table 5 below, even in thermal photosensitive materials in which a dye-donating substance is used in place of a reducing dye substance, the halogen Shichikao-7shi agent containing the photosensitive halogen Shichi-Ninji of the present invention, Comparative samples using only the sensitizing dye (T) or only the sensitizing dye (II) among the compounds of the present invention (No. 40 to
43), samples using a combination of sensitizing dye (I) and sensitizing dye (II) of the compound of the present invention (No.
32 to 39) have less desensitization due to heat development and also have a good sensitizing effect on photosensitive silver halide,
It can be seen that this is a highly sensitive photothermographic material.

Example 4 In Example 3, the silver halide emulsion shown in Table 6 below and the compound of the present invention [sensitizing dye (I) and sensitizing dye (■
)] A photosensitive silver halide dispersion was prepared in the same manner except that the combination was changed.

A yellow transfer image and a black and white image were obtained by preparing a heat-developable photosensitive material and an image receiving member, exposing the photosensitive material, and producing the same phenomenon as in Example 3.

Table 6 shows the sensitivity of black and white images and yellow images in relative values. The sensitivity of the black and white image of comparative sample N0148 is set to 100,
The sensitivity was determined based on fog+0.2, and the maximum density [nax] was determined for a yellow image produced by color thermal development.

As is clear from Margin Table 6 below, a comparative sample (No. 45.46.48.49.51) in which the sensitizing dye (1) and the sensitizing dye (It), which are compounds of the present invention, are not used in combination
．． 52.54.55.57.58.60.61),
There is a significant decrease in sensitivity due to color heat development.

Furthermore, even when the sensitizing dye (I) and the sensitizing dye (It) are used in combination, compared to comparative sample No. 13 in which the photosensitive silver halide is outside the scope of the present invention, the sensitizing dye (I> and ( In the samples of the present invention (No. 147, 50, 53, and 5 samples) which combined II) and further used the photosensitive tin halide of the present invention, the desensitization due to the color heat phenomenon was improved, and the material was a good heat-developable photosensitive material. Furthermore, among the photosensitive silver halides of the present invention, the sample using core/shell type photosensitive silver halide (No. 50.53) had the least desensitization and yellow color. A high image [) max is obtained. On the other hand, even with a core/shell type photosensitive silver halide, a comparative sample (
No. 62) has high sensitivity, but the maximum density of the yellow transferred image is low, and it can be seen that it cannot be put to practical use.

Patent applicant Konishiroku Photo Industry Co., Ltd. Representative Patent Attorney Ichinose, Miyau style graduate with QQ Shishi! Wa -Top 1-

Claims (1)

[Scope of Claims] At least one of the silver halide emulsion layers of the heat-developable photosensitive material contains a photosensitive halide having a silver iodide content of 4 to 40 mol% and an average grain size of 0.4 μm or less. 1. A photothermographic material characterized by containing silver particles and a combination of at least one compound represented by the following general formula (I) and at least one compound represented by the following general formula (II). General formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. Represents a carbonyl group, alkoxycarbonylamino group, aryl group, cyano group, alkyl group or carboxyl group, and either Y_1 and Y_2 or Y_3 and Y_4 may be connected to form a ring to form a naphthoxazole ring. . Furthermore, R_1 represents a hydrogen atom or an alkyl group, R_2 and R_3 each represent an alkyl group, X_1^■ represents an anion, and m represents 1
or represents an integer of 2. However, when m represents 1, R_2 or R_3 represents a group capable of forming an inner salt. ] General formula (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, Y_5, Y_6, Y_7 and Y_8 are hydrogen atoms, halogen atoms, hydroxyl groups, alkoxy groups, amino groups, acylamido groups, acyloxy groups, respectively. It represents an alkoxycarbonyl group, an alkoxycarbonylamino group, an aryl group, a cyano group, an alkyl group, or a carboxyl group, and Y_5 and Y_6 and/or Y_1 and Y_3 may each be connected to form a ring to form a naphthodiazole ring. . Further, R_4 represents a hydrogen atom or an alkyl group, R_5 and R_6 each represent an alkyl group, X_2^■ represents an anion, and n
represents an integer of 1 or 2. However, when n represents 1, R_5 or R_6 represents a group capable of forming an inner salt. ]