JP2000089410A - Heat developable image recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developable image recording material having good adaptability for correction of pin holes (opaque adaptability) in an image part after heat development and having good adaptability for heat development. SOLUTION: This recording material has at least one image forming layer containing org. silver salts, reducing agent and photosensitive silver halides on a supporting body, and at least one protective layer formed on the image forming layer. As for the binder in the image forming layer, a polymer latex is used, and as for the binder in the protective layer, a polymer latex containing crosslinking core-shell type latex is used. The gel proportion in the protective layer is 40 to 100 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable image recording material, and more particularly to a photolithographic material.
The present invention relates to a heat-developable image recording material having high-contrast photographic properties, and having good suitability for heat development or correction of pinholes in an image area after heat development (suitability for opaque).

[0002]

2. Description of the Related Art There are many known photosensitive materials having a photosensitive layer on a support and forming an image by exposing the image. Among them, a technique for forming an image by thermal development is mentioned as a system that can simplify environmental preservation and image forming means.

In recent years, in the field of photoengraving, it has been strongly desired to reduce the amount of processing waste liquid from the viewpoint of environmental protection and space saving. Therefore, it is possible to use a laser scanner or a laser imagesetter for efficient exposure,
There is a need for a technique relating to a photosensitive heat-developable material for photoengraving that can form a sharp black image having high resolution and sharpness. These photosensitive heat-developable materials can eliminate the use of solution-based processing chemicals, and can provide customers with a simpler heat-development processing system that does not damage the environment.

[0004] Methods of forming an image by thermal development are described in, for example, US Patent Nos. 3,152,904 and 3,457,075, and US Pat.
Morgan and B.A. `` Thermally Processed Silent System, '' by Shely
ver Systems) A ”(Imaging Processes and Material
s) Neblette 8th edition, Sturge, V.S. Walworth, A .; Editing Shepp, 2nd
P. 1969). Such photosensitive materials are prepared by dispersing a reducible non-photosensitive silver source (eg, an organic silver salt), a catalytically active amount of a photocatalyst (eg, silver halide), and a silver reducing agent, usually in an organic binder matrix. It is contained in. The photosensitive material is stable at room temperature,
When heated to a high temperature (for example, 80 ° C. or higher) after exposure, silver is generated through a redox reaction between a reducible silver source (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure.
The silver formed by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas,
An image is formed.

Conventionally, these types of photothermographic materials have been known. However, most of these photothermographic materials are prepared by applying a coating solution using an organic solvent such as toluene, methyl ethyl ketone, or methanol to form a photothermographic image layer. Has formed. The use of an organic solvent as a solvent has adverse effects on the human body in the manufacturing process and has a problem of emission of organic gases that cause global warming, and is disadvantageous in terms of costs such as the need for solvent recovery and explosion-proof facilities. .

[0006] Such a problem can be solved by using water as a coating solvent. (Hereinafter, a coating method using water as a coating solvent is referred to as “water-based coating”.) For example, JP-A-49-52626,
JP-A-53-116144 discloses an example using a gelatin binder. JP-A-50-151138 describes an example in which polyvinyl alcohol is used as a binder.

However, when such a water-soluble binder is used, dehydration shrinkage and thermal expansion of the binder occur at the same time during thermal development, and the thermal expansion of the binder is different from that of the support. Only unsuitable films are obtained for printing.

This problem can be solved by using a polymer latex. For example, International Patent Nos. W097-4355 and JP-A-8-137045 describe a method for preparing a heat-developable image recording material by aqueous coating using a polymer latex as a binder.

However, in order to uniformly form an image forming layer and a protective layer without deteriorating photographic properties, MFT
It is necessary to use a polymer latex coating solution having a low (lowest film forming temperature), and for this purpose, a polymer latex having a low Tg (glass transition temperature) and / or a film forming aid is used to form a coating film with an appropriate MFT. It is essential that they be formed. However, lowering the MFT softens the coating film after application and drying, and adheres to a heat developing device member (for example, a conveying roller, a guide plate, etc.) at the time of the heat development processing, so that poor conveyance or scratches are likely to occur. It is easy to cause such problems. In addition, a correction liquid using an organic solvent as a solvent is often used for correcting a pinhole of an image after the heat development processing. When these correction liquids are used, the coating film of the correction part may be dissolved or may swell very much to damage the image.

[0010] In general, a technique of cross-linking a polymer with various cross-linking agents has been used for the purpose of improving heat resistance, durability and mechanical properties of the polymer. In general, these techniques often crosslink at high temperatures. In particular, when a super-high contrast agent (nucleating agent) is used to obtain high-contrast photographic characteristics, problems such as high fog and difficulty in achieving high contrast are caused. was there. In addition, many cross-linking agents react with active hydrogen (for example, epoxy groups). Even when a cross-linking agent is added to the protective layer, if the amount is large, the cross-linking agent moves to the image forming layer by diffusion, and There is also a problem that the photographic performance is reduced due to the reaction with the chemicals necessary for the formation. Crosslinking proceeds without deteriorating photographic properties, suitability for thermal development processing, or
There has been a demand for a heat-developable recording material having excellent suitability for correcting an image after heat development.

[0011]

SUMMARY OF THE INVENTION The object of the present invention is to provide a high-contrast, low-fogging good photographic characteristic for photoengraving, especially for a scanner and an image setter, and a heat development process. An object of the present invention is to provide a heat-developable recording material which is excellent in aptitude and correction property (opaque suitability) of an image after thermal development.

[0012]

This object has been achieved by the following means. (1) Thermal development having at least one image forming layer containing an organic silver salt, a reducing agent and a photosensitive silver halide on a support, and at least one protective layer provided on the image forming layer In the image recording material, a polymer latex is used as a binder of the image forming layer, a polymer latex containing a crosslinkable core-shell type latex is used as a binder of the protective layer, and a gel fraction of the protective layer is 40% by weight. A heat-developable image recording material, characterized in that the content is at least 100% by weight. (2) The crosslinkable core-shell type latex used for the protective layer has a functional group in a shell part, and the glass transition temperature of the core part is higher than the glass transition temperature of the shell part. The heat-developable image recording material as described in (1) above, wherein a crosslinking agent having a functional group capable of reacting with a crosslinkable core-shell type latex is used. (3) The crosslinkable core-shell type latex used in the protective layer has a functional group in the shell part, and the glass transition temperature of the core part is higher than the glass transition temperature of the shell part. The heat-developable image recording material according to the above (1), wherein a polymer latex having a functional group capable of reacting with the crosslinkable core-shell type latex is used in the layer. (4) The above (1) to (3), wherein the functional group contained in the crosslinkable core-shell type latex is selected from a hydroxyl group, an isocyanate group, a 2-oxazolinyl group, an N-methylol group and an epoxy group. A heat-developable image recording material according to any one of the above.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The heat-developable image recording material of the present invention has an image forming layer containing an organic silver salt, a reducing agent and a photosensitive silver halide, and has a protective layer on the image forming layer. In addition, as a binder for the protective layer, a polymer latex which enables an aqueous coating which is advantageous in terms of environment and cost is used. In such a heat-developable image recording material, a material containing a crosslinkable core-shell type latex is used as the polymer latex of the protective layer, and the gel fraction of the protective layer is 40%.
By controlling the amount by weight, a heat-developable image recording material having excellent suitability for heat development and opacity while maintaining good photographic performance can be obtained. On the other hand, if the self-crosslinkable polymer latex is not used as the polymer latex, the effects of the present invention cannot be obtained, and if the gel fraction of the protective layer is less than 40% by weight, the suitability for thermal development processing is particularly low. The effect of the present invention cannot be obtained.

The amount of the polymer latex used in the image forming layer of the present invention is preferably 50% by weight or more of the total binder. The amount of the polymer latex used in the protective layer of the present invention is preferably 80% by weight or more of the total binder. In addition, polymer latex is used not only for the image forming layer and the protective layer,
It may be used for the back layer. In particular, when the heat-developable image recording material of the present invention is used for printing in which dimensional change is a problem, it is necessary to use a polymer latex. However,
The “polymer latex” referred to herein is a polymer in which a water-insoluble hydrophobic polymer is dispersed as fine particles in a water-soluble dispersion medium. The dispersion state is such that the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or has a partially hydrophilic structure in the polymer molecule and the molecular chain itself is molecularly dispersed. Any of them may be used. The average particle size of the dispersed particles is preferably in the range of 1 to 50,000 nm, more preferably about 5 to 1000 nm. There is no particular limitation on the particle size distribution of the dispersed particle size, and either a material having a wide particle size distribution or a material having a monodispersed particle size distribution may be used.
For polymer latex, see "Synthetic Resin Emulsion (edited by Tadashi Okuda and Hiroshi Inagaki, published by Kobunshi Kankokai (197
8))), "Polymer Latex Chemistry (Souichi Muroi, Published by The Society of Polymer Publishing (1970))" and the like.

The polymer Tg (glass transition temperature) of the polymer latex used for the binder of the present invention has a protective layer,
The preferred range differs between the back layer and the image forming layer. In the image forming layer, the temperature is preferably 40 ° C. or lower, more preferably −30 ° C. to 40 ° C., in order to promote diffusion of the photographically useful material during thermal development. When it is used for the protective layer or the back layer, the temperature is preferably 25 to 70 ° C. in order to come into contact with various devices.

The polymer latex of the present invention has an MFT (minimum film forming temperature) of -30 to 90 ° C., more preferably 0 to 7 ° C.
About 0 ° C. is preferable. A film forming aid may be added to control MFT. The film-forming assistant is also called a plasticizer and is an organic compound (usually an organic solvent) which lowers the MFT of the polymer latex. For example, the above-mentioned "Polymer Latex Chemistry (Souichi Muroi, published by Polymer Publishing Association (1970))" It is described in.

The polymer used in the polymer latex of the present invention includes acrylic resins, vinyl acetate resins, polyester resins, polyurethane resins, rubber resins, vinyl chloride resins, vinylidene chloride resins, polyolefin resins, and copolymers thereof. There is. The polymer may be a linear polymer, a branched polymer, or a crosslinked polymer. The polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized. The molecular weight of the polymer is 5000 to 1000 in number average molecular weight
000, preferably 10,000 to 100,000. If the molecular weight is too small, the mechanical strength of the image forming layer is insufficient, and if it is too large, the film-forming property is poor, which is not preferable.

Specific examples of the polymer latex used as a binder in the image forming layer of the present invention include the following. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer, latex of styrene / butadiene / acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer Latex of methyl methacrylate / vinyl chloride / acrylic acid copolymer, latex of vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer, and the like. Such polymers are also commercially available, and the following polymers can be used. For example, examples of acrylic resins include polyester resins such as Sebian A-4635, 46683, 4601 (manufactured by Daicel Chemical Industries, Ltd.) and Nipol Lx811, 814, 821, 820, 857 (manufactured by Zeon Corporation). HYDR is a polyurethane resin such as FINETEX ES650, 611, 675, 850 (all manufactured by Dainippon Ink and Chemicals, Inc.), WD-SIZE, WMS (all manufactured by Eastman Chemical Co., Ltd.)
AN AP10, 20, 30, 40 (Dai Nippon Ink Chemical Co., Ltd.)
LACSTAR 7310K, 3307
B, 4700H, 7132C (Dai Nippon Ink Chemical Co., Ltd.), N
ipol Lx416, 410, 438C, 2507 (Zeon Corporation)
Vinyl chloride resins such as G351 and G576 (all manufactured by Nippon Zeon Co., Ltd.), and vinylidene chloride resins such as L502 and L513 (all manufactured by Asahi Kasei Corporation) and Aron D
Examples of olefin resins such as 7020, D504, and D5071 (all manufactured by Mitsui Toatsu Co., Ltd.) include Chemipearl S120 and SA100 (all manufactured by Mitsui Petrochemical Co., Ltd.). These polymers may be used alone, or may be used by blending two or more kinds as necessary.

In the image forming layer of the present invention, the ratio of the polymer derived from the polymer latex used as the total binder is 50%.
% By weight or more, more preferably 70% by weight or more.

Among the polymer latexes used as the binder of the protective layer of the present invention, the following monomers are used as raw material monomers constituting the crosslinkable core-shell type latex. Among monomers constituting the core portion or the shell portion, as monomers not containing a functional group, vinyl monomers (for example, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, allyl methacrylate, ethylene glycol dimethacrylate, etc.) Methacrylates, methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, 2
-Acrylates such as ethylhexyl acrylate and allyl acrylate, acrylamide, methacrylamide,
Amide group-containing vinyl monomers such as methylenebisacrylamide, styrenes such as styrene, 4-methylstyrene, styrenesulfonic acid, and divinylbenzene; halogenated ethylenes such as vinyl chloride and vinylidene chloride;
Vinyl esters such as vinyl acetate and vinyl propionate; and polymerizable hydrocarbons such as ethylene and butadiene).

Among the monomers constituting the core portion or the shell portion, as a monomer having a functional group, a hydroxyl group-containing vinyl monomer (eg, hydroxyethyl acrylate, hydroxyethyl methacrylate, allyl alcohol, hydroxypropyl acrylate, hydroxypropyl methacrylate, etc.) , Isocyanate group-containing vinyl monomer (for example, isocyanatoethyl acrylate, isocyanatoethyl methacrylate, etc.), 2
-An oxazolinyl group-containing vinyl monomer (for example, 2-
Vinyl-2-oxazoline, 2-isopropenyl-2-oxazoline, alkyl-substituted 2-vinyl-2-oxazoline
(E.g., 5-methyl-2-vinyl-2-oxazoline, 4,4-dimethyl-2-vinyl-2-oxazoline), N-methylol group-containing vinyl monomers (eg, N-methylol acrylamide, N-methylol methacryl) Amides),
Epoxy group-containing vinyl monomers (for example, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, etc.) are exemplified.

Specific examples of the cross-linkable core-shell type latex include (core) polystyrene (shell) ethyl methacrylate / glycidyl methacrylate copolymer, (core) polystyrene (shell) ethyl methacrylate / 2
-Isopropenyl-2-oxazoline copolymer, (core) styrene / divinylbenzene copolymer (shell)
Ethyl methacrylate / glycidyl methacrylate copolymer, (core) styrene / divinylbenzene copolymer (shell) ethyl methacrylate / N-methylolacrylamide copolymer, (core) styrene / divinylbenzene copolymer ( (Shell part) Ethyl acrylate / N-methylol acrylamide copolymer, (Core part) Styrene / divinylbenzene copolymer (Shell part) Ethyl methacrylate / 2-isopropenyl-2-oxazoline copolymer, (Core part) Styrene / divinylbenzene copolymer (shell part) butyl methacrylate / 2-isopropenyl-
2-oxazoline copolymer, (core) styrene / divinylbenzene copolymer (shell) ethyl methacrylate / butyl acrylate / 2-hydroxyethyl methacrylate copolymer, (core) styrene / divinylbenzene copolymer Combined (shell part) 2-ethylhexyl methacrylate /
2-hydroxyethyl methacrylate copolymer, (core) styrene / divinylbenzene copolymer (shell)
Methyl acrylate / glycidyl methacrylate copolymer,
(Core) Styrene / divinylbenzene copolymer (Shell) propyl acrylate / N-methylol acrylamide copolymer, (Core) Styrene / divinylbenzene copolymer (Shell) cyclohexyl acrylate / 2-
Isopropenyl-2-oxazoline copolymer, (core)
Styrene / divinylbenzene copolymer (shell) Ethyl acrylate / 4,4-dimethyl-2-vinyl-2-oxazoline copolymer, (core) styrene / methylenebisacrylamide copolymer (shell) methacrylic acid Butyl /
Hydroxyethyl methacrylate copolymer (core)
Styrene / methylenebisacrylamide copolymer (shell part) Ethyl methacrylate / butyl acrylate / 2-hydroxyethyl methacrylate copolymer, (core part) styrene / methylenebisacrylamide copolymer (shell part) ethyl methacrylate / N-methylol acrylamide copolymer, (core) styrene / ethylene glycol dimethacrylate copolymer (shell) propyl methacrylate / isocyanatoethyl acrylate copolymer,
(Core part) styrene / ethylene glycol dimethacrylate copolymer (shell part) 2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate copolymer,
(Core) 4-methylstyrene / divinylbenzene copolymer (Shell) Hexyl methacrylate / 2-vinyl-2
-Oxazoline copolymer, (core) 4-methylstyrene / divinylbenzene copolymer (shell) methyl acrylate / glycidyl methacrylate copolymer, (core)
4-methylstyrene / divinylbenzene copolymer (shell part) propyl acrylate / N-methylol acrylamide copolymer, (core part) 4-methylstyrene / divinylbenzene copolymer (shell part) cyclohexyl acrylate / 2- Isopropenyl-2-oxazoline copolymer,
(Core) 4-methylstyrene / 2-vinyl-2-oxazoline / divinylbenzene copolymer (shell) Ethyl acrylate / 4,4-dimethyl-2-vinyl-2-oxazoline copolymer.

In order to make full use of the properties of the core-shell type latex, the Tg of the core is preferably higher than the Tg of the shell. Specifically, the Tg of the core is preferably 40 ° C or higher, more preferably 50 to 150 ° C. The Tg of the shell is preferably 70 ° C or lower, more preferably -30 to 50 ° C. The weight ratio of the monomers constituting the core part and the shell part is arbitrary, but for good film-forming properties, the core part / shell part is preferably 20/80 to 80/20,
50/50 to 70/30 is more preferred.

The monomer containing a functional group can be used in the core and / or the shell, but is preferably used in the shell since the main purpose is a crosslinking reaction after film formation. The amount of the functional group-containing monomer used is preferably 0.5 to 30% by weight, more preferably 1 to 20% by weight, based on all monomers.

In the protective layer of the present invention, the ratio of the polymer derived from the polymer latex used in the entire binder is 80% by weight.
Or more, more preferably 90% by weight or more. Further, the polymer latex contains a cross-linkable core-shell type latex, and the ratio of the cross-linkable core-shell type latex (solid content) in the entire polymer latex (solid content) is preferably 40% by weight or more, more preferably 70% by weight or more.

Preferred combinations of a crosslinkable core-shell type latex and a crosslinking agent having a functional group capable of reacting with this latex, and a preferred combination of the crosslinkable core-shell type latex and a latex having a functional group capable of reacting with this latex are as follows. , For hydroxyl group, epoxy group, isocyanate group, N-methylol group, carboxyl group, hydroxyl group for isocyanate group,
For carboxyl group, N-methylol group, amino group, 2-oxazolinyl group, isocyanate group, carboxyl group, aromatic thiol group, sulfinic acid group, isocyanate group for N-methylol group, N-methylol For the group, carboxyl group, hydroxyl group and epoxy group, there are hydroxyl group, carboxyl group, N-methylol group and amino group.

As the crosslinking agent capable of undergoing a crosslinking reaction with the crosslinkable core-shell type latex, conventionally known crosslinking agents can be used. As a specific example, Rica Resin BEO-6 is used as the epoxy compound.
Examples of isocyanate compounds such as OE (manufactured by Nippon Rika Co., Ltd.) and 1,3-diglycidyloxypropane include hexamethylene diisocyanate and duranate WB40.
-80D, WX-1741 (manufactured by Asahi Chemical Industry Co., Ltd.), Bayur 3100 (Sumitomo Bayer Urethane Co., Ltd.)
Manufactured), Takenate WD725 (Takeda Pharmaceutical Co., Ltd.)
, Aquanate 100, aquanate 200 (manufactured by Nippon Polyurethane Co., Ltd.), water-dispersible polyisocyanates described in JP-A-9-160172, and the like.
3-dimethylol propylene urea, 4-methoxy-5
Carboxyl compounds such as 5-dimethyl-N, N'-dimethylolpropyleneurea such as succinic acid, pyromellitic acid, benzophenonetetracarboxylic acid and polyacrylic acid; hydroxyl compounds such as propanediol, glycerol, polyvinyl alcohol and carboxymethylcellulose Amino compounds such as ethylenediamine, diethylenetriamine, polyethyleneimine and polyvinylamine; aromatic thiol compounds such as benzenedithiol and 3,4-dimercaptotoluene; and sulfinic acid compounds such as benzenedisulfinic acid and 3,4-disis Rufinotoluene and the like.

The amount of the crosslinking agent used is preferably from 1 to 150% by weight, more preferably from 2 to 100% by weight, based on the crosslinkable core-shell type latex (solid content). The weight ratio of the crosslinkable core-shell type latex (solid content) to the latex crosslinking agent (solid content) having a functional group capable of reacting with this latex is preferably 90/10 to 10/90, and more preferably 70/30.
~ 30/70 is more preferred.

The protective layer of the present invention has a gel fraction of 40% by weight.
As described above, the content is preferably 70% by weight. In this case, the gel fraction was determined by leaving the coating film of the protective layer formed at a drying temperature of 65 ° C. under a condition of 25 ° C. and 55% RH for 12 hours, then immersing the coating film in toluene at 25 ° C. for 24 hours to remove insoluble materials. It is separated by filtration, dried under the conditions of 25 ° C. and 55% RH, and the weight of the insoluble matter is determined. Gel fraction (% by weight) = [weight of insoluble matter (g) ÷ weight of protective layer before immersion in toluene] × 100

In the binder of the present invention, polyvinyl alcohol, polyvinyl pyrrolidone, polyether, urea-formaldehyde resin, cellulose derivatives (methyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, cyanoethyl cellulose, cellulose Acetate, etc.), polyacrylamide, poly N
-If necessary, hydrophilic polymers such as alkyl-substituted acrylamide, polyacrylic acid, polymethacrylic acid, polyvinyl sulfonic acid, polyvinyl imidazole, carrageenan, pectin, amylose, starch derivatives, alginic acid, pullulan, and gelatin may be added. The amount of the hydrophilic polymer to be added is preferably 50% by weight or less of the total binder in the image forming layer, and the protective layer accounts for 2% of the total binder.
It is preferably 0% by weight or less.

Solvent (dispersion medium) for the image forming layer coating solution of the present invention
It is preferable that 60% by weight or more (100% by weight or less) of the solvent and the solvent (dispersion medium) of the protective layer coating solution of the present invention be 80% by weight or more (100% by weight or less) of water. Water-miscible organic solvents such as alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used. Specific examples of the solvent composition include the following in addition to water. Water / methanol = 90/1
0, water / methanol = 70/30, water / ethanol = 90/10,
Water / isopropanol = 90/10, water / dimethylformamide = 95/5, water / methanol / dimethylformamide = 8
0/15/5, water / methanol / dimethylformamide = 90
/ 5/5. (However, the numbers represent wt%.)

The total amount of the binder for the protective layer of the present invention is 0.1.
^{2 to} 5.0 g / m ² , more preferably 0.5 to 3.0 g / m ²
Is preferable.

The total amount of the binder for the image forming layer of the present invention is 0.2 to 30 g / m ² , more preferably 1.0 to 15 g / m ^2.
Is preferable.

The total amount of the binder for the back layer according to the present invention is 0.01 to 3 g / m ² , more preferably 0.05 to 1.5 g.
/ M ² is preferred.

A crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like may be added to each layer.

Each of these layers may be provided in two or more layers. When there are two or more image forming layers, it is preferable to use a polymer latex as a binder for all the layers. Further, the protective layer is a layer provided on the image forming layer and may be present in two or more layers.
Preferably, a polymer latex is used for the layer, especially the outermost protective layer. The back layer is a layer provided on the undercoat layer on the back surface of the support, and there may be two or more layers. However, it is preferable to use a polymer latex for at least one layer, particularly the outermost back layer.

Various supports can be used for the heat-developable image recording material of the present invention. Typical supports are polyethylene terephthalate, polyethylene naphthalate,
Such as polyester, cellulose nitrate, cellulose ester, polyvinyl acetal, and polycarbonate. Among them, biaxially stretched polyester, especially polyethylene terephthalate (PET) has strength, dimensional stability,
It is preferable from the viewpoint of chemical resistance and the like. The thickness of the support is preferably 90 to 180 μm as a base thickness excluding the undercoat layer.

The support used in the heat-developable image recording material of the present invention is intended to alleviate the internal strain remaining in the film at the time of biaxial stretching and to eliminate the heat shrinkage distortion generated during the heat development.
Polyester, particularly polyethylene terephthalate, which has been subjected to a heat treatment in a temperature range of 130 to 210 ° C. is preferably used. Such a thermal relaxation treatment may be performed at a constant temperature within the temperature range, or may be performed while increasing the temperature.

The heat treatment of the support may be performed in the form of a roll, or may be performed while transporting the support in the form of a web. In the case where the transfer is carried out in the form of a web, the transfer tension of the support during the heat treatment is preferably 7 kg / cm ² or less, particularly preferably 4.2 kg / cm ² or less. The lower limit of the transport tension at this time is not particularly limited, but is about 0.5 kg / cm ² .

Such a heat treatment is preferably carried out after a treatment for improving the adhesion of the image forming layer and the back layer to the support, for example, after providing an undercoat layer.

After the heat treatment, the support 12
The heat shrinkage by heating at 0 ° C for 30 seconds is-
0.03% to + 0.01%, lateral direction (TD) is 0 to 0.
Preferably, it is 04%.

The support may optionally be coated with an undercoat layer using SBR, vinylidene chloride, polyester, gelatin or the like as a binder. The undercoat layer may have a multi-layer structure, or may be provided on one side or both sides of the support. At least one of these undercoat layers can be a conductive layer. The general thickness of the undercoat layer is 0.01 to 5 μm
More preferably, the thickness may be 0.05-1 μm, and the thickness of the conductive layer is 0.01-1 μm, more preferably 0.03-0.8 μm.

The back layer or undercoat layer adjacent to the support of the heat-developable image recording material of the present invention preferably contains a metal oxide in order to reduce dust adhesion. Preferably, at least one of the layers (provided on both sides of the support) is a conductive layer. However, the conductive layer is preferably not the outermost back layer.

Here, the metal oxide used is disclosed in
Particularly preferred are those described in JP-A-20033 and JP-A-56-82504.

The amount of the conductive metal oxide of the present invention to be used is preferably 0.05 to ²⁰ g, more preferably 0.1 to 10 g, per m ^{2 of} the image recording material. The surface resistivity of the metal oxide-containing layer is 10 ¹² Ω or less, preferably 10 ¹¹ Ω or less in an atmosphere of 25 ° C. and 25% RH. Thereby, good antistatic properties can be obtained. The lower limit of the surface resistivity at this time is not particularly limited, but is usually about 10 ⁷ Ω.

In the present invention, a better antistatic property can be obtained by using a fluorine-containing surfactant in addition to the above metal oxide.

The preferred fluorine-containing surfactant used in the present invention has a fluoroalkyl group, a fluoroalkenyl group, or a fluoroaryl group having 4 or more (usually 15 or less) carbon atoms, and an anionic group ( Sulfonic acid (salt), sulfuric acid (salt), carboxylic acid (salt), phosphoric acid (salt)), cationic group (amine salt, ammonium salt,
Aromatic amine salts, sulfonium salts, phosphonium salts),
Surfactants having a betaine group (carboxyamine salt, carboxyammonium salt, sulfoamine salt, sulfoammonium salt, phosphoammonium salt) or a nonionic group (substituted or unsubstituted polyoxyalkylene group, polyglyceryl group or sorbitan residue) No.

These fluorine-containing surfactants are disclosed in
0722, UK Patent 1,330,356, US Patent 4,335,201
No. 4,347,308, British Patent No. 1,417,915, JP-A-55
-149938, 58-196544 and British Patent No. 1,439,402. Some of these specific examples are described below.

[0049]

Embedded image

The layer to which the fluorine-containing surfactant of the present invention is added is not particularly limited as long as it is at least one layer of the image recording material, and examples thereof include a surface protective layer, an emulsion layer, an intermediate layer, an undercoat layer, and a back layer. be able to. Among them, a preferable addition site is the surface protective layer, and either one of the image forming layer side and the back layer side may be used. However, it is more preferable that the compound is added to at least the image forming layer side surface protective layer.

When the surface protective layer is composed of two or more layers, any of the layers may be used, and the surface protective layer may be further overcoated on the surface protective layer.

The amount of the fluorinated surfactant of the present invention may be 0.0001 to 1 g per m ^{2 of the} image recording material, more preferably 0.0002 to 0.25 g, and particularly preferably 0.1 to 0.2 g. 0003-0.1 g.

The fluorinated surfactant of the present invention comprises
Species or more may be mixed.

The Beck smoothness in the present invention can be determined by the Japanese Industrial Standard (JIS) P8119 “Smoothness test method of paper and paperboard using Beck tester” and TAPPI standard method T4.
79 can be easily obtained.

The Beck smoothness of at least one of the surface having the image forming layer of the heat-developable image recording material of the present invention and the outermost surface opposite to the surface, preferably both, is 2,000 seconds or less, more preferably 10 seconds. ~ 2000 seconds.

The Beck smoothness of the surface of the outermost layer having the image forming layer of the heat-developable image recording material and the surface of the outermost layer opposite to the surface have an average particle size of fine particles called a matting agent contained in the layers on both sides. It can be controlled by variously changing the diameter and the amount of addition. The matting agent is preferably contained in the protective layer which is the outermost layer farthest from the support on the surface having the image forming layer, and is preferably contained in the back layer which is not the outermost layer on the opposite side.

In the present invention, the average particle size of the matting agent is preferably in the range of 1 to 10 μm.

In the present invention, a preferable addition amount of the matting agent is in the range of 5 to 400 mg / m ² , particularly 10 to 200 mg / m ² .

The matting agent used in the present invention may be any solid particles which do not adversely affect the photographic characteristics. Examples of inorganic matting agents include silicon dioxide, oxides of titanium and aluminum, carbonates of zinc and calcium, sulfates of barium and calcium, and silicates of calcium and aluminum. Examples include matting agents for organic polymers such as esters, polymethyl methacrylate, polystyrene or polydivinylbenzene and copolymers thereof.

In the present invention, the porous matting agent described in JP-A-3-109542, page 2, lower left column, line 8 to page 3, upper right column, line 4; JP-A-4-127142, page 3, upper right column A matting agent surface-modified with an alkali described in line 7 to page 5, lower right column, line 4, an organic polymer matting agent described in paragraphs [0005] to [0026] of JP-A-6-118542. It is more preferable to use

Further, two or more of these matting agents may be used in combination. For example, a combination of an inorganic matting agent and an organic matting agent, a combination of a porous matting agent and a non-porous matting agent, a combination of an amorphous matting agent and a spherical matting agent, mats having different average particle sizes. (For example, a matting agent having an average particle diameter of 1.5 μm or more and a matting agent having an average particle diameter of 1 μm or less described in JP-A-6-118542).

In the present invention, it is preferable that a slip agent is contained in the surface having the image forming layer and / or the outermost surface layer opposite to the surface.

The lubricant in the present invention is not particularly limited, and any compound may be used as long as it reduces the coefficient of friction of the surface of the object when it is present on the surface of the object, compared to when it is not present.

Representative examples of the slip agent used in the present invention include, for example, US Pat. No. 3,042,522 and British Patent No. 95
No. 5,061, U.S. Pat.Nos. 3,080,317, 4,004,927,
No. 4,047,958, No. 3,489,567, British Patent No. 1,143,
No. 118, etc., silicone-based slip agent, U.S. Pat.
No. 4,043, No. 2,732,305, No. 2,976,148, No. 3,2
No. 06,311, German Patent No. 1,284,295, Higher fatty acid type, alcohol type, acid amide type slip agent described in No. 1,284,294, etc., British Patent No. 1,263,722, U.S. Patent No. 3,933,516 No. Patent No. 2,588,765, No. 3,1
No. 21,060, UK Patent No. 1,198,387, etc., ester-based and ether-based slip agents, U.S. Pat.
There is a taurine-based slip agent described in 3,042,222.

Specific examples of the slip agent preferably used include Cellolsol 524 (main component carnauba wax), Polylon A, 393, H-481 (main component polyethylene wax), and Himicron G-110 (main component ethylene bisstearic acid). Amide), High Micron G-270
(Main component stearic acid amide) (all manufactured by Chukyo Yushi Co., Ltd.).

The amount of the slip agent used is 0.1 to 50% by weight, preferably 0.5 to 30% by weight, based on the amount of the binder in the added layer.

The photosensitive silver halide used in the present invention may be any of silver chloride, silver chlorobromide, and silver iodochlorobromide. The distribution of the halogen composition in the grains may be uniform, the halogen composition may be changed stepwise, or may be changed continuously.

The method of forming the photosensitive silver halide in the present invention is well known in the art, and uses, for example, the methods described in Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458. be able to. Specific methods that can be used in the present invention include a method of converting a part of the silver of the organic silver salt to a photosensitive silver halide by adding a halogen-containing compound to the prepared organic silver salt, gelatin. Alternatively, a method of preparing a photosensitive silver halide grain by adding a silver supply compound and a halogen supply compound to another polymer solution and mixing the resultant with an organic silver salt can be used. In the present invention, the latter method can be preferably used. The particle size of the photosensitive silver halide is preferably small for the purpose of suppressing the white turbidity after image formation to be low.
20 μm or less, more preferably 0.01 μm or more and 0.15 μm or less,
More preferably, it is 0.02 μm or more and 0.12 μm or less. Here, the grain size means the length of the edge of the silver halide grain when the silver halide grain is a cubic or octahedral so-called normal crystal. In the case where the silver halide grains are tabular grains, the diameter refers to a diameter when converted into a circular image having the same area as the projected area of the main surface. In the case of other than normal crystals, for example, in the case of spherical grains, rod-shaped grains, etc., it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

The shape of the silver halide grains is cubic,
Octahedral, tabular particles, spherical particles, rod-like particles, potato-like particles and the like can be mentioned. In the present invention, cubic particles and tabular particles are particularly preferable. When tabular silver halide grains are used, the average aspect ratio is preferably 100: 1 to 2: 1, more preferably 50: 1 to 3: 1. Further, grains having rounded corners of silver halide grains can also be preferably used. The surface index (mirror index) of the outer surface of the photosensitive silver halide grain is not particularly limited, but the spectral sensitization efficiency when the spectral sensitizing dye is adsorbed is high.
The proportion occupied by the {100} plane is preferably high. The ratio is preferably 50% or more, more preferably 65% or more,
80% or more is more preferable. The Miller index {100} plane ratio was determined by T. Tani; J. Imaging Sci., 29, 165 (1985), which utilizes the adsorption dependence of {111} and {100} planes on sensitizing dye adsorption. It can be determined by the method described.

The light-sensitive silver halide grains of the present invention can be prepared from Group VII or VIII (Groups 7 to 10) of the periodic table.
Of a metal or metal complex. Rhodium, rhenium, ruthenium, osnium and iridium are preferably the metals of Group VII or VIII of the periodic table or the central metal of the metal complex. One type of these metal complexes may be used, or two or more types of complexes of the same metal and different metals may be used in combination. The preferable content is in the range of 1 nmol to 10 mmol, and more preferably in the range of 10 nmol to 100 µmol per 1 mol of silver. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used.

As the rhodium compound used in the present invention, a water-soluble rhodium compound can be used. For example, rhodium (III) halide compounds or rhodium complex salts having a ligand such as halogen, amines, oxalato, etc., for example, hexachlororhodium (III) complex salt, pentachloroacolodium (III) complex salt, tetrachlorodiaco Rhodium (III) complex salt, hexabromorhodium (III) complex salt, hexaamminerhodium (III) complex salt,
And trisalatrodium (III) complex salts. These rhodium compounds are used by dissolving them in water or a suitable solvent. A method generally used to stabilize a solution of the rhodium compound, that is, a hydrogen halide aqueous solution (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) Etc.) or alkali halides (eg, KCl, NaCl, KB
r, NaBr, etc.) can be used. Instead of using water-soluble rhodium, it is also possible to add and dissolve other silver halide grains doped with rhodium during the preparation of silver halide.

The addition amount of these rhodium compounds is preferably in the range of 1 × 10 ⁻⁸ mol to 5 × 10 ⁻⁶ mol per mol of silver halide, and particularly preferably in the range of 5 × 10 ⁻⁸ mol to 1 × 10 mol.
10 ^-6 mol.

These compounds can be appropriately added at the time of production of silver halide emulsion grains and at each stage before coating the emulsion.
It is preferably incorporated into silver halide grains.

The rhenium, ruthenium,
Osminium is disclosed in JP-A-63-2042, JP-A-1-285941,
It is added in the form of a water-soluble complex salt described in JP-A Nos. 2-20852 and 2-20855. Particularly preferred is a six-coordinate complex represented by the following formula. [ML ₆ ] ⁿ -where M represents Ru, Re, or Os, L represents a ligand, and n represents 0, 1, 2, 3, or 4. In this case, the counter ion is not important and ammonium or alkali metal ions are used.

Preferred ligands include halide ligands, cyanide ligands, cyanide ligands, nitrosyl ligands, thionitrosyl ligands and the like.
Examples of specific complexes used in the present invention are shown below, but the present invention is not limited thereto.

[ReCl ₆ ] ^3- [ReBr ₆ ] ^3- [ReCl ₅ (NO)] ^2- [Re (NS) Br ₅ ] ^2- [Re (NO) (CN) ₅ ] ^2- [Re (O ) ₂ (CN) ₄ ] ^3- [RuCl ₆ ] ^3- [RuCl ₄ (H ₂ O) ₂ ] ^- [RuCl ₅ (H ₂ O)] ^2- [RuCl ₅ (NO)] ^2- [RuBr ₅ ( NS)] ^2- [Ru (CO) ₃ Cl ₃ ] ^2- [Ru (CO) Cl ₅ ] ^2- [Ru (CO) Br ₅ ] ^2- [OsCl ₆ ] ^3- [OsCl ₅ (NO)] ^{2 -} [Os (NO) (CN) ₅ ] ^2- [Os (NS) Br ₅ ] ^2- [Os (O) ₂ (CN) ₄ ] ^4-

The addition amount of these compounds is 1
It is preferably in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻⁵ mol per mol, particularly preferably 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁶ mol.

These compounds can be appropriately added at the time of production of silver halide emulsion grains and at each stage before coating the emulsion.
It is preferably incorporated into silver halide grains.

In order to add these compounds into silver halide grains by adding them during silver halide grain formation, a metal complex powder or an aqueous solution dissolved together with NaCl and KCl is added to the aqueous solution during grain formation. Salt or a water-soluble halide solution, or as a third solution when the silver salt and the halide solution are mixed at the same time.
A method of preparing silver halide grains by a liquid simultaneous mixing method,
Alternatively, there is a method in which a required amount of an aqueous solution of a metal complex is charged into a reaction vessel during the formation of particles. Especially powder or Na
A method in which an aqueous solution dissolved together with Cl and KCl is added to a water-soluble halide solution is preferable.

For addition to the particle surface, a required amount of an aqueous solution of a metal complex can be charged into the reaction vessel immediately after the formation of the particles, during or during physical ripening, or at the time of chemical ripening.

As the iridium compound used in the present invention, various compounds can be used. Examples thereof include hexachloroiridium, hexaammineiridium, trioxalatoiridium, hexacyanoiridium, and pentachloronitrosyliridium. These iridium compounds are used after being dissolved in water or a suitable solvent. However, a method generally used for stabilizing a solution of the iridium compound, that is, an aqueous solution of hydrogen halide (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) is used. Etc.) or alkali halides (eg, KCl, NaCl, KBr, NaB
r) can be used. Instead of using water-soluble iridium, it is also possible to add and dissolve another iridium-doped silver halide grain during silver halide preparation.

Further, the silver halide grains used in the present invention include cobalt, iron, nickel, chromium, palladium,
It may contain metal atoms such as platinum, gold, thallium, copper and lead. For compounds of cobalt, iron, chromium, and ruthenium, hexacyano metal complexes can be preferably used. Specific examples include ferricyanate ion, ferrocyanate ion, hexacyanocobaltate ion,
Examples include, but are not limited to, hexacyanochromate ions and hexacyanoruthenate ions. The metal complex in the silver halide may be contained uniformly, may be contained in the core portion at a high concentration, or may be contained in the shell portion at a high concentration, and there is no particular limitation.

1 × 1 per mole of the above metal silver halide
0 ^-9 to 1 × 10 ^-4 mol is preferred. Further, in order to contain the above-mentioned metal, a metal salt in the form of a single salt, a double salt or a complex salt can be added at the time of preparing particles.

The photosensitive silver halide grains can be desalted by washing with a method known in the art such as a noodle method or a flocculation method, but in the present invention, it may or may not be desalted. .

The silver halide emulsion of the present invention is preferably subjected to chemical sensitization. As the method of chemical sensitization, known methods such as a sulfur sensitization method, a selenium sensitization method, a tellurium sensitization method, and a noble metal sensitization method can be used, and these are used alone or in combination. When used in combination,
For example, sulfur sensitization and gold sensitization, sulfur sensitization and selenium sensitization and gold sensitization, sulfur sensitization and tellurium sensitization and gold sensitization, and sulfur sensitization and selenium sensitization Method, tellurium sensitization method, gold sensitization method and the like are preferable.

The sulfur sensitization used in the present invention is usually carried out by adding a sulfur sensitizer and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. As the sulfur sensitizer, known compounds can be used.For example, in addition to the sulfur compound contained in gelatin, various sulfur compounds such as thiosulfates, thioureas, thiazoles, and rhodanines are used. be able to. Preferred sulfur compounds are thiosulfates and thiourea compounds. The amount of the sulfur sensitizer to be added varies under various conditions such as pH during chemical ripening, temperature, and the size of silver halide grains, but is preferably from 10 ^-7 to 10 ^-2 mol per mol of silver halide. Yes, more preferably 1
0 ^-5 to 10 ^-3 mol.

As the selenium sensitizer used in the present invention, known selenium compounds can be used. That is, it is usually carried out by adding an unstable and / or non-unstable selenium compound and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. As unstable selenium compounds, JP-B-44-15748, JP-B-43-13489, JP-A-4-25832
And the compounds described in JP-A Nos. 4-109240 and 4-324855 can be used. In particular, it is preferable to use the compounds represented by formulas (VIII) and (IX) in JP-A-4-324855.

The tellurium sensitizer used in the present invention is a compound which forms silver telluride which is presumed to be a sensitizing nucleus on the surface or inside of silver halide grains. The formation rate of silver telluride in a silver halide emulsion is described in JP-A-5-3132.
It can be tested by the method described in No. 84. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides, bis (carbamoyl) tellurides, diacyl tellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, P = Te Compounds having a bond, tellurocarboxylates, Te-organyltellurocarboxylates, di (poly) tellurides, tellurides, tellurols, telluroacetals,
Tellurosulfonates, compounds having a P-Te bond, containing T
e Heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Specifically, U.S. Patent Nos. 1,623,499 and 3,320,069,
No. 3,772,031, UK Patent No. 235,211 and No. 1,121,49
No. 6, No. 1,295,462, No. 1,396,696, Canadian Patent No. 800,958, JP-A-4-204640, Japanese Patent Application No. 3-53693,
3-131598, 4-129787, Journal of Chemical Society Chemical Communication (J. Chem. Soc. Chem. Commun.) 635 (1980), ibid 1102
(1979), ibid 645 (1979), Journal of Chemical Society Parkin Transaction (J. Chem. Soc. Perkin. Trans.) 1, 2191 (1980), S.M. The chemistry of organic selenium and tellurium compound (S. Patai) ed. (The Chemistry of Organic Serenium and Tellunium)
Compounds, Vol. 1 (1986) and the compounds described in Vol. 2 (1987) can be used. Particularly, compounds represented by formulas (II), (III) and (IV) in JP-A-5-313284 are preferred.

The amount of the selenium and tellurium sensitizers used in the present invention varies depending on the silver halide grains to be used, the conditions of chemical ripening, etc., but is generally 10 ^-8 to 10 ^-2 mol per mol of silver halide. Preferably, about 10 ^-7 to 10 ^-3 mol is used. The conditions for chemical sensitization in the present invention are not particularly limited, but the pH is 5 to 8, the pAg is 6 to 11, preferably 7 to 10, and the temperature is 40 to 95 ° C, preferably 45 to 45 ° C. 85 ° C.

The noble metal sensitizer used in the present invention includes gold, platinum, palladium, iridium and the like, and gold sensitization is particularly preferable. Specific examples of the gold sensitizer used in the present invention include chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, and gold sulfide, and 10 ^-7 to 10 ^-2 mol per mol of silver halide. Degrees can be used.

In the silver halide emulsion used in the present invention, a cadmium salt, a sulfite, a lead salt, a thallium salt and the like may coexist in the process of forming silver halide grains or physical ripening.

In the present invention, reduction sensitization can be used. As specific compounds of the reduction sensitization method, in addition to ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like can be used. . Also, when the pH of the emulsion is 7 or more or p
Reduction sensitization can be achieved by aging while keeping Ag at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ion during grain formation.

A thiosulfonic acid compound may be added to the silver halide emulsion of the present invention according to the method described in EP 293,917.

The heat-developable image recording material used in the present invention may contain only one silver halide emulsion or two or more silver halide emulsions (for example, those having different average grain sizes, different halogen compositions, different crystal habits). And those having different conditions of chemical sensitization).

The amount of the photosensitive silver halide used in the present invention is preferably 0.01 mol to 0.5 mol, more preferably 0.02 mol to 0.3 mol, and more preferably 0.03 mol to 1 mol of the organic silver salt. It is particularly preferably at least 0.25 mol and not more than 0.25 mol. Regarding the mixing method and the mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide particles and organic silver salt are mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. There is a method of mixing, or a method of preparing an organic silver salt by mixing photosensitive silver halide prepared at any timing during the preparation of the organic silver salt,
There is no particular limitation as long as the effects of the present invention are sufficiently exhibited.

As the silver halide preparation method of the present invention, a so-called halation method in which a part of silver of an organic silver salt is halogenated with an organic or inorganic halide is also preferably used. As the organic halide used here, any compound may be used as long as it is a compound which reacts with an organic silver salt to generate a silver halide.N-halogenoimide (e.g., N-bromosuccinimide) and quaternary nitrogen halide (e.g. Tetrabutylammonium bromide, etc.), an association of a quaternary nitrogen halide and a halogen molecule (pyridinium perbromide), and the like. As the inorganic halogen compound, any compound may be used as long as it reacts with an organic silver salt to generate silver halide.
(Sodium chloride, lithium bromide, potassium iodide, ammonium bromide, etc.), alkaline earth metal halides (calcium bromide, magnesium chloride, etc.), transition metal halides (ferric chloride, cupric bromide, etc.) ), A metal complex having a halogen ligand (such as sodium bromide iridate and ammonium rhodate), a halogen molecule (bromine, chlorine,
Iodine). Further, a desired organic / inorganic halide may be used in combination.

In the present invention, the halide is added in an amount of preferably from 1 to 500 mmol, more preferably from 10 to 250 mmol, as a halogen atom, per mol of the organic silver salt.
mmol is more preferred.

The organic silver salt that can be used in the present invention is
Relatively stable to light, but forms a silver image when heated to 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent It is a silver salt. The organic silver salt can be any organic substance including a source capable of reducing silver ions. Silver salts of organic acids, in particular silver salts of long-chain fatty carboxylic acids (with 10 to 30, preferably 15 to 28 carbon atoms) are preferred. Complexes of organic or inorganic silver salts wherein the ligand has a complex stability constant in the range of 4.0 to 10.0 are also preferred. The silver donor is preferably present in about 5-70 of the imaging layer.
% By weight. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the aliphatic carboxylic acid silver salt include silver behenate, silver arachidate, silver stearate, silver oleate,
Silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate, silver fumarate, silver tartrate, silver linoleate, silver butyrate and silver camphorate, and mixtures thereof.

Silver salts of compounds containing a mercapto group or a thione group and derivatives thereof can also be used.
Preferred examples of these compounds include 3-mercapto-4
-Phenyl-1,2,4-triazole silver salt, 2-mercaptobenzimidazole silver salt, 2-mercapto-5-aminothiadiazole silver salt, 2- (ethylglycolamide) benzothiazole silver salt, S- Silver salts of thioglycolic acid such as silver salts of alkylthioglycolic acid (where the alkyl group has 12 to 22 carbon atoms), silver salts of dithiocarboxylic acids such as silver salts of dithioacetic acid, silver salts of thioamides, 5 -Carboxyl-1-methyl-2-phenyl-4-thiopyridine silver salt, mercaptotriazine silver salt, 2-mercaptobenzoxazole silver salt, silver salts described in U.S. Pat.No.4,123,274, for example, 3-amino-5 Silver salts of 1,2,4-mercaptothiazole derivatives such as -benzylthio-1,2,4-thiazole silver salt, 3- (3-carboxyethyl) -4- described in U.S. Pat.No. 3,301,678
Includes silver salts of thione compounds such as silver salt of methyl-4-thiazoline-2-thione. Furthermore, compounds containing an imino group can also be used. Preferred examples of these compounds include silver salts of benzotriazole and derivatives thereof,
For example, silver salts of benzotriazole such as silver methylbenzotriazole, silver salts of halogen-substituted benzotriazole such as silver 5-chlorobenzotriazole, U.S. Pat.
0,709 1,2,4-triazole or 1-H-
Includes silver salts of tetrazole, silver salts of imidazole and imidazole derivatives, and the like. For example, U.S. Pat.
Various silver acetylide compounds as described in No. 1 and 4,775,613 can also be used.

The shape of the organic silver salt that can be used in the present invention is not particularly limited, but a needle crystal having a short axis and a long axis is preferable. In the present invention, the minor axis is 0.01 μm or more and 0.2 μm or more.
0 μm or less, major axis of 0.10 μm or more and 5.0 μm or less, minor axis of 0.01 μm or more and 0.15 μm or less, and major axis of 0.10 μm or more and 4.0 μm or less are more preferred. The particle size distribution of the organic silver salt is preferably monodispersed. Monodisperse and the minor axis, the percentage of the value obtained by dividing the standard deviation of the length of each major axis by each minor axis, major axis is preferably 100% or less, more preferably 80% or less,
More preferably, it is 50% or less. The shape of the organic silver salt can be measured from a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring the monodispersity, there is a method of obtaining the standard deviation of the volume-weighted average diameter of the organic silver salt, the percentage of the value divided by the volume-weighted average diameter (coefficient of variation) is preferably 100% or less, more Preferably 80% or less,
More preferably, it is 50% or less. As a measuring method, for example, the particle size (volume weighted average diameter) obtained by irradiating a laser beam to an organic silver salt dispersed in a liquid and obtaining an autocorrelation function with respect to a time change of fluctuation of the scattered light is obtained. Can be.

The organic silver salt that can be used in the present invention includes:
Preferably, desalting can be performed. The method for desalting is not particularly limited, and a known method can be used. However, a known filtration method such as centrifugal filtration, suction filtration, ultrafiltration, or floc-forming water washing by a coagulation method can be preferably used.

The organic silver salt which can be used in the present invention is a method of preparing a solid fine particle dispersion using a dispersant in order to obtain fine particles having a small particle size and without aggregation. The method of dispersing the organic silver salt into solid fine particles is carried out by using a known fine means (for example, ball mill, vibrating ball mill, planetary ball mill, sand mill, colloid mill, jet mill, roller mill, high-pressure homogenizer) in the presence of a dispersing aid. Used and can be mechanically dispersed.

When the organic silver salt is formed into solid fine particles using a dispersant, for example, polyacrylic acid, a copolymer of acrylic acid, a maleic acid copolymer, a maleic acid monoester copolymer, and acryloylmethyl Synthetic anionic polymers such as propane sulfonic acid copolymer, semi-synthetic anionic polymers such as carboxymethyl starch and carboxymethyl cellulose, anionic polymers such as alginic acid and pectic acid, JP-A-52-92716, WO88 / 04794, etc. Anionic surfactant described, the compound described in Japanese Patent Application No. 7-350753, or known anionic, nonionic,
Cationic surfactants and other known polymers such as polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, hydroxypropylcellulose, and hydroxypropylmethylcellulose, or naturally occurring polymer compounds such as gelatin can be appropriately selected and used. .

It is a general method that the dispersing aid is mixed with the organic silver salt powder or the organic silver salt in a wet cake state before the dispersion, and then sent as a slurry to the dispersing machine. Heat treatment or treatment with a solvent may be performed in the combined state to obtain an organic silver salt powder or a wet cake. The pH may be controlled by a suitable pH adjuster before, during or after dispersion.

Instead of mechanically dispersing, fine particles may be formed by coarsely dispersing in a solvent by controlling the pH and then changing the pH in the presence of a dispersing aid. At this time, an organic solvent may be used as a solvent used for the coarse dispersion, and the organic solvent is usually removed after the completion of the fine particle formation.

The prepared dispersion is stored with stirring for the purpose of suppressing sedimentation of fine particles during storage, or stored in a highly viscous state (for example, in a jelly state using gelatin) with a hydrophilic colloid. You can also do.
Further, a preservative can be added for the purpose of preventing the propagation of various bacteria during storage.

Although the organic silver salt of the present invention can be used in a desired amount, the silver amount is preferably 0.1 to 5 g / m ² , more preferably 1 to 3 g, expressed in terms of 1 m ^{2 of} the heat-developable image recording material. /
a m ^2.

The heat-developable image recording material of the present invention preferably contains a reducing agent for an organic silver salt. Reducing agents for organic silver salts are any substance that reduces silver ions to metallic silver,
Preferably, it may be an organic substance. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred.
The reducing agent is used in an amount of 5 to 1 mol of silver on the surface having the image forming layer.
It is preferably contained in 50% (mol), and 10 to 40% (mol)
More preferably, it is included. The layer to which the reducing agent is added may be any layer on the side having the image forming layer. When it is added to a layer other than the image forming layer, it is preferable to use a relatively large amount of 10 to 50% (mol) with respect to 1 mol of silver. Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material utilizing an organic silver salt, a wide range of reducing agents are disclosed in JP-A-46-6074 and JP-A-47-1238.
47-33621, 49-46427, 49-115540, 50-14
No. 334, No. 50-36110, No. 50-147711, No. 51-32632,
No. 51-1023721, No. 51-32324, No. 51-51933, No. 52-8
4727, 55-108654, 56-146133, 57-82828
No. 57-82829, JP-A-6-3793, U.S. Pat.
No. 86, No. 3,679,426, No. 3,751,252, No. 3,751,255
Nos. 3,761,270, 3,782,949, 3,839,048,
3,928,686, 5,464,738, German patent 2321328,
It is disclosed in European Patent No. 692732 and the like. For example, phenylamide oxime, 2-thienylamide oxime and
Amide oximes such as p-phenoxyphenylamide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; such as the combination of 2,2-bis (hydroxymethyl) propionyl-β-phenylhydrazine and ascorbic acid A combination of an aliphatic carboxylic acid aryl hydrazide and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (for example, hydroquinone and bis (ethoxyethyl) hydroxylamine, piperidinohexose reductone or Such as a combination of formyl-4-methylphenylhydrazine); phenylhydroxamic acid, p
Hydroxamic acids such as -hydroxyphenylhydroxamic acid and β-alinine hydroxamic acid; combinations of azines with sulfonamidophenols (eg, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol, etc.); ethyl-α-cyano Α-cyanophenylacetic acid derivatives such as 2-methylphenylacetate and ethyl-α-cyanophenylacetate; 2,2-dihydroxy-1,1-binaphthyl, 6,6-dibromo-2,2-dihydroxy-1,1 Bis-β-naphthol as exemplified by -binaphthyl and bis (2-hydroxy-1-naphthyl) methane; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (for example, 2,4-dihydroxybenzophenone or 2 , 4-dihydroxyacetophenone); 5-pyrazolone, such as 3-methyl-1-phenyl-5-pyrazolone; dimethylaminohexose Reductones as exemplified by ductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone; sulfones such as 2,6-dichloro-4-benzenesulfonamidophenol and p-benzenesulfonamidophenol Amidophenol reducing agents; 2-phenylindan-1,3-dione and the like; chromans such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman; 2,6-dimethoxy-3,5-dicarbethoxy 1,4-dihydropyridines such as -1,4-dihydropyridine; bisphenols (for example, bis (2-hydroxy-3-t-
Butyl-5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4,4-ethylidene-bis (2-t-butyl-6-methylphenol), 1,1- Bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane and the like; ascorbic acid derivatives (for example,
And aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indan-1,3-diones; chromanol (such as tocopherol). Particularly preferred reducing agents are bisphenol and chromanol.

The reducing agent of the present invention may be added by any method such as a solution, a powder, and a solid fine particle dispersion. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

When an additive known as a “toning agent” for improving image quality is included, the optical density may increase. The toning agent may also be advantageous in forming a black silver image. The toning agent is preferably contained in an amount of 0.1 to 50% (mole) per mole of silver on the surface having the image forming layer, and more preferably 0.5 to 20% (mole).
Further, the toning agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material using an organic silver salt, a wide range of color toning agents are disclosed in JP-A-46-6077 and JP-A-47-10282.
Nos. 49-5019, 49-5020, 49-91215, 49-9
No. 1215, No. 50-2524, No. 50-32927, No. 50-67132,
No. 50-67641, No. 50-114217, No. 51-3223, No. 51-279
No. 23, No. 52-14788, No. 52-99813, No. 53-1020, No. 5
3-76020, 54-156524, 54-156525, 61-1836
No. 42, JP-A-4-56848, JP-B-49-10727, 54-2033
No. 3, U.S. Pat.Nos. 3,080,254, 3,446,648, 3,782,9
No. 41, No. 4,123,282, No. 4,510,236, British Patent 138079
No. 5, Belgian Patent No. 841910 and the like. Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazolin-5-one and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinedione Cyclic imides such as; naphthalimides (eg, N
-Hydroxy-1,8-naphthalimide); cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-
Mercapto-1,2,4-triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole Illustrative mercaptans; N- (aminomethyl) aryldicarboximides, such as (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl)-
Naphthalene-2,3-dicarboximide); and blocked pyrazoles, isothiuronium derivatives and certain photobleaching agents (eg, N, N′-hexamethylenebis (1-carbamoyl-3,5-dimethylpyrazole), 1 , 8- (3,6-diazaoctane) bis (isothiuronium trifluoroacetate) and 2-tribromomethylsulfonyl)-(benzothiazole)); and 3-ethyl-5 [(3-ethyl-2-benzothia) Zolinylidene) -1-methylethylidene] -2-thio-2,4-oxazolidinedione; phthalazinone, phthalazinone derivative or metal salt, or 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7- Derivatives such as dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione; phthalazinone and phthalic acid derivatives such as phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachloro Combination of anhydride such as phthalic acid); phthalazine, phthalazine derivatives or metal salts or 4- (1-naphthyl)
Derivatives such as phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachloro Quinazolinedione, benzoxazine or naphthoxazine derivatives; rhodium complexes, such as hexachlororhodium, that function not only as color tone regulators but also in-situ as sources of halide ions for silver halide formation (III) ammonium, rhodium bromide, rhodium nitrate and hexachlororhodium (II
I) potassium acid and the like; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide;
Benzoxazine-2,4 such as benzoxazine-2,4-dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione -Diones; pyrimidines and asymmetric-triazines (eg, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (eg, 3,6-dimercapto-1,4 -Diphenyl-1
H, 4H-2,3a, 5,6a-tetraazapentalene, and 1,4-di
(o-chlorophenyl) -3,6-dimercapto-1H, 4H-2,3a, 5,6
a-tetraazapentalene).

The color-toning agent of the present invention may be added by any method such as a solution, a powder and a dispersion of solid fine particles. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

In order to obtain a high-contrast image, the heat-developable image recording material of the present invention preferably contains a super-high contrast agent (nucleating agent) in the image forming layer and / or the layer adjacent thereto. The super-high contrast agent used in the present invention includes a substituted alkene derivative represented by the formula (1), a substituted isoxazole derivative represented by the formula (2), a specific acetal compound represented by the formula (3), And hydrazine derivatives are preferably used.

The substituted alkene derivative represented by the formula (1), the substituted isoxazole derivative represented by the formula (2), and the specific acetal compound represented by the formula (3) used in the present invention will be described.

[0116]

Embedded image

In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure. In the formula (2), R ⁴ represents a substituent. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic group. Represents an oxy group, a heterocyclic thio group, or a heterocyclic amino group. In the formula (3), X and Y or A and B may be bonded to each other to form a cyclic structure.

The compound represented by the formula (1) will be described in detail.

In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure.

When R ¹ , R ² , and R ³ represent a substituent, examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group (an aralkyl group, An alkyl group, an active methine group, etc.), an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (including an N-substituted nitrogen-containing heterocyclic group), and a heterocyclic group containing a quaternized nitrogen atom ( For example, a pyridinio group), an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a carboxy group or a salt thereof, an imino group, an imino group substituted with an N atom, a thiocarbonyl group, a sulfonylcarbamoyl group, an acylcarbamoyl group, Famoylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group, cyano group, thiocarbamoyl group, A droxy group or a salt thereof, an alkoxy group (including a group repeatedly containing an ethyleneoxy group or a propyleneoxy group unit), an aryloxy group, a heterocyclic oxy group, an acyloxy group, an (alkoxy or aryloxy) carbonyloxy group, and a carbamoyloxy group , Sulfonyloxy group, amino group, (alkyl, aryl, or heterocycle) amino group, acylamino group, sulfonamide group, ureido group, thioureido group, imide group, (alkoxy or aryloxy)
Carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, 4
Grade ammonium, oxamoylamino, (alkyl or aryl) sulfonyluureido, acylureido, acylsulfamoylamino, nitro, mercapto, (alkyl, aryl, or heterocycle)
Thio group, acylthio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or a salt thereof, sulfamoyl group, acylsulfamoyl group, sulfonylsulfamoyl group or a salt thereof, phosphoryl group, phosphorus Examples thereof include a group having an acid amide or phosphate structure, a silyl group and a stannyl group.

These substituents may be further substituted with these substituents.

The electron-withdrawing group represented by Z in the formula (1) is a substituent whose Hammett's substituent constant σp can take a positive value, specifically, a cyano group, an alkoxycarbonyl Group, aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted with an N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, halogen atom,
A perfluoroalkyl group, a perfluoroalkaneamide group, a sulfonamide group, an acyl group, a formyl group, a phosphoryl group, a carboxy group (or a salt thereof), a sulfo group (or a salt thereof), a heterocyclic group, an alkenyl group, an alkynyl group, Examples include an acyloxy group, an acylthio group, a sulfonyloxy group, and an aryl group substituted with these electron-withdrawing groups. Here, the heterocyclic group is a saturated or unsaturated heterocyclic group, for example, a pyridyl group, a quinolyl group,
Examples thereof include a pyrazinyl group, a quinoxalinyl group, a benzotriazolyl group, an imidazolyl group, a benzimidazolyl group, a hydantoin-1-yl group, a succinimide group, and a phthalimide group.

The electron-withdrawing group represented by Z in the formula (1) may further have a substituent. As the substituent, R ¹ , R ² , and R ^{3 in the} formula (1) may be substituted. The same substituents as the substituents that may be present when representing the substituents are exemplified.

In the formula (1), R ¹ and Z, R ² and R ³ , R ¹
And R ² , or R ³ and Z may be bonded to each other to form a cyclic structure. The cyclic structure formed at this time is a non-aromatic carbon ring or a non-aromatic hetero ring. is there.

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

The silyl group represented by Z in the formula (1) is preferably a trimethylsilyl group, a t-butyldimethylsilyl group, a phenyldimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, a trimethylsilyldimethylsilyl group. And so on.

The electron-withdrawing group represented by Z in the formula (1) is preferably a group having a total number of carbon atoms of 0 to 30, that is, a cyano group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, Carbonyl group,
Imino group, imino group substituted with N atom, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group, acyloxy group, acylthio group, or any electron withdrawing And a phenyl group substituted with a functional group, more preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, an imino group, a sulfamoyl group,
An alkylsulfonyl group, an arylsulfonyl group, an acyl group, a formyl group, a phosphoryl group, a trifluoromethyl group, or a phenyl group substituted with any electron-withdrawing group, and particularly preferably a cyano group, a formyl group, an acyl group. , An alkoxycarbonyl group, an imino group or a carbamoyl group.

The group represented by Z in the formula (1) is more preferably an electron-withdrawing group.

In the formula (1), the substituent represented by R ¹ , R ² and R ³ is preferably a group having a total carbon number of 0 to 30, specifically, Z in the above formula (1). Groups having the same meanings as the electron-withdrawing groups represented, and alkyl and hydroxy groups
(Or its salt), mercapto group (or its salt), alkoxy group, aryloxy group, heterocyclic oxy group, alkylthio group, arylthio group, heterocyclic thio group, amino group, alkylamino group, arylamino group, heterocyclic Examples include an amino group, a ureido group, an acylamino group, a sulfonamide group, and a substituted or unsubstituted aryl group.

Furthermore, in the formula (1), R ¹ is preferably an electron-withdrawing group, an aryl group, an alkylthio group, an alkoxy group, an acylamino group, a hydrogen atom or a silyl group.

When R ¹ represents an electron-withdrawing group, the following groups having preferably 0 to 30 carbon atoms in total, ie, a cyano group, a nitro group, an acyl group, a formyl group, an alkoxycarbonyl group,
An aryloxycarbonyl group, a thiocarbonyl group, an imino group, an imino group substituted with an N atom, an alkylsulfonyl group, an arylsulfonyl group, a carbamoyl group, a sulfamoyl group, a trifluoromethyl group, a phosphoryl group, a carboxy group (or a salt thereof), Or a saturated or unsaturated heterocyclic group, and a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, a carbamoyl group, an imino group, an imino group substituted with an N atom, a sulfamoyl group, a carboxy group (or a salt thereof) Or a saturated or unsaturated heterocyclic group. Particularly preferred are a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, and a saturated or unsaturated heterocyclic group.

When R ¹ represents an aryl group, it is preferably a substituted or unsubstituted phenyl group having 6 to 30 carbon atoms in total, and examples of the substituent include arbitrary substituents.
Among them, an electron-withdrawing substituent is preferable.

In the formula (1), R ¹ is more preferably an electron-withdrawing group or an aryl group.

In the formula (1), the substituents represented by R ² and R ³ are preferably, specifically, groups having the same meaning as the electron-withdrawing group represented by Z in the above-mentioned formula (1), and alkyl groups. , A hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, an amino group, an alkylamino group, an anilino group, Examples include a heterocyclic amino group, an acylamino group, and a substituted or unsubstituted phenyl group.

In formula (1), R ² and R ³ are more preferably when one of them is a hydrogen atom and the other is a substituent. Preferably as the substituent, an alkyl group, a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, an amino group Group, an alkylamino group, an anilino group, a heterocyclic amino group, an acylamino group (particularly a perfluoroalkaneamide group), a sulfonamide group, a substituted or unsubstituted phenyl group, or a heterocyclic group,
More preferably a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group, Preferably a hydroxy group (or a salt thereof), an alkoxy group,
Or a heterocyclic group.

In the formula (1), it is also preferable that Z and R ¹ , or R ² and R ³ form a cyclic structure.
The cyclic structure formed in this case is a non-aromatic carbon ring or a non-aromatic hetero ring, preferably 5 to 7 members.
Having a total carbon number of 1 to 4 including substituents.
0, more preferably 3 to 30.

[0137] Among the compounds represented by formula (1), more One of preferred, Z is a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, an imino group or a carbamoyl group,, R ¹ is Represents an electron-withdrawing group or an aryl group, and one of R ^{2 and} R ³ is a hydrogen atom;
The other is a compound representing a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group. . Furthermore, one of the particularly preferable compounds represented by the formula (1) is that Z and R ^{1 form a} non-aromatic 5- to 7-membered cyclic structure, and R ² or R ³ Is one of a hydrogen atom, the other is a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, Or a compound representing a heterocyclic group. At this time, Z which forms a non-aromatic cyclic structure together with R ¹ is preferably an acyl group, a carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group and the like, and R ¹ is an acyl group, a carbamoyl group ,
Preferred are an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted with an N atom, an acylamino group, a carbonylthio group and the like.

Next, the compound represented by the formula (2) will be described.

In the formula (2), R ⁴ represents a substituent. R ⁴
Examples of the substituent represented by are the same as those described for the substituents of R ^{1 to} R ^{3 in} the formula (1).

The substituent represented by R ⁴ is preferably an electron-withdrawing group or an aryl group. When R ⁴ represents an electron-withdrawing group, preferably the following groups having a total carbon number of 0 to 30,
That is, a cyano group, a nitro group, an acyl group, a formyl group, an alkoxycarbonyl group, an aryloxycarbonyl group,
Alkylsulfonyl group, arylsulfonyl group, carbamoyl group, sulfamoyl group, trifluoromethyl group,
A phosphoryl group, an imino group, or a saturated or unsaturated heterocyclic group, and a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, and a heterocyclic group. preferable. Particularly preferably, a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group,
It is a carbamoyl group or a heterocyclic group.

When R ⁴ represents an aryl group, it is preferably a substituted or unsubstituted phenyl group having a total of 0 to 30 carbon atoms, and the substituent is represented by R ¹ , R ² , R ³ of the formula (1). When represents a substituent, the same as those described as the substituent can be mentioned.

R ⁴ is particularly preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, a heterocyclic group, or a substituted or unsubstituted phenyl group, and most preferably a cyano group, a heterocyclic group, or an alkoxycarbonyl group. is there.

Next, the compound represented by the formula (3) will be described in detail.

In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group. ,
Represents a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group. X and Y or A and B may be bonded to each other to form a cyclic structure.

As the substituents represented by X and Y in the formula (3), the same as those described for the substituents R ^{1 to} R ^{3 in} the formula (1) can be mentioned. Specifically, alkyl groups (including perfluoroalkyl groups, trichloromethyl groups, etc.), aryl groups, heterocyclic groups, halogen atoms, cyano groups, nitro groups, alkenyl groups, alkynyl groups, acyl groups, formyl groups, alkoxy groups Carbonyl group, aryloxycarbonyl group, imino group, imino group substituted with an N atom, carbamoyl group, thiocarbonyl group, acyloxy group, acylthio group, acylamino group, alkylsulfonyl group, arylsulfonyl group, sulfamoyl group, phosphoryl group, carboxy Group (or its salt), sulfo group (or its salt), hydroxy group (or its salt), mercapto group (or its salt), alkoxy group, aryloxy group, heterocyclic oxy group, alkylthio group, arylthio group, hetero group Ring thio group, amino group, alkylami Group, anilino group, heterocyclic amino group, a silyl group, and the like.

These groups may further have a substituent. X and Y may be bonded to each other to form a cyclic structure, and the cyclic structure formed in this case may be a non-aromatic carbon ring or a non-aromatic hetero ring. .

The substituents represented by X and Y in the formula (3) are preferably groups having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and include a cyano group, an alkoxycarbonyl group, Aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted with N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group , An acylamino group, an acyloxy group, an acylthio group, a heterocyclic group, an alkylthio group, an alkoxy group, or an aryl group.

In the formula (3), X and Y are more preferably a cyano group, a nitro group, an alkoxycarbonyl group, a carbamoyl group, an acyl group, a formyl group, an acylthio group, an acylamino group, a thiocarbonyl group, a sulfamoyl group,
An alkylsulfonyl group, an arylsulfonyl group, an imino group, an imino group substituted with an N atom, a phosphoryl group, a trifluoromethyl group, a heterocyclic group, or a substituted phenyl group, and particularly preferably a cyano group or an alkoxycarbonyl group , A carbamoyl group, an alkylsulfonyl group,
An arylsulfonyl group, an acyl group, an acylthio group, an acylamino group, a thiocarbonyl group, a formyl group, an imino group, an imino group substituted with an N atom, a heterocyclic group, or a phenyl group substituted with any electron-withdrawing group; is there.

It is also preferable that X and Y combine with each other to form a non-aromatic carbon ring or a non-aromatic hetero ring. At this time, the formed cyclic structure is preferably a 5- to 7-membered ring, and has a total carbon number of 1 to 40, and more preferably 3 to 7 members.
30 is preferred. X and Y forming a cyclic structure include an acyl group, a carbamoyl group, an oxycarbonyl group,
Preferred are a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted with an N atom, an acylamino group, a carbonylthio group and the like.

In the formula (3), A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group,
Represents a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group, which may be bonded to each other to form a cyclic structure. The group represented by A or B in the formula (3) is preferably a group having a total carbon number of 1 to 40, more preferably a group having a total carbon number of 1 to 30, and may further have a substituent.

In the formula (3), A and B more preferably combine with each other to form a cyclic structure. The cyclic structure formed at this time is preferably a 5- to 7-membered non-aromatic hetero ring, and preferably has a total carbon number of 1 to 40, and more preferably 3 to 30. In this case, an example in which A and B are linked (-AB-) is, for example, -O- (C
_{H 2) 2 -O -, -} O- (CH 2) 3 -O -, - S- (CH
_{2) 2 -S -, - S-} (CH 2) 3 -S -, - S-ph-S
_{-, - N (CH 3)} - (CH 2) 2 -O -, - N (CH 3)
_{- (CH 2) 2 -S -} , - O- (CH 2) 2 -S -, - O-
_{(CH 2) 3 -S -,} - N (CH 3) -ph-O -, - N
(CH ₃ ) -ph-S-, -N (ph)-(CH ₂ ) _2-
S- and so on.

The compounds represented by the formulas (1) to (3) of the present invention may have incorporated therein an adsorptive group that adsorbs to silver halide. Examples of such adsorbing groups include U.S. Pat. Nos. 4,385,108 and 4,459,347 such as alkylthio, arylthio, thiourea, thioamide, mercapto heterocyclic, and triazole groups.
JP-A-59-195233 and JP-A-59-200231.
Nos. 59-201045 and 59-201046
Nos. 59-201047 and 59-201048
No. 59-201049, JP-A-61-17073.
Nos. 3, 61-270744, 62-948, 63-234244, 63-234245, and 6
The group described in 3-234246 is mentioned. These adsorbing groups to silver halide may be precursors. Examples of such a precursor include groups described in JP-A-2-285344.

The compounds represented by the formulas (1) to (3) of the present invention may be those in which a ballast group or a polymer commonly used in immobile photographic additives such as couplers is incorporated. Good. Particularly, those incorporating a ballast group are one of preferred examples of the present invention. The ballast group is a group having a carbon number of 8 or more and relatively inactive to photographic properties, such as an alkyl group, an aralkyl group,
It can be selected from an alkoxy group, a phenyl group, an alkylphenyl group, a phenoxy group, an alkylphenoxy group and the like. Examples of the polymer include, for example,
No. 00530.

The compounds represented by the formulas (1) to (3) of the present invention contain a cationic group (specifically, a group containing a quaternary ammonium group, or a quaternized nitrogen). A nitrogen-containing heterocyclic group containing an atom), a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, an (alkyl, aryl, or heterocyclic) thio group, or a dissociable group (carboxy group, Sulfo group,
Acylsulfamoyl group, carbamoylsulfamoyl group, etc.). In particular, a group containing a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, or a group containing an (alkyl, aryl, or heterocyclic) thio group is one of preferred examples of the present invention. Specific examples of these groups include, for example, JP-A-7-2
No. 34471, JP-A-5-333466, JP-A-6-633
19032, JP-A-6-19031, JP-A-5-4
No. 5761, U.S. Pat. No. 4,994,365, U.S. Pat.
88604, JP-A-3-259240, JP-A-7-
No. 5610, JP-A-7-244348, German Patent 40
06032 and the like.

Next, specific examples of the compounds represented by formulas (1) to (3) of the present invention are shown below. However, the present invention is not limited to the following compounds.

[0156]

Embedded image

[0157]

Embedded image

[0158]

Embedded image

[0159]

Embedded image

[0160]

Embedded image

[0161]

Embedded image

[0162]

Embedded image

[0163]

Embedded image

[0164]

Embedded image

The compounds represented by the formulas (1) to (3) of the present invention can be prepared from water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol) and ketones (acetone, methyl ethyl ketone). ), Dimethylformamide, dimethylsulfoxide,
It can be used by dissolving it in methyl cellosolve or the like.

Further, by a well-known emulsification and dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate or an auxiliary solvent such as ethyl acetate or cyclohexanone is used for dissolution, An emulsified dispersion can be prepared and used. Alternatively, a compound powder can be dispersed in a suitable solvent such as water by a ball mill, a colloid mill, or ultrasonic waves by a method known as a solid dispersion method and used.

The compounds represented by the formulas (1) to (3) of the present invention can be added to the layer on the image forming layer side with respect to the support, that is, the image forming layer or any layer on this layer side. However, it is preferable to add it to the image forming layer or a layer adjacent thereto.

The amount of the compounds represented by the formulas (1) to (3) of the present invention is preferably 1 × 10 ⁻⁶ to 1 mol per 1 mol of silver, and 1 × 10 ^{−5 to} 5 × 10 5 ^-1 mol is more preferred, and 2 × 10 ^-5 to 2 × 10 ^-1 mol is most preferred.

The compounds represented by the formulas (1) to (3) can be easily synthesized by known methods. For example, US Pat. No. 5,545,515 and US Pat.
No. 9, U.S. Pat. No. 5,654,130, International Patent WO-97
/ 34196, or Japanese Patent Application No. 9-354107.
The compounds can be synthesized with reference to the methods described in Japanese Patent Application Nos. 9-309813 and 9-272002.

The compounds represented by formulas (1) to (3) of the present invention may be used alone or in combination of two or more. Also, in addition to the above, US Pat.
No. 5,635,339, U.S. Pat.
0, International Patent WO-97 / 34196, U.S. Pat.
No. 686228;
No. 279962, Japanese Patent Application No. 9-228881, Japanese Patent Application No. 9-273935, Japanese Patent Application No. 9-354107, Japanese Patent Application No. 9-309813, Japanese Patent Application No. 9-296174, Japanese Patent Application No. 9-282564. No., Japanese Patent Application No. 9-272002,
Compounds described in Japanese Patent Application Nos. 9-272003 and 9-332388 may be used in combination. Furthermore, it can be used in combination with a hydrazine derivative as described below.

The hydrazine derivative used as a super-high contrast agent in the present invention is preferably a compound represented by the following formula (H).

[0172]

Embedded image

In the formula, R ¹² represents an aliphatic group, an aromatic group, or a heterocyclic group, R ¹¹ represents a hydrogen atom or a block group, and G ¹ represents —CO—, —COCO—, —C (= S)-, -SO _2- , -SO-, -PO
(R ^{1 3)} - group (. R ¹³ is selected from the same range as the groups defined in R ^11, may be different from R ^11), or an iminomethylene group. A ¹ and A ^{2 each} represent a hydrogen atom, or one of them represents a hydrogen atom and the other represents a substituted or unsubstituted alkylsulfonyl group, a substituted or unsubstituted arylsulfonyl group, or a substituted or unsubstituted acyl group. m1 is 0 or 1, when m1 is 0, R ¹¹ represents an aliphatic group, an aromatic group or a heterocyclic group.

In the formula (H), the aliphatic group represented by R ¹² is preferably a substituted or unsubstituted, linear, branched or cyclic alkyl, alkenyl or alkynyl group having 1 to 30 carbon atoms.

In the formula (H), the aromatic group represented by R ¹² is a monocyclic or condensed-ring aryl group such as a phenyl group and a naphthyl group. The heterocyclic group represented by R ¹² is a monocyclic or condensed, saturated or unsaturated, aromatic or non-aromatic heterocyclic group, and the heterocyclic ring in these groups is, for example, a pyridine ring , Pyrimidine ring, imidazole ring, pyrazole ring, quinoline ring, isoquinoline ring, benzimidazole ring, thiazole ring, benzothiazole ring, piperidine ring, triazine ring, morpholino ring, piperidine ring, piperazine ring and the like.

Preferred as R ¹² is an aryl group or an alkyl group.

R ¹² may be substituted. Representative examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), an alkyl group (an aralkyl group, a cycloalkyl group, and an active methine group). Group, etc.), an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, a heterocyclic group containing a quaternized nitrogen atom (eg, a pyridinio group), an acyl group, an alkoxycarbonyl group,
Aryloxycarbonyl group, carbamoyl group, carboxy group or a salt thereof, sulfonylcarbamoyl group, acylcarbamoyl group, sulfamoylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group, cyano group, thiocarbamoyl group, hydroxy group, alkoxy group ( (Including a group repeatedly containing an ethyleneoxy group or a propyleneoxy group unit), an aryloxy group, a heterocyclic oxy group, an acyloxy group, an (alkoxy or aryloxy) carbonyloxy group, a carbamoyloxy group, a sulfonyloxy group, an amino group, (Alkyl, aryl, or heterocycle) amino group, N-substituted nitrogen-containing heterocyclic group, acylamino group, sulfonamide group, ureido group, thioureido group, imide group, (alkoxy or aryloxy) Ruboniruamino group, a sulfamoylamino group, semicarbazide group, thiosemicarbazide group,
Hydrazino group, quaternary ammonium group, oxamoylamino group, (alkyl or aryl) sulfonyluureido group, acylureido group, acylsulfamoylamino group, nitro group, mercapto group, (alkyl, aryl,
Or heterocycle) thio group, (alkyl or aryl)
A sulfonyl group, an (alkyl or aryl) sulfinyl group, a sulfo group or a salt thereof, a sulfamoyl group, an acylsulfamoyl group, a sulfonylsulfamoyl group or a salt thereof, a group having a phosphoric amide or a phosphoric ester structure, and the like. Can be

These substituents may be further substituted with these substituents.

[0179] Preferred examples of the substituent which may be R ¹² optionally has, when R ¹² represents an aromatic group or a heterocyclic group, (including an active methylene group) alkyl group, an aralkyl group, a heterocyclic group, Substituted amino group, acylamino group, sulfonamide group, ureido group, sulfamoylamino group,
Imide group, thioureido group, phosphoric amide group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, carboxy group (including its salt), (alkyl , Aryl, or heterocycle)
Examples thereof include a thio group, a sulfo group (including a salt thereof), a sulfamoyl group, a halogen atom, a cyano group, and a nitro group.

When R ¹² represents an aliphatic group, an alkyl group, an aryl group, a heterocyclic group, an amino group, an acylamino group, a sulfonamide group, a ureido group, a sulfamoylamino group, an imide group, a thioureido group, Phosphoric acid amide group, hydroxy group, alkoxy group, aryloxy group,
Acyloxy group, acyl group, alkoxycarbonyl group,
Aryloxycarbonyl group, carbamoyl group, carboxy group (including its salt), (alkyl, aryl or heterocycle) thio group, sulfo group (including its salt), sulfamoyl group, halogen atom, cyano group, nitro group, etc. Is preferred.

In the formula (H), R ¹¹ represents a hydrogen atom or a block group, and the block group is specifically an aliphatic group (specifically, an alkyl group, an alkenyl group, an alkynyl group) or an aromatic group. (Monocyclic or condensed-ring aryl group),
Represents a heterocyclic group, an alkoxy group, an aryloxy group, an amino group or a hydrazino group.

The alkyl group represented by R ¹¹ is preferably a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, such as methyl, ethyl, trifluoromethyl, difluoromethyl, 2-carboxytetra. Fluoroethyl group, pyridiniomethyl group, difluoromethoxymethyl group, difluorocarboxymethyl group, 3-hydroxypropyl group, 3-methanesulfonamidopropyl group, phenylsulfonylmethyl group, o-hydroxybenzyl group, methoxymethyl group, phenoxymethyl group, Examples thereof include a 4-ethylphenoxymethyl group, a phenylthiomethyl group, a t-butyl group, a dicyanomethyl group, a diphenylmethyl group, a triphenylmethyl group, a methoxycarbonyldiphenylmethyl group, a cyanodiphenylmethyl group, and a methylthiodiphenylmethyl group. The alkenyl group is preferably an alkenyl group having 1 to 10 carbon atoms, for example, a vinyl group, a 2-ethoxycarbonylvinyl group, a 2-trifluoro-2.
-Methoxycarbonylvinyl group and the like. The alkynyl group is preferably an alkynyl group having 1 to 10 carbon atoms, such as an ethynyl group and a 2-methoxycarbonylethynyl group. As the aryl group, a monocyclic or condensed-ring aryl group is preferable, and an aryl group containing a benzene ring is particularly preferable. For example, phenyl, perfluorophenyl, 3,5-dichlorophenyl, 2-methanesulfonamidophenyl, 2-carbamoylphenyl, 4,5-
Dicyanophenyl group, 2-hydroxymethylphenyl group,
Examples thereof include a 2,6-dichloro-4-cyanophenyl group and a 2-chloro-5-octylsulfamoylphenyl group.

The heterocyclic group is preferably at least
5- to 6-membered, saturated or unsaturated, monocyclic or fused-ring heterocyclic group containing one nitrogen, oxygen, and sulfur atom, such as morpholino group, piperidino group (N-substituted), imidazolyl group, indazolyl Groups (such as 4-nitroindazolyl group), pyrazolyl group, triazolyl group, benzimidazolyl group, tetrazolyl group, pyridyl group, pyridinio group (such as N-methyl-3-pyridinio group), quinolinio group, and quinolyl group.

As the alkoxy group, an alkoxy group having 1 to 8 carbon atoms is preferable, and examples thereof include a methoxy group, a 2-hydroxyethoxy group, a benzyloxy group and a t-butoxy group. As the aryloxy group, a substituted or unsubstituted phenoxy group is preferable, and as the amino group, an unsubstituted amino group, and an alkylamino group having 1 to 10 carbon atoms, an arylamino group, or a saturated or unsaturated heterocyclic amino group ( (Including a nitrogen-containing heterocyclic amino group containing a quaternized nitrogen atom). Examples of amino groups include 2,2,6,6
-Tetramethylpiperidin-4-ylamino group, propylamino group, 2-hydroxyethylamino group, anilino group, o
-Hydroxyanilino group, 5-benzotriazolylamino group, N-benzyl-3-pyridinioamino group and the like. As the hydrazino group, a substituted or unsubstituted hydrazino group, or a substituted or unsubstituted phenylhydrazino group (such as a 4-benzenesulfonamidophenylhydrazino group) is particularly preferred.

The group represented by R ¹¹ may be substituted, and examples of the substituent include those exemplified as the substituent of R ¹² .

[0186] R ¹¹ in formula (H) is such that rise to cyclization disrupts portion of G ¹ -R ¹¹ from the remainder molecule to generate a cyclic structure containing a -G ¹ -R ¹¹ moiety of atoms And examples thereof include, for example, those described in JP-A-63-29751.

The hydrazine derivative represented by the formula (H) is
An adsorptive group that adsorbs to silver halide may be incorporated. Examples of such adsorptive groups include U.S. Pat.
Nos. 85,108, 4,459,347, JP-A-59-195233, and 5
9-200231, 59-201045, 59-201046, 59-201
No. 047, No. 59-201048, No. 59-201049, JP-A-61-1707
No. 33, No. 61-270744, No. 62-948, No. 63-234244, No.
63-234245 and 63-234246. These adsorbing groups to silver halide may be precursors. Examples of such a precursor include groups described in JP-A-2-285344.

R ¹¹ or R ^{12 in} the formula (H) may have a ballast group or polymer commonly used in immobile photographic additives such as couplers incorporated therein. Ballast group is a group having a carbon number of 8 or more, is relatively inert to photographic properties, for example, an alkyl group, an aralkyl group, an alkoxy group, a phenyl group, an alkylphenyl group, a phenoxy group, an alkylphenoxy group, and the like. You can choose from. Examples of the polymer include those described in JP-A-1-100530.

R ¹¹ or R ¹² in the formula (H) may contain a plurality of hydrazino groups as substituents. At this time, the compound represented by the formula (H) represents a polymer with respect to the hydrazino group. Specifically, for example, JP-A-64-86134, JP-A-4-16938, JP-A-5-97091, WO95-32452, WO95-
No. 32453, Japanese Patent Application No. 7-351132, Japanese Patent Application No. 7-351269, Japanese Patent Application No. 7-351168, Japanese Patent Application No. 7-351287, and the compounds described in Japanese Patent Application No. 7-351279. Can be

In formula (H), R ¹¹ or R ¹² is a cationic group (specifically, a group containing a quaternary ammonium group, or a nitrogen-containing heterocyclic ring containing a quaternized nitrogen atom). Group), a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group, an (alkyl, aryl, or heterocycle) thio group, or a dissociable group (carboxy group, sulfo group, acylsulfamoyl) dissociable by a base A carbamoylsulfamoyl group). Examples of these groups include, for example, JP-A-7-234471, JP-A-5-333466, JP-A-6-19032
No., JP-A-6-19301, JP-A-5-45761, U.S. Pat.
No. 4,365, U.S. Pat.No.4,988,604, JP-A-3-259240, JP-A-7-5610, JP-A-7-244348, German Patent 4,006,032
And the like.

In the formula (H), A ¹ and A ² represent a hydrogen atom, an alkyl or arylsulfonyl group having 20 or less carbon atoms (preferably a phenylsulfonyl group or a sum of substituent constants of Hammett is -0.5 or more) Phenylsulfonyl group), an acyl group having 20 or less carbon atoms (preferably a benzoyl group, or a Hammett's substituent constant sum is -0.1.
A benzoyl group substituted to be 5 or more, or a linear, branched, or cyclic substituted or unsubstituted aliphatic acyl group (here, substituents include, for example, a halogen atom, an ether group, a sulfonamide group, Amide group, hydroxy group, carboxy group, sulfo group, etc.)).

A ¹ and A ² are most preferably hydrogen atoms.

Next, particularly preferred hydrazine derivatives in the present invention will be described.

R ¹² is preferably a phenyl group or a substituted alkyl group having 1 to 3 carbon atoms.

When R ¹² represents a phenyl group, preferred substituents thereof are a nitro group, an alkoxy group, an alkyl group, an acylamino group, a ureido group, a sulfonamide group,
Thioureido group, carbamoyl group, sulfamoyl group,
Examples include a carboxy group (or a salt thereof), a sulfo group (or a salt thereof), an alkoxycarbonyl group, or a chloro atom.

When R ¹² represents a substituted phenyl group, the substituent may be, directly or via a linking group, a ballast group, an adsorptive group to silver halide, a group containing a quaternary ammonium group, or a quaternized group. A nitrogen-containing heterocyclic group containing a nitrogen atom, a group containing a repeating unit of an ethyleneoxy group, (alkyl, aryl,
Or heterocycle) to form a thio group, nitro group, alkoxy group, acylamino group, sulfonamide group, dissociative group (carboxy group, sulfo group, acylsulfamoyl group, carbamoylsulfamoyl group, etc.) or a multimer More preferably, at least one of the resulting hydrazino groups (the group represented by -NHNH-G ¹ -R ¹¹ ) is substituted.

[0197] When R ¹² represents a substituted alkyl group having 1 to 3 carbon atoms, R ¹² is more preferably a substituted methyl group, more preferably a disubstituted methyl group or trisubstituted methyl group, as a substituent Are specifically a methyl group, a phenyl group, a cyano group, an (alkyl, aryl or heterocycle) thio group, an alkoxy group, an aryloxy group, a chloro atom, a heterocyclic group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl A group, a sulfamoyl group, an amino group, an acylamino group, or a sulfonamide group is preferred, and a substituted or unsubstituted phenyl group is particularly preferred.

When R ¹² represents a substituted methyl group, more preferred specific examples are t-butyl, dicyanomethyl, dicyanophenylmethyl, triphenylmethyl (trityl), diphenylmethyl, methoxycarbonyldiphenyl Examples include a methyl group, a cyanodiphenylmethyl group, a methylthiodiphenylmethyl group, a cyclopropyldiphenylmethyl group, and among them, a trityl group is most preferred.

In the formula (H), R ¹² is most preferably a substituted phenyl group.

In the formula (H), m1 represents 1 or 0,
When m1 is 0, R ¹¹ represents an aliphatic group, an aromatic group or a heterocyclic group. When m1 is 0, R ¹¹ is particularly preferably a substituted alkyl group of the phenyl group or 1 to 3 carbon atoms, which is the same as the preferable ranges of R ¹² described above.

M1 is preferably 1.

Among the groups represented by R ¹¹ , preferred are a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group and an aryl group when R ¹² represents a phenyl group and G ¹ is a —CO— group. Or a heterocyclic group, more preferably a hydrogen atom, an alkyl group, or an aryl group, and most preferably a hydrogen atom or an alkyl group. Where R
^{When 1} represents an alkyl group, the substituent is particularly preferably a halogen atom, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, or a carboxy group.

R ¹² represents a substituted methyl group, and G ¹ represents —CO—
In the case of a group, R ¹¹ is preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkoxy group, an amino group.
(Unsubstituted amino group, alkylamino group, arylamino group, heterocyclic amino group), more preferably a hydrogen atom, alkyl group, aryl group, heterocyclic group, alkoxy group, alkylamino group, arylamino group, hetero It is a ring amino group. When G ¹ is a —COCO— group, regardless of R ¹² , R ¹¹ is preferably an alkoxy group, an aryloxy group, or an amino group, particularly a substituted amino group, specifically an alkylamino group, an arylamino group, or a saturated amino group. Alternatively, an unsaturated heterocyclic amino group is preferable.

When G ¹ is a —SO ₂ — group, R ¹¹ is preferably an alkyl group, an aryl group or a substituted amino group, regardless of R ¹² .

In the formula (H), G ¹ is preferably a —CO— group or a —COCO— group, particularly preferably a —CO— group.

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

[0207]

[Table 1]

[0208]

[Table 2]

[0209]

[Table 3]

[0210]

[Table 4]

[0211]

[Table 5]

[0212]

[Table 6]

[0213]

[Table 7]

[0214]

[Table 8]

[0215]

[Table 9]

[0216]

[Table 10]

[0219]

[Table 11]

[0218]

[Table 12]

[0219]

[Table 13]

[0220]

[Table 14]

[0221]

[Table 15]

[0222]

[Table 16]

[0223]

[Table 17]

[0224]

[Table 18]

[0225]

[Table 19]

[0226]

[Table 20]

[0227]

[Table 21]

[0228]

[Table 22]

The hydrazine derivatives represented by the formula (H) may be used alone or in combination of two or more.

As the hydrazine derivative used in the present invention, in addition to the above, the following hydrazine derivatives are preferably used. (In some cases, they can be used in combination.) The hydrazine derivative used in the present invention can also be obtained by various methods described in the following patents.
Can be synthesized.

Compounds represented by (Chemical Formula 1) described in JP-B-6-77138, specifically, compounds described on pages 3 and 4 of the same publication. Compounds represented by formula (I) described in JP-B-6-93082, specifically, compounds 1 to 38 described on pages 8 to 18 of the publication. Compounds represented by the general formulas (4), (5) and (6) described in JP-A-6-230497, specifically the compound 4- described on pages 25 and 26 of the same publication. 1 to compound 4-1
0, compounds 5-1 to 5-42 on pages 28 to 36, and page 39,
Compounds 6-1 to 6-7 described on page 40. Compounds represented by formulas (1) and (2) described in JP-A-6-289520, specifically, compound 1-1 described on pages 5 to 7 of the same publication)
~ 1-17) and 2-1). JP-A-6-313936 describes the
Compounds represented by 2) and (Formula 3), specifically, the compounds described on pages 6 to 19 of the same publication. A compound represented by (Chemical Formula 1) described in JP-A-6-313951, specifically from page 3 to
Compounds described on page 5. A compound represented by the general formula (I) described in JP-A-7-5610, specifically, from page 5 to 10
Compounds I-1 to I-38 described on page. A compound represented by the general formula (II) described in JP-A-7-77783;
Compounds II-1 to II-102 described on pages 10 to 27. JP 7-1044A
Compounds represented by formulas (H) and (Ha) described in No. 26, specifically, compounds H-1 to H-44 described on pages 8 to 15 of the same publication. A compound described in JP-A-9-22082, which is characterized by having an anionic group or a nonionic group forming an intramolecular hydrogen bond with a hydrogen atom of hydrazine in the vicinity of a hydrazine group. , A compound represented by the general formula (B), the general formula (C), the general formula (D), the general formula (E), or the general formula (F), specifically, the compound N-1 described in the same publication ~ N-30. Compounds represented by the general formula (1) described in JP-A-9-22082, specifically, compounds D-1 to D-55 described in the same publication.

Further, “Known Techniques (1 to
207) ”(published by Aztec) on pages 25 to 34. Compounds D-2 and D-39 of JP-A-62-86354 (pages 6 to 7).

The hydrazine derivative of the present invention can be prepared by using a suitable organic solvent such as alcohols (methanol, ethanol,
Propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide,
It can be used by dissolving it in dimethyl sulfoxide, methyl cellosolve or the like.

Further, by a well-known emulsification and dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate or an auxiliary solvent such as ethyl acetate or cyclohexanone is used for dissolution, An emulsified dispersion can be prepared and used. Alternatively, a powder of a hydrazine derivative can be dispersed in water by a ball mill, a colloid mill, or an ultrasonic wave by a method known as a solid dispersion method and used.

The hydrazine derivative of the present invention may be added to the layer on the image forming layer side with respect to the support, that is, to the image forming layer or any other layer on the layer side. Preferably, it is added to the layer.

The amount of the hydrazine derivative of the present invention to be added is as follows.
1 × 10 ⁻⁶ to 1 × 10 ⁻² mol is preferable per 1 mol, and 1 × 10 ⁻⁵
55 × 10 ^-3 mol is more preferable, and 2 × 10 ^{-5 to} 5 × 10 ^-3 mol is most preferable.

Further, the present invention provides a method for forming a super-high contrast image.
A high contrast accelerator can be used in combination with the above-mentioned super-high contrast agent. For example, the amine compounds described in U.S. Patent No. 5,545,505, specifically AM-1 to AM-5, and 5,545,507
, Specifically HA-1 to HA
Acrylonitriles described in JP-A-5,545,507, specifically CN-1 to CN-13, hydrazine compounds described in JP-A-5,558,983, specifically CA-1 to CA-6, JP-A-9-2973
Onium salts described in No. 68, specifically A-1 to A-4
2, B-1 to B-27, C-1 to C-14 and the like can be used.

The synthesis method, addition method, addition amount and the like of the above-mentioned super-high contrast agent and high-contrast accelerator can be carried out as described in each of the cited patents.

As the sensitizing dye in the present invention, any dye can be used as long as it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holopolar cyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye, and the like can be used. Useful sensitizing dyes for use in the present invention include, for example, RESEARCH DISCLOSURE Item 17
Item 643IV-A (p.23, December 1978), Item 1831X (August 1979)
p.437) or in the literature cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers, scanners, imagesetters and plate making cameras can be advantageously selected.

As an example of spectral sensitization to red light, He-Ne
For lasers, so-called red light sources such as red semiconductor lasers and LEDs, I-1 to I-1 described in JP-A-54-18726.
-38, the compound of I-1 to I-35 described in JP-A-6-75322 and the compound of I-1 to I-34 described in JP-A-7-287338, JP-B-55-39818 Dyes 1 to 20 described, compounds of I-1 to I-37 described in JP-A-62-284343 and compounds of I-1 to I-34 described in JP-A-7-287338 are advantageously selected. Is done.

For a semiconductor laser light source in the wavelength range of 750 to 1400 nm, various known dyes including cyanine, merocyanine, styryl, hemicyanine, oxonol, hemioxonol and xanthene dyes are spectrally advantageously sensitized. Can be done. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nuclei, oxazoline nuclei, pyrroline nuclei, pyridine nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei and imidazole nuclei. Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus. Including. Among the above cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Patent 3,761,279,
3,719,495 and 3,877,943, British Patent 1,466,201
No. 1,469,117, No. 1,422,057, Tokuhei 3-10391
No. 6-52387, JP-A-5-341432, 6-94781,
It may be appropriately selected from known dyes as described in JP-A-6-301141.

Particularly preferred as the structure of the dye used in the present invention is a cyanine dye having a thioether bond-containing substituent (for example, see JP-A-62-58239 and JP-A-3-13863).
No.8, No.3-138642, No.4-255840, No.5-72659, No.5-
72661, 6-222491, 2-230506, 6-258757
No., 6-317868, 6-324425, Tokuyohei 7-500926,
Dyes described in U.S. Pat.No. 5,541,054), dyes having a carboxylic acid group (for example, JP-A-3-163440, 6-30114
No. 1, U.S. Pat.No. 5,441,899), merocyanine dyes, polynuclear merocyanine dyes and polynuclear cyanine dyes
(JP 47-6329, JP 49-105524, JP 51-127719, JP
52-80829, 54-61517, 59-214846, 60-6750
No., 63-159841, JP-A-6-35109, 6-59381,
Nos. 7-146537, 7-46537, JP-T-55-50111, British Patent 1,467,638, and US Pat. No. 5,281,515).

Further, dyes described in Example 5 of US Pat. Nos. 5,510,236 and 3,871,887 as dyes forming a J-band,
JP-A-2-96131 and JP-A-59-48753 are disclosed and can be preferably used in the present invention.

These sensitizing dyes may be used alone.
Two or more kinds may be used in combination. Combinations of sensitizing dyes are often used, especially for supersensitization. Along with the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are
Research Disclosure Volume 176, 17643 (December 1978) No. 23
Section IV of Page IV, or JP-B-49-25500, 43-43933,
These are described in JP-A-59-19032 and JP-A-59-192242.

The sensitizing dyes used in the present invention may be used in combination of two or more. To add sensitizing dyes to a silver halide emulsion, they may be directly dispersed in the emulsion,
Or water, methanol, ethanol, propanol,
Acetone, methyl cellosolve, 2,2,3,3-tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol , N, N-dimethylformamide or the like, alone or in a mixed solvent, and added to the emulsion.

As disclosed in US Pat. No. 3,469,987, a dye is dissolved in a volatile organic solvent, and this solution is dispersed in water or a hydrophilic colloid. Method of adding to Japanese Patent Publication No. 44-23389,
As disclosed in JP-A-44-27555 and JP-A-57-22091, a dye is dissolved in an acid and this solution is added to the emulsion, or an acid or base is added to the emulsion as an aqueous solution in the presence of an acid or base. A method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to an emulsion as disclosed in U.S. Patent Nos. 3,822,135 and 4,006,025, JP-A-51-746, a method in which a dye is directly dispersed in a hydrophilic colloid and the dispersion is added to an emulsion as disclosed in JP-A-51-746.
As disclosed in JP-A No. 24, a method of dissolving a dye using a compound that causes a red shift and adding this solution to an emulsion can also be used. Also, ultrasonic waves can be used for dissolution.

The sensitizing dye used in the present invention may be added to the silver halide emulsion of the present invention at any time during the preparation of the emulsion which has been found to be useful. For example, U.S. Patents 2,735,766 and 3,628,960,
4,183,756, 4,225,666, JP-A-58-184142,
As disclosed in the specification of JP-A-60-196749 and the like, the timing before silver halide grain forming step and / or desalting, during and / or after desalting and before the start of chemical ripening. As disclosed in the specification such as JP-A-58-113920, any time immediately before chemical ripening or during the process, after chemical ripening, and before coating the emulsion before coating It may be added at the time and in the process.
Further, as disclosed in the specification of U.S. Pat. No. 4,225,666, JP-A-58-7629, etc., the same compound may be used alone or in combination with a compound having a different structure, for example, during the particle forming step. The compound may be divided and added during the ripening step or after the completion of the chemical ripening, or may be added separately before or during the chemical ripening or after the completion of the chemical ripening. May be added.

The amount of the sensitizing dye used in the present invention may be a desired amount in accordance with the performance such as sensitivity and fog.
1 per mole of silver halide in the photosensitive layer as the image forming layer
It is preferably from 0 ^-6 to 1 mol, more preferably from 10 ^-4 to 10 ^-1 mol.

The silver halide emulsion according to the invention or /
And the organic silver salts can be further protected against the formation of additional fog by antifoggants, stabilizers and stabilizer precursors, and can be stabilized against reduced sensitivity during storage in inventory. Suitable antifoggants, stabilizers and stabilizer precursors that can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716; U.S. Pat.Nos. 2,886,437 and 2,444,605. Azaindene, U.S. Pat.
8,663 mercury salt, U.S. Pat.No. 3,287,135 urazole, U.S. Pat.No. 3,235,652 sulfocatechol, British Patent 623,448 Oxime,
Nitrone, nitroindazole, U.S. Patent No. 2,839,405
No. 3,220,839, thiuronium salts, and U.S. Pat.Nos. 2,566,263 and 2,597,915, palladium, platinum and gold salts, U.S. Pat.Nos. 4,108,665 and 4,442,202 No. 4,128,557
Nos. 4,137,079 and 4,138,365 and 4,
No. 4,59,350 and U.S. Pat.
And the phosphorus compounds described in No. 1,985.

The antifoggant preferably used in the present invention is an organic halide, for example, as described in JP-A-50-119624.
No. 50-120328, No. 51-121332, No. 54-58022, No.
56-70543, 56-99335, 59-90842, 61-12964
No. 2, 62-129845, JP-A-6-208191, 7-5621,
Nos. 7-2781, 8-15809, U.S. Pat.
Compounds such as those disclosed in US Pat.

The antifoggant of the present invention may be added by any method such as a solution, a powder and a dispersion of solid fine particles. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

Although not required to practice the present invention,
It may be advantageous to add a mercury (II) salt as an antifoggant to the image forming layer. Preferred mercury (II) salts for this purpose are mercury acetate and mercury bromide. The amount of mercury used in the present invention is preferably 1 nmol to 1 mmol, more preferably 10 nmol to 100 mol per mol of silver applied.
It is in the range of μmmol.

The heat-developable image recording material of the present invention may contain benzoic acids for the purpose of increasing the sensitivity and preventing fog.
The benzoic acids of the present invention may be any benzoic acid derivative, but examples of preferred structures include those described in U.S. Pat.
No. 4,152,160, Japanese Patent Application No. 8-151242, No. 8-151241
And the compounds described in JP-A-8-98051 and the like. The benzoic acid of the present invention may be added to any part of the image recording material. However, it is preferable to add the benzoic acid to a layer having an image forming layer such as a photosensitive layer. More preferably, it is added to the silver salt-containing layer. The benzoic acid of the present invention may be added at any time during the preparation of the coating solution, and when it is added to the organic silver salt-containing layer, it may be added at any time from the preparation of the organic silver salt to the preparation of the coating solution. It is preferable after salt preparation and immediately before application. The method of adding the benzoic acids of the present invention includes powder, solution,
Any method such as a fine particle dispersion may be used. Also,
It may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent and a color tone agent. The benzoic acid of the present invention may be added in any amount, but is preferably from 1 μmol to 2 mol, more preferably from 1 mmol to 0.5 mol, per 1 mol of silver.

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

When a mercapto compound is used in the present invention, it may have any structure, but may be any of Ar-SM, Ar-SSA
Those represented by r are preferred. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring group or a condensed aromatic ring group having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring in these groups is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, Triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogens (e.g., Br and Cl), hydroxy, amino, carboxy,
Alkyl (e.g. one or more carbon atoms, preferably 1-4
Having one carbon atom) and alkoxy (e.g.,
One having at least one carbon atom, preferably having 1 to 4 carbon atoms). Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole,
Mercapto-5-methylbenzimidazole, 6-ethoxy-
2-mercaptobenzothiazole, 2,2'-dithiobis-benzothiazole, 3-mercapto-1,2,4-triazole, 4,5
-Diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4 (3H) -quinazolinone, 7-trifluoromethyl-
4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4 -
Thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydroxysil-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2-mercapto-4-methyl Pyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole,
Examples include 2-mercapto-4-phenyloxazole, but the present invention is not limited thereto.

The addition amount of these mercapto compounds is 0.0001 to 0.0001 per mol of silver in the emulsion layer as the image forming layer.
A range of 1.0 mole is preferred, more preferably from 0.001 to 0.3 mole per mole of silver.

In the image forming layer such as the photosensitive layer in the present invention, a polyhydric alcohol (for example, glycerin and diol of the kind described in US Pat. No. 2,960,404) and a plasticizer and a lubricant may be used. And fatty acids or esters described in US Pat. No. 3,121,060 and silicone resins described in British Patent No. 955,061.

The photothermographic emulsion of the present invention is contained in one or more layers on a support. One layer construction must include optional additional materials such as organic silver salts, silver halides, developers and binders, and toning agents, coating aids and other auxiliaries. The two-layer configuration is
One must contain the organic silver salt and silver halide in one emulsion layer (usually the layer adjacent to the support) and some other components in the second or both layers. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. The construction of a multicolor photothermographic material may include a combination of these two layers for each color, and may include all components in a single layer as described in U.S. Pat.No. 4,708,928. Is also good. In the case of a multi-dye, multi-color photothermographic material, each emulsion layer is generally, as described in U.S. Pat.No. 4,460,681,
By using a functional or non-functional barrier layer between each emulsion layer (photosensitive layer), it is kept distinct from each other.

In the photosensitive layer which is the image forming layer of the present invention, various dyes and pigments can be used from the viewpoint of improving color tone and preventing irradiation. Dyes and pigments used in the photosensitive layer of the present invention may be any, for example, pigments and dyes described in the Color Index, specifically, pyrazoloazole dye, anthraquinone dye, azo dye, azomethine dye, oxonol dye, Examples thereof include carbocyanine dyes, styryl dyes, triphenylmethane dyes, indoaniline dyes, indophenol dyes, organic pigments including phthalocyanine, and inorganic pigments. Preferred dyes used in the present invention include anthraquinone dyes (e.g., compounds 1 to 9 described in JP-A-5-341441, compounds 3-6 to 18 and 3-23 to 38 described in JP-A-5-165147), azomethine Dye (compound 17 described in JP-A-5-341441)
To 47 etc.), indoaniline dyes (e.g. JP-A-5-289227)
Nos. 11 to 19 and compounds described in JP-A-5-341441
47, compounds 2-10 to 11 described in JP-A-5-165147) and azo dyes (compounds 10 to 16 described in JP-A-5-341441). As a method for adding these dyes, any method such as a solution, an emulsion, a solid fine particle dispersion, and a state in which the dye is mordanted with a polymer mordant may be used. The amount of these compounds is determined by absorption of the purpose, generally the photosensitive material 1 m ²
It is preferable to use in a range of 1 μg or more and 1 g or less.

In the present invention, the antihalation layer can be provided on the side farther from the light source than the photosensitive layer. The antihalation layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less, more preferably an absorption of an exposure wavelength of 0.5 or more and 2 or less, and an absorption in a visible region after processing of 0.001 or more. It is preferably less than 0.5, and more preferably a layer having an optical density of 0.001 or more and less than 0.3.

When antihalation dyes are used in the present invention, these dyes have the desired absorption in the wavelength range, have a sufficiently low absorption in the visible region after treatment, and have the desirable absorbance spectrum shape of the antihalation layer. Any compound can be used as long as it is possible. For example, the following are disclosed, but the present invention is not limited thereto. As a single dye, JP-A-59-56458, JP-A-Hei 2-
216140, 7-13295, 711432, U.S. Patent 5,380,
No. 635, JP-A-2-68539, page 13, lower left column, line 1 to page 14, lower left column, line 9, and JP-A-3-24539, page 14, lower left column, page 16, lower right column The dyes that can be decolorized by the treatment include JP-A-52-139136, JP-A-53-132334, and
56-501480, 57-16060, 57-68831, 57-1018
No. 35, 59-182436, JP-A-7-36145, 7-199409
No., JP-B-48-33692, JP-B-50-16648, JP-B2-41734
Nos., U.S. Pat.Nos. 4,088,497, 4,283,487, 4,548,89
No. 6 and 5,187,049.

The heat-developable image recording material of the present invention has an image forming layer such as a photosensitive layer containing at least one silver halide emulsion on one side of a support, and a back layer ( It is preferably a so-called single-sided image recording material having a backing layer).

In the present invention, the back layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less,
More preferably absorption is 0.5 or more and 2 or less, and the absorption in the visible region after the treatment is preferably 0.001 or more and less than 0.5, and more preferably a layer having an optical density of 0.001 or more and less than 0.3. . Examples of the antihalation dye used in the back layer are the same as those of the antihalation layer described above.

US Pat. Nos. 4,460,681 and 4,374,9
Backside resistive heating layer as shown in No. 21
stive heating layer) can also be used in a photosensitive heat developed photographic image system.

A hardener may be used for each layer such as the image forming layer and the back layer of the present invention. Examples of the hardener include U.S. Pat.No.4,281,060, polyisocyanates described in JP-A-6-208193, epoxy compounds described in U.S. Pat.No.4,791,042, JP-A-62-89048. For example, vinyl sulfone compounds described in US Pat.

The heat-developable image-recording material of the present invention may be developed by any method, but is usually developed by raising the temperature of the image-wise exposed image-wise material. As a preferred embodiment of the heat developing machine used, as a type in which the heat-developable image forming material is brought into contact with a heat source such as a heat roller or a heat drum, Japanese Patent Publication No. 5-56499, Patent Publication No. 684453, JP-A-9-292695, JP-A-9-297385 and International Patent WO
No. 95/30934, a non-contact type thermal developing machine disclosed in JP-A-7-13294, International Patent WO 97/28489, and 97/2848
Nos. 8 and 97/28487. A particularly preferred embodiment is a non-contact type thermal developing machine. The preferred development temperature is 80 to 250 ° C, more preferably 100 to 140 ° C. The development time is preferably from 1 to 180 seconds, more preferably from 10 to 90 seconds.

As a method for preventing the processing unevenness of the heat-developable image recording material of the present invention due to the dimensional change at the time of the heat development described above,
A method in which an image is not formed at a temperature of 80 ° C. or more and less than 115 ° C. (preferably 113 ° C. or less), heated for 5 seconds or more, and then thermally developed at 110 ° C. or more (preferably 130 ° C. or less) to form an image ( A so-called multi-stage heating method) is effective.

The image recording material of the present invention may be exposed by any method, but a laser beam is preferred as an exposure light source. As laser light according to the present invention, gas laser,
YAG lasers, dye lasers, semiconductor lasers and the like are preferred. Further, a semiconductor laser and a second harmonic generation element can be used.

The image recording material of the present invention has a low haze upon exposure and tends to cause interference fringes. Examples of this interference fringe prevention technology include a technology in which a laser beam is obliquely incident on an image recording material as disclosed in JP-A-5-113548 and a multi-mode disclosed in WO95 / 31754 and the like. Methods using lasers are known, and it is preferable to use these techniques.

For exposing the image recording material of the present invention, SPIE
vol.169 Laser Printing 116-128 (1979), JP 4-5
As disclosed in No. 1043, WO95 / 31754, etc., it is preferable to expose the laser beams so as to overlap each other so that scanning lines are not visible.

FIG. 1 shows an example of the configuration of a heat developing machine used in the heat development of the heat-developable image recording material of the present invention. FIG. 1 is a side view of the heat developing machine. A transfer endless belt 4 suspended by a plurality of feed rollers 3 is pressed against the peripheral surface of a cylindrical heat drum 2 containing a halogen lamp 1 as a heat source therein as a heat source of the heating means, and the endless belt 4 and the heat drum The heat-developable image recording material 5 is conveyed by being sandwiched therebetween. While being transported, the heat-developable image recording material 5 is heated to a development temperature, and is subjected to heat development. In this case, the orientation of the lamp is optimized, and the temperature control in the width direction is performed accurately.

In the vicinity of the outlet 6 from which the heat-developable image recording material 5 is sent out between the heat drum 2 and the endless belt 4, the heat-development forming material 5 released from the curvature of the peripheral surface of the heat drum 2 is flattened. A correction guide plate 7 is provided. In the vicinity of the correction guide plate 7, the ambient temperature is adjusted so that the temperature of the heat-developable image recording material 5 does not fall below a predetermined temperature.

A pair of feed rollers 8 for feeding the heat-developable image recording material 5 is provided downstream of the outlet 6, and the heat-developable image recording material 5 is maintained in a flat state downstream of the outlet 6 adjacent to the roller pair 8. A pair of flat guide plates 9 for guiding in such a state is installed, and further downstream thereof, another pair of feed rollers 10 is installed adjacent to the flat guide plates 9. The flat guide plate 9 has a length sufficient to cool the heat-developable recording material 5 while the heat-developable image recording material 5 is being conveyed therebetween. That is, the heat development recording material 5 is cooled until the temperature of the heat development recording material 5 becomes 30 ° C. or less. As this cooling means, a cooling fan 11 is provided.

Although the above has been described with reference to the drawings, the present invention is not limited to this. For example, the thermal developing machine used in the present invention, such as that described in JP-A-7-13294, may have various structures. Also, when performing a multi-stage heating method,
In the above-described apparatus, two heat sources having different heating temperatures are used.
It is sufficient to install more than one unit and heat them continuously at different temperatures.

[0275]

EXAMPLES The present invention will be described below in detail with reference to Examples along with Synthesis Examples of a crosslinkable core-shell latex, but the present invention is not limited to only the following Examples.

<Synthesis Example 1><< Synthesis of Core Latex (1-C) >> 110 g of water
A solution obtained by adding 1 g of sodium dodecylbenzenesulfonate to 4.0 g of a 1N aqueous solution of sodium hydroxide was heated to 70 ° C., and a solution of 0.25 g of potassium persulfate dissolved in 20 g of water was added thereto. A mixture of 0.0 g and 5.0 g of divinylbenzene was added over 2 hours. 1
After emulsion polymerization for a period of time, a solution prepared by dissolving 0.12 g of potassium persulfate in 10 g of water was added, and the mixture was heated at 80 ° C. for 3 hours. Then, 1N sodium hydroxide was added to adjust the pH to 5.0 to 6.0. An aqueous solution was added. The obtained latex (1-C) as a core is a milky blue good latex having a pH of 5.0.
5. The solid concentration was 25.2% by weight.

<< Crosslinkable core-shell type latex (1-C)
Synthesis of S) >> Latex (1-C) 7 obtained above
A solution obtained by adding 56 g of water to 9.3 g was heated to 70 ° C., and a solution obtained by dissolving 0.05 g of potassium persulfate in 2 g of water was added.
A mixture of 4.0 g and 6.0 g of glycidyl methacrylate was added over 3 hours. After emulsion polymerization for 1 hour, a solution prepared by dissolving 0.05 g of potassium persulfate in 2 g of water was added,
After heating at 80 ° C. for 3 hours, a 1N aqueous sodium hydroxide solution was added so that the pH became 5.0 to 6.0. The obtained crosslinkable core-shell type latex (1-CS) is a milky blue good latex having a pH of 5.5 and a solid concentration of 2
4.3% by weight. The Tg of the core polymer
Is 100 to 105 ° C., and the Tg of the polymer in the shell portion is
Was 45-50 ° C.

<Synthesis Example 2><< Synthesis of Crosslinkable Core-Shell Latex (2-CS) >>
In the synthesis of the crosslinkable core-shell latex of Synthesis Example 1, 18.0 g of ethyl acrylate and N-
Synthesis was performed in the same manner as in Synthesis Example 1 except that a mixture of 2.0 g of methylol acrylamide was used. The obtained crosslinkable core-shell latex (2-CS) was a milky white good latex having a pH of 6.5 and a solid content of 24.0% by weight. In addition, Tg of the polymer of the shell part is -15 to -10
° C.

<Synthesis Example 3><< Synthesis of Crosslinkable Core-Shell Type Latex (3-CS) >>
In the synthesis of the crosslinkable core-shell latex of Synthesis Example 1, 16.0 g of butyl methacrylate and 2
Synthesis was performed in the same manner as in Synthesis Example 1 except that a mixture of 4.0 g of -isopropenyl-2-oxazoline was used. The obtained crosslinkable core-shell latex (3-CS) was a milky white good latex having a pH of 6.0 and a solid content of 24.1% by weight. The Tg of the polymer in the shell part is 15 to
20 ° C.

<Synthesis Example 4><< Synthesis of Crosslinkable Core-Shell Latex (4-CS) >>
Same as Synthesis Example 1 except that a mixture of 10.0 g of ethyl methacrylate, 6.0 g of butyl acrylate, and 4.0 g of 2-hydroxyethyl methacrylate was used as a monomer in the synthesis of the crosslinkable core-shell latex of Synthesis Example 1. Was synthesized. The obtained crosslinkable core-shell type latex (4-CS) is a milky white good latex having a pH of 6.
0, and the solid concentration was 24.2% by weight. The Tg of the polymer in the shell was 13 to 18 ° C. Other crosslinkable core-shell type polymer latexes were synthesized in the same manner.

Example 1 << Preparation of Silver Halide Emulsion >> (Emulsion A) 11 g of gelatin (2700 ppm in terms of calcium content), 30 mg of potassium bromide, and 10 mg of sodium benzenethiosulfonate were dissolved in 700 ml of water, and the temperature was 55%. PH at ℃
After adjusting to 5.0, 159 ml of an aqueous solution containing 18.6 g of silver nitrate and an aqueous solution containing 1 mol / l of potassium bromide were added over 6 minutes and 30 seconds by a control double jet method while keeping the pAg at 7.7. Then, 476 ml of an aqueous solution containing 55.5 g of silver nitrate
And an aqueous solution of a halogen salt containing potassium bromide at 1 mol / l was added over 28 minutes and 30 seconds by the control double jet method while maintaining the pAg at 7.7. Thereafter, the pH was lowered to perform coagulation sedimentation and desalting treatment, and 0.17 g of compound A and 23.7 g of deionized gelatin (calculated as 20 ppm or less) were added to adjust the pH to 5.9 and pAg 8.0. The obtained particles have an average particle size of 0.11 μm, a projection area variation coefficient of 8%, and a (100) face ratio of 93.
% Cubic particles.

The silver halide grains thus obtained were heated to 60 ° C., and 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver, and after 3 minutes, 154 μm of sodium thiosulfate was added.
Mole was added and aged for 100 minutes.

Thereafter, the temperature was maintained at 40 ° C.
6.4 × 10 ^-4 mole of sensitizing dye A per mole, 6.4 × 10 ^-3
Molar compound B was added with stirring, and after 20 minutes, the mixture was rapidly cooled to 30 ° C. to complete the preparation of silver halide emulsion A.

[0284]

Embedded image

<< Preparation of Silver Organic Acid Dispersion >><Silver Organic Acid A> 4.4 g of arachiic acid, 39.4 g of behenic acid, 700 ml of distilled water, and 70 ml of tert-butanol were stirred at 85 ° C. under 1N.
-103 ml of an aqueous solution of NaOH was added over 60 minutes and reacted for 240 minutes.
The temperature was lowered to 5 ° C. Then, 112.5 ml of an aqueous solution of 19.2 g of silver nitrate
Was added over 45 seconds, allowed to stand for 20 minutes, and cooled to 30 ° C. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of the filtrate became 30 μS / cm. The solid content thus obtained was treated as a wet cake without drying, and 5 g of polyvinyl alcohol (trade name: PVA-205) and water were added to a wet cake equivalent to 100 g of dry solid content to make the total amount 500 g. It was pre-dispersed with a homomixer.

Next, the pre-dispersed stock solution is dispersed in a dispersing machine (trade name: Microfluidizer M-110S-EH, manufactured by Microfluidics International Corporation, using G10Z interaction chamber).
The pressure was adjusted to 1750 kg / cm ² , and the mixture was treated three times to obtain an organic acid silver dispersion A. The organic acid silver particles contained in the organic acid silver dispersion thus obtained have an average minor axis of 0.04 μm and an average major axis of 0.8 μm.
m, needle-like particles having a variation coefficient of 30%. The measurement of the particle size was performed by MasterSizerX manufactured by Malvern Instruments Ltd. In the cooling operation, a coiled heat exchanger was mounted before and after the interaction chamber, and the temperature of the refrigerant was adjusted to a desired dispersion temperature.

<< Preparation of solid fine particle dispersion of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane >> 1,1-bis (2-hydroxy-3, 5-dimethylphenyl) -3,5,5-trimethylhexane 20 g for Kuraray Co., Ltd.
3.0 g of MP-203 made of MP polymer and 77 ml of water were added, and the mixture was stirred well and left as a slurry for 3 hours. Then 0.5
360 g of zirconia beads having a diameter of 360 mm were prepared and placed in a vessel together with the slurry, and dispersed with a dispersing machine (1 / 4G sand grinder mill: manufactured by Imex Co., Ltd.) for 3 hours to prepare a dispersion of solid fine particles of a reducing agent. The particle size is 80 wt% of the particles 0.3
It was not less than μm and not more than 1.0 μm.

<< Preparation of Solid Fine Particle Dispersion of Tribromomethylphenyl Sulfone >> Hydroxypropylmethylcellulose was added to 30 g of tribromomethylphenylsulfone.
0.5 g, 0.5 g of compound C and 88.5 g of water were added, stirred well, and left as a slurry for 3 hours. Thereafter, a solid fine particle dispersion of the antifoggant was prepared in the same manner as the preparation of the reducing agent solid fine particle dispersion. Particle size is 80μ% of particles 0.3μm
It was 1.0 μm or less.

[0289]

Embedded image

<< Preparation of Image Forming Layer Coating Solution >>Binder; SBR latex LACSTAR 3307B solid content: 470 g (manufactured by Dainippon Ink and Chemicals, Inc.) based on 1 mol of silver of organic acid silver A prepared above. 1-bis (2-hydroxy-3,5-dimethylphenyl-3,5,5-trimethylhexane) 110 g surfactant; compound D 5 g tribromomethylphenyl sulfone 25 g sodium benzenethiosulfonate 0.25 g hydrophilic polymer; compound E 46 g 6-iso-butylphthalazine 0.12 mol Ultra-high contrast agent (nucleating agent); compound F 1.8 g compound G 6.5 g compound H 8.5 g dye A 0.62 g silver halide emulsion A 0.05 mol was added as Ag amount. , Water and further adjusted to pH 6.5 with 1N sulfuric acid,
An image forming layer coating solution was obtained.

[0291]

Embedded image

<< Preparation of Coating Solution for Emulsion Surface Protective Layer >> Compound I was added in an amount of 0.125 to 180 g of the crosslinkable core-shell latex of Synthesis Example 1.
g, 1,3-dimethylolethylene urea 0.86 g, carnauba wax (manufactured by Chukyo Yushi Co., Ltd .; Cellosol 524) 30 wt% solution 2.5 g, polyvinyl alcohol (manufactured by Kuraray Co., Ltd .; PVA-
235) 2.3 g and a matting agent (polymethyl methacrylate,
0.5 g of an average particle size of 5 μm) was added to prepare a coating solution.

[0293]

Embedded image

<< Preparation of PET Support with Back / Undercoat Layer >> (1) Support Using terephthalic acid and ethylene glycol, IV (intrinsic viscosity) = 0.66 (phenol / tetrachloroethane = 6 / 4 (measured at 25 ° C. in weight ratio). This was pelletized, dried at 130 ° C. for 4 hours, melted at 300 ° C., extruded from a T-die, and then quenched to prepare an unstretched film having a thickness of 120 μm after heat setting. .

Using a roll having a different peripheral speed, the film was longitudinally stretched 3.3 times and then transversely stretched 4.5 times with a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After that, it was heat-set at 240 ° C. for 20 seconds and relaxed 4% in the lateral direction at the same temperature. Then, after slitting the chuck part of the tenter, knurling is performed on both ends, and 4.8 kg / cm ²
Rolled up. In this way, width 2.4m, length 3500m,
A roll having a thickness of 120 μm was obtained.

(2) Undercoat layer (a) Polymer latex-styrene / butadiene / hydroxyethyl methacrylate / divinylbenzene = 67/30 / 2.5 / 0.5 (% by weight) 160 mg / m ² 2,4-dichloro-6-hydroxy- s-Triazine 4mg / m ² Matting agent (polystyrene, average particle size 2.4μm) 3mg / m ²

(3) Undercoat layer (b) Alkali-treated gelatin (Ca ²⁺ content 30 ppm, jelly strength 230 g) 50 mg / m ²

(4) Conductive Layer Jurimar ET-410 (manufactured by Nippon Pure Chemical Co., Ltd.) 96 mg / m ² Gelatin 50 mg / m ² Compound A 0.2 mg / m ² Polyoxyethylene phenyl ether 10 mg / m ² Sumitex Resin M -3 18 mg / m ² (water-soluble melamine compound, manufactured by Sumitomo Chemical Co., Ltd.) Dye A Coating amount at which the optical density of 780 nm becomes 1.0 SnO ₂ / Sb (9/1 weight ratio, needle-like fine particles, long axis / short axis) Shaft = 20-30 Ishihara Sangyo Co., Ltd.) 160 mg / m ² Matting agent (polymethyl methacrylate, average particle size 5 μm) 7 mg / m ²

(5) Protective layer Polymer latex-(methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 59/9/26/5/1 (weight% copolymer)) 1000 mg / m ² of polystyrene sulfonate (molecular weight of 1000-5000) 2.6 mg / m ² Cellosol 524 (Chukyo Yushi Co.) 25 mg / m ² Sumitex resin M-3 (water-soluble melamine compound by Sumitomo chemical Co., Ltd. ) 218mg / m ²

Undercoat layer (a) and undercoat layer (b) on one side of the support
Were sequentially applied and dried at 180 ° C. for 4 minutes. Then, a conductive layer and a protective layer are sequentially coated on the opposite side to which the undercoat layer (a) and the undercoat layer (b) have been applied, and dried at 180 ° C. for 30 seconds, respectively, for a PET support having a back / undercoat layer. It was created.

The PET support provided with the back / undercoat layer thus prepared was placed in a heat treatment zone having a total length of 30 m set at 150 ° C., and was transported under its own weight at a tension of 14 g / cm ² and a transport speed of 20 m / min. After that, pass it through the zone of 40 ° C for 15 seconds, 10kg / cm ²
At a take-up tension of

<< Preparation of heat-developable image recording material >> On the side of the PET support provided with the back / undercoat layer (a) and the undercoat layer (b), the side provided with the undercoat layer (a) and the undercoat layer (b). The image forming layer and the emulsion surface protective layer were simultaneously coated on the emulsion surface protective layer so as to have a coating amount of 1.6 g / m ² and a coating amount of the solid content of the polymer latex of the protective layer of 2 g / m ^2. The sample was dried at 3 ° C. for 3 minutes to prepare a sample. This is designated as Sample No. 1.

In place of the crosslinkable core-shell type latex of Synthesis Example 1 used in << Preparation of Coating Solution for Emulsion Surface Protective Layer >> of Sample No. 1, 180 g of the latex of Synthesis Example 2 was used.
-Duranate W instead of dimethylol ethylene urea
Other than using 2 g of B40-80D (80% by weight solution),
Sample No. 2 of the heat-developable image recording material was prepared in the same manner as in Test No. 1.

In place of the crosslinkable core-shell type latex of Synthesis Example 1 used in << Preparation of Coating Solution for Emulsion Surface Protective Layer >> of Sample No. 1, 180 g of the latex of Synthesis Example 3 was used.
-Duranate W instead of dimethylol ethylene urea
Other than using 2 g of B40-80D (80% by weight solution),
Sample No. 3 of the heat-developable image recording material was prepared in the same manner as in Test No. 1.

180 g of the latex of Synthesis Example 4 was used instead of the crosslinkable core-shell type latex of Synthesis Example 1 used in << Preparation of Coating Solution for Emulsion Surface Protective Layer >> of Sample No. 1,
-Duranate W instead of dimethylol ethylene urea
Other than using 2 g of B40-80D (80% by weight solution),
Sample No. 4 of the heat-developable image recording material was prepared in the same manner as in Test No. 1.

Instead of the latex of Synthesis Example 1 used in << Preparation of Coating Solution for Emulsion Surface Protective Layer >> of Sample No. 1, a polymer latex of methyl methacrylate / styrene / 2-ethylhexyl acrylate = 61/11/28 (% by weight) Solid content concentration
Compound J was used as a film-forming aid in an amount of 6.7 g.
Sample No. 5 of a heat-developable image recording material (Comparative Example) was prepared in the same manner as in Sample No. 1 except that g was used and 1,3-dimethylolurea was not used.

[0307]

Embedded image

The obtained samples were evaluated for photographic properties, suitability for heat development, and suitability for opaque according to the following evaluation methods.

(1) Evaluation of photographic performance (exposure processing) The obtained sample was exposed to xenon flash light having an emission time of 10 ^-6 seconds through an interference filter having a peak at 780 nm and a step wedge.

(Heat Developing Process) The exposed sample was subjected to a heat developing process at 117 ° C. for 20 seconds using the heat developing machine shown in FIG. In the drum type heat developing machine of FIG. 1, the light distribution of the lamp was optimized, and the temperature accuracy in the width direction was set at ± 1 ° C. Further, the temperature of the heat-developable image recording material in the vicinity of the correction guide plate 7 is 90 °.
The ambient temperature was adjusted so that the temperature did not fall below ℃.

(Evaluation of Photographic Performance) The obtained images were evaluated by a Macbeth TD904 densitometer (visible density). The results of the measurement were evaluated in terms of Dmin, sensitivity (the reciprocal of the ratio of the exposure amount giving a density higher than Dmin by 1.0), and contrast. Contrast was represented by the slope of a straight line connecting points of density 0.3 and 3.0, with the logarithm of the exposure amount as the horizontal axis.

(2) Suitability for heat development treatment Using the heat development machine shown in FIG. 1, the sample was passed through the sample so that the surface having the image forming layer was on the heat drum side, and the ease of peeling of the sample from the heat drum was evaluated. did. △ and △ are practically acceptable levels. ：: Natural peeling. Δ: When peeling is given, the film is naturally peeled thereafter. X: It is necessary to forcibly peel off.

(3) Suitability for Opaque The brush was soaked with toluene, and the image portion of the sample on which an image was formed was rubbed 5 to 6 times, and the disturbance of the image after the toluene was dried was evaluated. △ and △ are practically acceptable levels. ：: No change in image. Δ: Image is slightly disturbed. X: The image was disturbed and the film was destroyed. Table 23 shows the results. The table also shows the gel fraction of the protective layer determined as described above.

[0314]

[Table 23]

From the results in Table 23, it can be seen that the recording material using the crosslinkable core-shell type latex for the protective layer is a heat-developable image recording material having good heat development suitability and opaque suitability without impairing photographic performance. Understand.

Example 2 The polymer latex (methyl methacrylate / styrene / 2-ethylhexyl acrylate = 61/11/28 (% by weight)) of the emulsion surface protective layer of Sample No. 5 (Comparative Example) of Example 1 was not used. It was used as a crosslinkable polymer latex, and the ratio (weight ratio of solid content) to the crosslinkable core-shell latex obtained in Synthesis Examples 1 to 4 was adjusted as shown in Table 24. A sample was prepared in the same manner as in Example 1 except that the emulsion surface protective layer was formed by combining a cross-linking agent and the like in the same manner as in Sample Nos. These samples were evaluated for photographic performance, suitability for heat development, and suitability for opaque in the same manner as in Example 1. Table 24 shows the results.

[0317]

[Table 24]

As is clear from Table 24, the samples using the crosslinkable core-shell latex of the present invention as the binder for the protective layer and having the gel fraction of the protective layer of 40% by weight or more did not impair the photographic performance. It can be seen that the suitability for development processing and the suitability for opaque are good.

[0319]

According to the present invention, a heat-developable image recording material having excellent opaque suitability and heat developability can be obtained while maintaining good photographic performance.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration example of a heat developing machine used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Halogen lamp 2 Heat drum 3 Feed roller 4 Endless belt 5 Thermally developed image recording material 6 Outlet 7 Guide plate 8 Feed roller pair 9 Flat guide plate 10 Feed roller pair 11 Cooling fan

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yasuya Sakurai 210 Nakanuma, Minamiashigara-shi, Kanagawa Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 2H123 AB00 AB03 AB23 AB28 BA00 BA14 BA49 CB00 CB03

Claims (4)

[Claims] 1. An image forming layer comprising at least one image forming layer comprising an organic silver salt, a reducing agent and a photosensitive silver halide on a support,
In the heat-developable image recording material having at least one protective layer provided on the image forming layer, a polymer latex is used as a binder of the image forming layer, and a crosslinkable core-shell type latex is used as a binder of the protective layer. A heat-developable image recording material, wherein a polymer latex is used, and the gel fraction of the protective layer is from 40% by weight to 100% by weight. 2. The crosslinkable core-shell type latex used in the protective layer has a functional group in a shell part, and a glass transition temperature of a core part is higher than a glass transition temperature of a shell part. The heat-developable image recording material according to claim 1, wherein a cross-linking agent having a functional group capable of reacting with the cross-linkable core-shell type latex is used in the protective layer. 3. The crosslinkable core-shell type latex used in the protective layer has a functional group in a shell portion, and a glass transition temperature of the core portion is higher than a glass transition temperature of the shell portion. The heat-developable image recording material according to claim 1, wherein a polymer latex having a functional group capable of reacting with a crosslinkable core-shell type latex is used in the protective layer. 4. The functional group contained in the crosslinkable core-shell type latex includes a hydroxyl group, an isocyanate group,
The heat-developable image recording material according to any one of claims 1 to 3, wherein the material is selected from a 2-oxazolinyl group, an N-methylol group, and an epoxy group.