JP2001142175A - Heat developable material, developing method and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat developable material giving a high sharpness image by heat development, containing a heat decolorable dye excellent in heat decolorability and having a slight residual color and high stability in storage, excellent in shelf stability particularly at high humidity, less liable to cause the contamination and deterioration of a heat roller due to the heat decolorable dye in development, excellent in stability in long-term running and less liable to form interference fringes on an image in exposure with laser light and to provide a method for developing the heat developable material and an image forming method. SOLUTION: The heat developable material has a photosensitive layer containing photosensitive silver halide particles, an organic silver salt and a reducing agent and a non-photosensitive layer on the substrate and contains a dye of formula 1 which is decolored by heat at 80-200 deg.C, e.g. a dye of formula 2 in the photosensitive layer or the non-photosensitive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable material for forming an image by heat development.
Uses a dye that prevents halation and irradiation, can improve sharpness, and has excellent storage stability without discoloration after thermal development and without disturbing residual color or color tone. Also, the present invention relates to a heat developing material having a small change in color tone even when stored under high humidity.

[0002] Furthermore, the present invention relates to a developing method using a heat roller which does not cause deformation or discoloration in thermal development for a long period of time and an image forming method for performing vertical multi-scan laser exposure.

[0003]

2. Description of the Related Art In recent years, in the fields of medical care and printing, there has been a strong demand for a heat-developable light-sensitive material which does not produce waste liquid due to wet processing in view of environmental protection and workability. In particular, there is a need for a technique relating to a photothermographic material for photographic technology, which can form a high-resolution, clear black image by thermal development. Since these photothermographic materials are usually developed at a temperature of 80 ° C. or higher, they are called heat development materials.

Conventionally, in this type of heat developing material, in addition to the photosensitive layer, the light irradiated to the photosensitive layer is not absorbed but passes through and irregularly reflected at the interface of the support, the intermediate layer or the adhesive layer. An anti-irradiation layer (AI layer) or a backing layer (BC layer) is provided. The AI layer is mainly set between the photosensitive layer and the support, and the BC layer is set on the opposite side of the support with respect to the support. For the AI layer and the BC layer, a dye that efficiently absorbs the main wavelength for photosensitivity is used. Even if the dye is necessary at the time of exposure, if the dye remains after development, the residual color due to absorption of the visible part will be generated, which will hinder the identification of the silver image. Had to be lowered. For this reason, it has been considered to use a dye that decomposes and decolors by heat during development (hereinafter, also simply referred to as a thermal decoloring dye) as the heat developing material. Examples of the heat-developable material using the above-mentioned heat-decolorable dye include, for example, U.S. Patent Nos. 3,745,009, 4,033,948, 4,524,128, 4,594,312, 4,994,356, 5,135,842, 5,314,795, 5,324,627, 5,384,237, European Patent 911,693, etc. The book is known. However, conventionally, there is no dye exhibiting good properties for a heat-developable material, and the amount of the dye used is reduced to a level that does not cause residual color, or a dye in the infrared region having a small absorption in the visible part is used. And so on.

Further, even if the decoloring property of the dye during heat development is good, the dye is decomposed by, for example, contact between the heat roller and the heat development material during development, and the decomposed product adheres to the heat roller. This is transferred to the next heat development material to generate stains.Because the dye has the property of being easily decomposed by heat or the like, the storage stability of the dye itself and the heat development material having a layer containing the dye is poor. Defects such as dye decomposed products are repeatedly deposited on the roller, causing the unevenness of the roller surface and causing uneven development, and other defects such as the dye itself and decomposed products evaporating and reacting with the material of the heat roller to deteriorate the physical properties. Had.

Accordingly, as for the heat roller, a heat-resistant material having low chemical reactivity has been searched for, and silicone rubber, norbornene-olefin rubber and the like have been studied, but the uniformity of development has been insufficient. Further, since the phase of the incident light of the laser exposure and the reflected light at the interface of the constituent layers constituting the heat development material are shifted by the refractive index and the film thickness of the constituent layers, or the incident angle and the reflection angle, the light amount is amplified or Numerous countermeasures have been studied for the type of dye and laser exposure method, etc. for the phenomenon that the image quality is impaired due to attenuating and drawing a specific pattern that is unique, so-called interference fringes. The fact is that no method has been found.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image obtained by heat development with high sharpness, excellent heat decoloring properties of a heat decolorable dye, little residual color, and heat decoloration during storage. High stability of color dyes, especially excellent storage stability under high humidity, less occurrence of heat roller stains and deterioration of rollers due to thermal decoloring dye during development, excellent stability during long-term running Another object of the present invention is to provide a heat-developable material having characteristics such as that interference fringes are hardly generated on an image by laser exposure, a method for developing the heat-developable material, and an image forming method.

[0008]

The above object is achieved by the following constitution.

1. Photosensitive silver halide grains on a support,
In a heat developing material having a photosensitive layer and a non-photosensitive layer containing an organic silver salt and a reducing agent, in the photosensitive layer or the non-photosensitive layer,
A heat-developable material comprising a dye represented by the following general formula (1) and decolorable by heat at 80 to 200 ° C.

[0010]

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In the formula, R ¹ is a hydrogen atom, an aliphatic group which may have a substituent, an aromatic group which may have a substituent, NR ¹¹
R ¹² , OR ¹¹ or SR ¹¹ , R ¹¹ and R ¹² independently represent a hydrogen atom, an aliphatic group or an aromatic group which may have a substituent, and R ¹¹ and R ¹² are A hetero ring containing a nitrogen atom may be formed. R ² represents a hydrogen atom, an aliphatic group which may have a substituent, or an aromatic group. Z ¹ represents a heterocyclic group containing a nitrogen atom, and Z ² represents an aromatic group having no nitrogen atom. L ¹ is a divalent linking group having an even number of methine chains, X
Represents an anionic group.

2. 2. The heat-developable material as described in 1 above, wherein the heat-decolorable dye contains a base-generating precursor compound represented by the following general formula (2).

[0013]

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In the formula, Z ³ and Z ⁴ are atoms necessary for forming a 4- to 9-membered ring which may have a substituent, L ² is a divalent linking group, and Y is a substituent. Represent. n represents a positive number of 0 ≦ n ≦ 4, and when n is 2 or more, adjacent substituents may form a ring.

3. The heat-decolorable dye-containing layer has a concentration of the dye with respect to the main wavelength of light of 0.20 or more, and has a layer which is coated so as to be 0.18 or less after heat development. 3. The heat-developable material as described in 1 or 2, above.

4. The heat-developable material as described in any one of the above items 1 to 3, wherein the layer containing a dye which is decolored by heat contains a latex having a glass transition temperature of -20 to 80 ° C.

5. The heat-developable material as described in any one of the above items 1 to 4, wherein the layer containing a dye which is decolored by heat contains a polyhalomethane compound represented by the following general formula (3).

[0018]

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In the formula, Q represents an aromatic group or a heterocyclic group which may have a substituent, L ³ represents a divalent linking group, and X represents a halogen atom.

6. 6. A method for developing a heat-developable material, wherein the development of the heat-developable material according to any one of 1 to 5 is performed using a heat roller made of silicone rubber containing a metal oxide.

7. 7. The method of claim 6, wherein at least a part of the metal oxide is a surface-treated iron oxide.

8. 6. An image forming method, wherein the image exposure of the heat-developable material according to any one of 1 to 5 is performed using a vertical multi-type laser exposure machine.

Hereinafter, the present invention will be described in detail. The heat-developable material of the present invention usually has a structure in which at least one photosensitive layer and a non-photosensitive layer are provided on a support, and the non-photosensitive layer is provided below the photosensitive layer (between the support and the photosensitive layer). A provided for
I layer, a protective layer provided on the photosensitive layer, a BC layer provided on the opposite side of the photosensitive layer with respect to the support, a protective layer provided on the BC layer, and the like. The photosensitive layer mainly contains silver halide, an organic silver salt, a reducing agent and a polymer binder. The non-photosensitive layer mainly comprises A
In the I layer and the BC layer, a thermal decoloring dye represented by the general formula (1) of the present invention, which has a high absorption efficiency with respect to the photosensitive wavelength and a good thermal decoloring property, is present. Degradation of sharpness due to irregular reflection at the interface of the constituent layers and occurrence of interference fringes are prevented. The thermal decolorable dye may be contained in a protective layer such as a photosensitive layer and a non-photosensitive layer within a range that does not impair the image characteristics of the heat developing material.

Further, the photosensitive layer and the non-photosensitive layer, in particular, the AI layer and the BC layer are contained in the general formula (B) in which the basic property of the layer is increased by heat in order to improve the thermal decoloring property of the thermal decoloring dye contained therein. The base-generating precursor compound represented by 2) can be contained.

The photosensitive layer and the non-photosensitive layer (protective layer,
The AI layer and the BC layer (including the AI layer and the BC layer) preferably contain a polymer binder, and in particular, a latex capable of providing a site for a decoloring reaction for enhancing the decoloring property of the thermal decoloring dye. Further, it is preferable that the photosensitive layer and the non-photosensitive layer, in particular, the AI layer and the BC layer contain a polyhalomethane compound which acts as a catalyst when decoloring or reducing the concentration of the thermal decoloring dye.

The decolorizing dye represented by the general formula (1), the base-generating precursor compound represented by the general formula (2), the above-mentioned polymer binder, particularly latex, a polyhalomethane compound acting as a catalyst, and others used for thermal development. The configuration of the heat developing roller, the laser exposure method, the developing method, and the like will be sequentially described. <Thermal Decoloring Dye of General Formula (1)> The general formula (1) showing the thermal decoloring dye of the present invention will be described in more detail.

In the formula, R ¹ is a hydrogen atom, an aliphatic group which may have a substituent, an aromatic group which may have a substituent, NR ¹¹
R ¹² , OR ¹¹ or SR ¹¹ , R ¹¹ and R ¹² independently represent a hydrogen atom, an aliphatic group or an aromatic group which may have a substituent, and R ¹¹ and R ¹² are A hetero ring containing a nitrogen atom may be formed. R ² represents a hydrogen atom, an aliphatic group which may have a substituent, or an aromatic group. Z ¹ represents a nitrogen-containing heterocyclic group, and Z ² represents an aromatic group having no nitrogen atom. L ¹ represents a divalent linking group having an even number of methine chains, and X represents an anionic group.

As the substituent of R ^1, an optionally substituted alkoxy group (methoxy group, ethoxy group, propyloxy group, butoxy group, octoxy group, dodecanoxy group, docosanoxy group, 2-ethylhexanoxy group) ,
Halogenated alkoxy groups (trifluoromethoxy group, perfluorooctanol group), cycloalkoxy groups (cyclohexanoxy group, cyclooctanoxy group, cyclopentanoxy group, etc.), aromatic groups (phenoxy group, naphthenoxy group) ), Heterocyclic groups (pyridyl group, furyl group, thiophenyl group, piperazyl group, imidazolyl group, triazole group, tetrazole group, etc.), alkylamino groups (methylamino group, propylamino group, octylamino group, tetradecyl group), Dialkylamino group (dimethylamino group,
Represents a diethylamino group, a dioctylamino group) or an alkylthio group (a methylthio group, an ethylthio group, a butylthio group, an octylthio group), and the alkyl group portion preferably has 1 to 25 carbon atoms. Particularly preferred groups among the heterocyclic groups are a phenoxazine group (phenoxazine group, 2,7-dichlorophenoxazine), a phenothiazine group (phenothiazine group, 2,8-dichlorophenothiazine group, 2,8
-Difluorophenothiazine group, 2,3,7,8-tetradichlorophenothiazine group), carbazole group (carbazole group, 2,7-dichlorocarbazole group, 2,7-
Difluorocarbazole group), a quinoline group, and a quinoxaline group. Examples of the substituent of R ² include a hydrogen atom, an alkyl group (methyl group, ethyl group, butyl group, and octyl group), an alkenyl group, and an alkyne group, and a hydrogen atom is particularly preferable. X represents an anion part, and examples thereof include a halogen atom (chlorine, bromine, and iodine), p-toluenesulfonic acid, 1,5-disulfonaphthalene, boron tetrafluoride, chloric acid, and phosphorus hexafluoride. Z ¹
Is a heterocyclic ring containing a nitrogen atom, and examples thereof include an oxazole ring, a thiazole ring, a selenazole ring, an imidazole ring, a pyrrole ring, a pyridine ring, and a pyrazoline ring. Z ² represents an aromatic ring which may have a substituent, and two adjacent substituents on the aromatic ring may further form an aromatic ring or a hetero ring. The heat-decolorable dyes of the present invention are described in European Patent No. 911,693, JP-A-61-123454 and JP-A-7-33378.
The compound can be synthesized according to the dye synthesis method described in JP-A No. 4 (1993) -104.

Preferred examples of the compound of the formula (1) include the following.

[0030]

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[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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[0036]

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[0037]

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[0038]

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[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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<Base generating precursor compound of general formula (2)>
Next, the general formula (2) showing the base generating precursor compound of the present invention
Will be described in more detail.

[0045] In the formula, Z ³ and Z ⁴ are a group of atoms necessary for forming a ring of 9-membered membered 4 which may have a substituent, L ²
Represents a divalent linking group, and Y represents a substituent. n represents a positive number of 0 ≦ n ≦ 4, and when n is 2 or more, adjacent substituents may form a ring.

Preferred hetero rings of Z ³ and Z ⁴ are a pyrimidine ring, an imidazole ring, an s-triazine ring, a purine ring,
An onium compound obtained by quaternizing a nitrogen atom of a benzimidazole ring, a triazole ring, an oxazole ring, a thiazole ring, a benzothiazole ring, a benzimidazole ring, or a thiadiazole ring can be given. L ² is a divalent linking group, and the number of carbon layers which may have a substituent is 1 to 30;
Represents a saturated or unsaturated aliphatic group, an aromatic group and a heterocyclic group, specifically, an ethylene group, a propylene group,
Examples thereof include a butylene group, an isobutylene group, an octylene group, a dodecylene group, a phenylene group, a biphenylene group, a naphthylene group, and those having a substituent at these carbon atoms.
The base generating precursor compound of the present invention is disclosed in
No. 545 and Japanese Patent Publication No. 8-10321 can be synthesized.

Preferred examples of the compound of the general formula (2) include the following.

[0048]

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[0049]

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[0050]

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The general formulas (1) and (2) of the present invention
In the photosensitive layer or non-photosensitive layer of the heat-developable material of the present invention, for example, a fine particle of 1 μm or less by sand mill dispersion or jet mill dispersion, ultrasonic dispersion or homogenizer dispersion and dispersed in water or a polar solvent described below. Can be added. Many techniques are disclosed for the fine particle dispersion technique, and the average particle diameter is 0.05 μm
To 10 μm of fine particle dispersion can be added.
The fine particle dispersion preferably has a monodispersity of 1 to 30, preferably 1 to 20, which is obtained by dividing the standard deviation of the particle diameter of the dispersed fine particles by the average particle diameter and multiplying by 100. <Polymer Binder of Thermal Developing Material> As the polymeric binder of the thermal developing material of the present invention, a material which is preferable as a place where silver halide, an organic silver salt and a reducing agent react, a thermal decoloring dye is 80 to
A material that is preferable for a reaction of decoloring with heat of 200 ° C. or less or a material that allows a base generation precursor to quickly generate a base by heat is selected. Examples of the polymer binder include alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone and acetone, polymers used by dissolving in polar solvents including dimethyl sulfoxide and dimethylformamide, and water-dispersed polymers. As the polymer binder of the heat developing material of the present invention, an aqueous dispersion polymer is preferable. Further, regarding the composition of the preferred polymer, the glass transition point is more preferably from -20 ° C to 80 ° C, particularly preferably from -5 ° C to 60 ° C. This is because if the glass transition point is high, the temperature for thermal development becomes high, and if the glass transition point is low, fogging is liable to occur, resulting in a decrease in sensitivity and softness.

Examples of the polymer used by dissolving in the above-mentioned polar solvent include cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose, methylcellulose and ethylcellulose, starch and its derivatives, polyvinyl alcohol, modified polyvinyl alcohol, polyvinyl butyral, and polyacrylic acid. Sodium, polyethylene oxide, acrylamide-acrylate copolymer, styrene-maleic anhydride copolymer, polyacrylamide, sodium alginate,
Gelatin, casein, polystyrene, polyvinyl acetate,
Examples thereof include polyurethane, polyacrylic acid, polyacrylate, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, vinyl chloride-vinyl acetate copolymer, and styrene-butadiene-acryl copolymer. After drying, after forming a film, the coating film preferably has a low equilibrium water content, and particularly preferably has a low water content, such as cellulose acetate, cellulose acetate butyrate, and poly (methyl methacrylic acid). Acrylates), poly (acrylic acid), poly (methacrylic acid), poly (vinyl chloride), copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl) Acetals) (eg, poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes), phenoxy resins, poly (vinylidene chloride), poly (epoxides),
Poly (carbonate) s, poly (vinyl acetate),
Examples include cellulose esters and poly (amide) s.

As the above-mentioned water-dispersed polymer, it is preferable to use fine particles having an average particle diameter in the range of 1 nm to several μm and dispersed in an aqueous dispersion medium. Latex is particularly preferred for the water-dispersed polymer because it is widely used as a binder for aqueous coating and can improve water resistance. The amount of latex used for the purpose of obtaining water resistance as a binder is determined in consideration of coatability, but is preferably as large as possible from the viewpoint of moisture resistance.
0 mass% and 80 to 100 mass% are preferable. << Specific Examples of Latex >> Specific examples of the preferred aqueous dispersion latex are shown below. Here, styrene is St, methyl acrylate is MA, and methyl methacrylate is MM.
A, EA for ethyl acrylate, BA for butyl acrylate, INA for isononyl acrylate, CA for cyclohexyl methacrylate, HEA for hydroxyethyl acrylate, HEM for hydroxyethyl methacrylate
A, AA for acrylic acid, AAm for acrylamide, St-S for styrenesulfonic acid, AMPS for acrylamide-2-methylpropanesulfonic acid amide, IP-S for isoprenesulfonic acid, 2-propenyl-4-nonylphenoxyethylene oxide (n = 10) The sulfonic acid ester is abbreviated as PF-S, and the accompanying figures represent the mass composition ratio.

Latex example Monomer composition Molecular weight (million) Tg (1) EA97AA3 1-26 (2) EA100 2-29 (3) EA40BA57AA3 10-46 (4) EA97MMA3 13-23 (5) St20MMA30EA40BA8AA2 2038 (6) St10IP -S10MMA30EA50 2 46 (7) EA90AMPS10 5 -16 (8) MMA10EA88AMPS2 0.2 -15 (9) St30MMA20EA40BA5AA5 0.8 33 (10) CA60INA30IP-S10 3 -46 (11) MMA50EA40AMPS10 4 10 (12) MMA50EA40St-S10 10 15 (13) EA90PF-S10 50 -20 (14) MMA50EA40AAm10 20 22 (15 St20MMA30EA50HEA10 10 23 (16) St10MMA30EA50HEMA10 10 18 (17) BA40St20EA30AA10 10 11 (18) CA60INA30MA10 20 -38 (19) CA60INA30AMPS10 4 -34 (20) CA50INA30EA10AMPS10 3 -32 (21) EA95AA5 10 -25 (22) EA97BA3 13 -26 (23) EA50BA47AA3 20-36 (24) EA95MMA52-24 (25) St20MMA30EA39BA8AA3 532 (26) St15IP-S5MMA30EA50 0.233 (27) EA80AMPS20 0.823 (28) MMA2EA88AMPS10327M EA40BA5AA3 4 30 (30) CA50INA30IP-S20 10 5 (31) MMA40EA50AMPS10 50 33 (32) MMA25EA40St-S30 20 26 (33) EA80PF-S20 10 -16 (34) MMA50EA45AAm5 10 24 (35) St15MMA30EA50HEA5 10 23 (36) St10MMA35EA50HEMA5 20 33 (37) BA44St20EA30AA64-33 (38) CA64INA33MA33-36 (39) CA40INA40AMPS20 10-40 (40) CA53INA30EA10AMPS7 15-44 <Polyhalomethane compound of the general formula (3)> The polyhalomethane compound used in the present invention is the United States. Patent No. 3,874,
Compounds such as those disclosed in the specifications such as 946 and 4,756,999 can be applied. Although these polyhalomethane compounds are used as an antifoggant, the present invention greatly differs in that the presence of these compounds in a layer containing a thermal decoloring dye or in an adjacent layer promotes the decoloring property.

The general formula (3) representing the polyhalomethane of the present invention will be described in more detail. In the formula, Q represents an aromatic group or a heterocyclic group which may have a substituent, L ³ represents a divalent linking group, and X represents a halogen atom.

A benzene ring as a preferable aromatic group for Q,
Naphthalene ring, anthracene ring, florene ring, anthracene ring, azulene ring, pyridine ring as a heterocyclic group,
Phenanthroline ring, acridine ring, dibenzofuran ring, carbazole ring, quinoxaline ring, isoquinoline ring, thionaphthene ring, indole ring, benzofuran ring,
A group having a benzimidazole ring or the like can be given. X represents a halogen atom, and represents a chlorine atom, a bromine atom or an iodine atom. L ³ represents a divalent linking group, and —SO ₂
—, —SO—, and alkylene groups (such as methylene, ethylene, butylene, and acetylene). Examples of the substituent which can be introduced on the aromatic ring or hetero ring of Q include an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group) Alkenyl group (eg, vinyl group, allyl group), alkynyl group (eg, propargyl group), aryl group (eg, phenyl group), heterocyclic group (eg, pyridyl group, thiazolyl group, oxazolyl group) , Imidazolyl group, furyl group, pyrrolyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, selenazolyl group, sulfolanyl group, piperidinyl group, pyrazolyl group, tetrazolyl group, etc.), halogen atom (for example, chlorine atom, bromine atom, iodine atom, A fluorine atom), an alkoxy group (for example, a methoxy group, an ethoxy group) , Propyloxy group, pentyloxy group, cyclopentyloxy group, hexyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, Butyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, etc.), sulfonamide group (eg, methylsulfonylamino group, ethylsulfonylamino group, butylsulfonylamino group, hexylsulfonylamino group, cyclohexylsulfonylamino Group, phenylsulfonylamino group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexyl group) Aminosulfonyl group, cyclohexylaminosulfonyl group, phenylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc., ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, phenylureido group, 2-pyridyl) Ureido group, etc.), acyl group (eg, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, phenylcarbonyl group, pyridylcarbonyl group, etc.), carbamoyl group (eg, aminocarbonyl group, methylamino Carbonyl group,
Dimethylaminocarbonyl, propylaminocarbonyl, pentylaminocarbonyl, cyclohexylaminocarbonyl, phenylaminocarbonyl, 2-
Pyridylaminocarbonyl group, etc.), amide group (for example,
Methylcarbonylamino group, ethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, phenylcarbonylamino group, etc., sulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, phenylsulfonyl) Group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group,
Dimethylamino, butylamino, cyclopentylamino, anilino, 2-pyridylamino, etc.), cyano, nitro, sulfo, carboxyl, hydroxyl, oxamoyl and the like.
Further, adjacent substituents may form a condensed ring, and may further have the above substituents.

Specific examples of preferred polyhalomethane compounds are shown below.

[0058]

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[0059]

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[0060]

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[0061]

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The polyhalomethane compound of the present invention is added by dissolving it in an organic solvent or dispersing it in fine particles in water or a water-soluble solvent in the same manner as in the method of adding the compound of the formula (1) or (2). be able to. <Heat roller for heat development> The heat roller used in the heat development part of the developing machine for developing the heat development material of the present invention may be any roller having heat resistance, chemical resistance, abrasion resistance, antistatic properties and the like. However, a silicone rubber (organopolysiloxane) roller having improved heat resistance and chemical resistance is particularly preferable. Silicone rubber is colored by adding various coloring agents as needed. Carbon black and black red iron (Fe ₃ O ₄ ) are known as typical coloring agents for giving black color to silicone rubber. In addition, heat resistance is also given by adding various additives. As a method for imparting heat resistance to such a silicone rubber composition, a platinum catalyst is generally typical as a crosslinking accelerator, and a combination of a platinum catalyst with an additive such as carbon black has also been proposed. I have. For example, U.S. Pat. No. 3,652,488 mentions carbon black and U.S. Pat. No. 3,635,874 mentions titanium oxide as an auxiliary. In Japan, Japanese Patent Publication No. 51-24302 discloses iron oxide (FeO) _x (Fe ₂ O
₃ ) A method of adding _y is used. Among them, black red iron oxide (Fe ₃ O ₄ ) is described as being preferable because it is black and has excellent thermal conductivity.

However, the color of the iron oxides such as the black iron oxide changes from black to red due to an oxidation-reduction reaction between the reducing agent and the oxidizing agent in the heat developing material.
There is a problem that heat resistance tends to decrease. In the present invention, when the metal oxide added to the silicone rubber roller is an iron oxide, it is preferable that the surface thereof is subjected to a treatment for preventing deterioration.

Hereinafter, preferred examples of blending each component for producing a silicone rubber roller as a heat roller will be described. (B) 10 to 100 parts by mass of metal oxide (B), (C) with respect to 100 parts by mass of organopolysiloxane in which a part of silicon atoms may be substituted by a different atom having 1 to 30 carbon atoms.
0.1 to 10 parts by mass of a curing agent and (D) 0.1 to 50 parts by mass of iron oxides subjected to surface treatment for preventing alteration are added.

Hereinafter, the above (A), (B), (C) and (D) will be described in more detail. The organopolysiloxane of the component (A) for producing the silicone rubber roller of the present invention has a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms at the silicon atom of the organopolysiloxane, Examples of the monovalent hydrocarbon group include an alkyl group, an alkenyl group, and an aryl group. Examples of the substituent that the monovalent hydrocarbon group may have include a methyl group, a vinyl group, a phenyl group, and the like. The monovalent group selected is preferred. The alkenyl group is 0.01 to 5 mol%,
In particular, it is preferably contained in an amount of 0.02 to 0.5 mol%. Furthermore, a hydrogen atom bonded to a carbon atom such as an alkyl group, an alkenyl group, or an aryl group as the above-mentioned monovalent hydrocarbon group may be partially or entirely substituted with a halogen atom, a cyano group, or the like. , For example, 3,3,3
A trifluoropropyl group, a 2-cyanoethyl group and the like, and a 3,3,3-trifluoropropyl group is particularly preferred. Examples of both terminal groups of the molecular chain of the organopolysiloxane include a hydroxy group, a trimethylsilyl group, a dimethylvinylsilyl group, and a trivinylsilyl group, but are not particularly limited thereto. The organopolysiloxane of the component (A) has a polymerization degree of at least 2,700, preferably at least 3,000, in order to obtain sufficient mechanical strength.
20,000, particularly preferably from 4,800 to 1
It is 0000. As the organopolysiloxane (A), two or more kinds having different structures and degrees of polymerization can be used in combination.

The metal oxide (B) is used to reinforce silicone rubber, and examples thereof include silica, alumina, titanium oxide, magnetite, hematite, and black bengalara. Particularly preferred is silica. Although in order to improve the mechanical strength of and such that tensile strength gives the hardness of moderate to silicone rubber, the specific surface area having its used is not less than 66m ² / g, in particular 99m ² ~444m ² / g are preferred. As such a reinforcing silica, specifically, fumed silica, calcined silica, precipitated silica, or the like is used alone or in combination of two or more. These silicas may be surface-treated with a linear organopolysiloxane, a cyclic organopolysiloxane, hexamethyldisilazane, dichlorodimethylsilane, or the like. The compounding amount of the component (B) is 10 to 100 parts by mass, preferably 20 to 100 parts by mass, per 100 parts by mass of the organopolysiloxane of the component (A).
50 parts by mass. If the compounding amount is out of this numerical range,
In some cases, the processability of the silicone rubber composition may deteriorate, or sufficient mechanical strength may not be obtained.

The component (C) cures the composition of the present invention into a silicone rubber, and generally uses an organic peroxide. When the organopolysiloxane of the component (A) contains two or more alkenyl groups in the molecule, a combination of an organohydrogenpolysiloxane and a platinum-based catalyst can be used as a curing agent.
The amount of the curing agent may be an amount sufficient to cure the composition of the present invention as described below. Examples of the organic peroxide that can be used in the present invention include dicumyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, and 2,5-dimethyl-2,5-di (t-butylperoxy). Hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-dimethyl-2,
5-di (t-butylperoxy) 3,3,5-trimethylcyclohexane, benzoyl peroxide, 2,4
-Dichlorobenzoyl peroxide, 4-chlorobenzoyl peroxide and the like. The compounding amount of these organic peroxides is 0.1 to 1 based on 100 parts by mass of the component (A) as an amount sufficient to cure the composition of the present invention.
It is within the range of 0 parts by mass.

When the organopolysiloxane of the component (A) contains two or more alkenyl groups in the molecule, the organohydrogenpolysiloxane that can be used as a curing agent includes a methyl group-blocked trimethylsiloxy group at both ends. Examples thereof include hydrogen polysiloxane, a dimethyl siloxane / methyl hydrogen siloxane copolymer having a trimethylsiloxy group at both terminals, and a dimethyl siloxane / methyl hydrogen siloxane copolymer having a methyl hydrogen siloxy group at both terminals. On the other hand, examples of the platinum catalyst include chloroplatinic acid, an alcohol solution of chloroplatinic acid, and a complex of chloroplatinic acid and divinyltetramethylsiloxane. The amount of the above-mentioned organohydrogenpolysiloxane is generally such that the ratio of the number of moles of hydrogen atoms bonded to silicon atoms contained in the organohydrogenpolysiloxane to the number of moles of alkenyl groups in the component (A) is ( 0.5: 1) to (20: 1), and the amount of the platinum-based catalyst is generally about 0.1 to 3,000 ppm in terms of platinum based on the mass of the component (A). When a platinum compound is used as the heat-resistant agent, it can be used in common.

Next, component (D) is a preferred component of the silicone composition. Magnetite, hematite, surface-treated with a metal oxide such as alumina, silica, silica-alumina, titanium oxide, tin oxide, etc. 0.1 to 50% by mass of iron oxides such as black red iron oxides or magnetite, hematite, black red iron oxides and the like, which are subjected to a deterioration preventing treatment by doping the surface with a metal such as manganese, antimony, tin, and zinc. Contained.

Particularly preferred components of the silicone composition of the present invention include magnetite treated with 1 to 10% by mass of alumina or silica-alumina and / or 10 to 20% by mass.
Hematite in the form of fine powder doped with manganese by mass%. In general, when magnetite or hematite is in contact with an oxidizing agent, the surface is oxidized and changes color from black to red when 80 ° C. is exceeded, and magnetite or hematite surface-treated as described above has excellent heat resistance, It does not cause browning or redness in the heat resistance test and chemical resistance of the silicone rubber roller obtained from the silicone composition containing these compounds, and furthermore shows excellent heat resistance when used in combination with a platinum compound, and after exposure to high temperatures The characteristic that the decrease in mechanical strength is small is exhibited. As described above, the treatment amount of alumina or silica-alumina is 1 to 10 with respect to magnetite.
If the amount is less than 1% by mass, sufficient heat resistance cannot be imparted to the silicone rubber roller, so that 10% by mass
If it exceeds 3, sufficient dispersibility of the surface-treated magnetite cannot be obtained, and a silicone rubber roller having a uniform mechanical strength cannot be obtained.

Hematite is usually red, but finely powdered hematite doped with 10 to 20% by mass of manganese as described above becomes excellent black. If it does not give a sufficient black color and exceeds 20% by mass, hematite tends to agglomerate and the dispersibility decreases. The surface treatment can be performed using commercially available manganese or hematite.

The component (D) is further treated with an organic compound such as a silane coupling agent or an inorganic compound such as Al or Si to the extent that the object of the present invention is not impaired, thereby improving fluidity and chemical resistance. Things can also be used. (D)
The particle size of the component is preferably from 0.1 to 5.0 μm, more preferably from 0.1 to 2.0 μm. Those having a particle size of less than 0.1 μm have high activity and may be difficult to be blended.
If it exceeds m, the mechanical strength of the cured product may be impaired. In the present invention, a kneader, such as a kneader, a Banbury mixer, or an open roll, which is usually used when compounding the component (D) with the organopolysiloxane composition, can be used. As described above, the compounding amount of the component (D) is preferably 0.1 to 50 parts by mass, more preferably 0.5 to 5 parts by mass based on 100 parts by mass of the organopolysiloxane of the component (A). Can be If the amount is less than 0.1 part by mass, the black color will not be sufficient, and the heat resistance and chemical resistance will be insufficient.
If the amount is more than 10 parts by mass, the elasticity of the silicone rubber roller deteriorates. Further, two or more kinds of the component (D) may be used in combination.

The above-mentioned platinum compound synergistically improves the heat resistance effect of the silicone rubber together with the component (D), and may be in the form of chloroplatinic acid or an alcohol solution of chloroplatinic acid as described above. No. The amount of the platinum compound is 0.0001 to 0.1 part by mass, preferably 0.001 to 0.01 part by mass, based on 100 parts by mass of the silicone rubber composition of the present invention in terms of platinum. If the value is less than the lower limit of the limited range, the effect becomes insufficient, and if the value exceeds the upper limit of the limited range, the effect is not changed, and it is not economical.

The silicone rubber composition may contain, in addition to the components (A) to (D), various rubber compounding agents which are usually appropriately compounded in the silicone rubber in amounts which do not impair the object of the present invention. For example, diphenylsilanediol, low polymerization degree silicone oil having a molecular chain terminal hydroxyl group, hexamethyldisilazane, dispersant such as alkoxysilane, pulverized silica, diatomaceous earth, zinc oxide, titanium oxide, carbon black, barium oxide, carbonic acid Calcium, magnesium carbonate, zinc carbonate, asbestos, glass wool, fine mica, fused silica powder and the like may be added and blended. Further, if necessary, an antioxidant, an antioxidant, an antistatic agent, a thermal conductivity improver such as boron nitride and aluminum oxide may be blended.

The method for producing the silicone rubber composition is not particularly limited, but the components (A) and (B) are charged into a kneading device such as a kneader and blended at room temperature.
A method in which heat treatment is performed at a temperature of 200 ° C. for 30 minutes to 5 hours, and then the component (D) is added and kneaded with a roller mill, a Banbury mixer, or the like can be employed. After that, the component (C) may be added, and then heat-cured by a known method.
The cured silicone rubber thus obtained has good heat resistance and chemical resistance. <Organic silver salt contained in the heat-developable material of the present invention> The organic silver salt contained in the heat-developable material of the present invention is a reducible silver source. Silver salts of organic acids and acid polymers are used. Also useful are organic or inorganic silver salt complexes in which the ligand has a total stability constant for silver ions of 4.0 to 10.0. Examples of silver salts are Research Disclosure No. 1
7029 and 29996, and include the following: salts of organic acids (eg, salts of gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, lauric acid, etc.); carboxyalkylthiourea salts of silver (For example, 1
-(3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc.);
Silver complexes of polymer reaction products of aldehydes and hydroxy-substituted aromatic carboxylic acids (eg, formaldehyde,
Aldehydes such as acetaldehyde and butyraldehyde and hydroxy-substituted acids such as salicylic acid, benzylic acid 3,5-dihydroxybenzoic acid and 5,5-thiodisalicylic acid); silver salts or complexes of thioenes (for example, 3-
(2-carboxyethyl) -4-hydroxymethyl-4
-Thiazoline-2-thioene and 3-carboxymethyl-4-methyl-4-thiazoline-2-thioene); imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole, 3-amino-5-benzylthio Complexes and salts of silver and a nitrogen acid selected from -1,2,4-triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides. <Reducing Agent Contained in Thermal Development Material of the Present Invention> The thermal development material of the present invention preferably contains a reducing agent. Examples of suitable reducing agents are described in U.S. Patent Nos. 3,770,448, 3,773,512, 3,593,863, and the like, and Research Disclosure.
Nos. 17029 and 29996, and include the following.

Aminohydroxycycloalkenone compounds (eg, 2-hydroxy-3-piperidino-2-cyclohexenone); aminoreductone esters (eg, piperidinohexose reductone monoacetate) as precursors of the reducing agent; Hydroxyurea derivatives (eg, Np-methylphenyl-N-hydroxyurea);
Aldehyde or ketone hydrazones (e.g., anthracene aldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (e.g., hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5- Dihydroxy-phenyl) methylsulfone); sulfhydroxamic acids (eg, benzenesulfhydroxamic acid); sulfonamidoanilines (eg, 4- (N-methanesulfonamido) aniline);
-Tetrazolylthiohydroquinones (e.g., 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (e.g.,
1,2,3,4-tetrahydroquinoxaline); amide oximes; azines; a combination of aliphatic carboxylic acid arylhydrazides and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine; reductone and / or hydrazine; A combination of azines and sulfonamidophenols;
Cyanophenylacetic acid derivative; combination of bis-β-naphthol and 1,3-dihydroxybenzene derivative;
-Pyrazolones; sulfonamidophenol reducing agent; 2
-Phenylindane-1,3-dione and the like; chroman;
1,4-dihydropyridines (for example, 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine); bisphenols (for example, bis (2-hydroxy-3-t-butyl-5-methyl) Phenyl) methane, bis (6-hydroxy-m-tri) mesitol (m
esitol), 2,2-bis (4-hydroxy-3-
Methylphenyl) propane, 4,4-ethylidene-bis (2-t-butyl-6-methylphenol), ultraviolet-sensitive ascorbic acid derivative; hindered phenols;
3-pyrazolidones. Among them, particularly preferred reducing agents are hindered phenols. Examples of the hindered phenols include compounds represented by the following general formula (A).

[0077]

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In the formula, R is a hydrogen atom or a group having 1 to 1 carbon atoms.
10 alkyl group (e.g., -C ₄ H _9, 2,4,4-trimethyl pentyl) represents, R 'and R "is an alkyl group having 1 to 5 carbon atoms (e.g., methyl, ethyl, t- butyl ).

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

[0080]

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[0081]

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The amount of the reducing agent including the compound represented by formula (A) is preferably 1 × per mole of silver.
It is 10 ^-2 to 10 mol, especially 1 × 10 ^{-2 to} 1.5 mol. <Photosensitive silver halide contained in the heat-developable material of the present invention> The photosensitive silver halide contained in the photosensitive layer of the heat-developable material of the present invention is used in the field of photographic technology such as a single jet or double jet method. Prepared in advance by any method such as an ammonia method emulsion, a neutral method, an acid method, and the like, and then mixed with other components of the present invention and introduced into a composition used in the present invention. can do. In this case, in order to sufficiently contact the photosensitive silver halide with the organic silver salt, for example, US Pat.
No. 564, No. 3,706,565, No. 3,71
No. 3,833,3,748,143 and British Patent No. 1,362,970. Means using a polymer other than gelatin, such as polyvinyl acetals, and British Patent No. 1,354. Means for Enzymatically Degrading the Gelatin of a Light-Sensitive Silver Halide Emulsion as described in U.S. Pat. No. 4,186,539, or as described in US Pat. No. 4,076,539. By preparing the particles in the presence of a surfactant, various means such as a means for omitting the use of the protective polymer can be applied.

The photosensitive silver halide functions as an optical sensor, and preferably has a small grain size in order to suppress white turbidity after image formation and to obtain good image quality. 0.1 μm or less in average particle size, preferably 0.01 to 0.1 μm, particularly 0.02 to 0.0
8 μm is preferred. The shape of the silver halide is not particularly limited, and may be cubic, octahedral, so-called normal crystals, or non-normal crystals, such as spherical, rod-like, or tabular grains. The silver halide composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide, and silver iodide.

The amount of the silver halide is 50% by mass or less, preferably 25 to 0.1% by mass, more preferably 15 to 0.1% by mass, based on the total amount of the silver halide and the organic silver salt described below. is there.

The photosensitive silver halide used in the photothermographic material of the present invention is also disclosed in British Patent No. 1,447,454.
As described in the specification, when an organic silver salt is prepared, a halogen component such as a halide ion is made to coexist with an organic silver salt-forming component, and silver ions are injected into the organic silver salt to form an organic silver salt. They can be generated almost simultaneously.

As still another method, a silver halide forming component is allowed to act on a solution or dispersion of an organic silver salt prepared in advance or a sheet material containing the organic silver salt to expose a part of the organic silver salt to light. It can also be converted to neutral silver halide. The silver halide thus formed is in effective contact with the organic silver salt and exhibits a preferable action. A silver halide-forming component is a compound capable of forming a photosensitive silver halide by reacting with an organic silver salt, and which compound is applicable and effective is determined by the following simple test. I can do things. That is, an organic silver salt is mixed with a compound to be tested, and if necessary, after heating, it is examined by an X-ray diffraction method whether there is a peak specific to silver halide.
Silver halide-forming components confirmed to be effective by such tests include inorganic halides, onium halides, halogenated hydrocarbons, N-halogen compounds, and other halogen-containing compounds. Are U.S. Pat. Nos. 4,009,039 and 3,4
57,075, 4,003,749, British Patent 1,498,956, etc.
Nos. 27027, 53-25420, etc., are described in detail, examples of which are shown below.

[0087] generated in (1) above silver halide when inorganic halide is used: for example, halide (wherein M represented by MX _n, represents H, NH _4, and a metal atom, X is a halogen N represents M and H and NH ₄
Represents 1 when １ is a metal atom, and represents its valence when M is a metal atom. As the metal atom, lithium, sodium, potassium, cesium, magnesium, calcium, strontium,
Barium, zinc, cadmium, mercury, tin, antimony,
Chromium, manganese, iron, cobalt, nickel, rhodium, cerium, etc.) are used, and halogen molecules such as bromine water are also effective. (2) When onium halides are used: for example, quaternary ammonium halides such as trimethylphenylammonium bromide, cetylethyldimethylammonium bromide, and trimethylbenzylammonium bromide; and quaternary phosphoniums such as tetraethylphosphonium bromide. Halides and tertiary sulfonium halides such as trimethylsulfonium iodide are used. (3) When halogenated hydrocarbons are used: For example, iodoform, bromoform, carbon tetrachloride, 2-bromo-2-methylpropane and the like are used. (4) When an N-halogen compound is used: For example, N
-Chlorosuccinimide, N-bromosuccinimide, N-
Bromphthalimide, N-bromoacetamide, N-iodosuccinimide, N-bromophthalazone, N-bromooxazolinone, N-chlorophthalazone, N-bromoacetanilide, N, N-dibromobenzenesulfonamide, N-bromo-N- Methylbenzenesulfonamide,
1,3-dibromo-4,4-dimethylhydantoin, N
-Bromourazole and the like are used. (5) When other halogen-containing compounds are used:
For example, triphenylmethyl chloride, triphenylmethyl bromide, 2-bromoacetic acid, 2-bromoethanol, dichlorobenzophenone and the like are used.

These silver halide forming components are used in a small amount stoichiometrically with respect to the organic silver salt. Usually, the range is from 0.001 mol to 0.7 mol, preferably from 0.03 mol to 0.5 mol, per 1 mol of the organic silver salt. Two or more silver halide forming components may be used in combination within the above range. Various conditions such as a reaction temperature, a reaction time, and a reaction pressure in the step of converting a part of the organic silver salt into silver halide using the above-mentioned silver halide forming component can be appropriately set according to the purpose of production. Usually, the reaction temperature is −23 ° C. to 74 ° C., the reaction time is 0.1 second to 72 hours, and the reaction pressure is preferably set to the atmospheric pressure.
This reaction is also preferably performed in the presence of the polymer used as the binder. The amount of the polymer used at this time is 0.01 to 100 parts by mass, preferably 0.1 to 10 parts by mass per 1 part by mass of the organic silver salt.

The photosensitive silver halide prepared by the various methods described above includes, for example, sulfur-containing compounds, gold compounds,
Platinum compounds, palladium compounds, silver compounds, tin compounds,
Chemical sensitization can be performed by a chromium compound or a combination thereof. The method and procedure of this chemical sensitization are described in, for example, U.S. Pat. No. 4,036,650, British Patent No. 1,518,850, and the like.
No. 22430, No. 51-78319, No. 51-811
No. 24 and other publications. Further, when a part of the organic silver salt is converted into a photosensitive silver halide by a silver halide forming component, as described in US Pat. No. 3,980,482, sensitization is achieved. A low molecular weight amide compound may coexist.

In addition, these photosensitive silver halides may be used in order to prevent illuminance failure or to adjust the gradation.
Metals belonging to Group 0, such as Rh, Ru, Re, Ir, O
An ion such as s or Fe, a complex thereof, or a complex ion can be contained. It is particularly preferable to contain ions or complex ions of metals belonging to Groups 6 to 10 of the periodic table. As the above metals, W, Fe, Co, Ni,
Cu, Ru, Rh, Pd, Re, Os, Ir, Pt, A
u is preferable, and when it is used for a photosensitive material for plate making, it is preferably selected from Rh, Re, Ru, Ir, and Os.

These metals can be introduced into the silver halide in the form of a complex. In the present invention, the transition metal complex is preferably a six-coordinate complex represented by the following general formula.

Formula: [ML ₆ ] ^{m In the} formula, M is a transition metal selected from Group 6 to 10 elements of the periodic table, L is a bridging ligand, and m is 0, 1-, 2- or 3
Represents-. Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and aquo. Ligand, nitrosyl, thionitrosyl and the like, preferably aquo, nitrosyl and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands. A plurality of L may be the same or different. Particularly preferred specific examples of M include rhodium (Rh), ruthenium (Ru), and rhenium (Re).
And osmium (Os).

The content of metal ions or complex ions is generally 1 × 10 ^-9 per mol of silver halide.
~ 1 × 10 ^-2 mol is suitable, preferably 1 × 10 ^-8 mol.
１1 × 10 ^-4 mol. The compound that provides the ion or complex ion of these metals is preferably added during silver halide grain formation and incorporated into the silver halide grains. Preparation of silver halide grains, that is, nucleation, growth, and physical ripening It may be added at any stage before and after chemical sensitization, but is particularly preferably added at the stage of nucleation, growth, and physical ripening, more preferably at the stage of nucleation and growth. Preferably, it is added at the stage of nucleation.
In the addition, it may be added in several portions, may be added uniformly in the silver halide grains, or may be added to the silver halide grains as described in JP-A-63-29603 and JP-A-2-3062.
No. 36, No. 3-167545, No. 4-76534,
As described in JP-A-6-110146, JP-A-5-273683, and the like, the particles can be contained in the particles with a distribution. Preferably, a distribution can be provided inside the particles. These metal compounds can be added by dissolving them in water or a suitable organic solvent (eg, alcohols, ethers, glycols, ketones, esters, amides). A method in which an aqueous solution or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble silver salt solution or a water-soluble halide solution during grain formation, or a silver salt solution and a halide solution are mixed at the same time. To prepare silver halide grains by a method of simultaneous mixing of three liquids, a method of charging a required amount of an aqueous solution of a metal compound into a reaction vessel during grain formation, or a method of preparing silver halide. There is a method in which another silver halide grain doped with a metal ion or a complex ion in advance is sometimes added and dissolved. In particular, a method of adding an aqueous solution of a powder of a metal compound or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble halide solution. When adding to the particle surface, a required amount of an aqueous solution of a metal compound can be charged into the reaction vessel immediately after the formation of the particles, during or at the end of physical ripening, or at the time of chemical ripening. <Matting agent> In the present invention, the protective layer on the photosensitive layer or B
It is preferable that a matting agent is contained in the C layer, the protective layer on the BC layer, and the like, and the material of the matting agent used in the present invention may be either an organic substance or an inorganic substance. For example, inorganic substances include silica described in Swiss Patent No. 330,158, glass powder described in French Patent No. 1,296,995, etc., and alkali described in British Patent No. 1,173,181 and the like. An earth metal or a carbonate such as cadmium or zinc can be used as a matting agent. Examples of organic substances include starch described in U.S. Pat. No. 2,322,037, starch derivatives described in Belgian Patent No. 625,451 and British Patent No. 981,198, and Japanese Patent Publication No. 44-3643. Polyvinyl alcohol, Swiss Patent 330,
An organic matting agent such as polystyrene or polymethacrylate described in U.S. Pat. No. 158, etc., polyacrylonitrile described in U.S. Pat. No. 3,079,257, and polycarbonate described in U.S. Pat. No. 3,022,169 is used. Can be used.

The shape of the matting agent may be either regular or irregular, but is preferably regular and spherical. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. In the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere.
The matting agent used in the present invention has an average particle size of 0.5 to 1
0 μm, more preferably 1.0 to
It is 8.0 μm. Further, a matting agent having a particle monodispersity of preferably 50 or less, more preferably 40 or less, and particularly preferably 20 or less. here,
The monodispersity of the particles is represented by a number obtained by dividing the standard deviation of the particle size by the average value of the particle size and multiplying by 100. The method for adding the matting agent according to the present invention may be a method in which the matting agent is dispersed in advance and applied, or a method in which the matting agent is sprayed before the drying is completed after applying the coating liquid. You may.
When a plurality of types of matting agents are added, both methods may be used in combination.

The heat-developable material of the present invention forms a photographic image by a heat-development process. In addition to silver and the like, it is preferable that a hydrazine compound and a color-toning agent for suppressing color tone are contained in the binder in a dispersed state, if necessary. The heat developing material of the present invention is stable at normal temperature, but is developed by heating to a high temperature (for example, 80 ° C. to 200 ° C.) after exposure. Heating generates silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. The silver produced by the reaction of the organic silver salt in the exposed areas provides a black image and the image is formed in contrast to the unexposed areas. This reaction process proceeds without supplying a processing liquid such as water from the outside. <Hydrazine compound> The heat-developable material of the present invention contains a hydrazine compound as a high contrast agent for enhancing the contrast of a silver image. Examples of the hydrazine compound include compounds H-1 to H-29 described in columns 11 to 20 of US Pat. No. 5,545,505 and columns 9 to 29 of US Pat. No. 5,464,738. Compounds described in Compounds 1 to 12 described in 11 are preferably used. These hydrazine compounds can be synthesized by a known method.

The hydrazine compound is added to the photosensitive layer and / or a layer adjacent to the photosensitive layer, and the amount of addition is uniform depending on the particle size of silver halide grains, halogen composition, degree of chemical sensitization, type of inhibitor, and the like. However, the range is preferably about 10 ^-6 to 10 ^-1 mol, more preferably 10 ^-5 to 10 ^-2 mol per mol of silver halide. <Tone> It is preferable to add a tone to the photothermographic material of the present invention. Examples of suitable toning agents are Research
ch Disclosure No. 17029, which includes:

Imides (eg, phthalimide); cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and , 4-thiazolidinedione); naphthalimides (eg, N-hydroxy-1,8-naphthalimide); cobalt complexes (eg, hexamine trifluoroacetate of cobalt); mercaptans (eg, 3
-Mercapto-1,2,4-triazole); N- (aminomethyl) aryldicarboximides (for example,
N- (dimethylaminomethyl) phthalimide); blocked pyrazoles, isothiuronium (isoth
uronium) derivatives and certain photobleaches (eg, N, N'-hexamethylene (1-carbamoyl-3,5-dimethylpyrazole), 1,8-
A combination of (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) benzothiazole; a merocyanine dye (e.g., 3-ethyl-5-((3-ethyl -2-benzothiazolinylidene (benzothiazolinylidene))-1-methylethylidene) -2-thio-2,4
Oxazolidinedione); phthalazinone, a phthalazinone derivative or a metal salt of these derivatives (for example, 4-
(1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethyloxyphthalazinone, and 2,3
-Dihydro-1,4-polyhalomethane compound dione);
Combination of phthalazinone and sulfinic acid derivative (for example, 6-chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); combination of polyhalomethane compound + phthalic acid; polyhalomethane compound (addition of polyhalomethane compound) And maleic anhydride, and phthalic acid, 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivatives and anhydrides thereof (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic acid) Acid anhydrides); quinazolinediones, benzoxazines, naltoxazine derivatives; benzoxazine-2,4
-Diones (for example, 1,3-benzoxazine-2,
4-dione); pyrimidines and asymmetric-triazines (e.g., 2,4-dihydroxypyrimidine), and tetraazapentalene derivatives (e.g., 3,6-dimercapto-1,4-diphenyl-1H, 4H-2) , 3a,
5,6a-tetraazapentalene). <Sensitizing dyes> The photothermographic materials of the present invention include, for example, JP-A-63-159814, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651 and JP-A-6-259561.
JP-A-3-304242, JP-A-63-15245 and the like; U.S. Pat. Nos. 4,639,414 and 4,74
No. 0,455, No. 4,741,966, No. 4,7
Sensitizing dyes described in each specification such as No. 51,175 and No. 4,835,096 can be used. Useful sensitizing dyes for use in the present invention include, for example, Research Disc
Lost Item 17643 IV-A (1978
December, p. 23), Item 1831X (197)
August 2008 p. 437) or in the literature cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected. For example, JP-A-9-34078 and JP-A-9-54
Compounds described in JP-A Nos. 409 and 9-80679 are preferably used. <Support> As the support, a support such as paper, synthetic paper, nonwoven fabric, metal foil, or plastic film can be used, and a composite sheet obtained by combining these can be used arbitrarily. <Image exposure> In the present invention, for example, exposure is performed at an emission wavelength of 660 nm, 670 nm, 780 nm, 810 nm,
It is preferably performed by any one of 830 nm laser scanning exposure, but it is preferable to use a laser scanning exposure machine in which the angle between the exposure surface of the heat developing material and the scanning laser beam does not become substantially perpendicular. Here, "not substantially vertical" means that the laser scanning angle is preferably 55 to 88 degrees, more preferably 60 to 86 degrees, still more preferably 65 to 84 degrees, and most preferably 70 to 82 degrees. It means that. When the laser beam is scanned on the heat developing material, the beam spot diameter on the heat developing material exposed surface is
Preferably 200 μm or less, more preferably 100 μm
It is as follows. It is preferable that the spot diameter is small in that the shift angle of the laser incident angle from the perpendicular can be reduced. Note that the lower limit of the beam spot diameter is 10 μm. By performing such laser scanning exposure, it is possible to reduce image quality deterioration related to reflected light such as occurrence of unevenness like interference fringes.

It is also preferable that the exposure in the present invention is performed using a laser scanning exposure machine which emits a scanning laser beam which is a vertical multi. By using vertical multi-mode laser exposure, image quality deterioration such as occurrence of interference fringe-like unevenness is reduced as compared with vertical single-mode scanning laser light. In addition to the above-described method, there is a method of vertical multiplexing, such as combining, using return light, or applying high frequency superposition. In addition, the vertical multi means that the exposure wavelength is not single, and the distribution of the exposure wavelength is usually 5 nm or more, preferably 10 nm or more.
nm or more. The upper limit of the exposure wavelength distribution is not particularly limited, but is usually about 60 nm. <Developing Method> FIG. 1 is a cross-sectional view of an essential part showing an example of a heat developing apparatus for explaining a developing method of the present invention. It is introduced into the developing unit 7 by the transport roller 2 with
The developer is heated and conveyed by the developing unit 7 to be developed, and is discharged by the discharge roller 4. The developing unit 7 has a heat source 3 such as a far-infrared heater or a nichrome wire heater, and a heat drum 5 rotating in the direction of an arrow.
Is conveyed between a plurality of heat roller groups 6 that rotate in synchronization with the heat roller group 6. Reference numerals 8 and 8 'denote heat insulating covers, and the rear surface of the heat insulating cover 8 is a cold mirror for reflecting heat. A preheating means (not shown) is provided before introducing the heat developing material 1 into the developing unit 7, and after the heat developing material 1 is developed,
It is preferable to provide a cooling means (not shown).

Here, the heat drum 5 is made of copper, aluminum,
A material having excellent thermal conductivity such as steel is used, and the plurality of heat roller groups 6 are preferably silicone rollers containing iron oxides surface-treated with the above-described metal or metal oxide. It is preferable that the surface hardness is 1 × 10 ⁻⁴ to 1 Pa when expressed as an elastic modulus. The transport speed of the heat developing material 1 is 1 to 100 cm / sec.
Preferably at 80 to 180 ° C. for 5 to 100 sec.
It is preferable to carry out development by heating and transporting for c. The pressure between the heat drum 5 and the heat roller group 6 during transport is preferably 10 ² to 10 ⁵ Pa.

In the above description, no heat source is provided on the heat roller group 6 side, and the heat roller group 6 is pressed against the heat drum 5 having a built-in heat source, and is heated by heat reflection of a cold mirror on the inner surface of the heat insulating cover 8. In the developing method of the present invention, a heat source may be provided in the heat roller group 6 to perform development.

[0101]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 [Preparation of Thermal Developing Material as Sample] <Preparation of Subbed Support> A polyethylene terephthalate support having a thickness of 175 μm was subjected to a corona discharge treatment of 8 w / m ² · min. Is coated with the following undercoating solution a-1 so as to have a dry film thickness of 0.8 μm and dried to form an undercoating layer A-1, and the other undercoating solution b-1 is coated on the opposite surface.
Was applied to a dry film thickness of 0.8 μm and dried to obtain an undercoat layer B-1. << Undercoating coating liquid a-1 >> Copolymer latex liquid of butyl acrylate (30% by mass), t-butyl acrylate (20% by mass), styrene (25% by mass), and 2-hydroxyethyl acrylate (25% by mass) (Solid content 30%) 270 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Finished to 1 liter with water. << Undercoat Coating Solution b-1 >> Copolymer latex liquid of butyl acrylate (40% by mass), styrene (20% by mass), and glycidyl acrylate (40% by mass) (solid content: 30%) 270 g hexamethylene-1,6 -Bis (ethylene urea) 0.8 g Finished to 1 liter with water.

Subsequently, the undercoat layer A-1 and the undercoat layer B-1
A corona discharge of 8 W / m ² · min is applied to the upper surface of the lower layer, and the lower layer upper layer coating solution a-2 shown below is coated and dried on the lower layer A-1 so as to have a dry film thickness of 0.1 μm. A-2
Is provided on the undercoat layer B-1.
2 was applied and dried so as to have a dry film thickness of 0.8 μm to provide an undercoating upper layer B-2 having an antistatic function. << Coating solution a-2 for lower undercoat >> Gelatin Mass of 0.4 g / m ² Silica particles (average particle size: 3 μm) 0.1 g Finished to 1 liter with water. << Undercoating upper layer coating solution b-2 >> Styrene butadiene copolymer latex solution (solid content 20%) 80 g Polyethylene glycol (weight average molecular weight 600) 6 g Finished to 1 liter with water. << Preparation of Silver Halide Emulsion A >> 7.5 g of inert gelatin and 10 mg of potassium bromide were dissolved in 900 ml of water, and the temperature was adjusted to 35 ° C. and the pH to 3.0.
g of an aqueous solution containing 370 ml of an aqueous solution containing potassium bromide and potassium iodide (equimolar amount to silver nitrate) in a molar ratio of (98/2) over 10 minutes by a controlled double jet method while maintaining a pAg of 7.7. did. Thereafter, 0.3 g of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added, the pH was adjusted to 5 with NaOH, the average particle size was 0.06 μm, and the variation coefficient of the projected diameter area was 8%. Thus, cubic silver iodobromide grains having a [100] face ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, desalting treatment, and then 0.1 g of phenoxyethanol was added.
5.9 and pAg 7.5, and adjusted to silver halide emulsion A.
I got << Preparation of Water-Dispersed Organic Silver Salt >> 111.4 g of behenic acid, 83.8 g of arachidic acid and 54.9 g of stearic acid were dissolved in 4720 ml of pure water at 80 ° C. Next, while stirring at a high speed, 540.2 m of a 1.5 mol sodium hydroxide aqueous solution
After adding 6.9 ml of concentrated nitric acid, the mixture was cooled to 55 ° C. to obtain a sodium organic acid solution. While maintaining the temperature of the organic acid sodium acid solution at 55 ° C., the silver halide emulsion A (containing 0.038 mol of silver) and 450 ml of pure water
Was added and stirred for 5 minutes. Next, a 1 molar silver nitrate solution 76
0.6 ml was added over 2 minutes, stirred for another 20 minutes, and the water-soluble salts were removed by filtration. Thereafter, washing with deionized water and filtration were repeated until the conductivity of the filtrate reached 2 μS / cm, and water was added to a predetermined concentration to finish. <Coating of photosensitive layer and non-photosensitive layer> The following layers were sequentially formed on a support provided with the undercoat layer to prepare a sample. In addition, each drying was performed at 75 degreeC for 1 minute. << BC Layer Coating >> On the back surface side, a coating solution prepared by further adding water to the following aqueous solution or water dispersion of the thermal decoloring dye composition is applied and dried so as to have the following coating amount to form a BC layer. Formed.

Polyvinyl alcohol 2.0 g / m ² 12 types of thermal decoloring dyes shown in Table 1 (including comparative dyes AHD1 to AHD4) 2.3 × 10 ⁻⁵ mol / m ²

[0105]

Embedded image

<< Coating of BC Layer Protective Layer >> Inert Gelatin 0.8 g / m^Two Matting agent (PMMA: average particle size 3μ) 0.02 g / m^Two Activator: N-propyloctylsulfonamidoacetic acid 0.02 g / m^Two Hardener: 1,2-bisvinylsulfonamidoethane 0.02 g / m^Two << Coating of photosensitive layer >> Moisture of the following composition for forming the photosensitive layer
The powder was added to water to prepare a coating solution. Apply this coating solution to 35
℃, silver electrode (purity 99.99% or more) and 10
% KNO _ThreeIn a 3 molar solution through a salt bridge consisting of a salt solution
Silver formed from a reference electrode consisting of an Ag / AgCl electrode
Measure the silver potential using an electrometer, and then
The resultant was coated and dried to form a photosensitive layer.

The above aqueous dispersion of the prepared organic silver salt was mixed with a binder in an amount of 1.4 g / m ² in terms of silver.

In the above adjustment liquid, the content of silver halide was 1/10 equivalent to the organic silver salt.

Binder: Styrene-butadiene latex 5.6 g / m ² sensitizing dye-1: DyeA 8 mg / m ² sensitizing dye-2: DyeB 10 mg / m ² Antifoggant-1: pyridinium hydrobromide perbromide 3 mg / m ² antifoggant -2: isothiazolone 1.2 mg / m ² antifoggant -3: 2-tribromomethylsulfonyl quinoline 120 mg / m ² reducing agent: example compound A-4 3.3 mmol / m ² photosensitive The pH of the layer coating solution was adjusted to 5.6.

[0110]

Embedded image

<< Coating of Surface Protective Layer >> A coating solution prepared by adding the following composition was applied and dried so as to have the following amount to form a surface protective layer, and a sample for comparison shown in Table 1 was prepared. 1
-1 to 1-4 and 1 of Samples 1-5 to 1-12 for the present invention
Two samples were obtained.

Inert gelatin 1.2 g / m ² 4-methylphthalic acid 0.7 g / m ² Tetrachlorophthalic acid 0.2 g / m ² Tetrachlorophthalic anhydride 0.5 g / m ² Silica matting agent (average particle size) 5 μm) 0.5 g / m ² 1,2- (bisvinylsulfone acetamide) ethane 0.3 g / m ² [Evaluation of photographic performance] The above 12 kinds of samples were used as a normal humidity test sample and a high humidity test sample. Each sample was exposed with a semiconductor laser or a gas laser sensitometer, and then developed at 120 ° C. for 8 seconds using a thermal developing apparatus having the structure shown in FIG. In the above normal humidity test, 25
After placing in an atmosphere of 60 ° C. and 60% RH for 3 days, laser exposure and heat development were performed. In the high-humidity test, 60 pieces (5 × 1) of the same sample number were used for each of the sample pieces after coating and drying in an atmosphere of 35 ° C. and 78% RH.
2) After overlapping and storing for 3 days by applying a pressure of 4.9 kPa to the upper part, the central part of the same five consecutive sheets was taken out, and laser exposure and thermal development were performed in the same manner as above. For exposure, a laser beam near the maximum absorption of the dye was used. Laser exposure is 630nm, 660nm, 7
A laser that generates light of each wavelength of 30 nm, 780 nm, 810 nm, and 830 nm is appropriately selected according to the absorption wavelength of the sample to be used. At that time, exposure and development are 25
The test was performed in a room conditioned at 54 ° C. and a relative humidity of 54%. The evaluation (sensitivity and fog) of the obtained image was measured with a densitometer.
The sensitivity was evaluated by the reciprocal of the ratio of the exposure amount giving a density 0.3 higher than the fog (minimum) density (Dmin). The thermal decoloring property was visually determined based on the visible density after development. The actual thermal decoloring property is preferably high in transparency without absorption in the visible part. It is evaluated that decolorization is not good. Since it was impossible to evaluate the attenuation factor at a single wavelength, it was visually evaluated.
The evaluation was performed in a rank system with a decimal point of 1.0 to 5.0 and 5.0.
Is the best thermal decolorability, 1.0 is the worst thermal decolorability,
3.0 represents the middle. Table 1 shows the obtained evaluation results.

[0113]

[Table 1]

From Table 1, it can be seen that the sample of the present invention has excellent thermal decolorability during thermal development, and has excellent sensitivity and fog characteristics both after storage at low humidity and after storage at high humidity. It can be seen that is poor in thermal decolorability during thermal development, and poor in sensitivity and fog characteristics, especially after high-humidity storage, and poor in practicality.

Example 2 The same procedure as in Example 1 was carried out except that the BC layer and its protective layer were coated on the support back of Example 1 and the emulsion layer side was not coated. Twelve types of preliminary samples 2-4 and preliminary samples 2-5 to 2-12 for the present invention were prepared, and the absorption maximum wavelength of the BC dye after coating and drying of each preliminary sample was determined. Next, 12 new samples (comparative samples 2-1 to 2-4 and the present invention) in which the amount of each dye added was changed so that the optical density at the absorption maximum wavelength of each of the preliminary samples was 0.3. Samples 2-5 to 2-12) were prepared. The resulting 12 new samples were heated on a hot drum at 125 ° C. for 15 seconds, and the optical density of the absorption maximum wavelength attenuated by the heating was measured. Samples 1 and 2 using comparative thermal decoloring dyes
The optical density at the maximum absorption wavelength of Sample No. 4 was 0.23, whereas the optical density at the maximum absorption wavelength of Samples 2-5 to 2-12 using the thermo-decolorizable dye of the present invention was 0.18 or less. It can be seen that all of the samples using the thermal decoloring dye of the present invention have excellent thermal decoloring properties.

Example 3 The same procedure as in Example 1 was carried out except that the base-generating precursor compounds of the five types shown in Table 2 were added to the BC layer of the back of the support in an equimolar amount to the thermal decoloring dye, or not added. Samples 3-1 to 3-12 for the present invention were prepared in the same manner as in Example 1. The obtained 12 types of samples were evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[0117]

[Table 2]

From Table 2, all of Samples 3-1 to 3-12 have excellent thermal decolorability during thermal development, and also have excellent sensitivity and fog characteristics after both low-humidity storage and high-humidity storage. Sample 3 to which a base-generating precursor compound was added.
It can be seen that Sample Nos. 2-2 to 3-12 are superior to Sample 3-1 not containing the base-generating precursor compound.

Example 4 In the same manner as in Example 2, a heat-decolorizable dye was added to the BC layer of each sample, and a compound example (2-2) of a base-generating precursor compound in an equimolar amount with each heat-decolorable dye was added. Other than the above, 12 kinds of samples for the present invention (samples 4-1 to 4-1) were prepared in the same manner as in Example 2.
2) was prepared and evaluated. As a result, all of the samples had an optical density of 0.15 or less, which indicates that the use of the base-generating precursor compound of the present invention improves the thermal decoloring property.

Example 5 The procedure of Example 1 was repeated except that the latex shown in Table 3 was used in place of the polyvinyl alcohol in the BC layer containing the thermal decoloring dye in Example 1 at a substitution rate (% by mass) shown in Table 3. Samples 5-1 to 5-12 of the present invention were obtained in the same manner as in Example 1, and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[0121]

[Table 3]

From Table 3, all of Samples 5-1 to 5-12 are excellent in thermal decoloration during thermal development, and excellent in sensitivity and fogging property both after low-humidity storage and after high-humidity storage. Sample 5-2 using the latex of the present invention.
~ 5-12 are the samples 5 to which the latex was not added.
It turns out that it is excellent compared with 1.

Example 6 A sample was prepared in the same manner as in Example 3, except that a polyhalomethane compound in an amount equal to that of the heat-decolorizable dye was added to the layer containing the heat-decolorizable dye as shown in Table 4. -1 to 6-12 were produced.

[0124]

[Table 4]

From Table 4, all of Samples 6-1 to 6-12 were excellent in thermal decoloration during thermal development, and in particular, Sample 6-2 containing the base generating precursor compound and the polyhalomethane compound of the present invention. 6-12 are superior to Sample 6-1 to which the base-generating precursor compound and the polyhalomethane compound were not added.

Example 7 Twelve kinds (comparative sample 7-1 and samples 7-2 to 7-12 for the present invention) were prepared in the same manner as in Example 1 by using nine kinds of thermal decoloring dyes shown in Table 5. ) Was prepared, but here, samples 7-1 to 7-12 were prepared by changing the material of the heat roller of the heat developing machine.
Was developed. Heat developing roller is 123ppm platinum catalyst
A roller obtained by using a heat roller containing 13% by mass of 9 kinds of materials having the following compositions in the used polyorganosiloxane having a degree of polymerization of 7800, and treating the heat developing material (test sample) by 20 times the area of the roller. And the stain of the sample after development were visually evaluated. As for the smoothness, a change in the thickness of the roller (the smoothness of the roller) between a portion where the test piece passed and a portion where the test piece did not pass was visually evaluated. Rank 5.0 represents the best level, rank 1.0 represents the worst level, and rank 3.0 represents an intermediate level. Table 5 shows the evaluation results.

Specific examples of materials mixed in the polyorganosiloxane roller (1) Alumina having an average particle diameter of 0.3 μm (2) Silica having an average particle diameter of 0.3 μm (3) Magnetite particles having an average particle diameter of 0.5 μm (4) ) Hematite particles having an average particle diameter of 0.6 μm (5) Surface treatment of 10% by mass of the particle surface of (4) with alumina (6) Surface treatment of 10% by mass of the particle surface of (4) with silica (7) (4) (5) Surface treatment of 5% by mass of silica and alumina with particles of (8) Particles of (4) doped with 14% by mass of manganese (9) No compounding material

[0128]

[Table 5]

Table 5 shows that the heat-developable materials containing the heat-decolorizable dyes of the present invention and the samples 7-2 to 7-12 of the present invention which were developed using a heat roller made of silicone rubber were used.
Indicates that the heat roller stain, the test sample stain, and the heat roller smoothness are all excellent. Moreover,
Samples 7-3 to 7-12 developed with a heat roller made of silicone rubber containing metal oxides such as alumina and silica, and iron oxides such as magnetite and hematite are excellent. Samples 7-7 to 7-12 developed with a heat roller made of silicone rubber containing iron oxides surface-treated with a material are particularly excellent,
It can be seen that Sample 7-1 using the heat-developable material containing the comparative dye was poor in any of the heat roller stains, the test sample stains, and the heat roller smoothness and poor in practicality.

Example 8 Using the samples 7-1 to 7-12 obtained in Example 7, Table 6
Image formation by changing the angle of the laser light to the film in the image exposure as shown in the above, vertical multi-laser exposure in which the high frequency is superimposed on the laser light or vertical single mode laser exposure in which the high frequency is not superimposed, the obtained Each of the obtained samples is referred to as Samples 8-1 to 8-12, and the presence / absence of occurrence of interference fringe unevenness of the samples is observed. Evaluate,
Table 6 shows the results.

[0131]

[Table 6]

From Table 6, the irradiation laser angle is less than 90 degrees, preferably 55 to 88 degrees. More preferably 60 to 8
It is understood that the interference fringes are improved by setting the angle between 6 degrees, and the generation of the interference fringes is further improved by superimposing a high frequency of the laser beam.

Example 9 Table 7 shows the heat-decolorizable dye, latex and base-generating precursor compound.
Except that the sample was changed as in Example 1 in the same manner as in Example 1.
9-12 were obtained, and the thermal decoloring property and the sensitivity of the 12 kinds of samples were evaluated in the same manner as in Example 1. The results are shown in Table 7. In this example, an AI layer having the following formulation was added between the emulsion layer and the support.

The AI layer, the photosensitive layer and the protective layer of the photosensitive layer
Curtain simultaneous multi-layer coating at a coating speed of 200 m / min 6
It was dried within 2 minutes with a drying air at 0 ° C. BC layer and the BC
The protective layer was similarly coated and dried. The heat decoloring dye of the BC layer was excluded.

In Comparative Sample 9-1, the same mass of photographic inert gelatin was used instead of latex.

Composition of AI layer Polymer latex as binder shown in Table 6 1 g / m ² Thermal decolorable dye shown in Table 6 1.2 × 10 ^-5 mol / m ² Base generating precursor compound shown in Table 6 1. 23 × 1 ^-5 mol / m ² surfactant perfluorooctyl-N-methylsulfonamidoglycine sodium salt 8 mg / m ² dihexyl sulfosuccinate sodium salt 12 mg / m ² thickener ammonium polystyrene sulfonate (molecular weight 500,000) 5 mg / m ² Colloidal silica fine particles 4 mg / m ² Blue tint 1,4-di (2,4,6-triethylphenylamino) anthraquinone 33 mg / m ²

[0137]

[Table 7]

From Table 7, it can be seen that Samples 9-4 to 9-12 of the present invention were obtained.
Is excellent in both thermal decolorability and sensitivity, but Comparative Sample 9
It can be seen that -1 to 9-3 are inferior in either thermal decoloration property or sensitivity and poor in practicality.

[0139]

As demonstrated by the examples, according to the heat-developable material, the method for developing the heat-developable material and the image forming method of the present invention, the sharpness of the image obtained by heat development is high, Excellent thermal decoloring properties of color dyes, less residual color,
The stability of the thermal decoloring dye during storage is high, especially the storage stability of high humidity is excellent, and the occurrence of heat roller stains and deterioration of the roller by the thermal decoloring dye during development is small,
It has excellent effects such as being excellent in stability during long-term running and having a feature that interference fringes are hardly generated on an image when exposed to laser light.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing an example of a heat developing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thermal developing material 2 Conveyance roller 3 Heat source 4 Discharge roller 5 Heat drum 6 Plural heat roller group 7 Developing part 8, 8 'Thermal insulation cover

Claims (8)

[Claims] 1. A heat-developable material having a photosensitive layer containing photosensitive silver halide grains, an organic silver salt and a reducing agent and a non-photosensitive layer on a support, wherein the photosensitive layer or the non-photosensitive layer contains A heat-developable material comprising a dye represented by the formula (1) and decolored by heat at 80 to 200 ° C. Embedded image (Wherein, R ¹ is a hydrogen atom, an aliphatic group which may have a substituent, an aromatic group which may have a substituent, NR ¹¹ R ¹² , OR
¹¹ or SR ¹¹ , wherein R ¹¹ and R ¹² are independently a hydrogen atom,
Represents an aliphatic group or an aromatic group which may have a substituent;
¹¹ and R ¹² may combine to form a heterocycle containing a nitrogen atom. R ² represents a hydrogen atom, an aliphatic group which may have a substituent, or an aromatic group. Z ¹ represents a heterocyclic group containing a nitrogen atom, and Z ² represents an aromatic group having no nitrogen atom. L ¹ represents a divalent linking group having an even number of methine chains, and X represents an anionic group. ) 2. The heat-developable material according to claim 1, wherein the heat-decolorable dye contains a base-generating precursor compound represented by the following general formula (2). Embedded image (In the formula, Z ³ and Z ⁴ each represent an atomic group necessary for forming a 4- to 9-membered ring which may have a substituent, L ² represents a divalent linking group, and Y represents a substituent. n represents a positive number of 0 ≦ n ≦ 4,
When n is 2 or more, adjacent substituents may form a ring. ) 3. The layer containing a dye which is decolorized by heat is coated so that the concentration of the dye with respect to the main wavelength of light is 0.20 or more and 0.18 or less after thermal development. The heat development material according to claim 1, further comprising a layer. 4. The heat according to claim 1, wherein the layer containing a dye which is decolorized by heat contains a latex having a glass transition temperature of -20 to 80 ° C. Development material. 5. The layer according to claim 1, wherein the layer containing a dye which is decolored by heat contains a polyhalomethane compound represented by the following general formula (3). Thermal development material. Embedded image (In the formula, Q represents an aromatic group or a heterocyclic group which may have a substituent, L ³ represents a divalent bonding group, and X represents a halogen atom.) 6. A thermal development, wherein the development of the thermal development material according to any one of claims 1 to 5 is performed using a silicone rubber thermal roller containing a metal oxide. Material development method. 7. The method according to claim 6, wherein at least a part of the metal oxide is a surface-treated iron oxide. 8. An image forming method, wherein the image exposure of the heat-developable material according to claim 1 is performed using a vertical multi-type laser exposure machine.