JPH09329864A - Heat developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive material which has high sensitivity, is low in fogging and has an excellent preservable property before and after processing by incorporating a specific compd. into a heat developable photosensitive material contg. photosensitive silver halide silver particles. SOLUTION: The heat developable photosensitive material contg. the photosensitive silver halide particles in at least either surface of a base contains the compd. expressed by the formula. In the formula, Y denotes a carbamoyl, acylamino, ureido sulfamoyl or sulfonyl amino. L denotes a bivalent hydrocarbon group. M denotes a hydrogen atom or cation. The addition of such compd. may be executed by any method, such as powder, soln., particulate dispersion, etc. The addition in the form of a soln. mixed with other additives, such as sensitizing dyestuff, reducing agent and toning agent, is equally well. While the amt. of the compd. to be added may be any amt., the amt. of >=10μmol to <=100mol per 1mol photosensitive silver halide is preferable and >=1mmol to <=20mol is further preferable.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a photothermographic material (hereinafter sometimes referred to as a photothermographic material).

[0002]

2. Description of the Related Art In recent years, there has been a strong demand in the medical field for reducing the amount of processing waste liquid from the viewpoint of environmental protection and space saving. Thus, a photosensitive heat for medical diagnostics and photographic technology can be efficiently exposed by a laser imagesetter or a laser imager, and can form a sharp black image having high resolution and sharpness. There is a need for technology for developed photographic materials. With these photosensitive photothermographic materials, it is possible to supply a customer with a heat development processing system which eliminates the use of solution processing chemicals and is simpler and does not damage the environment.

On the other hand, semiconductor laser technology, which has made rapid progress in recent years, has enabled downsizing of medical image output devices. Naturally, the technology of infrared-sensitive photothermographic silver halide photographic material that can use a semiconductor laser as a light source was also developed.
No. 387, JP-A-5-341432, JP-A-6-94781, JP-A
No. 6,301,141 is disclosed, and as antihalation techniques, JP-A-7-13295 and US Pat. No. 5,380,635 are disclosed. In the case of a light-sensitive material premised on infrared exposure, the visible absorption of sensitizing dyes and antihalation dyes can be greatly reduced, and a substantially color-free light-sensitive material can be easily produced.

On the other hand, a high-sensitivity photosensitive material can increase the output speed of a laser exposure machine. However, infrared light has a problem that it is difficult to obtain a light-sensitive material having low energy and high sensitivity. Here, it is possible to highly activate and reduce the sensitivity of the reducing agent. Phenols), U.S. Pat. Nos. 4,152,160 and 5,468,
Some reducing agents disclosed in column 603, column 12, line 26 to column 13, line 24 have high activity and high sensitivity, but have the problem of degrading performance stability during storage. Occurs.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photothermographic material having high sensitivity, low fog and excellent preservability before and after processing.

[0006]

This object has been achieved by the following means. (1) A photothermographic material comprising photosensitive silver halide grains on at least one side of a support, which contains a compound represented by formula (I). General formula (I)

[0007]

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(In the formula, Y represents a carbamoyl group, an acylamino group, a ureido group, a sulfamoyl group or a sulfonylamino group. L represents a divalent hydrocarbon group. M represents a hydrogen atom or a cation.) (2 ) A binder, an organic silver salt, on at least one of the supports,
A photothermographic material comprising a reducing agent for silver ions and photosensitive silver halide grains, which contains a compound represented by the general formula (I). General formula (I)

[0009]

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(In the formula, Y represents a carbamoyl group, an acylamino group, a ureido group, a sulfamoyl group or a sulfonylamino group. L represents a divalent hydrocarbon group. M represents a hydrogen atom or a cation.) (3 ) A photothermographic material according to (1) or (2), wherein the compound represented by the general formula (I) is a compound represented by the general formula (IA). General formula (IA)

[0011]

[Chemical 6]

(In the formula, M represents a hydrogen atom or a cation. Ra and Rb are a hydrogen atom, an aliphatic hydrocarbon group, and
It represents an aryl group, a heterocyclic group or a hydroxy group. n represents an integer of 0 to 4. )

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

First, the compound represented by formula (I) will be described in detail. The carbamoyl group, acylamino group and ureido group represented by Y may be unsubstituted or substituted with an aliphatic hydrocarbon group, an aryl group, a heterocyclic group or a hydroxy group, preferably 1 to 40 carbon atoms, more preferably Preferably 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms
belongs to. The sulfamoyl group represented by Y may be unsubstituted or substituted with an aliphatic hydrocarbon group, an aryl group or a heterocyclic group, and preferably has 0 to 40 carbon atoms,
More preferably 0 to 30 carbon atoms, and even more preferably 0 carbon atoms.
~ 20 things. The sulfonylamino group represented by Y is an aliphatic hydrocarbon sulfonylamino group, an arylsulfonylamino group, or a heterocyclic sulfonylamino group,
Preferably 1 to 40 carbon atoms, more preferably 1 to 3 carbon atoms
0, more preferably 1 to 20 carbon atoms.

The above-mentioned aliphatic hydrocarbon group is a linear, branched or cyclic alkyl group (preferably having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, further preferably 1 to 16 carbon atoms, Examples include methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-octyl, 2-ethylhexyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl and the like. ), An alkenyl group (preferably having 2 to 2 carbon atoms).
30, more preferably 2 to 20 carbon atoms, further preferably 2 to 16 carbon atoms, such as vinyl, allyl, 2-butenyl,
3-pentenyl and the like can be mentioned. ), An alkynyl group (preferably having 2 to 30 carbon atoms, more preferably 2 to 20 carbon atoms,
More preferably, it has 2 to 16 carbon atoms, and examples thereof include propargyl and 3-pentynyl. ), And may have a substituent. The aliphatic hydrocarbon group is preferably an alkyl group.

The above aryl group may be monocyclic or condensed, and preferably has 6 to 30 carbon atoms, more preferably has 6 to 20 carbon atoms, and further preferably has 6 to 16 carbon atoms. It is a ring aryl group (eg, phenyl, naphthyl, etc.) and may have a substituent. The aryl group is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

The above heterocyclic group is a 3- to 10-membered saturated or unsaturated heterocycle containing at least one of N, O or S atoms, which may be a monocycle.
Further, a condensed ring may be formed with another ring. The heterocyclic group is preferably a 5- or 6-membered unsaturated heterocyclic group, and more preferably a 5- or 6-membered aromatic heterocyclic group. More preferably, it is a 5- to 6-membered aromatic heterocyclic group containing a nitrogen atom, particularly preferably a 5- to 6-membered aromatic heterocyclic group containing a 1 to 4 nitrogen atom, and having a substituent. Good.

Specific examples of the heterocycle include pyrrolidine, piperidine, piperazine, morpholine, imidazoline, thiazoline, oxazoline, indoline, pyrazoline, thiophene, furan, pyrrole, imidazole, pyrazole, pyridine, pyrimidine, pyrazine, pyridazine, triazole. , Triazine, indole, indazole, purine, thiazole, thiadiazole, oxazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzthiazole, Examples include benzselenazole, indolenine, tetraazaindene, perimidine and the like. The heterocycle is preferably imidazole, pyrazole, pyridine, pyrimidine, pyrazine,
Pyridazine, triazole, triazine, indole,
Indazole, purine, thiazole, thiadiazole,
Oxazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzthiazole, indolenine, tetraazaindene, perimidine.

The substituents on the above-mentioned aliphatic hydrocarbon group, aryl group and heterocyclic group are, for example, alkyl groups (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 carbon atoms). To 8 and examples thereof include methyl, ethyl, iso-propyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.), alkenyl group (preferably having carbon atoms). 2-20, more preferably 2 carbon atoms
To 12, particularly preferably 2 to 8 carbon atoms, and examples thereof include vinyl, allyl, 2-butenyl, 3-pentenyl and the like. ), An alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms).
And examples thereof include 1-propynyl and 3-pentynyl. ), An aryl group (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 30 carbon atoms).
12 and examples thereof include phenyl, p-methylphenyl, naphthyl and the like. ), An amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms, and examples thereof include amino, methylamino, dimethylamino, diethylamino and dibenzylamino. , An alkoxy group (preferably having 1 carbon atom)
To 20, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms, and examples thereof include methoxy, ethoxy, butoxy and the like. ), An aryloxy group (preferably having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as phenyloxy,
2-naphthyloxy and the like can be mentioned. ), An acyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms,
Particularly preferably, it has 1 to 12 carbon atoms, such as acetyl,
Examples thereof include benzoyl, formyl and pivaloyl. ), An alkoxycarbonyl group (preferably having 2 carbon atoms)
To 20, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 12 carbon atoms, and examples thereof include methoxycarbonyl and ethoxycarbonyl. ), An aryloxycarbonyl group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, and particularly preferably 7 to 10 carbon atoms, such as phenyloxycarbonyl).
Acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include acetoxy and benzoyloxy). Acylamino group (preferably having carbon number) 2-20,
More preferably 2 to 16 carbon atoms, and particularly preferably 2 carbon atoms.
To 10 and examples thereof include acetylamino and benzoylamino. ), An alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 2 carbon atoms).
16, particularly preferably having 2 to 12 carbon atoms, such as methoxycarbonylamino. ), An aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 20 carbon atoms).
12 and examples thereof include phenyloxycarbonylamino. ), A sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include methanesulfonylamino and benzenesulfonylamino).
Sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, and examples thereof include sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, phenylsulfamoyl and the like. ), A carbamoyl group (preferably having 1 carbon atom).
To 20, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include carbamoyl, methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl and the like. ), An alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include methylthio and ethylthio), an arylthio group (preferably carbon). C 6-20, more preferably C 6-16, particularly preferably C 6-12, such as phenylthio, etc.), sulfonyl group (preferably C 1).
20, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include mesyl and tosyl. ), A sulfinyl group (preferably having a carbon number of 1 to 20, more preferably a carbon number of 1 to 16, and particularly preferably a carbon number of 1 to 1).
12, for example, methanesulfinyl, benzenesulfinyl and the like. ), An ureido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include ureido, methylureido, phenylureido, etc.) and phosphoric acid. Amido group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include diethylphosphoric acid amide and phenylphosphoric acid amide). , A mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a cyano group, a sulfo group, a carboxyl group, a nitro group, a hydroxamic acid group, a sulfino group, a hydrazino group, a heterocyclic group (for example, imidazolyl, Pyridyl, furyl, piperidyl, morpholino, etc.) and the like. These substituents may be further substituted. When there are two or more substituents, they may be the same or different.

The substituent is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group. ,
Aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, ureido group,
A hydroxy group, a halogen atom, a cyano group, and a heterocyclic group.

Y is preferably a carbamoyl group, an acylamino group or a ureido group, more preferably a carbamoyl group, still more preferably an aliphatic hydrocarbon-substituted carbamoyl group, and particularly preferably an alkyl group. Carbamoyl group.

As the divalent hydrocarbon group represented by L,
For example, a linear, branched or cyclic alkylene group (preferably having 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, further preferably 1 to 4 carbon atoms, for example, methylene, ethylene, trimethylene, propylene, ethylethylene). , Hexamethylene, 1,2-cyclohexylene and the like), alkenylene group (preferably having 2 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, and further preferably 2 to 4 carbon atoms).
And examples thereof include vinylene and propenylene. ), An alkynylene group (preferably having 2 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, and still more preferably 2 to 8 carbon atoms).
4 and examples thereof include ethynylene, 3-pentynyl and the like. ), An aryl group (preferably having 6 to 20 carbon atoms,
More preferably 6 to 16 carbon atoms, and even more preferably 6 carbon atoms.
-12, and examples thereof include phenylene and naphthylene. ), An aralkylene group (preferably having 7 to 20 carbon atoms,
More preferably, it has 7 to 16 carbon atoms, and even more preferably 7 carbon atoms.
-12, and examples thereof include xylylene. ).

The divalent hydrocarbon group represented by L is preferably an alkylene group or an arylene group, more preferably methylene, ethylene, propylene, phenylene,
It is a naphthylene group, more preferably phenylene, and most preferably ortho-phenylene.

The divalent hydrocarbon group represented by L may have a substituent, and examples of the substituent include the substituents of the aliphatic hydrocarbon group, the aryl group and the heterocyclic group in the description of Y. Anything can be applied. The substituent of L is preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, Aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, ureido group, hydroxy group, halogen atom, cyano group, heterocyclic group, more preferably alkyl group and halogen atom, particularly preferably alkyl group Is. In addition, Y and L may be linked to form a ring.

The cation represented by M represents an organic or inorganic cation, such as an alkali metal ion (Li ⁺ , Na).
⁺ , K ⁺ , Cs ^+, etc.), alkaline earth metal ions (Mg
²⁺ , Ca ^2+, etc.), ammonium (ammonium, trimethylammonium, triethylammonium, tetramethylammonium, tetraethylammonium, tetrabutylammonium, 1,2-ethanediammonium, etc.), pyridinium, imidazolium, phosphonium (tetrabutylphosphonium, etc.) ) And the like.
M is preferably a hydrogen atom or an alkali metal ion, and more preferably a hydrogen atom. Among the compounds represented by formula (I), preferably, Y is a carbamoyl group and L is an arylene group.

Among the compounds represented by the general formula (I), the compounds represented by the following general formula (IA) are more preferred. General formula (IA)

[0027]

[Chemical 7]

In the formula, M has the same meaning as in formula (I) and the preferred range is also the same. Ra and Rb are
Each represents a hydrogen atom, an aliphatic hydrocarbon group, an aryl group, a heterocyclic group or a hydroxy group. The aliphatic hydrocarbon group, aryl group and heterocyclic group represented by Ra and Rb have the same meanings as those described in the description of Y in formula (I), and the preferred ranges are also the same. At least one of Ra and Rb is preferably an aliphatic hydrocarbon group, more preferably both are aliphatic hydrocarbon groups, particularly preferably both are alkyl groups, and most preferably both have 3 to 10 carbon atoms. Is an alkyl group. R represents a substituent, has the same meaning as the substituent of the aryl group described in the description of Y in formula (I), and the preferred range is also the same. n represents an integer of 0 to 4, preferably 0, 1 or 2, more preferably 0 or 1, and particularly preferably 0. )

Specific examples of the compound represented by formula (I) are shown below, but the invention is not limited thereto.

[0030]

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[0031]

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[0032]

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[0033]

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[0034]

[Chemical 12]

[0035]

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The compound represented by the general formula (I) of the present invention is commercially available and can be easily obtained and synthesized. The above compounds may be used in the form of salts.

The compound represented by formula (I) in the present invention may be added to any part of the light-sensitive material.
The addition layer is preferably added to the layer having the photosensitive layer, and more preferably to the organic silver salt-containing layer. The compound represented by the general formula (I) of the present invention may be added at any step during the preparation of the coating solution. Although any steps may be used, it is preferable to perform after the preparation of the organic silver salt and immediately before coating. The method of adding the compound represented by the general formula (I) of the present invention may be any method such as powder, solution and fine particle dispersion. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent and a color tone agent. The compound represented by the general formula (I) of the present invention may be added in any amount, but is preferably 10 μmol or more and 100 mol or less, more preferably 1 mmol or more and 20 mol or less, per mol of the photosensitive silver halide.

The photothermographic material of the present invention comprises one or more layers on a support. At least one layer must contain light-sensitive silver halide grains and include organic silver salts, reducing agents and binders for silver ions, and optional additional materials such as toning agents, coating aids and other auxiliaries. It is preferable to include. For a two-layer configuration,
It contains the organic silver salt and silver halide in the first emulsion layer (usually the layer adjacent to the substrate) and some other ingredients in the second layer or both layers. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. The construction of a multicolor photothermographic material may include a combination of these two layers for each color, or may include all components in a single layer as described in U.S. Pat.No. 4,708,928. Is also good. In the case of multi-dye multi-color light-sensitive photothermographic materials, each light-sensitive layer is generally described in U.S. Pat.
As described in US Pat. No. 4,460,681, a functional or non-functional barrier layer is used between each photosensitive layer to keep them separate from each other.

The sensitizing dye in the present invention may be any one as long as it can spectrally sensitize the silver halide grains in a desired wavelength region when adsorbed on the photosensitive silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holoholer cyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye and the like can be used. Useful sensitizing dyes used in the present invention are, for example, RESEARCH DISCLOSURE
Item17643IV-A (December 1978, p.23), Item1831X Item (August, 1979, p.437), or the references cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers, scanners, imagesetters and plate making cameras can be advantageously selected.

As an example of spectral sensitization to red light, He-Ne
For the laser light source, the I-beam described in JP-A-54-18726 is used.
-1 to I-38, I-1 described in JP-A-6-75322
To I-35 and the compounds described in JP-A-7-287338.
Compounds of -1 to I-34, for LED light source
Dyes 1 to 20 described in JP-A-9818, compounds of I-1 to I-37 described in JP-A-62-284343, compounds of I-1 to I-34 described in JP-A-7-287338, and the like. Advantageously selected.

For spectrally sensitizing silver halide grains in any wavelength range from 750 to 1400 nm, specifically, a photosensitive silver halide is prepared by adding cyanine, merocyanine, styryl, hemicyanine, oxonol, hemioxonol and Various known dyes, including xanthene dyes, can be spectrally favored for sensitization. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nuclei, oxazoline nuclei, pyrroline nuclei, pyridine nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei and imidazole nuclei. Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus. Including. Among the above cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Pat.
No. 3,719,495; No. 3,877,943; British Patent No.
Nos. 1,466,201, 1,469,117, 1,422,057,
Japanese Patent Publication No. 3-10391, Japanese Patent Publication No. 6-52387, Japanese Patent Laid-Open No. 5-341432
Nos. 6,194,781 and 6,301,141 may be appropriately selected from known dyes. A particularly preferred structure of the dye is a cyanine dye having a thioether bond, and examples thereof include JP-A-62-58239 and 3-1386.
38,3-138642,4-255840,5-72659,5-72661,6-2224
91, 2-230506, 6-258757, 6-317868, 6-324425, Tokiohei
7-500926.

These sensitizing dyes may be used alone,
Two or more kinds may be used in combination. Combinations of sensitizing dyes are often used, especially for supersensitization. Along with the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are Re.
search Disclosure Volume 176 Volume 17643 (Issued December 1978) No. 23
It is described in item J on page IV, Japanese Patent Publication Nos. 49-25500 and 43-4933, and JP-A-59-19032 and 59-192242.

The sensitizing dyes used in the present invention may be used in combination of two or more kinds. The sensitizing dyes can be added to the silver halide emulsion by dispersing them directly in the emulsion or by using water, methanol, ethanol, propanol, acetone, methylcellosolve, 2,2,3,3 -Tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-
A solvent such as methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, N-dimethylformamide or the like may be dissolved in a single or mixed solvent and added to the emulsion. Further, as disclosed in US Pat. No. 3,469,987, a method of dissolving a dye in a volatile organic solvent, dispersing the solution in water or a hydrophilic colloid, and adding the dispersion to an emulsion. , JP-B-44-23389,
As disclosed in 44-27555, 57-22091, etc.,
As disclosed in U.S. Pat.Nos. 3,822,135, 4,006,025, etc., a method in which a dye is dissolved in an acid and the solution is added to the emulsion, or an acid or a base is coexistent to be added to the emulsion as an aqueous solution. A method of adding an aqueous solution or colloidal dispersion in which a surfactant coexists to the emulsion, as disclosed in JP-A-53-102733 and JP-A-58-105141, a dye is incorporated into a hydrophilic colloid. Is directly dispersed, and the dispersion is added to the emulsion, as described in JP-A-51-74624, the dye is dissolved using a compound that shifts red, and the solution is added to the emulsion. The method of doing can also be used. Also, ultrasonic waves can be used for the solution. The sensitizing dye used in the present invention may be added to the silver halide emulsion of the present invention at any step in the preparation of an emulsion which has heretofore been found to be useful. For example, U.S. Patent Nos. 2,735,766 and 3,628,960
No. 4,183,756, No. 4,225,666, JP-A-58-1
As disclosed in the specification of No. 84142, No. 60-196749, etc., chemical ripening can be carried out during the grain formation step of silver halide or / and before desalting, during the desilvering step and / or after desalting. Before the start of the emulsion, as disclosed in the specification of JP-A-58-113920, immediately before chemical ripening or during the process, after chemical ripening, before the emulsion is coated. If so, it may be added at any stage in the process. Also, U.S. Pat. No. 4,225,666 and JP-A-58-762.
As disclosed in the specification of No. 9, etc., the same compound may be used alone or in combination with a compound having a different structure, for example, during the particle formation step and during the chemical ripening step or after the completion of the chemical ripening, The compound may be added in portions such as before aging or during the process and after completion, or may be added by changing the kind of compound to be added and the combination of compounds.

The photothermographic material of the present invention has a so-called single-sided photosensitive material having a photosensitive layer containing at least one photosensitive silver halide grain on one side of a support and a backing layer on the other side. It is preferably a material.

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

The shape of the silver halide grains is cubic,
Octahedral, tabular particles, spherical particles, rod-like particles, potato-like particles and the like can be mentioned. In the present invention, cubic particles and tabular particles are particularly preferable. When tabular silver halide grains are used, the average aspect ratio is preferably from 100: 1 to 2: 1, more preferably from 50: 1 to 3: 1. Further, grains having rounded corners of silver halide grains can also be preferably used. The surface index (mirror index) of the outer surface of the photosensitive silver halide grains is not particularly limited, but the ratio of the [100] plane, which has high spectral sensitization efficiency when the spectral sensitizing dye is adsorbed, is high. preferable. The ratio is preferably at least 50%, more preferably at least 65%, even more preferably at least 80%. The ratio of Miller index [100] planes is T. Tani; J. Imaging Sci., 29, which utilizes the adsorption dependence of the [111] and [100] planes in the adsorption of sensitizing dyes.
165 (1985).
The halogen composition of the photosensitive silver halide is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, and silver iodide. In the present invention, silver bromide or silver iodobromide can be preferably used. Silver iodobromide is particularly preferred, and the silver iodide content is preferably 0.1 mol% or more and 40 mol% or less,
It is more preferably 0.1 mol% or more and 20 mol% or less. The distribution of the halogen composition in the grains may be uniform, the halogen composition may be changed stepwise, or may be changed continuously, but as a preferable example, the silver iodide content inside the grains is High silver iodobromide grains can be used. Preferably, silver halide grains having a core / shell structure can be used. The structure is preferably a two- to five-fold structure, more preferably a two to four-fold structure.
Heavy core / shell particles can be used.

The photosensitive silver halide grain of the present invention preferably contains at least one metal complex selected from rhodium, rhenium, ruthenium, osmium, iridium, cobalt or iron. These metal complexes are 1
One kind may be used, or two or more kinds of same metal and different metal complexes may be used in combination. The preferred content is 1n per mol of silver
A range of 10 to 10 mmol is preferable, and 10 to 100 mmol is preferable.
A μmol range is more preferred. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used. As the compound of cobalt and iron, a hexacyano metal complex can be preferably used.
Specific examples include ferricyanate ion, ferrocyanate ion, hexacyanocobaltate ion, and the like, but are not limited thereto. The phase containing the metal complex in the silver halide may be uniform, may be contained in the core at a high concentration, or may be contained in the shell at a high concentration, and there is no particular limitation.

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

The photosensitive silver halide grains in the present invention are preferably chemically sensitized. As a preferred chemical sensitization method, a sulfur sensitization method, a selenium sensitization method, and a tellurium sensitization method are well known in the art. Further, a noble metal sensitization method or a reduction sensitization method of a gold compound, platinum, palladium, an iridium compound or the like can be used. As the compound preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds can be used, and the compounds described in JP-A-7-128768 can be used. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides,
Bis (carbamoyl) tellurides, diacyltellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, compounds having a P = Te bond,
Tellurocarboxylates, Te-organyltellurocarboxylates, di (poly) tellurides, tellurides,
Tellurols, telluroacetals, tellursulfonates, compounds having a P-Te bond, Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, and the like can be used. Compounds preferably used in the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate,
Gold sulfide, gold selenide, or US Patent 2,448,060
Compounds described in Japanese Patent No. 618,061 and the like can be preferably used. Specific compounds of the reduction sensitization method include, as well as ascorbic acid, thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds,
A polyamine compound or the like can be used. Further, reduction sensitization can be carried out by ripening while maintaining the pH of the emulsion at 7 or more or pAg at 8.3 or less. Further, reduction sensitization can be performed by introducing a single addition portion of silver ions during grain formation.

The amount of the photosensitive silver halide used in the present invention is preferably 1 mg or more and 5 g or less and more preferably 10 mg or more and 1 g or less per 1 m ² of the light-sensitive material. Regarding the mixing method and the mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide particles and the organic silver salt are respectively mixed with a high-speed stirrer, a ball mill, a sand mill,
There are a method of mixing with a colloid mill, a vibration mill, a homogenizer, etc., and a method of preparing an organic silver salt by mixing photosensitive silver halide prepared at any timing during the preparation of the organic silver salt. There is no particular limitation as long as the effects of the present invention are sufficiently exhibited.

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

It is also possible to use silver salts of compounds containing a mercapto group or a thione group and derivatives thereof. Preferred examples of these compounds include 3-mercapto-4-
Phenyl-1,2,4-triazole silver salt, 2-mercaptobenzimidazole silver salt, 2-mercapto-5-aminothiadiazole silver salt, 2- (ethylglycolamido) benzothiazole silver salt, S-alkylthio Silver salt of thioglycolic acid such as silver salt of glycolic acid (wherein the alkyl group has 12 to 22 carbon atoms), silver salt of dithiocarboxylic acid such as silver salt of dithioacetic acid, silver salt of thioamide, 5- Carboxyl-1-methyl-2-phenyl-4-thiopyridine silver salt, mercaptotriazine silver salt, 2-mercaptobenzoxazole silver salt, the silver salt described in U.S. Pat.
For example, a silver salt of a 1,2,4-mercaptothiazole derivative such as a silver salt of 3-amino-5-benzylthio-1,2,4-thiazole,
Includes silver salts of thione compounds such as the silver salt of 3- (3-carboxyethyl) -4-methyl-4-thiazoline-2-thione described in US Pat. No. 3,301,678. Furthermore, compounds containing an imino group can be used. Preferred examples of these compounds include silver salts of benzotriazole and derivatives thereof, for example, silver salts of benzotriazole such as silver methylbenzotriazole, silver salts of halogen-substituted benzotriazoles such as silver 5-chlorobenzotriazole, U.S. Pat. Nos. 4,220,709, including silver salts of 1,2,4-triazole or 1-H-tetrazole, silver salts of imidazole and imidazole derivatives, and the like. For example, U.S. Pat.
Various silver acetylide compounds as described in 1,361 and 4,775,613 can also be used.

The shape of the organic silver salt that can be used in the present invention is not particularly limited, but a needle crystal having a short axis and a long axis is preferable. Since the inversely proportional relationship between the size of silver salt crystal grains and the covering power is well established in the photothermographic material of the present invention as well known in the light-sensitive silver halide photographic material, that is, the photothermographic material It is necessary to reduce the size of the organic silver salt, because if the organic silver salt particles that are the image forming part of the material are large, it means that the covering power is low and the image density is low. In the present invention, the minor axis 0.01
μm or more and 0.20 μm or less, long axis 0.10 μm or more and 5.0 μm or less, short axis 0.01 μm or more and 0.15 μm or less, long axis 0.10
It is more preferably at least μm and at most 4.0 μm. The particle size distribution of the organic silver salt is preferably monodispersed. Monodisperse is the 100% of the value obtained by dividing the standard deviation of the lengths of the short axis and the long axis by the short axis and the long axis, respectively, preferably 100% or less, more preferably 80% or less, and further preferably 50%. It is the following.
The shape of the organic silver salt can be measured from a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring monodispersity, there is a method of obtaining the standard deviation of the volume-weighted average diameter of the organic silver salt, and the 100-percentage (variation coefficient) of the value divided by the volume-loaded average diameter is preferably 100% or less. ,
It is more preferably at most 80%, further preferably at most 50%. As a measuring method, for example, the particle size (volume-weighted average diameter) obtained by irradiating an organic silver salt dispersed in a liquid with a laser beam and obtaining an autocorrelation function for the time change of the scattered light fluctuation You can

The organic silver salt of the present invention can be used in a desired amount, but it is preferably 0.1 to 5 g / m ² , and more preferably 1 to 3 g.
/ m ² .

The reducing agent for the organic silver salt may be any substance that reduces silver ions to metallic silver, preferably an organic substance. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred. The reducing agent is used in one of the image forming layers.
Should be present as ~ 10% by weight. When a reducing agent is added to a layer other than the emulsion layer in a multilayer structure,
A slightly higher percentage, about 2-15%, tends to be more desirable.

A wide range of reducing agents have been disclosed in the photothermographic materials utilizing organic silver salts. For example, phenylamide oxime, 2-thienylamide oxime and p-
Amide oximes such as phenoxyphenylamidoxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; fats such as a combination of 2,2-bis (hydroxymethyl) propionyl-β-phenylhydrazine and ascorbic acid Combinations of aromatic carboxylic acid aryl hydrazides with ascorbic acid; polyhydroxybenzene and hydroxylamine, reductone and / or
Or a combination of hydrazines (eg, hydroquinone and
Bis (ethoxyethyl) hydroxylamine, a combination of piperidinohexose reductone or formyl-4-methylphenylhydrazine); hydroxamic acids such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-alinine hydroxamic acid; A combination of azine and sulfonamidophenol (for example, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol); α such as ethyl-α-cyano-2-methylphenylacetate, ethyl-α-cyanophenylacetate -Cyanophenylacetic acid derivatives; 2,2-dihydroxy-1,1-binaphthyl, 6,6-dibromo-2,2-dihydroxy
Bis-β-naphthol as exemplified by -1,1-binaphthyl and bis (2-hydroxy-1-naphthyl) methane;
Bis-β-naphthol and a 1,3-dihydroxybenzene derivative (eg, 2,4-dihydroxybenzophenone or 2,
5-pyrazolone, such as 3-methyl-1-phenyl-5-pyrazolone;
Diducts such as dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone; 2,6-dichloro-4-benzenesulfonamidephenol and p-benzenesulfone Sulfonamide phenol reducing agents such as amidophenol; 2-phenylindane-1,3-dione etc .; Chroman such as 2,2-dimethyl-7-t-butyl-6-hydroxychroman; 2,6-dimethoxy-3, 1,4-dihydropyridines such as 5-dicarboethoxy-1,4-dihydropyridine; bisphenols (eg,
Bis (2-hydroxy-3-t-butyl-5-methylphenyl)
Methane, 2,2-bis (4-hydroxy-3-methylphenyl)
Propane, 4,4-ethylidene-bis (2-t-butyl-6-methylphenol), 1,1, -bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane and the like); ascorbic acid derivatives (for example, palmitic acid 1-
Ascorbyl, ascorbyl stearate, etc.); and aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indane-1,3-
Dione; chromanol (tocopherol and the like); Particularly preferred reducing agents are bisphenol and chromanol.

In addition to the components described above, it may be advantageous to include additives known as "toning agents" to improve the image. For example, the toning agent material has a total silver holding component of 0.1 to
It may be present in an amount of 10% by weight. Toning agents are disclosed in U.S. Pat.
It is a material well known in the photographic art as shown in 080,254, 3,847,612 and 4,123,282.

Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazoline-5-
Quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and
Cyclic imides such as 2,4-thiazolidinedione; naphthalimides (eg, N-hydroxy-1,8-naphthalimide); cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4 -Triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5
-Mercaptans exemplified by diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole; N- (aminomethyl) aryldicarboximides;
(For example, (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-
Dicarboxyimide); and blocked pyrazoles, isothiuronium derivatives, and certain photobleaching agents (eg, N, N-hexamethylenebis (1-carbamoyl-
3,5-dimethylpyrazole), 1,8- (3,6-diazaoctane) bis (isothiuronium trifluoroacetate)
And 2-tribromomethylsulfonyl)-(benzothiazole)); and 3-ethyl-5 (3-ethyl-2-benzothiazolinylidene) -1-methylethylidene-2-thio-2,4-oxazolidinedione Phthalazinone, phthalazinone derivatives or metal salts, or derivatives such as 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione A combination of phthalazinone and a phthalic acid derivative (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); phthalazine, a phthalazine derivative or a metal salt, or 4- (1-naphthyl) phthalazine , Derivatives such as 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (eg phthalates) ,
Quinazolinedione, such as 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride;
Benzoxazine or naphthoxazine derivatives; rhodium complexes that function not only as toning agents but also as a source of halide ions for silver halide formation in situ, eg ammonium hexachlororhodium (III), rhodium bromide, rhodium nitrate And potassium hexachlororhodium (III) ate; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide; 1,3-benzoxazine-2,4-dione, 8-methyl
-1,3-benzoxazine-2,4-dione and 6-nitro-
Benzoxazine-2,4-diones such as 1,3-benzoxazine-2,4-dione; pyrimidines and asymmetric-triazines (eg 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), Azauracil and tetraazapentalene derivatives (eg 3,6-dimercapto-1,4-diphenyl-1H, 4H-2,3a, 5,6a-tetraazapentalene, and 1,4-di (o-chlorophenyl ) -3,6-dimercapto-1H, 4H-2,3a, 5,6a-tetraazapentalene).

In the present invention, the compound represented by the general formula (I) of the present invention is used for controlling the increase in fog due to development, improving the spectral sensitization efficiency, and improving the preservability before and after development. It is preferable to use a mercapto compound, a disulfide compound, and a thione compound together. When the mercapto compound is used in the present invention, it may have any structure, but those represented by Ar-SM ₁ and Ar-SS-Ar are preferable. In the formula, M ₁ is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or a condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole,
Benzoselenazole, benzoterrazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring may be, for example, halogen (eg Br and Cl), hydroxy, amino,
Carboxy, alkyl (eg, one or more carbon atoms,
Preferably those having 1 to 4 carbon atoms) and alkoxy (eg one or more carbon atoms, preferably 1
To those having from 4 carbon atoms). As the mercapto-substituted heteroaromatic compound, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole,
2,2'-dithiobis- (benzothiazole, 3-mercapto-
1,2,4-triazole, 4,5-diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-
Mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol,
2,3,5,6-Tetrachloro-4-pyridinethiol, 4-amino
-6-hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4-thiadiazole,
3-Amino-5-mercapto-1,2,4-triazole, 4-hydroxy-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2-mercapto-4-methylpyrimidinehydro Chloride, 3-mercapto-5-phenyl-1,2,4-triazole, 2-mercapto
-4-Phenyloxazole and the like are included, but the present invention is not limited thereto.

The addition amount of these mercapto compounds is preferably in the range of 0.001 to 1.0 mol per mol of silver in the photosensitive layer, more preferably 0.01 to 1.0 mol per mol of silver.
The amount is 0.3 mol.

The light-sensitive material of the present invention may be provided with a surface protective layer for the purpose of preventing adhesion of the image forming layer.
Any anti-adhesion material may be used as the surface protective layer. Examples of anti-adhesion materials include waxes, silica particles, styrene-containing elastomeric block copolymers (eg, styrene-butadiene-styrene, styrene-isoprene-styrene), cellulose acetate, cellulose acetate butyrate, cellulose propionate, and the like. And mixtures.

In the present invention, the layer containing the photosensitive silver halide grains or the protective layer for the layer is described in US Pat.
It can be used in photographic elements containing light absorbing materials and filter dyes such as those described in 3,921, 2,274,782, 2,527,583 and 2,956,879. Alternatively, dyes can be mordant as described in, for example, US Pat. No. 3,282,699. The amount of the filter dye used is preferably such that the absorbance at the exposure wavelength is 0.1 to 3, particularly 0.2 to 1.5. For the layer containing the photosensitive silver halide grains or the protective layer of the layer in the present invention, a matting agent such as starch, titanium dioxide, zinc oxide, silica, U.S. Pat. Nos. 2,992,101 and 2,70
Polymer beads including beads of the type described in 1,245 can be included. The matteness of the emulsion surface may be anything as long as stardust failure does not occur, but it is preferable that the Beck's smoothness is 300 seconds or more and 10,000 seconds or less.
It is preferably 500 seconds or more and 8000 seconds or less.

The binder for the layer containing the photosensitive silver halide grains in the invention is a well-known natural or synthetic resin such as gelatin, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate,
Any one can be selected from cellulose acetate, polyolefin, polyester, polystyrene, polyacrylonitrile, polycarbonate and the like. Of course, copolymers and terpolymers are also included.
Preferred polymers are polyvinyl butyral, butylethyl cellulose, methacrylate copolymers, maleic anhydride copolymers, polystyrene and butadiene-styrene copolymers. If necessary, two or more of these polymers can be used in combination. Such a polymer is used in an amount sufficient to hold the components therein. That is, it is used in a range effective to function as a binder. The effective range can be appropriately determined by those skilled in the art. As a guide for holding at least the organic silver salt, the ratio of the binder to the organic silver salt is 15: 1 to 1: 2, especially 8: 1.
A range of １1: 1 is preferred.

In the present invention, a matte agent may be added to the one-sided photosensitive material in order to improve transportability. The matting agent is generally fine particles of an organic or inorganic compound insoluble in water. Any matting agent can be used, for example, U.S. Pat.Nos. 1,939,213, 2,701,245 and 2,322,037.
No. 3,262,782, No. 3,539,344, No. 3,767,448, etc., the organic matting agent described in each specification, No. 1,260,772,
2,192,241, 3,257,206, 3,370,951,
Inorganic matting agents described in the respective specifications such as 3,523,022 and 3,769,020 and the like well known in the art can be used. For example, specifically as an example of an organic compound that can be used as a matting agent, as an example of a water-dispersible vinyl polymer, polymethyl acrylate, polymethyl methacrylate, polyacrylonitrile, acrylonitrile-α-methylstyrene copolymer, polystyrene , Styrene-divinylbenzene copolymer, polyvinyl acetate, polyethylene carbonate, polytetrafluoroethylene, etc. Examples of cellulose derivatives are methyl cellulose, cellulose acetate, cellulose acetate propionate, etc. Examples of starch derivatives are carboxy starch, carboxynitrophenyl Gelatin which has been hardened with a known hardening agent such as starch, urea-formaldehyde-starch reaction product, etc. and hard gelatin such as coacervate hardened into fine capsule hollow particles are preferable. It can be used properly. As examples of the inorganic compound, silicon dioxide, titanium dioxide, magnesium dioxide, aluminum oxide, barium sulfate, calcium carbonate, silver chloride desensitized by a known method, silver bromide, glass, diatomaceous earth and the like can be preferably used. . The above matting agents can be used by mixing different types of substances as necessary. The size and shape of the matting agent are not particularly limited, and those having an arbitrary particle size can be used. In the practice of the present invention, 0.1 μm
It is preferable to use particles having a particle size of 30 μm. Further, the particle size distribution of the matting agent may be narrow or wide. On the other hand, since the matting agent has a great influence on the haze and surface gloss of the light-sensitive material, the particle size, shape, and particle size distribution can be adjusted to the required state during the preparation of the matting agent or by mixing a plurality of matting agents. preferable.

In the present invention, as the matteness of the backing layer, Beck's smoothness is preferably 250 seconds or less and 10 seconds or more,
More preferably, it is 180 seconds or less and 50 seconds or more. In the present invention, the matting agent is preferably contained in the outermost surface layer of the light-sensitive material, a layer functioning as the outermost surface layer, or a layer close to the outer surface, and also contained in a layer acting as a so-called protective layer. It is preferable.

Suitable binders for the backing layer in the present invention are transparent or translucent, generally colorless, and include natural polymers such as synthetic resins, polymers and copolymers, and other film forming media such as: gelatin, gum arabic, poly (vinyl). Alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinylpyrrolidone), casein, starch, poly (acrylic acid), poly (methylmethacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (Styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (for example, poly (vinyl formal) and poly (vinyl butyral)), poly (ester) s, Poly Urethanes), phenoxy resins, poly (vinylidene chloride), poly (epoxides),
Poly (carbonate) s, poly (vinyl acetate),
There are cellulose esters and poly (amides). The binder may be coated from water or an organic solvent or an emulsion.

In the present invention, the backing layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less, more preferably 0.5 or more and 2 or less, and an absorption in the visible region of 0.001 or less. It is preferably not less than 0.5 and more preferably not less than 0.001 and not more than 0.00.
Preferably, the antihalation layer has an optical density of less than 3.

When the antihalation dye is used in the present invention, the dye has a desired absorption in a desired wavelength range, has a sufficiently small absorption in the visible region, and has a preferable absorbance spectrum shape of the backing layer. Any compound can be used. For example, JP-A-7-13295, U.S. Pat.
No. 0,635, JP-A-2-68539, page 13, lower left column, line 1 to page 14, lower left column, line 9; JP-A-3-24539, page 14, lower left column to page 16, lower right Although the compounds described in the column are mentioned, the present invention is not limited thereto.

US Pat. Nos. 4,460,681 and 4,374,
The backside resistive heating layer (backside re
A sistive heating layer) can also be used in a photothermographic image system.

Silver halide grains in the invention or /
And the organic silver salts can be further protected against the formation of additional fog and stabilized against loss of sensitivity during storage by antifoggants, stabilizers and stabilizer precursors. Suitable antifoggants, stabilizers and stabilizer precursors that can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716, U.S. Pat.Nos. 2,886,437 and 2,444,605. Azaindene, U.S. Pat.
No. 728,663, mercury salts described in U.S. Pat.No. 3,287,135, sulphocatechol described in U.S. Pat.No. 3,235,652, oximes described in British Patent No.
No. 405, polyvalent metal salts, U.S. Pat.No. 3,220,839, thyuronium salts, and U.S. Pat.
, Platinum and gold salts described in U.S. Pat. No. 4,597,915 and U.S. Pat. Nos. 4,108,665 and 4,442,20.
Halogen-substituted organic compounds described in US Pat. No. 4,12
Nos. 8,557 and 4,137,079, 4,138,365 and 4,459,350, and the phosphorus compounds described in U.S. Pat. No. 4,411,985.

The antifoggants preferably used in the present invention are organic halides, for example, JP-A-50-119624.
No. 50, No. 50-120328, No. 51-121332, No. 54-58022,
56-70543, 56-99335, 59-90842, 61-129
No. 642, No. 62-129845, JP-A-6-208191, No. 7-5621
Nos. 7-2781, 8-15809, U.S. Pat.No. 5,340,712
Nos. 5,369,000 and 5,464,737.

The photosensitive layer in the present invention contains a polyhydric alcohol as a plasticizer and a lubricant (see, for example, US Pat.
Glycerin and diols of the type described in U.S. Pat. No. 960,404), fatty acids or esters described in U.S. Pat. Nos. 2,588,765 and 3,121,060, and silicone resins described in British Patent No. 955,061.

A hardener may be used in each layer such as the photosensitive layer, the protective layer and the back layer of the present invention. Examples of hardeners include:
Polyisocyanates described in US Pat. No. 4,281,060 and JP-A-6-208193, epoxy compounds described in US Pat. No. 4,791,042, JP-A-62-890
Vinyl sulfone compounds described in No. 48 and the like are used.

In the present invention, a surfactant may be used for the purpose of improving coatability and charging. As the surfactant, any surfactant such as nonionic, anionic, cationic, and fluorine can be used as appropriate. Specifically,
62-170950, U.S. Pat. No. 5,380,664, and the like, fluoropolymer surfactants, JP-A-60-244945, and JP-A-63
No. 188135, U.S. Patent
No. 3,885,965, etc.
Examples thereof include polyalkylene oxides and anionic surfactants described in JP-A-6-301140.

A hydrazine derivative may be used in the present invention. When a hydrazine derivative is used in the present invention, the compound of the general formula (I) described in Japanese Patent Application No. 6-47961 is used. Specifically, compounds represented by I-1 to I-53 described in the same specification are used.

The following hydrazine derivatives are also preferably used. Compounds represented by (Chemical Formula 1) described in JP-B-6-77138, specifically, compounds described on pages 3 and 4 of the same publication. Compounds represented by the general formula (I) described in JP-B-6-93082, specifically the compounds 1 to 38 described on pages 8 to 18 of the publication. General formula (4) described in JP-A-6-230497, general formula
Compounds represented by (5) and general formula (6), specifically, compounds 4-1 to 4-10, 28 described in pages 25 and 26 of the same publication.
Compounds 5-1 to 5-42 described on pages 36 to 36, and Compounds 6-1 to 6-7 described on pages 39 and 40. Compounds represented by general formulas (1) and (2) described in JP-A-6-289520, specifically, compounds 1-1) described on pages 5 to 7 of the same publication
1-17) and 2-1). (Chemical formula 2) described in JP-A-6-313936
And compounds represented by (Chemical Formula 3).
Compounds described on page 19. A compound represented by (Chemical Formula 1) described in JP-A-6-313951, specifically, pages 3 to 5 of the same.
Compounds described on page. General formula (I) described in JP-A-7-5610
And specifically compounds I-1 to I-38 described on pages 5 to 10 of the same publication. A compound represented by the general formula (II) described in JP-A-7-77783, specifically, pages 10 to 27 of the publication
Compounds II-1 to II-102 described on page. A compound represented by the general formula (H) and the general formula (Ha) described in JP-A-7-104426,
Specifically, compounds H-1 to H-4 described on pages 8 to 15 of the publication
Four. A compound characterized by having an anionic group or a nonionic group forming an intramolecular hydrogen bond with a hydrogen atom of hydrazine in the vicinity of the hydrazine group described in Japanese Patent Application No. 7-191007, and particularly, the compound represented by the general formula (A): Compounds represented by the general formula (B), the general formula (C), the general formula (D), the general formula (E), and the general formula (F), specifically, the compounds N-1 to N-1 described in the publication. N-30. A compound represented by the general formula (1) described in Japanese Patent Application No. 7-191007,
Specifically, compounds D-1 to D-55 described in the publication.

When the hydrazine nucleating agent is used in the present invention, a suitable water-miscible organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide. , Dimethyl sulfoxide,
It can be used by dissolving it in methyl cellosolve or the like.
Further, by a well-known emulsification dispersion method, dibutyl phthalate, tricresyl phosphate, oil such as glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone are dissolved and mechanically emulsified and dispersed. An object can be produced and used. Alternatively, a powder of a hydrazine derivative can be dispersed in water by a ball mill, a colloid mill, or an ultrasonic wave by a method known as a solid dispersion method and used.

When the hydrazine nucleating agent is used in the present invention, it may be added to any of the silver halide emulsion layer on the silver halide emulsion layer side of the support or another hydrophilic colloid layer. Although it is good, it is preferably added to the silver halide emulsion layer or a hydrophilic colloid layer adjacent thereto. The amount of the nucleating agent added in the present invention is preferably 1 to 10 mmol, more preferably 10 to 5 mmol, and most preferably 20 to 5 mmol per mol of silver halide.

Although not required to practice the invention,
It may be advantageous to add a mercury (II) salt as an antifoggant to the emulsion layer. Preferred mercury (II) salts for this purpose are
Mercury acetate and mercury bromide.

Although any support can be used in the present invention, typical supports are:
Polyester film, undercoated polyester film,
Poly (ethylene terephthalate) film, polyethylene naphthalate film, cellulose nitrate film, cellulose ester film, poly (vinyl acetal)
Including films, polycarbonate films and related or resinous materials, as well as glass, paper, metal and the like. Flexible substrates, especially coated with partially acetylated or baryta and / or α-olefin polymers, especially polymers of C2-C10 α-olefins such as polyethylene, polypropylene, ethylene-butene copolymers A coated paper support is typically used. The support may be transparent or opaque, but is preferably transparent.

The photothermographic material of the present invention comprises an antistatic or conductive layer such as a soluble salt (eg chloride,
Nitrate, etc.), a vapor-deposited metal layer, a layer containing an ionic polymer such as those described in U.S. Pat. Good.

As a method for obtaining a color image using the photothermographic material of the present invention, there is a method described in JP-A-7-13295, page 10, left column, line 43 to 11 left column, line 40. Examples of color dye image stabilizers include British Patent No. 1,326,889, U.S. Patent Nos. 3,432,300, 3,698,909, and 3,574,
Nos. 627, 3,573,050, 3,764,337 and 4,042,394.

The photothermographic emulsions of this invention can be coated by a variety of coating operations including dip coating, air knife coating, flow coating or extrusion coating using a hopper of the type described in US Pat. No. 2,681,294. If desired, two or more layers can be coated simultaneously by the methods described in US Pat. No. 2,761,791 and British Patent No. 837,095.

In the heat-developable photographic materials of the present invention, additional layers are included, such as dye-receiving layers for receiving transfer dye images, opacifying layers when reflective printing is desired, protective topcoat layers and photothermographic techniques. Known primer layers and the like can be included. The light-sensitive material of the present invention is preferably capable of forming an image with only one light-sensitive material, and it is preferable that a functional layer necessary for image formation such as an image receiving layer does not serve as another light-sensitive material.

The photothermographic material of the present invention may be thermally developed by any method, but it is usually developed by raising the temperature of the imagewise exposed photosensitive material. The developing temperature is preferably 80 to 250 ° C, more preferably 100 to 140 ° C.
It is. The development time is preferably from 1 to 180 seconds, and from 10 to 180 seconds.
90 seconds is more preferred. The photothermographic material of the present invention may be exposed by any method, but a laser beam is preferable as an exposure light source. The laser light according to the present invention is preferably a gas laser, a YAG laser, a dye laser, a semiconductor laser or the like. Further, a semiconductor laser and a second harmonic generation element can be used.

[0086]

EXAMPLES The present invention will be described below with reference to examples.
The supplementary invention is not limited to these. Example 1 << Preparation of silver halide grains >> 22 g of phthalated gelatin and 30 mg of potassium bromide were dissolved in 700 ml of water and dissolved at a temperature of 35.degree.
After adjusting the pH to 5.0, 159 ml of an aqueous solution containing 18.6 g of silver nitrate
An aqueous solution containing potassium bromide and potassium iodide in a molar ratio of 92: 8 was added over 10 minutes by the control double jet method while keeping the pAg at 7.7. Then, 476 ml of an aqueous solution containing 55.4 g of silver nitrate and 9 potassium dichloride iridate were added.
While maintaining an aqueous solution pAg7.7 containing μmol / liter and potassium bromide at 1 mol / liter, it was added over 30 minutes by the control double jet method. After that, the pH was lowered, the precipitate was aggregated and sedimented, desalted, and 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and pAg8.2 to prepare silver iodobromide grains (iodine content core 8 mol%, average 2 mol%, average The preparation of cubic particles with a size of 0.05 μm, a projected area variation coefficient of 8% and a (100) plane ratio of 87% was completed.

The silver halide grains thus obtained were heated to 60 ° C. and 85 μmol of sodium thiosulfate and
11 μmol of 3,4,5,6-pentafluorophenyldiphenylphosphine selenide, 15 μmol of tellurium compound 1, 3.8 μmol of chloroauric acid and 280 μmol of thiocyanic acid were added,
After ripening for 120 minutes, it was rapidly cooled to 30 ° C. to obtain a silver halide emulsion. << Preparation of Organic Acid Silver Emulsion >> 1.3 g of stearic acid, 0.5 g of arachidic acid, 8.5 g of behenic acid and 300 ml of distilled water were mixed at 90 ° C for 15 minutes, and 31.1 ml of 1N-NaOH aqueous solution was added over 15 minutes while stirring vigorously. After the addition, the temperature was lowered to 30 ° C. Next, 7 ml of a 1N-phosphoric acid aqueous solution was added, and 0.12 g of N-bromosuccinimide was added while stirring more vigorously, and then 2.5 mmol of silver halide grains prepared in advance as silver halide were added. Further, 25 ml of a 1N aqueous solution of silver nitrate was added over 2 minutes, and stirring was continued for 90 minutes. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of the filtrate became 30 μS / cm. To the solid content thus obtained, 37 g of a 1.2 wt% butyl acetate solution of polyvinyl acetate was added and stirred, and the stirring was stopped and the mixture was left to stand to separate the oil layer and the water layer. It was Next, 20 g of a 2.5 wt% 2-butanone solution of polyvinyl butyral (Denka Butyral # 3000-K manufactured by Denki Kagaku Kogyo KK) was added to this oil layer and stirred. Furthermore, pyridinium perbromide bromide 0.12 mmol and calcium bromide dihydrate 0.15 mmol were added together with 0.7 g of methanol, and then 2-butanone 40 g and polyvinyl butyral (Monsanto BUTVAR ^TM B-76) 7.8 were added. Add g and disperse with a homogenizer to obtain an organic acid silver salt emulsion (average minor axis 0.04 μm
, Acicular particles having an average major axis of 1.1 μm and a coefficient of variation of 30%) were obtained.

<< Preparation of Emulsion Layer Coating Solution >> Each chemical was added to the organic acid silver emulsion obtained above in the following amount per mol of silver. 9m sodium phenylthiosulfonate at 25 ℃
g, 72 mg of dye 1, 32 mg of dye 2, 2-mercapto-5-methylbenzimidazole 2.1 g, 4-chlorobenzophenone
-2-Carboxylic acid (Comparative Compound 1) 21.5g and 2-butanone 580
g, 220 g of dimethylformamide were added with stirring.
Left for hours. Next, 8 g of 5-tribromomethylsulfonyl-2-methylthiadiazole, 6.1 g of 2-tribromomethylsulfonylbenzothiazole, 4.8 g of 4,6-ditrichloromethyl-2-phenyltriazine, 2 g of disulfide compound 1 and 1,1 -Bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane 152g, tetrachlorophthalic acid 5g, Megafax F-176P (Dainippon Ink and Chemicals Co., Ltd. fluorine-based surfactant Agent) 1.1 g, 2-butanone 590 g,
10 g of methyl isobutyl ketone were added with stirring.

<< Emulsion side protective layer coating solution >> CAB171-15S (cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.) 75 g, 4-
Methylphthalic acid 5.7g, tetrachlorophthalic anhydride 1.5
g, phthalazine 12.6g, 0.3g Megafax F-176P,
A solution was prepared by dissolving 1.5 g of Sildex H31 (average particle size 3 μm of spherical silica manufactured by Dokai Chemical Industry Co., Ltd.) and 6 g of sumidur N3500 (polyisocyanate manufactured by Sumitomo Bayer Urethane Co., Ltd.) in 3070 g of 2-butanone and 30 g of ethyl acetate.

<< Back Surface Coating Solution >> Calcium compound 1 was synthesized as follows. 0.08 mol of 3,5-di-tert-butylc
0.019 per liter of ethanol solution containing atechol
167 ml of an aqueous solution containing 0.1 mol of calcium chloride and 125 ml of 25% aqueous ammonia were added, and air was blown at room temperature for 3 hours to prepare bis [2- (3,5-di-tert-butyl-o-benzoquinone mono).
imine) -4,6-di-tert-butyl phenolato] Calcium (II)
Was precipitated. 12 g of polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo Co., Ltd.), CAB381-2
0 (Cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.)
12g, 120mg dye 1, 290mg calcium compound 1, 30
0 mg of Dye 2, 5 mg of Dye 3, Sildex H121 (Dokai Chemical Co., Ltd. true spherical silica average size 12 μm) 0.4 g, Sildex H51 (Dokai Chemical Co. Ltd. true spherical silica average size 5 μm)
4g, 0.1g Megafax F-176P, 2g sumidur N3500
Was added to 500 g of 2-butanone and 500 g of 2-propanol with stirring to dissolve and mix.

The emulsion layer coating solution prepared as described above was coated on a 175 μm polyethylene terephthalate support tinted with a blue dye so that the silver content was 2.3 g / m ^2, and then the emulsion layer was coated on the opposite side. The back surface coating solution was applied onto the substrate so that the optical density at 810 nm was 0.7. Further, an emulsion surface protective layer coating solution was coated on the emulsion surface so that the dry thickness was 2 μm, to obtain a light-sensitive material 1-01. In addition, one containing no comparative compound, one containing equimolar benzoic acid (comparative compound 2) and compounds 6, 9, 13, 16, 19, 35, 55 in place of comparative compound 1 were used as photosensitive materials 1. -02 to 10. The smoothness of the thus-obtained light-sensitive materials (the Beck's smoothness was examined by using the Oken type smoothness measurement described in J.TAPPI Paper Pulp Test Method No. 5) was the emulsion surface.
It was 820 seconds and the back side was 80 seconds.

[0092]

Embedded image

(Evaluation of Photographic Performance) After exposing the photographic material with a laser sensitometer equipped with a 820 nm diode, the photographic material was processed (developed) at 120 ° C. for 15 seconds, and the obtained image was evaluated by a densitometer. It was The measurement result is Dmin, sensitivity (Dmi
(the reciprocal of the ratio of the exposure amount giving a density higher by 1.0 than n). Sensitivity was expressed as a relative value with Sensitive Material 1-03 set to 100.

(Evaluation of storability with time) Each sample processed in the same manner as the transportability evaluation was left for 1 day under the condition of 25 ° C-50% RH, and 10 sheets of each photographic material were placed in a bag made of moisture-proof material. Then, put it in a 35.1 cm × 26.9 cm × 3.0 cm cosmetic box and
The sample was aged at 5 ° C for 5 days (forced aging). The same treatment as that used for evaluation of photographic properties was performed on this sample and a sample prepared in the same manner as in forced aging except that the storage temperature was 4 ° C. for comparison, and the density of the fog portion was measured. The natural aging property was evaluated as a fog increase rate. (Fog increase rate) = [[(fog of sample after forced aging)-(fog of comparative sample)] / [(maximum density of comparative sample)-(support density)] x 100 Is good.

(Evaluation of Preservability of Light-Irradiated Image) The photosensitive material which was exposed and developed in the same manner as in the evaluation of photographic property was attached to the inside of a glass window exposed to direct sunlight and left standing for 1 month, and the appearance of the image was visually evaluated according to the following criteria. did. ◎ ... There is almost no change. ○: There is a slight change in color tone, but it does not bother me. Δ: Practically acceptable although there is discoloration in the image area. ×: Dmin is discolored and the density cannot be increased.

The results are shown in Table 1. High feeling in the field of the present invention,
A good light-sensitive material having low fog and good storage stability was obtained.

[0097]

[Table 1]

Example 2 << Preparation of Organic Acid Silver Emulsion >> Behenic acid 840 g, Stearic acid 95
g was added to 12 liters of water, and while maintaining the temperature at 90 ° C., a solution prepared by dissolving 48 g of sodium hydroxide and 63 g of sodium carbonate in 1.5 liters of water was added. After stirring for 30 minutes, the temperature was raised to 50 ° C., 1.1 L of a 1% aqueous solution of N-bromosuccinimide was added, and then 2.3 L of a 17% aqueous solution of silver nitrate was gradually added with stirring. Further, the liquid temperature was set to 35 ° C., 1.5 liters of a 2% aqueous solution of potassium bromide was added with stirring over 2 minutes and then stirred for 30 minutes, and 2.5 liters of a 1% aqueous solution of N-bromosuccinimide was added. 1.2% by weight of polyvinyl acetate in butyl acetate solution 3300 g with stirring in this aqueous mixture
Was added and left standing for 10 minutes to separate into two layers, the aqueous layer was removed, and the remaining gel was washed twice with water. The gel-like mixture of behenic acid / silver stearate and silver bromide thus obtained was dispersed in 1800 g of a 2.6% isopropyl alcohol solution of polyvinyl butyral (Denka butyral # 3000-K manufactured by Denki Kagaku Kogyo Co., Ltd.), and further dispersed in polyvinyl. Butyral (Denka Butyral # 4000-, manufactured by Denki Kagaku Kogyo Co., Ltd.)
2) 600 g and 300 g of isopropyl alcohol were dispersed to obtain an organic acid silver salt emulsion (acicular grains having an average minor axis of 0.05 μm, an average major axis of 1.4 μm and a coefficient of variation of 26%).

<< Preparation of Emulsion Layer Coating Solution >> Each chemical was added to the organic acid silver emulsion obtained above in the following amount per mol of silver. Sodium phenylthiosulfonate 10 at 25 ° C
mg, 69 mg of dye a, 2-mercapto-5-methylbenzimidazole 2 g, 4-chlorobenzophenone-2-carboxylic acid (Comparative Compound 1) 21.5 g, 2-butanone 580 g, and dimethylformamide 220 g were added with stirring. Left for hours. Then, 5-tribromomethylsulfonyl-2-methylthiadiazole 8 g, 2-tribromomethylsulfonylbenzothiazole 6 g, 4,6-ditrichloromethyl-2-phenyltriazine 5.1 g, disulfide compound a 2 g, 1,1- Screw (2
-Hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane 180g, tetrachlorophthalic acid 5.5g, 3g hydrazine derivative a, Megafax F-176P (Dainippon Ink and Chemicals Co., Ltd. fluorine 1.1 g of a system surfactant), 590 g of 2-butanone, and 10 g of methyl isobutyl ketone were added with stirring.

<< Emulsion surface protective layer coating solution >> 75 g of CAB171-15S (cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.), 4-
Methylphthalic acid 5.7g, tetrachlorophthalic anhydride 1.5
g, phthalazine 14g, 0.3g of Megafax F-176P, Sildex H31 (Doikai Chemical Co., Ltd. spherical silica average size 3
μm) 2 g, sumidur N3500 (Sumitomo Bayer Urethane Polyisocyanate) 7.2 g to 2-butanone 3070 g and ethyl acetate
A 30 g solution was prepared.

<< Preparation of Support Having Back Surface >> Polyvinyl butyral (Denka Butyral # 4000-2 manufactured by Denki Kagaku Kogyo Co., Ltd.) 6 g, Sildex H121 (spherical silica average size 12 μm manufactured by Dokai Chemical Co., Ltd.) 0.2 g, Sildex H51 (spherical silica having an average size of 5 μm, manufactured by Dokai Chemical Industry Co., Ltd.) 0.2 g and 0.1 g of Megafax F-176P were added to 64 g of 2-propanol with stirring to dissolve and mix. In addition, 400 mg of Dye 1
A solution of 10 g of methanol and 20 g of acetone and a solution of 1 g of 3-isocyanatomethyl-3,5,5-trimethylhexyl isocyanate in 7 g of ethyl acetate were added to prepare a coating solution.
63 back side coating liquid on polyethylene terephthalate film consisting of moisture-proof undercoat containing vinylidene chloride on both sides
Coating was performed so that the optical density at 3 nm was 0.7.

After coating the emulsion layer coating solution on the support prepared as described above so that the silver content was 2 g / m ² , the emulsion surface protective layer coating solution was dried on the emulsion surface to a dry thickness of 2 μm. A photosensitive material 2-01 was obtained by coating. The light-sensitive materials 2-02 to 06 were prepared by using equimolar amounts of the compounds 13, 16, 20 and the comparative compound 3 and p-cyanobenzoic acid (comparative compound 4) instead of the comparative compound 1.

[0103]

Embedded image

(Evaluation of Photographic Performance of Photosensitive Material) After exposing the photographic material with a 633 nm He-Ne laser sensitometer, the photographic material was exposed at 115 ° C.
Processed (developed) for 25 seconds. Further, the developed material was exposed to a halogen lamp for 15 seconds to erase the dye in the back layer. The image thus obtained was evaluated by a densitometer. The results of the measurement were evaluated in terms of Dmin and sensitivity (the reciprocal of the ratio of the exposure amount giving a density 3.0 higher than Dmin). In addition, the characteristic curve
The slope of the straight line connecting the points 0.3 and 3.0 is shown as the gradation γ. The sensitivity was expressed as a relative value with the photosensitive material 2-01 being 100.

The optical image storability was evaluated in the same manner as in Example 1. Table 2 shows the results. In the range of the present invention, a light-sensitive material having high feeling, low fog and good storability was obtained.

[0106]

[Table 2]

[0107]

According to the present invention, high feeling, low fog, high contrast,
In addition, a photosensitive material having good preservability and excellent surface condition was obtained.

Claims (3)

[Claims] 1. A photothermographic material comprising a photosensitive silver halide grain on at least one side of which a compound represented by formula (I) is contained. General formula (I) (In the formula, Y represents a carbamoyl group, an acylamino group, a ureido group, a sulfamoyl group or a sulfonylamino group. L represents a divalent hydrocarbon group. M represents a hydrogen atom or a cation.) 2. A photothermographic material comprising at least one of a support, a binder, an organic silver salt, a reducing agent for silver ions, and photosensitive silver halide grains, wherein the compound represented by formula (I) is used. A photothermographic material characterized by containing. General formula (I) (In the formula, Y represents a carbamoyl group, an acylamino group, a ureido group, a sulfamoyl group or a sulfonylamino group. L represents a divalent hydrocarbon group. M represents a hydrogen atom or a cation.) 3. A photothermographic material according to claim 1, wherein the compound represented by the general formula (I) is a compound represented by the general formula (IA). General formula (IA) embedded image (In the formula, M represents a hydrogen atom or a cation. Ra and Rb are
Each represents a hydrogen atom, an aliphatic hydrocarbon group, an aryl group, a heterocyclic group or a hydroxy group. n represents an integer of 0 to 4. )