JPH112880A - Heat-developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a good silver tone and photographic characteristics in development and superior stability in exposure and before and after development by spectrally sensitizing photosensitive silver halide with a specified methine dye. SOLUTION: The photosensitive silver halide is contained in a photosensitive layer using a polymer latex as a main binder and it is spectrally sensitized by the methine dye represented by formula I or II in which each of Z1 -Z6 is an atomic group necessary to form a 5- or 6-membered N-containing hetero ring; each of R1 and R3 is an alkyl group; R2 is an H atom or a substituent; each of L1 -L9 is a methine group; each of Z4 and Z6 is an atomic group necessary to form a 5- or 6-membered N-containing hetero ring; R4 is an alkyl group; each of R5 and R6 is an H atom or a substituent; each of L10 -L15 is a methine group; each of M1 and M2 is a charge ballasting counter ion; and each of m1 and m2 is an integer of >=0 necessary to neutralize the intramolecular charge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable photosensitive material, and more particularly to a photosensitive material for a laser imagesetter or a laser imager (hereinafter referred to as an LI photosensitive material). LI that can obtain high-sharp image quality and therefore faithfully reproduce image information
The present invention relates to a photothermographic material including a photosensitive material.

[0002]

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

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

A method of forming an image by thermal development is described in, for example, US Pat. Nos. 3,152,904 and 3,457,075.
No. and D. Morgan and B.A. Shelly
ly) “Thermal processed silver system (Therma
lly Processed Silver Systems) A "(Imaging
Processings and Materials (Imaging Proce
sses and Materials) Neblette 8th edition, Sturgi (Stur
ge), V.I. Walworth, A .; Shep
(Shepp), ed., Page 2, 1969). Such photosensitive materials are prepared by dispersing a reducible non-photosensitive silver source (eg, an organic silver salt), a catalytically active amount of a photocatalyst (eg, silver halide), and a silver reducing agent, usually in an organic binder matrix. It is contained in. The photosensitive material is stable at normal temperature, but when heated to a high temperature (for example, 80 ° C. or higher) after exposure, silver is reduced through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and a reducing agent. Generate This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure. The silver formed by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image.

Conventionally, photothermographic materials of this type have been known, but most of these photosensitive materials are prepared by applying a coating solution using an organic solvent such as toluene, methyl ethyl ketone (MEK) or methanol as a solvent. A photosensitive layer is formed. The use of an organic solvent as a solvent is disadvantageous not only in adverse effects on the human body in the manufacturing process but also in cost due to recovery of the solvent and the like.

Therefore, a method of forming a photosensitive layer (hereinafter, also referred to as "aqueous photosensitive layer") using a coating solution of a water solvent which does not have such a concern has been considered. For example, JP-A-49-52626, JP-A-53-116144, and the like describe examples using gelatin as a binder.
JP-A-50-151138 discloses an example in which polyvinyl alcohol is used as a binder.

Japanese Patent Application Laid-Open No. 60-61747 discloses an example in which gelatin and polyvinyl alcohol are used in combination. As another example, JP-A-58-28737 describes an example of a photosensitive layer using water-soluble polyvinyl acetal as a binder.

Certainly, when such a binder is used, the photosensitive layer can be formed using a coating solution of an aqueous solvent, and the advantages in terms of environment and cost are great.

However, when a polymer such as gelatin, polyvinyl alcohol, or water-soluble polyacetal is used as a binder, the compatibility with the organic silver salt is poor, and not only a coated material which can be practically used due to the coated surface quality cannot be obtained, but also
Only those that have significantly impaired commercial value, such as brown or yellow whose silver tone in the developed part is far from black which is originally preferred, and low blackening density in the exposed part and high density in the unexposed part, etc. Did not.

Therefore, a water-based photographic material excellent in environmental and cost aspects, having a good coated surface quality, a good silver tone at the time of development, and a sufficient photographic performance, and a stable before and after exposure and development. There has been a demand for a technique for providing a photothermographic material having excellent heat resistance.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photothermographic material which has a good silver tone and photographic characteristics at the time of development, and has excellent stability before and after exposure and development. .

[0012]

The object of the present invention has been achieved by the following means as a result of intensive studies. (1) In a photothermographic material having a photosensitive silver halide, a non-photosensitive organic silver salt and a binder on at least one surface of a support, the photosensitive silver halide is represented by the following general formula (I) or A photothermographic material which has been spectrally sensitized by a methine dye represented by the general formula (II) and wherein a main binder of a photosensitive layer containing a photosensitive silver halide is a polymer latex. General formula (I)

[0013]

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In the general formula (I), Z ₁ , Z ₂ and Z ₃ are 5
Or, it represents a group of atoms necessary for forming a 6-membered nitrogen-containing heterocyclic ring. R ₁ and R ₃ represent an alkyl group, and R ₂ represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group. _{L 1, L 2, L 3} , L 4, L 5, L 6, L 7, L 8
And L ₉ represents a methine group. p ₁ and p ₂ represent 0 or 1. n ₁ and n ₂ are 0, 1, ₂ , 3 or 4
Represents M ₁ represents a charge balancing counter ion, and m ₁ represents a number of 0 or more necessary to neutralize the charge of the molecule. General formula (II)

[0015]

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In the general formula (II), Z ₄ , Z ₅ and Z ₆ are 5
Or, it represents a group of atoms necessary for forming a 6-membered nitrogen-containing heterocyclic ring. R ₄ represents an alkyl group, and R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group. L ₁₀ , L ₁₁ , L ₁₂ , L ₁₃ , L ₁₄ and L ₁₅ represent a methine group. p ₃ is 0 or 1. n ₃ and n ₄ represent 0, 1, 2, 3 or 4. M ₂ represents a charge balancing counter ion, and m ₂ represents a number of 0 or more necessary to neutralize the charge of the molecule. (2) In the general formula (I), R ₁ , R ₂ , R
_{3, Z 1, Z 2,} Z 3, L 1, L 2, L 3, L 4, L
_At least one of ₅ , L ₆ , L ₇ , L ₈ and L ₉ has a thioether group, and in the general formula (II),
_{4, R 5, R 6,} Z 4, Z 5, Z 6, L 10, L 11,
The photothermographic material according to the above (1), wherein at least one of L ₁₂ , L ₁₃ , L ₁₄ and L ₁₅ has a thioether group. (3) In the general formula (I), R ₁ , R ₂ , R
_At least one of ₃ , Z ₁ , Z ₂ or Z ₃ has a thioether group, and in the general formula (II), R ₄ , R
_{5. The} photothermographic material according to (1), wherein at least one of ₅ , R ₆ , Z ₄ , Z ₅ and Z ₆ has a thioether group. (4) The thermal development according to the above (2) or (3), wherein in the methine dyes represented by the general formulas (I) and (II), the heterocyclic ring having a thioether group is other than a quinoline nucleus or a pyridine nucleus. Photosensitive material. (5) The photothermographic material according to the above (1), wherein the methine dye represented by the general formula (I) is represented by the following general formula (III). General formula (III)

[0017]

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In the formula (III), Z ₇ has the same meaning as Z ₁ , Z ₈ has the same meaning as Z _2, and Z ₉ is a sulfur atom, a selenium atom or an oxygen atom. R ₇ has the same meaning as R ₁ , R ₅ has the same meaning as R ₂ , R ₉
Has the same meaning as R ₃ . L ₁₆ is L ₁ as defined, L ₁₇ is L ₂ synonymous, L ₁₈ is L ₃ synonymous, L ₁₉ is L ₄ synonymous, L ₂₀ is L
₅ synonymous, L ₂₁ is L ₆ synonymous, L ₂₂ has the same meaning as L _7. p ₄ is p ₁ synonymous, n ₅ is n ₁ synonymous, n ₆ is n ₂
And M ₃ has the same meaning as M _1, and m ₃ has the same meaning as m ₁ .
Q is an alkyl group, an aryl group, or a heterocyclic group.
k ₁ is 1, 2, 3 or 4. (6) The polymer of the polymer latex is 25 ° C.
The photothermographic material according to any one of the above (1) to (5), wherein the equilibrium water content at 60% RH is 2% by weight or less. (7) The photothermographic material according to any one of the above (1) to (6), having a water-resistant protective layer formed on the photosensitive layer using a hydrophilic polymer or an aqueous emulsion. (8) The method according to any one of the above (1) to (7), wherein a photosensitive silver halide to which a methine dye represented by the general formula (I) or (II) is added in advance when preparing a coating solution. Photothermographic material.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The photothermographic material of the present invention contains a photosensitive silver halide, which is represented by the general formula (I) or (I).
It is spectrally sensitized by the methine dye represented by I). In the methine dye represented by the general formula (I),
The methine dye represented by the general formula (III) is particularly preferred.

In the general formulas (I), (II) and (III), the 5- or 6-membered nitrogen-containing heterocyclic ring represented by Z ₁ , Z ₃ , Z ₄ and Z ₇ includes a thiazoline nucleus and a thiazole nucleus. Benzothiazole nucleus, oxazoline nucleus, oxazole nucleus, benzoxazole nucleus, selenazoline nucleus, selenazole nucleus, 3,3-dialkylindolenine nucleus (for example, 3,3-dimethylindolenine), imidazoline nucleus, imidazole nucleus , Benzimidazole nucleus, 2-pyridine nucleus, 4-pyridine nucleus, 2-quinoline nucleus, 4-quinoline nucleus, 1-isoquinoline nucleus, 3-isoquinoline nucleus, imidazo [4,5-b] quinoxaline nucleus, oxadiazole nucleus , A thiadiazole nucleus, a tetrazole nucleus, and a pyrimidine nucleus.

Preferred are benzoxazole nucleus, thiazole nucleus, benzothiazole nucleus, benzoselenazole nucleus and benzimidazole nucleus, more preferably benzoxazole nucleus, thiazole nucleus and benzothiazole nucleus, particularly preferably benzothiazole nucleus. It is. The heterocyclic ring substituted by the thioether group, which is a preferable substituent in the present invention, is preferably a heterocyclic ring excluding the pyridine nucleus and the quinoline nucleus.

Assuming that the substituent on Z ₁ , Z ₃ , Z ₄ and Z ₇ is V, the substituent represented by V is not particularly limited. For example, a halogen atom (eg, chlorine, bromine, iodine, fluorine, etc.) ), Mercapto group, cyano group, carboxyl group, phosphate group, sulfo group, hydroxy group, carbamoyl group (hereinafter, “carbamoyl group” is used in the meaning of carbamoyl group which may have a substituent) A carbamoyl group having 1 to 10, preferably 2 to 8 carbon atoms, more preferably 2 to 5 carbon atoms (eg, methylcarbamoyl, ethylcarbamoyl, morpholinocarbonyl);
Sulfamoyl group (which may be substituted), for example, a sulfamoyl group having 0 to 10, preferably 2 to 8, and more preferably 2 to 5 carbon atoms (eg, methylsulfamoyl, ethylsulfamoyl, piperidi Nosulfamoyl), nitro group, alkoxy group (optionally substituted), for example, an alkoxy group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms (eg, methoxy, ethoxy, 2-methoxyethoxy, 2-phenylethoxy), an aryloxy group (optionally substituted), for example, an aryloxy group having 6 to 20, preferably 6 to 12, more preferably 6 to 10 carbon atoms (eg, phenoxy , P-methylphenoxy, p-chlorophenoxy, naphthoxy),

Acyl group (optionally substituted), for example, an acyl group having 1 to 20, preferably 2 to 12, more preferably 2 to 8 carbon atoms (eg, acetyl, benzoyl, trichloroacetyl), acyloxy A group (optionally substituted), for example, having 1 to 20 carbon atoms, preferably 2 to 12 carbon atoms, and more preferably 2 carbon atoms
To 8 acyloxy groups (eg, acetyloxy, benzoyloxy), acylamino groups (optionally substituted)
For example, it has 1 to 20 carbon atoms, preferably 2 to 1 carbon atoms.
2, more preferably an acylamino group having 2 to 8 carbon atoms (eg, acetylamino), a sulfonyl group (which may be substituted), for example, 1 to 20 carbon atoms, preferably 1 carbon atom
To 10, more preferably a sulfonyl group having 1 to 8 carbon atoms (for example, methanesulfonyl, ethanesulfonyl, benzenesulfonyl, etc.), a sulfinyl group (which may be substituted), for example, 1 to 20 carbon atoms, preferably 1 carbon atom
To 10, more preferably a sulfinyl group having 1 to 8 carbon atoms (eg, methanesulfinyl, benzenesulfinyl), a sulfonylamino group (optionally substituted), for example, 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms,
More preferably, a sulfonylamino group having 1 to 8 carbon atoms (eg, methanesulfonylamino, ethanesulfonylamino, benzenesulfonylamino, etc.),

Amino group, substituted amino group (optionally substituted), for example, an amino group having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms (eg, methylamino, dimethylamino, Benzylamino,
Anilino, diphenylamino), ammonium group (optionally substituted), for example, an ammonium group having 0 to 15, preferably 3 to 10, more preferably 3 to 6 carbon atoms (eg, a trimethylammonium group, a triethylammonium group) Hydrazino group (optionally substituted), for example, a hydrazino group having 0 to 15, preferably 1 to 10, more preferably 1 to 6 carbon atoms (eg, a trimethylhydrazino group), a ureido group ( (It may be substituted.) For example, a ureido group having 1 to 15 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms (eg, ureide group, N, N-dimethylureide group), imide group ( May be substituted) for example, having 1 to 15 carbon atoms, preferably 1 to 10 carbon atoms,
More preferably, an imide group having 1 to 6 carbon atoms (for example, succinimide group), an alkyl or arylthio group (which may be substituted), for example, 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, and more preferably 1 carbon atom From 8
Alkyl, arylthio, heterocyclylthio groups (e.g., methylthio, ethylthio, carboxyethylthio,
Sulfobutylthio, phenylthio, 2-pyridylthio, etc.), alkoxycarbonyl group (optionally substituted), for example, having 2 to 20 carbon atoms, preferably 2 to 1 carbon atoms
2, more preferably an alkoxycarbonyl group having 2 to 8 carbon atoms (for example, methoxycarbonyl, ethoxycarbonyl, benzyloxycarbonyl), an aryloxycarbonyl group (which may be substituted), for example, having 6 to 2 carbon atoms
0, preferably an aryloxycarbonyl group having 6 to 12 carbon atoms, more preferably 6 to 8 carbon atoms (eg, phenoxycarbonyl);

An alkyl group (optionally substituted)
An unsubstituted alkyl group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms (eg, methyl, ethyl, propyl, butyl), and 1 to 18 carbon atoms, preferably 1 carbon atom To 10, more preferably a substituted alkyl group having 1 to 5 carbon atoms (hydroxymethyl, trifluoromethyl, benzyl, carboxyethyl, ethoxycarbonylmethyl, acetylaminomethyl, and also preferably, having 2 to 18 carbon atoms, more preferably Is 3 to 10 carbon atoms, particularly preferably 3 carbon atoms
To 5 unsaturated hydrocarbon groups (for example, a substituted alkyl group also includes a vinyl group, an ethynyl group, a 1-cyclohexenyl group, a benzylidine group, and a benzylidene group);
Aryl group (optionally substituted), for example, a substituted or unsubstituted aryl group having 6 to 20, preferably 6 to 15, more preferably 6 to 10 carbon atoms (eg, phenyl, naphthyl, p-carboxyphenyl, p-nitrophenyl, 3,5-dichlorophenyl, p-cyanophenyl, m-fluorophenyl, p-tolyl),

Heterocyclic group (optionally substituted) For example, an optionally substituted heterocyclic group having 1 to 20 carbon atoms, preferably 2 to 10 carbon atoms, more preferably 4 to 6 carbon atoms (eg, pyridyl, 5-methylpyridyl, thienyl, furyl, morpholino, tetrahydrofurfuryl). Further, a structure in which a benzene ring, a naphthalene ring, or an anthracene ring is condensed can be employed.

Further, V may be further substituted on these substituents.

Preferred are the above-mentioned alkyl groups, aryl groups, alkoxy groups, alkylthio groups, halogen atoms,
Acyl group, cyano group, sulfonyl group and benzene ring condensation, more preferably alkyl group, aryl group,
An alkylthio group, a halogen atom, an acyl group, a sulfonyl group and a benzene ring condensation are preferred, and a methyl group, a phenyl group, a methoxy group, a methylthio group, a chlorine atom, a bromine atom, an iodine atom and a benzene ring condensation are particularly preferred.

Most preferred are phenyl, methylthio, chlorine, bromine, iodine and benzene ring condensation.

L ₁ , L ₂ , L ₈ , L ₉ , L ₁₀ , L ₁₁ , L
_The methine groups represented by ₁₆ and L ₁₇ may have a substituent, and examples of the substituent include the substituents represented by V described above. Preferably it is an unsubstituted methine group.

P ₁ , p ₂ , p ₃ and p ₄ are 0 or 1
And preferably 0.

Z ₉ represents a sulfur atom, a selenium atom and an oxygen atom, and is preferably a sulfur atom or an oxygen atom;
More preferably, it is a sulfur atom.

Z ₆ represents a group of atoms necessary for forming an acidic nucleus, and can take the form of an acidic nucleus of any general merocyanine dye. The acidic nucleus referred to here is, for example, “The Theory of Japan” edited by James.
The Photographic Process "(The The
ory of the Photographic Pr
ocess) 4th edition, Macmillan Publishing Co., 1977,
198 pages. Specifically, US Pat.
567719, 3575869, 380463
No. 4, No. 3837862, No. 40028080, No. 4
925777 and JP-A-3-167546.

The acidic nucleus is preferred when it forms a 5- or 6-membered nitrogen-containing heterocycle consisting of carbon, nitrogen and chalcogen (typically oxygen, sulfur, selenium and tellurium) atoms, and includes the following nuclei: .

2-pyrazolin-5-one, pyrazolidin-3,5-dione, imidazolin-5-one, hydantoin, 2- or 4-thiohydantoin, 2-iminooxazolidin-4-one, 2-oxazoline-5-one ,
2-thiooxazoline-2,4-dione, isoxazolin-5-one, 2-thiazolin-4-one, thiazolidine-4-one, thiazolidine-2,4-dione, rhodanine, thiazolidine-2,4-dithione, Isorhodanine, indan-1,3-dione, thiophen-3-one, thiophen-3-one-1,1-dioxide, indoline-2-one, indoline-3-one, 2-oxoindazolinium, 3-oxo Indazolinium, 5,
7-dioxo-6,7-dihydrothiazolo [3,2-
a] pyrimidine, cyclohexane-1,3-dione,
3,4-dihydroisoquinolin-4-one, 1,3-dioxane-4,6-dione, barbituric acid, 2-thiobarbituric acid, chroman-2,4-dione, indazolin-2-one, pyrido [ 1,2-a] pyrimidine-
1,3-dione, pyrazolo [1,5-b] quinazolone,
Pyrazolo [1,5-a] benzimidazole, pyrazolopyridone, 1,2,3,4-tetetrahydroquinoline-
2,4-dione, 3-oxo-2,3-dihydrobenzo [d] thiophene-1,1-dioxide, 3-dicyanomethine-2,3-dihydrobenzo [d] thiophene-
The core of 1,1-dioxide.

Z ₆ is preferably hydantoin, 2 or 4-thiohydantoin, 2-oxazoline-5-one, 2-thiooxazoline-2,4-dione, thiazolidine-2,4-dione, rhodanine, thiazolidine-.
2,4-dithione, barbituric acid, and 2-thiobarbituric acid, and more preferably, hydantoin, 2 or 4-thiohydantoin, 2-oxazolin-5-one, rhodanine, barbituric acid, and 2-thiobarbitic acid. Tool acid. Particularly preferred are 2 or 4-thiohydantoin, 2-oxazolin-5-one and rhodanine.

The 5- or 6-membered nitrogen-containing heterocyclic ring formed by Z ₂ , Z ₅ and Z ₈ is a heterocyclic ring represented by Z ₆ except for an oxo group or a thioxo group. Preferably, hydantoin, 2 or 4-thiohydantoin, 2-oxazolin-5-one, 2-thiooxazoline-2,4-dione, thiazolidine-2,4-dione, rhodanine, thiazolidine-2,4-dithione,
Barbituric acid or 2-thiobarbituric acid obtained by removing an oxo group or a thioxo group, more preferably hydantoin, 2 or 4-thiohydantoin,
-Oxazolin-5-one, rhodanine, barbituric acid, 2-thiobarbituric acid with the oxo group or thioxo group removed, particularly preferably 2 or 4-
It is obtained by removing an oxo group or a thioxo group from thiohydantoin, 2-oxazolin-5-one or rhodanine.

R ₁ , R ₃ , R ₄ , R ₇ and R ₉ each represent an alkyl group, for example, carbon atoms 1 to 18,
Preferably from 1 to 7, particularly preferably from 1 to 4, unsubstituted alkyl groups (for example methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl,
Dodecyl, octadecyl), a substituted alkyl group having 1 to 18, preferably 1 to 7, and particularly preferably 1 to 4 carbon atoms, for example, a heterocyclic group substituted by V mentioned as a substituent such as Z ₁ described above. . Preferably, an aralkyl group (eg, benzyl, 2-phenylethyl), an unsaturated hydrocarbon group (eg, an allyl group), a hydroxyalkyl group (eg, 2-hydroxyethyl, 3-hydroxypropyl), a carboxyalkyl group (eg, 2-carboxyethyl) , 3-carboxypropyl, 4-carboxybutyl, carboxymethyl), an alkoxyalkyl group (eg, 2-methoxyethyl, 2- (2-methoxyethoxy) ethyl), an aryloxyalkyl group (eg, 2-phenoxyethyl, 2- (1-naphthoxy) ethyl), an alkylthioalkyl group (eg, 2-methylthioethyl, 2- (2-methylthioethylthio) ethyl), an arylthioalkyl group (eg, 2-phenylthioethyl,
2- (1-naphthylthio) ethyl), heterocyclylthioalkyl group (for example, 2-pyridylthioethyl, 2-thienylthioethyl), alkoxycarbonylalkyl group (for example, ethoxycabonylmethyl, 2-benzyloxycarbonylethyl), aryloxy Carbonylalkyl group (eg, 3-phenoxycarbonylpropyl), acyloxyalkyl group (eg, 2-acetyloxyethyl), acylalkyl group (eg, 2-acetylethyl), carbamoylalkyl group (eg, 2-morpholinocarbonylethyl), sulfamoyl Alkyl group (for example, N, N-dimethylcarbamoylmethyl), sulfoalkyl group (for example, 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2- [3-
Sulfopropoxy] ethyl, 2-hydroxy-3-sulfopropyl, 3-sulfopropoxyethoxyethyl),
A sulfoalkenyl group (for example, a sulfopropenyl group),
Sulfatoalkyl group (for example, 2-sulfatoethyl group, 3-sulfatopropyl, 4-sulfatobutyl)
Heterocyclic-substituted alkyl groups (for example, 2- (pyrrolidine-2-
On-1-yl) ethyl, tetrahydrofurfuryl),
Alkylsulfonylcarbamoylmethyl group (for example, methanesulfonylcarbamoylmethyl group)}.

Preferred are the above-mentioned carboxyalkyl, sulfoalkyl, sulfoalkenyl, unsubstituted alkyl, alkylthioalkyl, arylthioalkyl and heterocyclylthioalkyl groups.

Examples of the alkyl group represented by R ₂ , R ₅ , R ₆ and R ₈ include the unsubstituted alkyl group and the substituted alkyl group mentioned as examples of R ₁ and the like, and similar ones are preferable. . Moreover, it has 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms, and more preferably 6 to 8 carbon atoms.
An unsubstituted aryl group (for example, a phenyl group or a 1-naphthyl group) having 6 to 10 carbon atoms, preferably 6 to 1 carbon atoms
0, more preferably an aryl group V is substituted cited as substituents, such as Z ₁ of the substituted aryl group (e.g., above 8 to 6 carbon atoms. Specifically p- methoxyphenyl group, p- methyl Phenyl group, p-chlorophenyl group, etc.), unsubstituted heterocyclic group having 1 to 20 carbon atoms, preferably 3 to 10 carbon atoms, more preferably 4 to 8 carbon atoms (for example, 2-furyl group, 2 -Thienyl group, 2-pyridyl group, 3-pyrazolyl, 3-isoxazolyl, 3-isothiazolyl, 2-imidazolyl,
-Oxazolyl, 2-thiazolyl, 2-pyridazyl, 2
-Pyrimidyl, 3-pyrazyl, 2- (1,3,5-triazolyl), 3- (1,2,4-triazolyl), 5-
Tetrazolyl), 5-tetrazolyl), having 1 to 2 carbon atoms
0, preferably from 3 to 10 carbon atoms, more preferably include heterocyclic group V mentioned as substituents such as Z ₁ substituted Hajime Tamaki (e.g., the aforementioned 8 from 4 carbon atoms is substituted. Specifically Represents a 5-methyl-2-thienyl group, a 4-methoxy-2-pyridyl group, etc.).

Preferred as R ₂ , R ₅ , R ₆ and R ₈ are methyl, ethyl, 2-sulfoethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, carboxymethyl, 2-methylthioethyl, 2-phenyl Thioethyl, phenyl, 2-pyridyl and 2-thiazolyl.

L ₃ , L ₄ , L ₅ , L ₆ , L ₇ , L ₁₂ , L
₁₃ represents _{L 14, L 15, L 18} , L 19, L 20, L 21 and L ₂₂ each independently represents a methine group. These methine groups may have a substituent, for example, a substituted or unsubstituted C 1 to C 15, preferably C 1
To 10, more preferably a C1 to C5 alkyl group (methyl, ethyl, 2-carboxyethyl) substituted or unsubstituted C6 to C20, preferably C6 to C15, more preferably C6 to C15 10 aryl groups (eg, phenyl, o-carboxyphenyl) substituted or unsubstituted having 3 to 20 carbon atoms, preferably 4 carbon atoms
To 15, more preferably a C6 to C10 heterocyclic group (e.g., N, N-, diethylbarbituric acid group), a halogen atom (e.g., chlorine, bromine, fluorine, iodine), and a C1 to C15, preferably C1 to C10, more preferably C1 to C5 alkoxy group (for example, methoxy, ethoxy), C1 to C15, preferably C1 to C10, more preferably C1 to C5 alkylthio group ( For example, methylthio, ethylthio), carbon number 6
To 20, preferably an arylthio group having 6 to 15 carbon atoms, more preferably 6 to 10 carbon atoms (eg phenylthio), 0 to 15 carbon atoms, preferably 2 to 10 carbon atoms, more preferably 4 to 10 carbon atoms. Amino acids (eg, N, N-diphenylamino, N-methyl-
N-phenylamino, N-methylpiperazino) and the like. It may also form a ring with other methine groups, or Z ₁ , Z ₃ , Z ₄ , Z ₇ , R ₁ , R ₃ , R ₄ , R
_A ring can also be formed with ₇ and R ₉ .

N ₁ , n ₂ , n ₃ , n ₄ , n ₅ , n ₆ are:
0, 1, 2, 3, 4 are represented. n ₁ , n ₃ and n ₅ are preferably 0, 1, 2, and 3, more preferably 0 and 1, and particularly preferably 1. n ₂ , n ₄ ,
n ₆ is preferably 0, 1, 2, or 3, more preferably 0 or 1, and particularly preferably 0.

N ₁ , n ₂ , n ₃ , n ₄ , n ₅ and n ₆ are 2
At this point, the methine groups are repeated but need not be the same.

M ₁ , M ₂ and M ₃ are included in the formula to indicate the presence of a cation or an anion when necessary to neutralize the ionic charge of the dye. Typical cations include inorganic cations such as hydrogen ion (H ⁺ ), alkali metal ions (eg, sodium ion, potassium ion, lithium ion), alkaline earth metal ions (eg, calcium ion), and ammonium ions (eg, Organic ions such as ammonium ion, tetraalkylammonium ion, pyridinium ion, and ethylpyridinium ion. The anion may be either an inorganic anion or an organic anion, such as a halogen anion (for example, a fluorine ion, a chloride ion, an iodine ion), a substituted arylsulfonic acid ion (p-toluenesulfonic acid ion, p-chlorobenzene ion). Sulfonate ion), aryl disulfonic acid ion (for example, 1,3-benzenesulfonic acid ion,
1,5-naphthalenedisulfonic acid ion, 2,6-naphthalenedisulfonic acid ion), alkyl sulfate ion (for example, methyl sulfate ion), sulfate ion, thiocyanate ion, perchlorate ion, tetrafluoroborate ion,
Picric acid ion, acetate ion, and trifluoromethanesulfonic acid ion. Further, another dye having a charge opposite to that of the ionic polymer or the dye may be used.

[0046] In the present invention a sulfo group SO ₃ ^- but is indicated as, when having a proton as a counter ion can be expressed as SO ₃ H.

M ₁ , m ₂ and m ₃ represent the numbers required to balance the charges, and are 0 when a salt is formed in the molecule. Preferably, the number is 0 or more and 4 or less.

In the general formula (II) of the present invention, Z ₁ , Z ₂ , Z
₃ , at least one of R ₁ , R ₂ , R ₃ , L ₁ to L ₉
And Z ₄ , Z ₅ , Z ₆ , R ₄ , R _{5 of} the general formula (III)
It is preferred that R ₆ , L ₁₀ to L ₁₅ are substituted with at least one thioether. The thioether group mentioned here can be any. Further, the case where an alkylthio group, an arylthio group, or a heterocyclylthio group is directly substituted on Z ₁ to Z ₆ and L ₁ to L ₁₅ is also included.

These thioether groups are represented by the following formula (X). Formula (X)

[0050]

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In the formula (X), A ₁ represents an alkylene group, alkenylene group, alkynylene group, arylene group or divalent heterocyclic group. k ₂ is 0 or 1. Q ₁ is synonymous with Q.

As A ₁ , for example, an alkylene group (eg, methylene, ethylene, propylene, butylene, pentylene), an arylene group (eg, phenylene, naphthylene), an alkenylene group (eg, ethenylene, propenylene), an alkynylene group (eg, Ethynylene, propionylene), heterocyclic divalent group (for example, 6-chloro-
1,3,5-triazine-2,4-diyl group, pyrimidine-2,4-diyl group, quinoxaline-2,3-diyl group). These groups may be further substituted, and examples of the substituent include the aforementioned V.

As Q or Q ₁ , the same substituents as those exemplified above for R ₂ and the like can be mentioned. Preferably, for example, an unsubstituted alkyl group of 1 to 18, preferably 1 to 7, particularly preferably 1 to 4, carbon atoms (eg methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl, octyl, dodecyl, octadecyl) ), A substituted alkyl group having 1 to 18, preferably 1 to 7, and particularly preferably 1 to 4 carbon atoms {for example, a heterocyclic group substituted by V mentioned as a substituent such as Z ₁ described above. Preferably, an aralkyl group (eg, benzyl, 2-phenylethyl), an unsaturated hydrocarbon group (eg, an allyl group), a hydroxyalkyl group (eg, 2-
Hydroxyethyl, 3-hydroxypropyl), carboxyalkyl group (eg, 2-carboxyethyl, 3-
Carboxypropyl, 4-carboxybutyl, carboxymethyl), alkoxyalkyl group (for example, 2-methoxyethyl, 2- (2-methoxyethoxy) ethyl),
Aryloxyalkyl group (for example, 2-phenoxyethyl, 2- (1-naphthoxy) ethyl), alkoxycarbonylalkyl group (for example, ethoxycarbonylmethyl,
2-benzyloxycarbonylethyl), an aryloxycarbonylalkyl group (for example, 3-phenoxycarbonylpropyl), an acyloxyalkyl group (for example, 2-acetyloxyethyl), an acylalkyl group (for example, 2-
Acetylethyl), carbamoylalkyl group (for example, 2
-Morpholinocarbonylethyl), a sulfamoylalkyl group (eg, N, N-dimethylcarbamoylmethyl), a sulfoalkyl group (eg, 2-sulfoethyl,
3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 2- [3-sulfopropoxy] ethyl, 2-hydroxy-3-sulfopropyl, 3-sulfopropoxyethoxyethyl), sulfoalkenyl group (for example, sulfopropenyl group) , A sulfatoalkyl group (for example, 2-
Sulfatoethyl group, 3-sulfatopropyl, 4-sulfatobutyl), heterocyclic-substituted alkyl group (for example, 2-
(Pyrrolidin-2-one-1-yl) ethyl, tetrahydrofurfuryl)}.

Further, an unsubstituted aryl group having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms, more preferably 6 to 8 carbon atoms (for example, phenyl group and 1-naphthyl group);
Having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms, more preferably an aryl group V is substituted cited as substituents, such as Z ₁ of the substituted aryl group (e.g., above 8 to 6 carbon atoms. Specific Specific examples include a p-methoxyphenyl group, a p-methylphenyl group, and a p-chlorophenyl group.), A C 1 to C 20, preferably a C 3 to C 10, and more preferably a C 4 to C 8 free radical. Substituted heterocyclic groups (eg, 2-furyl, 2-thienyl, 2
-Pyridyl group, 3-pyrazolyl, 3-isoxazolyl, 3-isothiazolyl, 2-imidazolyl, 2-oxazolyl, 2-thiazolyl, 2-pyridazyl, 2-pyridinyl, 3-pyrazyl, 2- (1,3,5-triazolyl ), 3- (1,2,4-triazolyl), 5-tetrazolyl), a substituted heterocyclic group having 1 to 20 carbon atoms, preferably 3 to 10 carbon atoms, and more preferably 4 to 8 carbon atoms (for example, as described above). V mentioned as the substituent, such as Z ₁ is and a heterocyclic group substituted. Specifically 5-methyl-2
-Thienyl group, 4-methoxy-2-pyridyl group and the like. ).

More preferred are the above-mentioned alkyl groups and aryl groups, and particularly preferred are unsubstituted alkyl groups (for example, methyl and ethyl groups) and unsubstituted aryl groups (for example, phenyl and naphthyl groups).

The substitution position of the thioether group represented by the formula (X) is preferably Z ₁ , Z ₂ , Z ₃ , R ₁ , R
₂ , R ₃ , Z ₄ , Z ₅ , Z ₆ , R ₄ , R ₅ , R ₆ , and more preferably Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ ,
Z ₆ , and particularly preferably Z ₁ , Z ₃ and Z ₄ .

K ₁ is preferably 1 or 2.

Most preferred as the heterocyclic ring represented by Z ₉ and SQ are as follows.

[0059]

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Among the methine dyes represented by the general formula (III), the methine dyes represented by the general formula (IV) are preferable.

[0061]

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In the formula (IV), Q ₂ has the same meaning as Q, and k ₃
It has the same meaning as that of k _1. R ₁₀ is R ₁ as defined, R ₁₁ has the same meaning as R ₂ as defined, R ₁₂ and R _3. L ₂₃ is L ₃ and synonymous, L
₂₄ has the same meaning as L _4, and L ₂₅ has the same meaning as L ₅ . M ₄ is M ₁
M ₄ is synonymous with m ₁ . V ₁ represents a monovalent substituent, and examples thereof include the same as those described above for V.

The general formulas (I) and (II) of the present invention are described below.
Specific examples of the compounds represented by (III) and (IV) are shown below, but the present invention is not limited thereto. (Dye with thioether group)

[0064]

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[0065]

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[0066]

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[0067]

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[0068]

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(Other dyes)

[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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The general formulas (I), (II) and (III) of the present invention
And compounds represented by (IV) are described in FM Harmer, "Heterocyclic Compounds-Cyanine Dyes and Relais Compounds".
ted Compounds), John Wiley & Sons, Inc.-New York, London, 1964, DMSturmer (DMStur)
mer), Heterocyclic Compounds-Special topics in h
eterocyclic chemistry, "Chapter 18, Section 14, pp. 482-515, John Wiley & Sons, Inc.-New York, London, 1977," Rods Chemistry of Carbon. "・ Compounds (Rodd's Chemistry of Carbon C)
ompounds) "2nd.Ed.vol.IV, partB, 1977, Chapter 15,
369-422, Elsevier Science Pub.
lishing Company Inc.), New York, and the like.

Synthesis of Synthesis Examples 1 and (3) Synthesis was performed according to the following scheme.

[0077]

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(A) 0.9 g (0.0018 mol),
(B) 0.5 ml of triethylamine was added to 0.8 g (0.0018 mol) and 20 ml of acetonitrile, and the mixture was heated and stirred on a water bath at 80 ° C. for 30 minutes. The reaction solution was cooled with water while stirring, and the crystals were separated by suction filtration. The obtained crystals were heated to reflux in 50 ml of methanol / 50 ml of chloroform, and after natural filtration, 50 ml of the solvent was distilled off. After standing, the precipitated crystals were separated by suction filtration and dried under reduced pressure.
(3) (blue powder, yield 0.87 g, yield 67%, λma
x = 661 nm, ε = 94300 (methanol), melting point 2
(More than 50 ℃)

The photothermographic material of the present invention has a light-sensitive layer containing a light-sensitive silver halide on at least one surface of a support, and the light-sensitive silver halide is represented by formula (I) or (I). It is spectrally sensitized by the sensitizing dye represented by II). Thereby, a photographic material having excellent photographic performance such as high sensitivity and low fog, no deterioration in photographic performance over time, and excellent image storability and silver tone can be obtained.

On the other hand, when other sensitizing dyes such as cyanine dyes different from the sensitizing dyes represented by the general formulas (I) and (II) are used, fog increases and sensitivity decreases. And the photographic performance is inferior. In addition, the photographic performance deteriorates with time, and the image storability deteriorates.
On the other hand, when the water-resistant protective layer is not provided, photographic performance is remarkably deteriorated, such as fog increase and sensitivity decrease. In addition, the photographic performance deteriorates with time, such as a marked decrease in sensitivity with time, and further, image storability deteriorates and silver tone deteriorates.

The effects of the present invention can be further improved by adding sensitizing dyes represented by formulas (I) and (II) during the preparation of the photosensitive silver halide.

The main binder such as the photosensitive layer of the photothermographic material of the present invention is preferably a polymer latex described below. However, the "polymer latex" referred to here is a water-insoluble hydrophobic polymer dispersed as fine particles in a water-soluble dispersion medium. The dispersion state is such that the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or partially dispersed in polymer molecules and molecular chains themselves are molecularly dispersed. Any of them may be used.

The polymer latex of the present invention is described in "Synthetic Resin Emulsion" (edited by Tadashi Okuda and Hiroshi Inagaki, published by Polymer Publishing Association (1978)), and "Application of Synthetic Latex" (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Kasahara) Edited by Keiji, published by the Society of Polymer Publishing (1993)), and "Synthesis of Synthetic Latex (Souichi Muroi, published by the Society of Polymer Publishing (1970))".

The average particle size of the dispersed particles is preferably in the range of 1 to 50,000 nm, more preferably in the range of about 5 to 1000 nm. There is no particular limitation on the particle size distribution of the dispersed particles, and they may have a wide particle size distribution or a monodispersed particle size distribution.

As the polymer latex of the present invention, other than the usual polymer latex having a uniform structure, a so-called core / polymer latex may be used.
Shell type latex may be used. In this case, it may be preferable to change the glass transition temperature of the core and the shell.

The minimum film forming temperature (MFT) of the polymer latex of the present invention is preferably from -30 ° C to 90 ° C, more preferably from about 0 ° C to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. A film-forming aid is also called a plasticizer, and is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of a polymer latex.For example, see `` Synthesis of Synthetic Latex (Souichi Muroi, published by Polymer Publishing Association, 1970). ) "It is described in.

The polymer used in the polymer latex of the present invention includes acrylic resins, vinyl acetate resins, polyester resins, polyurethane resins, rubber resins, vinyl chloride resins, vinylidene chloride resins, polyolefin resins, and copolymers thereof. There is.

The polymer may be a linear polymer, a branched polymer, or a crosslinked polymer. The polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized.

In the case of a copolymer, it may be a random copolymer or a block copolymer. The molecular weight of the polymer is from 5000 to 100000, preferably from 10,000 to 1000 in number average molecular weight.
About 00 is preferable. If the molecular weight is too small, the mechanical strength of the image forming layer such as the photosensitive layer is insufficient, and if it is too large, the film-forming property is poor, which is not preferable.

The polymer of the polymer latex used in the present invention preferably has an equilibrium water content at 25 ° C. and 60% RH of 2% by weight or less, more preferably 1% by weight or less. The lower limit of the equilibrium water content is not particularly limited, but is preferably 0.01 wt%, more preferably 0.03 wt%. For the definition and measurement method of the equilibrium moisture content, see, for example,
4, Polymer Material Testing Method (Polymer Society of Japan, Jinjinshokan) ”and so on.

Specific examples of the polymer latex used as the binder of the present invention are as follows. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2 ethylhexyl acrylate / styrene / acrylic acid copolymer, styrene / butadiene /
Latex of acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer, latex of methyl methacrylate / vinyl chloride / acrylic acid copolymer, latex of vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer and the like.

[0092] Such polymers are also commercially available, and the following polymers can be used.

For example, as an example of an acrylic resin, Sebian
A-4635,46583,4601 (These are Daicel Chemical Industries, Ltd.)
, Nipol Lx811, 814, 821, 820, 857 (all manufactured by Nippon Zeon Co., Ltd.)
HYDRAN AP10, 2 as polyurethane resin such as TEX ES650, 611, 675, 850 (all manufactured by Dainippon Ink and Chemicals, Inc.), WD-size, WMS (all manufactured by Eastman Chemical)
Rubber-based resins such as 0, 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.) include LACSTAR 7310K, 3307B, 4700H, 71
32C (Dai Nippon Ink Chemical Co., Ltd.), Nipol Lx416,
410, 438C, 2507, (all made by Nippon Zeon Co., Ltd.)
Vinyl chloride resins such as G351 and G576 (both manufactured by Zeon Corporation), and vinylidene chloride resins such as L502 and L5
13 (above Asahi Kasei Kogyo Co., Ltd.) and other olefin resins such as Chemipearl S120 and SA100 (above Mitsui Petrochemical Co., Ltd.)
Manufactured).

These polymers may be used alone, or may be used by blending two or more kinds as necessary.

The main binder in the photosensitive layer of the present invention means that 50% by weight or more, more preferably 70% by weight or more of the total binder in the photosensitive layer is the polymer of the present invention.

As these binders, the polymer of the present invention may be used alone, or two or more of them may be blended if necessary. If necessary, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, or hydroxypropylcellulose may be added to the photosensitive layer (emulsion layer) of the light-sensitive material of the present invention. The addition amount of these hydrophilic polymers is preferably 30% by weight or less, more preferably 20% by weight or less of the total binder in the photosensitive layer.

The amount of the binder in the photosensitive layer of the present invention is such that the weight ratio of (total binder) / (silver halide) is 400 to 5,
More preferably, the range is 200 to 10.

The solvent for the coating solution for the emulsion layer of the light-sensitive material of the present invention (for the sake of simplicity, the solvent and the dispersion medium are collectively referred to as a solvent) is preferably an aqueous solvent containing 30% by weight or more of water. As a component other than water, any water-miscible organic solvent such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate may be used. The water content of the solvent of the coating solution is preferably at least 50% by weight, more preferably at least 70% by weight. Preferred examples of the solvent composition include water / methyl alcohol = 90/10, water / methyl alcohol = 70/30, water / methyl alcohol / dimethylformamide = 80/15/5, and water / methyl alcohol / ethyl cellosolve = 85. / 10/5, water / methyl alcohol / isopropyl alcohol = 85/10/5.

In the present invention, a non-sensitive organic silver salt is used.

The organic silver salt that can be used in the present invention includes:
Relatively stable to light, but forms a silver image when heated to 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of photosensitive silver halide) and a reducing agent It is a silver salt. The organic silver salt can be any organic substance including a source capable of reducing silver ions. Silver salts of organic acids, 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 whose ligands have a complex stability constant in the range of 4.0 to 10.0 are also preferred. The silver donor material is preferably from about 5 to about 5% of the imaging layer.
70% by weight. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate, silver fumarate, and tartaric acid. Silver, silver linoleate, silver butyrate and silver camphorate, and mixtures thereof.

Silver salts of compounds containing a mercapto group or a thione group and derivatives thereof can also be used.
Preferred examples of these compounds include 3-mercapto-4
-Silver salt of phenyl-1,2,4-triazole, silver salt of 2-mercaptobenzimidazole, silver salt of 2-mercapto-5-aminothiadiazole, silver salt of 2- (ethylglycolamide) benzothiazole, S- Alkylthioglycolic acid (
(The alkyl group has 12 to 22 carbon atoms.) A silver salt of thioglycolic acid such as a silver salt, a silver salt of dithiocarboxylic acid such as a silver salt of dithioacetic acid, a silver salt of thioamide, 5-carboxyl-1 -Silver salt of methyl-2-phenyl-4-thiopyridine,
Silver salt of mercaptotriazine, silver salt of 2-mercaptobenzoxazole, silver salt described in U.S. Pat.No.4,123,274,
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,
Silver salts of thione compounds such as the silver salt of 3- (3-carboxyethyl) -4-methyl-4-thiazoline-2-thione described in U.S. Pat. No. 3,301,678. Furthermore, compounds containing an imino group can also be used. Preferred examples of these compounds include silver salts of benzotriazole and derivatives thereof, for example, silver salts of benzotriazole such as silver methylbenzotriazole, silver salts of halogen-substituted benzotriazole such as silver 5-chlorobenzotriazole, and US Pat. 4,220,709, such as silver salts of 1,2,4-triazole or 1-H-tetrazole, and silver salts of imidazole and imidazole derivatives. 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. In the present invention, the minor axis is 0.01 μm or more.
20 μm or less, major axis 0.10 μm or more and 5.0 μm or less, minor axis 0.01 μm or more and 0.15 μm or less, major axis 0.10 μm or more
It is more preferably 4.0 μm or less. The particle size distribution of the organic silver salt is preferably monodispersed. Monodisperse and the minor axis, the percentage of the value obtained by dividing the standard deviation of the length of each major axis by each minor axis, major axis is preferably 100% or less, more preferably
It is at most 80%, more preferably at most 50%. The shape of the organic silver salt can be measured from a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring the monodispersity, there is a method of determining the standard deviation of the volume-weighted average diameter of the organic silver salt, the percentage of the value divided by the volume-weighted average diameter (coefficient of variation) is preferably 100% or less, more It is preferably at most 80%, more preferably at most 50%. As a measurement method, for example, the particle size (volume weighted average diameter) obtained by irradiating a laser beam to an organic silver salt dispersed in a liquid and obtaining an autocorrelation function with respect to the time change of fluctuation of the scattered light is obtained. Can be.

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

The organic silver salt which can be used in the present invention is a method of preparing a solid fine particle dispersion using a dispersant for the purpose of obtaining fine particles having a small particle size and no aggregation. The method of dispersing the organic silver salt into solid fine particles is carried out by using a known fine means (for example, a ball mill, a vibrating ball mill, a planetary ball mill, a sand mill, a colloid mill, a jet mill, a roller mill) in the presence of a dispersing agent. Can be dispersed.

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

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

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

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

[0109] While the organic silver salt according to the invention can be used in a desired amount, preferably from 0.1 to 5 g / m ² indicates the coating amount per photographic material 1 m ^2, more preferably from 1 ~3g / m ^2.

The method of forming the photosensitive silver halide in the present invention is well known in the art, and uses, for example, the methods described in Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458. be able to. The grain size of the photosensitive silver halide is preferably small for the purpose of suppressing the white turbidity after image formation, specifically 0.20 μm or less, more preferably 0.01 μm or less.
0.15 μm or less, more preferably 0.02 μm or more and 0.12 μm
m or less is good. 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 it is preferable that the proportion of the surface having high spectral sensitization efficiency when the spectral sensitizing dye used is adsorbed is high. . The ratio is preferably at least 50%, more preferably at least 65%, even more preferably at least 80%. The ratio of the Miller index is determined by the method described in T. Tani; J. Imaging Sci., 29, 165 (1985), which utilizes the adsorption dependence of the sensitizing dye on the {111} and {100} planes. You can ask. There is no particular limitation on the halogen composition of the photosensitive silver halide, and silver chloride,
Silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide, silver iodide may be used, but in the present invention, silver bromide or silver iodobromide is preferably used. it can. Particularly preferred is silver iodobromide, and the silver iodide content is preferably from 0.1 mol% to 40 mol%, more preferably 0.1 mol%.
It is more preferably at least 20 mol%. 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 preferred example, the silver iodide content of the grain surface High silver iodobromide grains can be used. Preferably, silver halide grains having a core / shell structure can be used. As the structure, core / shell particles having preferably a 2- to 5-layer structure, more preferably a 2- to 4-layer structure, can be used.

The photosensitive silver halide grains of the present invention preferably contain at least one complex of a metal selected from rhodium, rhenium, ruthenium, osnium, iridium, cobalt, mercury or iron. One type of these metal complexes may be used, or two or more types of complexes of the same metal and different metals may be used in combination. The preferable content is in the range of 1 nmol to 10 mmol, and more preferably in the range of 10 nmol to 100 μmol per 1 mol of silver. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used. As the 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 content of the metal complex in the silver halide may be uniform, may be contained at a high concentration in the core portion, or may be contained at a high concentration in the shell portion, and there is no particular limitation.

The photosensitive silver halide grains can be desalted by washing with water by 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, diacyl tellurides, 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
And the compounds described in British Patent No. 618,061 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. Reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ion during grain formation.

The amount of the photosensitive silver halide used in the present invention is preferably 0.01 mol to 0.5 mol, more preferably 0.02 mol to 0.3 mol, and more preferably 0.03 mol to 1 mol of the organic silver salt. It is particularly preferably at least 0.25 mol and not more than 0.25 mol.

In the present invention, the photosensitive silver halide is preferably added at the time of preparing a coating solution. The step of preparing a coating solution as referred to herein indicates a step of mixing separately prepared photosensitive silver halide, an organic silver salt and other materials necessary for photographic properties and coatability. The mixing conditions are not particularly limited as long as the effects of the present invention are sufficiently exhibited, except that separately added photosensitive silver halide grains and organic silver salts which have been individually prepared at the time of preparing the coating solution, are preferably used. Better results can be obtained by adding silver halide after mixing the organic acid silver and the binder used in the present invention. In addition,
The organic silver salt is usually added to the same layer as the photosensitive silver halide as described above, and such an addition method is preferable.
In some cases, it may be added to another layer.

The sensitizing dyes used in the present invention may be used alone or in combination of two or more. 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 described in Research Disclosure Vol. 176, Volume 17643 (December, 1978), page 23, IV, J, or JP-B-49-25500. No. 43
-4933, JP-A-59-19032 and JP-A-59-192242.

The sensitizing dyes used in the present invention may be used in combination of two or more. The sensitizing dyes can be added to the silver halide emulsion by dispersing them directly in the emulsion or by adding water, methanol, ethanol, propanol, acetone, methyl cellosolve, 2,2,3,3- Solvent such as tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, N-dimethylformamide alone or It may be dissolved in a mixed solvent and added to the emulsion.

Further, as disclosed in US Pat. No. 3,469,987, a dye is dissolved in a volatile organic solvent, and this solution is dispersed in water or a hydrophilic colloid. Method of adding to Japanese Patent Publication No. 44-23389,
As disclosed in JP-A-44-27555 and JP-A-57-22091, a dye is dissolved in an acid and this solution is added to the emulsion, or an acid or base is added to the emulsion as an aqueous solution in the presence of an acid or base. A method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to a emulsion as disclosed in U.S. Pat. Nos. 3,822,135 and 4,006,025, JP-A-51-7, a method of directly dispersing a dye in a hydrophilic colloid and adding the dispersion to an emulsion as disclosed in
As disclosed in Japanese Patent No. 4624, a method in which a dye is dissolved using a compound that causes red shift, and this solution is added to an emulsion can also be used. Also, ultrasonic waves can be used for dissolution.

The sensitizing dye to be used in the present invention may be added to the silver halide emulsion of the present invention at any stage of the emulsion preparation which has been found to be useful. For example, U.S. Pat.Nos. 2,735,766 and 3,628,960
No. 4,183,756, No. 4,225,666, JP-A-58-18414
As disclosed in the specifications of JP-A Nos. 2 and 60-196749, chemical ripening is carried out during the silver halide grain forming step and / or before the desalting step, during the desilvering step and / or after the desalting step. Before the start of the process, as disclosed in the specification of JP-A-58-113920, etc., immediately before or during the process of chemical ripening, or after the chemical ripening and before the application of the emulsion before coating. If so, it may be added at any time in the process. Further, as disclosed in the specification of U.S. Pat. No. 4,225,666, Japanese Patent Application Laid-Open No. 58-7629, etc., the same compound may be used alone or in combination with a compound having a heterogeneous structure, for example, during the particle forming step. The compound may be divided and added during the ripening step or after the completion of the chemical ripening, or may be added separately before or during the chemical ripening or after the completion of the chemical ripening. May be added.

The sensitizing dye represented by formula (I) or (II) may be added at any time described above, but preferably after the silver halide grains have been formed, the coating solution of an aqueous solvent is added to the aqueous solution. It is preferable to add silver before adding silver. The amount of the sensitizing dye used in the present invention may be a desired amount in accordance with the performance such as sensitivity and fog, but is preferably 10 ^-6 to 1 mol per mol of silver halide in the photosensitive layer, and more preferably 10 ^-4. More preferably, it is 10 to 10 ^-1 mol.

In the present invention, it is preferable to contain a compound represented by the following general formula (X).

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In the formula, R represents an aliphatic hydrocarbon group, an aryl group or a heterocyclic group. M represents a hydrogen atom or a cation.

N is a number determined to make the molecule neutral. It is preferable that the compound represented by the general formula (X) is added to the photosensitive silver halide in advance, and then the photosensitive silver halide is added when preparing a coating solution.

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

R represents an aliphatic hydrocarbon group, an aryl group or a heterocyclic group.

The aliphatic hydrocarbon group represented by R is a straight-chain,
A branched or cyclic alkyl group (preferably having 1 to 3 carbon atoms)
0, more preferably 1 to 22 carbon atoms, still more preferably 1 to 20 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, n-octyl, n-decyl, n-hexadecyl, octadecyl, Propyl, cyclopentyl, cyclohexyl and the like. ), An alkenyl group (preferably having 2 to 30 carbon atoms, more preferably 2 carbon atoms)
-20, more preferably 2-16 carbon atoms, such as vinyl, allyl, 2-butenyl, 3-pentenyl and the like. ), Alkynyl group (preferably having 2 to 30 carbon atoms, more preferably having 2 to 20 carbon atoms, still more preferably having 2 to 2 carbon atoms)
16, for example, propargyl, 3-pentynyl and the like. ), And may have a substituent. The aliphatic hydrocarbon group represented by R 1 is preferably an alkyl group.

The aryl group represented by R may be monocyclic or condensed, preferably has 6 to 30 carbon atoms, more preferably has 6 to 20 carbon atoms, and still more preferably has 6 to 16 carbon atoms. It is a cyclic or bicyclic aryl group (eg, phenyl, naphthyl, etc.) and may have a substituent. The aryl group represented by R 2 is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group.

The heterocyclic group represented by R is N, O or
3 to 10-membered saturated or unsaturated heterocyclic ring containing at least one atom of S 1, which may be a single ring or may form a condensed ring with another ring.

As the heterocyclic group, preferably 5 to 6
Membered unsaturated heterocyclic group, more preferably 5 to
It is a 6-membered aromatic heterocyclic group. More preferably, it is a 5- or 6-membered aromatic heterocyclic group containing a nitrogen atom, particularly preferably a 5- or 6-membered aromatic heterocyclic group containing 1 to 4 nitrogen atoms, which may have a condensed ring. Preferably, it may have a substituent.

Specific examples of heterocycles include, for example, 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, benzothiazole, Benzselenazole, indolenine, tetraazaindene, perimidine and the like can be mentioned. Preferably as a heterocycle, 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, and more preferably. Is pyridine, pyrimidine, pyrazine, pyridazine, triazole, triazine, thiadiazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, tetrazole, benzimidazole, benzoxazole, benzothiazole,
Tetraazaindene, more preferably triazole, thiazole, thiadiazole, oxazole, oxadiazole, tetrazole, benzimidazole,
Benzoxazole, benzothiazole, and particularly preferably benzimidazole, benzoxazole,
Benzthiazole, most preferably benzimidazole.

Examples of the substituent for the aliphatic hydrocarbon group, aryl group or heterocyclic group represented by R include, for example, an alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms,
Particularly preferred are those having 1 to 8 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, hexyl, n-heptyl, n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl and the like. No. ), An alkenyl group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 12 carbon atoms, particularly preferably having 2 to 8 carbon atoms, and examples thereof include vinyl, allyl, 2-butenyl, and 3-pentenyl. ), Alkynyl group (preferably 2-20 carbon atoms, more preferably 2 carbon atoms
-12, particularly preferably 2-8 carbon atoms, such as propargyl and 3-pentynyl. ), An aryl group (preferably having 6 to 30 carbon atoms, more preferably having
It has from 6 to 20, particularly preferably from 6 to 12, carbon atoms and includes, for example, phenyl, p-methylphenyl, naphthyl and the like. ), An amino group (preferably having 0 to 20 carbon atoms, more preferably having 0 to 10 carbon atoms, particularly preferably having 0 to 6 carbon atoms, and examples thereof include amino, methylamino, dimethylamino, diethylamino, and dibenzylamino. Is done.)
An alkoxy group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 12 carbon atoms, particularly preferably having 1 to 8 carbon atoms, such as methoxy, ethoxy, and butoxy), and an aryloxy group (preferably Is 6 to 2 carbon atoms
It has 0, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include phenyloxy and 2-naphthyloxy. ), An acyl group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms, for example, acetyl, benzoyl,
Formyl, pivaloyl and the like can be mentioned. ), An alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 16 carbon atoms, particularly preferably having 2 to 12 carbon atoms, for example, methoxycarbonyl, ethoxycarbonyl and the like), and aryloxycarbonyl Group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms,
Particularly preferably, it has 7 to 10 carbon atoms, such as phenyloxycarbonyl. ), Acyloxy group
(Preferably has 2 to 20 carbon atoms, more preferably 2 to 2 carbon atoms.
16, particularly preferably 2 to 10 carbon atoms, such as acetoxy and benzoyloxy. ), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 16 carbon atoms, particularly preferably having 2 to 10 carbon atoms, such as acetylamino, hexanoylamino, octanoylamino, benzoylamino and the like. ), An alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably having 2 to 16 carbon atoms, and particularly preferably having 2 to 2 carbon atoms.
12, for example, methoxycarbonylamino and the like. ), An aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably having 7 to 12 carbon atoms, such as phenyloxycarbonylamino, etc.), and sulfonylamino Group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms, for example, methanesulfonylamino, benzenesulfonylamino, etc.), a sulfamoyl group (preferably carbon It has a number of 0 to 20, more preferably 0 to 16, and particularly preferably 0 to 12, and includes, for example, sulfamoyl, methylsulfamoyl, dimethylsulfamoyl, phenylsulfamoyl and the like.), Carbamoyl Base
(Preferably having 1 to 20 carbon atoms, more preferably 1 to 20 carbon atoms.
16, particularly preferably having 1 to 12 carbon atoms, such as carbamoyl, methylcarbamoyl, diethylcarbamoyl,
Heptylcarbamoyl, phenylcarbamoyl and the like can be mentioned. ), An alkylthio group (preferably having 1 to
20, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as methylthio and ethylthio. ), An arylthio group (preferably having 6 carbon atoms)
-20, more preferably 6-16 carbon atoms, particularly preferably 6-12 carbon atoms, such as phenylthio. ), A sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, and particularly preferably having 1 to 12 carbon atoms.
And for example, mesyl, tosyl and the like. ),
A sulfinyl group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms, such as methanesulfinyl and benzenesulfinyl), and a ureido group (preferably having number
It has 1 to 20, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms, and examples thereof include ureido, methylureide, and phenylureide. ), A phosphoric amide group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms, and examples thereof include diethylphosphoramide and phenylphosphoramide. ), Hydroxy group, mercapto group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group (including sulfonato group),
Carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, heterocyclic group (for example, imidazolyl, pyridyl, furyl, thienyl, piperidyl, morpholino, thiazolyl and the like). These substituents may be further substituted. When there are two or more substituents, they may be the same or different.
Also, two or more substituents may be bonded to each other to form a 5- to 7-membered carbon ring (cyclopentane, cyclohexane, benzene, cycloheptatriene, etc.).

The substituent is preferably an alkyl group, an aryl group, an amino 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, or an alkoxy group. Carbonylamino group, aryloxycarbonylamino group, sulfonylamino group, sulfamoyl group, carbamoyl group, ureido group, hydroxy group, mercapto group, halogen atom, sulfo group (including sulfonato group), carboxyl group, nitro group, cyano group, A heterocyclic group, more preferably an alkyl group, an aryl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamido. Group, sulfonylamino group, sulfamoyl group, carbamoyl group, ureido group, halogen atom, heterocyclic group, more preferably an alkyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, An aryloxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group, a ureido group, a halogen atom, and a heterocyclic group are preferable, and an alkyl group is particularly preferable.

R is preferably a heterocyclic ring, more preferably a 5- or 6-membered unsaturated heterocyclic group which may have a condensed ring, and further preferably a condensed ring. And a 6-membered aromatic heterocyclic group. Particularly preferably, a nitrogen atom which may have a condensed ring is
5- or 6-membered aromatic heterocyclic group containing 1 to 4 atoms.

M represents a hydrogen atom or a cation.

The cation represented by M represents an organic or inorganic cation, for example, an alkali metal ion (Li ⁺ , Na
⁺ , K ⁺ , Cs ^+, etc.), alkaline earth metal ions (Mg
²⁺ , Ca ²⁺ ), ammonium (ammonium, trimethylammonium, triethylammonium, tetramethylammonium, tetraethylammonium, tetrabutylammonium, 1,2-ethanediammonium, etc.), pyridinium, imidazolium, phosphonium (
Tetrabutylphosphonium, etc.). M
Are preferably a hydrogen atom and an alkali metal ion, and more preferably a hydrogen atom.

N represents a number determined so that the molecule becomes neutral. For example, if R is a monovalent cation, n is 0. When R is neutral and M is a monovalent cation, n is
It becomes 1.

The compound represented by formula (X) may be a conjugate isomer thereof.

Among the compounds represented by the general formula (X), a compound represented by the following general formula (Xa) is preferred.

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In formula (Xa), M has the same meaning as in formula (X), and the preferred range is also the same. Q ₁₀ represents an atom group necessary for forming a nitrogen-containing aromatic hetero ring. Examples of the nitrogen-containing aromatic hetero ring formed by Q _10, such as pyrrole, imidazole, pyrazole,
Pyridine, pyrimidine, pyrazine, pyridazine, triazole, triazine, indole, indazole, purine, thiazole, thiadiazole, oxazole, oxadiazole, quinoline, phthalazine, naphthyridine,
Quinoxaline, quinazoline, cinnoline, pteridine,
Examples include acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzthiazole, benzselenazole, tetraazaindene, perimidine, and the like, and a ring condensed thereto may be used. Preferably imidazole,
Pyrazole, pyridine, pyrimidine, pyrazine, pyridazine, triazole, triazine, indole, indazole, purine, thiazole, thiadiazole, oxazole, oxadiazole, quinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline,
Pteridine, acridine, tetrazole, benzimidazole, benzoxazole, benzothiazole, benzselenazole, tetraazaindene and the like,
More preferably imidazole, triazole, thiazole, thiadiazole, oxazole, oxadiazole, tetrazole, benzimidazole, benzoxazole, benzothiazole, even more preferably benzimidazole, benzoxazole, benzothiazole, particularly preferably benzimidazole. is there.
The nitrogen-containing aromatic hetero ring formed by Q may have a substituent, and examples of the substituent include, for example, those represented by the general formula (X)
The substituents mentioned for R 1 can be applied.

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

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[0151]

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[0154]

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[0155]

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[0156]

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[0159]

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The compounds of the formula (X) of the present invention may be used alone or in combination of two or more.

The amount of the compound of the formula (X) used in the present invention is not particularly limited, but is preferably 10 ^-8 to 10 ^-1 mol per mol of the total of silver halide and organic acid silver. Is particularly preferred, and particularly preferably in the range of 10 ^-6 to 10 ^-1 mol. If the added amount is too small, the effect of the present invention cannot be obtained, and if the added amount is too large, the storage stability with time and fog during thermal development may be deteriorated.

The time of addition of the compound of the general formula (X) used in the present invention has been recognized to be useful.
During any step. For example, the stage before the silver halide grain forming step and / or desalting, the period during the desalting step and / or after the desalting and before the start of chemical ripening, the period immediately before or during the chemical ripening, the chemical ripening rear,
The emulsion may be added at any stage in the process before the emulsion is coated before coating. Further, silver halide may be added to a coating solution to which the compound of the general formula (X) is added in advance.

The same compound may be used alone or in combination with a compound having a different structure, for example, during the particle formation step, during the chemical ripening step or after the completion of the chemical ripening, or before the chemical ripening or during the step and after the completion. The compound may be added in portions such as by dividing, or the compound to be added in portions and the combination of the compounds may be changed and added.

The compound of the formula (X) used in the present invention may be added at any time as described above, but it is preferable to add the compound to the silver halide before adding the silver halide to the coating solution. .

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 preferably contained in an amount of 5 to 50% (mole), more preferably 10 to 40% (mole), based on 1 mol of silver on the surface having the image forming layer. The layer to which the reducing agent is added may be any layer on the side having the image forming layer. When it is added to a layer other than the image forming layer, it is preferable to use a relatively large amount of 10 to 50% (mol) with respect to 1 mol of silver. Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material utilizing an organic silver salt, a wide range of reducing agents are disclosed in JP-A-46-6074 and JP-A-47-1238.
No. 47-33621, No. 49-46427, No. 49-115540, No.
50-14334, 50-36110, 50-147711, 51-326
No. 32, No. 51-1023721, No. 51-32324, No. 51-51933,
52-84727, 55-108654, 56-146133, 57
-82828, 57-82829, JP-A-6-3793, U.S. Pat.
667,9586, 3,679,426, 3,751,252, 3,75
No. 1,255, No. 3,761,270, No. 3,782,949, No. 3,839,
048, 3,928,686, 5,464,738, German patent 2,
No. 321,328 and EP 692,732. For example, amide oximes such as phenylamide oxime, 2-thienyl amide oxime and p-phenoxy phenyl amide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; 2,2-bis
A combination of an aliphatic carboxylic acid aryl hydrazide and ascorbic acid, such as a combination of (hydroxymethyl) propionyl-β-phenylhydrazine and ascorbic acid; polyhydroxybenzene, hydroxylamine,
Combinations of reductone and / or hydrazine (eg, a combination of hydroquinone and bis (ethoxyethyl) hydroxylamine, piperidinohexose reductone or formyl-4-methylphenylhydrazine); phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid And hydroxamic acids such as β-alinine hydroxamic acid; combinations of azines with sulfonamidophenols (eg, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol); ethyl-α-cyano-2-methylphenyl Α-cyanophenylacetic acid derivatives such as acetate and ethyl-α-cyanophenylacetate; 2,2-dihydroxy-1,1-binaphthyl, 6,6-dibromo
Bis as exemplified for -2,2-dihydroxy-1,1-binaphthyl and bis (2-hydroxy-1-naphthyl) methane
-β-naphthol; a combination of bis-β-naphthol and a 1,3-dihydroxybenzene derivative (eg, 2,4-dihydroxybenzophenone or 2,4-dihydroxyacetophenone); 3-methyl-1-phenyl-5-pyrazolone 5-pyrazolones; reductones as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone; 2,6-dichloro-4-
Sulfonamidophenol reducing agents such as benzenesulfonamidophenol and p-benzenesulfonamidophenol; 2-phenylindane-1,3-dione; 2,2
-Chromans such as dimethyl-7-t-butyl-6-hydroxychroman; 2,6-dimethoxy-3,5-dicarbethoxy-1,4
-1,4-dihydropyridines such as dihydropyridine; bisphenols (for example, bis (2-hydroxy-3-t-butyl-
5-methylphenyl) methane, 2,2-bis (4-hydroxy-
3-methylphenyl) propane, 4,4-ethylidene-bis
(2-t-butyl-6-methylphenol), 1,1, -bis (2-
Hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, etc.); ascorbic acid derivatives (for example, palmitic acid 1- And aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indan-1,3-diones; chromanol (such as tocopherol). Particularly preferred reducing agents are bisphenol and chromanol.

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

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

In a photothermographic material using an organic silver salt, a wide range of color toning agents are disclosed in JP-A-46-6077 and JP-A-47-10282.
Nos. 49-5019, 49-5020, 49-91215, 49
-91215, 50-5024, 50-32927, 50-67132
No. 50-67641, No. 50-114217, No. 51-3223, No. 5
1-27923, 52-14788, 52-99813, 53-1020
No. 53-76020, No. 54-156524, No. 54-156525,
No. 61-183642, JP-A-4-56848, JP-B-49-10727
No. 54-20333, U.S. Pat.Nos. 3,080,254, 3,446,64
No. 8, 3,782,941, 4,123,282, 4,510,236
And British Patent 1380795 and Belgian Patent 841910. Examples of toning agents are phthalimide and N-
Hydroxyphthalimide; succinimide, pyrazoline
And cyclic imides such as quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinedione; naphthalimides (eg, N-hydroxy-1 , 8-naphthalimide); cobalt complex (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-
Dicarboximides); and blocked pyrazoles, isothiuronium derivatives and certain photobleaching agents (
For example, 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 derivative or metal salt, or 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 (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); phthalazine, a phthalazine derivative or a metal salt, or 4- (1-naphthyl) ) Derivatives such as phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (for example, phthalic acid,
Quinazolinedione, such as 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride);
Benzoxazine or naphthoxazine derivatives; rhodium complexes that function not only as color tone regulators but also in-situ as sources of halide ions for silver halide formation, such as ammonium hexachlororhodate (III), rhodium bromide, rhodium nitrate And potassium hexachlororhodate (III); 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-dione such as 1,3-benzoxazine-2,4-dione; pyrimidine and asymmetric triazine (for example, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine and the like), Azauracil and tetraazapentalene derivatives (for example, 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).

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

The silver halide emulsion according to the invention or /
And the organic silver salts can be further protected against the formation of additional fog by antifoggants, stabilizers and stabilizer precursors, and can be stabilized against reduced sensitivity during storage in inventory. Suitable antifoggants, stabilizers and stabilizer precursors which can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716, and U.S. Pat.Nos. 2,886,437 and 2,44.
No. 4,605, azaindene, U.S. Pat.No. 2,728,663 mercury salt, U.S. Pat.No. 3,287,135 urazole, U.S. Pat.No. 3,235,652 sulfocatechol, U.K. patent 623,448 oxime, nitrone,
Nitroindazole, polyvalent metal salt described in U.S. Pat.No. 2,839,405, thyuronium salt described in U.S. Pat.No. 3,220,839, and U.S. Pat.Nos. 2,566,263 and 2,597,9
No. 15 palladium, platinum and gold salts, U.S. Patent
Halogen-substituted organic compounds described in 4,108,665 and 4,442,202; U.S. Pat.Nos. 4,128,557 and 4,137,07
Nos. 9,138,365 and 4,459,350 and the phosphorus compounds described in U.S. Pat. No. 4,411,985.

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

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

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

The photothermographic material of the present invention may contain benzoic acids for the purpose of increasing the sensitivity and preventing fog. The benzoic acids of the present invention may be any benzoic acid derivative, but examples of preferred structures include those described in U.S. Pat.
No. 9, No. 4, 152, 160, Japanese Patent Application No. 8-151242, No. 8-151241
And the compounds described in JP-A-8-98051. The benzoic acids of the present invention may be added to any part of the light-sensitive material. However, the added layer is preferably added to the layer having the photosensitive layer, and more preferably added to the organic silver salt-containing layer. . The benzoic acid of the present invention may be added at any time during the preparation of the coating solution, and when it is added to the organic silver salt-containing layer, it may be added at any time from the preparation of the organic silver salt to the preparation of the coating solution. It is preferable after salt preparation and immediately before application. The benzoic acid of the present invention may be added by 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 benzoic acid of the present invention may be added in any amount, but preferably 1 μmol or more and 2 mol or less, more preferably 1 mmol or more per 1 mol of silver.
0.5 mol or less is more preferred.

In the present invention, a disulfide compound or a thione compound can be contained in order to suppress or accelerate development to control development, to improve spectral sensitization efficiency, to improve storage stability before and after development, and the like. .

In the photosensitive layer according to the invention, a polyhydric alcohol (for example, US Pat.
Glycerin and diols of the type described in U.S. Pat. No. 0,404), 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.

In the present invention, a hydrazine derivative may be used. 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, compounds 1 to 38 described on pages 8 to 18 of the same publication. General formula (4) described in JP-A-6-230497, general formula
(5) and compounds represented by the 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. A compound represented by the general formula (1) and the general formula (2) described in JP-A-6-289520,
Specifically, compounds 1-1) to 1-1 described on pages 5 to 7 of the same publication
7) and 2-1). Compounds represented by (Chemical Formula 2) and (Chemical Formula 3) described in JP-A-6-313936, specifically, compounds described on pages 6 to 19 of the same. JP-A-6-313951 describes
The compounds represented by 1), specifically, the compounds described on pages 3 to 5 of the same publication. Compounds represented by the general formula (I) described in JP-A-7-5610, specifically, compounds I-1 to I-38 described on pages 5 to 10 of the same publication. The general formula (I) described in JP-A-7-77783
Compounds represented by I), specifically, compounds II-1 to II-102 described on pages 10 to 27 of the publication. Compounds represented by formulas (H) and (Ha) described in JP-A-7-104426, specifically, compounds H-1 to H-44 described on pages 8 to 15 of the same publication. 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. Hei 7-191007, particularly the general formula (A) , General formula (B), General formula (C), General formula
(D), compounds represented by formulas (E) and (F), specifically, compounds N-1 to N-30 described in the same specification. Japanese Patent Application 7-1
Compounds represented by general formula (1) described in No. 91007, specifically, compounds D-1 to D-55 described in the same specification.

When a hydrazine nucleating agent is used in the present invention, a suitable water-miscible organic solvent such as an alcohol (
Methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone)
, Dimethylformamide, dimethylsulfoxide, methylcellosolve and the like.

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

When a hydrazine-based nucleating agent is used in the present invention, the hydrazine-based nucleating agent may be added to any layer of the silver halide emulsion layer (photosensitive layer) on the side of the silver halide emulsion layer with respect to the support or another hydrophilic colloid layer. However, it is preferably added to the silver halide emulsion layer or the hydrophilic colloid layer adjacent thereto.

The addition amount of the nucleating agent of the present invention is preferably from 1 μm to 10 mmol, more preferably from 10 μm to 5 mmol, and most preferably from 20 μm to 5 mmol, per 1 mol of silver halide.

In the present invention, the emulsion layer or the protective layer of the emulsion layer may be prepared as described in US Pat. Nos. 3,253,921, 2,274,782 and
Light absorbing materials and filter dyes as described in 2,527,583 and 2,956,879 can be used. Further, a dye can be mordant as described in, for example, US Pat. No. 3,282,699. The amount of the filter dye used is preferably from 0.1 to 3 at the exposure wavelength, particularly preferably from 0.2 to 1.5.

In the emulsion layer or the protective layer of the emulsion layer in the present invention, a matting agent such as starch, titanium dioxide, zinc oxide, silica, US Pat. Nos. 2,992,101 and 2,701,
Polymer beads, including beads of the type described in No. 245, can be included. The matte degree of the emulsion surface may be any value as long as stardust failure does not occur, but the Beck smoothness is preferably 200 seconds or more and 10,000 seconds or less, particularly 30 seconds.
It is preferably from 0 seconds to 10,000 seconds.

The photothermographic emulsion of the present invention is contained in one or more layers on a support. One layer must include the organic silver salt, silver halide, reducing agent (developer) and binder, and optional additional materials such as toning agents, coating aids and other auxiliaries. The two-layer construction is that the first emulsion layer (usually the layer adjacent to the support) contains an organic silver salt and silver halide, and the second layer or both layers do not contain some other components. No. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. It is also conceivable to have a first emulsion layer containing an organic silver salt, a second layer containing other components alone or distributed in both layers, and a three-layer structure containing a protective topcoat. The composition of the multicolor photothermographic material may include a combination of the two layers for each color,
Also, all components may be contained in a single layer as described in U.S. Pat. No. 4,708,928. In the case of a multi-dye, multi-color photothermographic material, each emulsion layer generally has a functional or non-functional layer between the emulsion layers (photosensitive layer) as described in U.S. Pat. No. 4,460,681. By using a barrier layer, they are kept distinct from each other.

Various dyes can be used in the photosensitive layer of the present invention from the viewpoint of improving color tone and preventing irradiation.
The dye used in the photosensitive layer of the present invention may be any dye, for example, pyrazoloazole dye, anthraquinone dye, azo dye, azomethine dye, oxonol dye, carbocyanine dye, styryl dye, triphenylmethane dye, indoaniline dye And indophenol dyes. Preferred dyes used in the present invention include anthraquinone dyes (e.g., compounds 1 to 9 described in JP-A-5-341441 and compound 3- described in JP-A-5-165147).
6-18 and 3-23-38), azomethine dyes (Japanese
5-341441 described compounds 17-47 etc.), indoaniline dyes (for example, compounds 11-19 described in JP-A-5-289227, compound 47 described in JP-A-5-341441, described in JP-A-5-165147) Compounds 2-10 to 11) and azo dyes (JP-A-5-3414)
No. 41, compounds 10 to 16). As a method for adding these dyes, a solution, an emulsion, a solid fine particle dispersion,
Any method such as a state in which it is mordanted with a polymer mordant may be used. The amount of these compounds to be used is determined depending on the intended absorption, but it is generally preferable to use them in an amount of 1 μg or more and 1 g or less per 1 m ^{2 of the} light-sensitive material.

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

When antihalation dyes are used in the present invention, such dyes have the desired absorption in the wavelength range,
Any compound may be used as long as it has a sufficiently low absorption in the visible region after the treatment and a desirable absorbance spectrum of the antihalation layer is obtained. For example, the following are disclosed, but the present invention is not limited thereto. As a single dye, JP-A-59-56458,
2-216140, 7-13295, 7114132, U.S. Patent 5,
No. 380,635, JP-A-2-68539, page 13, lower left column 1
From the line, p. 14, page 9, lower left column, line 9, ibid.
There are compounds described in the lower left column of the page to the lower right column of the same page 16 as the dyes which can be decolorized by the treatment, as described in JP-A Nos. 52-139136 and 53-132.
No. 334, No. 56-501480, No. 57-16060, No. 57-68831
No.57-101835, No.59-182436, JP-A-7-36145
No., No. 7-199409, No. 48-33692, No. 50-16648,
Japanese Patent Publication No. 2-41734, U.S. Pat.Nos. 4,088,497 and 4,283,48
No. 7, 4,548,896 and 5,187,049.

The photothermographic material of the present invention has at least one photosensitive layer containing a silver halide emulsion (emulsion layer) on one side of a support, and a back layer (backing layer) on the other side. It is preferable that the material is a so-called single-sided photosensitive material.

In the present invention, a matting agent may be added to the single-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. Patent Nos. 1,939,213, 2,701,245, and 2,322,037.
No. 3,262,782, No. 3,539,344, No. 3,767,448, etc.
No. 2,192,241, No. 3,257,206, No. 3,370,951, No.
Inorganic matting agents well-known in the art, such as inorganic matting agents described in the specifications such as 3,523,022 and 3,769,020 can be used. For example, specific examples of organic compounds that can be used as a matting agent include polymethyl acrylate, polymethyl methacrylate, polyacrylonitrile, and acrylonitrile as examples of water-dispersible vinyl polymers.
-α-methylstyrene copolymer, polystyrene, styrene-divinylbenzene copolymer, polyvinyl acetate, polyethylene carbonate, polytetrafluoroethylene, etc.Examples of cellulose derivatives such as methylcellulose, cellulose acetate, cellulose acetate propionate, etc. Examples of the derivative preferably include carboxystarch, carboxynitrophenyl starch, urea-formaldehyde-starch reactant, and the like, gelatin hardened with a known hardener, hardened gelatin coacervated and hardened into fine capsule hollow granules, and the like. Examples of the inorganic compound include silicon dioxide, titanium dioxide, magnesium dioxide, aluminum oxide, barium sulfate, calcium carbonate, silver chloride desensitized by a known method, silver bromide, glass, and diatomaceous earth. . 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. When implementing the present invention, 0.1 μm
It is preferable to use one 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 greatly affects the haze and surface gloss of the light-sensitive material, the particle size, shape, and particle size distribution can be changed as necessary during the preparation of the matting agent or by mixing a plurality of matting agents. preferable.

In the present invention, the matting degree of the back layer is preferably such that the Bekk smoothness is 250 seconds or less and 10 seconds or more, more preferably 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. It is preferable to be contained.

In the present invention, suitable binders for the back layer are transparent or translucent, generally colorless, and include natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as: gelatin, gum arabic, and poly (vinyl). (Alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (Styrene-maleic anhydride), copoly (styrene
-Acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (e.g., poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes), phenoxy resins, poly ( Vinylidene chloride), poly (epoxide) s,
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 emulsion.

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

US Pat. Nos. 4,460,681 and 4,374,921
Backside resistive heating layer (backside resist
ive heating layer) can also be used in the photothermographic image system of the present invention.

A hardener may be used for each layer such as the photosensitive layer, the protective layer and the back layer of the present invention. Examples of hardeners include:
U.S. Pat.No. 4,281,060, polyisocyanates described in JP-A-6-208193, etc., epoxy compounds described in U.S. Pat.
Vinyl sulfone compounds described in No. 48 and the like are used.

In the present invention, it is preferable to provide a water-resistant protective layer formed using a hydrophilic polymer or an aqueous emulsion. Such a water-resistant protective layer may also serve as a surface protective layer provided for the purpose of preventing adhesion of the above-mentioned image forming layer. Further, two or more protective layers may be provided, and at least one of the protective layers may be a water-resistant protective layer.

The water-resistant protective layer used in the present invention means that the formed protective layer has an elution rate of 50% or less when immersed in hot water at 35 ° C. for 2 hours and / or drops water drops. In this case, the contact angle is 60 degrees or more.
In the protective layer having an elution rate of more than 50% or a contact angle of less than 60 degrees when a water drop is dropped,
The infiltration of water and the occurrence of briefing in the photosensitive layer cannot be suppressed, resulting in a decrease in sensitivity and an increase in fog density. The lower limit of the elution rate is 0%, and the upper limit of the contact angle is 180%.
Degrees.

In the above, the elution ratio indicates the rate of decrease in the thickness of the protective layer due to immersion in hot water, and is the amount of decrease in the thickness of the protective layer reduced by elution with respect to the thickness of the protective layer before immersion in hot water. Is expressed as a percentage.

The hydrophilic polymer used in the present invention has a solubility of 1 g or more, preferably 5 g or more (upper limit) in 100 g of water, and has a water-resistant substituent on the side chain. Having a reactive group other than a hydroxyl group. Examples of the trunk polymer constituting the main chain include polyvinyl alcohol, polyethylene oxide, casein, starches, celluloses, gelatins, gum arabic, polyvinylpyrrolidone, acrylic acid (or methacrylic acid)
Examples thereof include, but are not limited to, an alkali salt of an ester copolymer, an alkali salt of a styrene / maleic anhydride copolymer, and a copolymer of acrylamide.

Further, examples of the water-resistant substituent include an aryl group such as an alkyl group and a phenyl group, and examples of the reactive group other than the hydroxyl group include a carboxyl group and an epoxy group.

Such a hydrophilic polymer exhibits solubility in water as described above at the time of preparing a coating solution, and cross-linking and the like progress by drying after formation of a coating film, thereby exhibiting water resistance. Yes, specifically, inert gelatin, polyethylene, polyvinyl alcohol, methyl cellulose and the like.

The aqueous emulsion used in the present invention refers to a dispersion in water in which a stable hydrophilic layer is formed around a water-insoluble resin.

As a method for obtaining the water-resistant protective layer of the present invention, as shown in Examples described later, 1,2- (bisvinylsulfonylacetamide) ethane is added to an aqueous solution of inert gelatin, and then coated and dried to obtain a water-resistant protective layer. In addition to obtaining a protective layer, there are the following.

1) Reactive surfactants, basic substances, reactive monomers, non-reactive surfactants, etc. on modified polyolefins such as polyolefins, chlorinated polyolefins, polyolefins modified with unsaturated carboxylic acids and / or acid anhydrides After adding the agent, it is dispersed in water, and polymerization is performed after adding the reaction initiator, whereby a stable hydrophilic layer is formed around the dispersed resin to form an emulsion, and this emulsion is applied and dried. Thereby, a water-resistant protective layer is formed.

2) A vinyl ester and an unsaturated compound having an epoxy group in the side chain are copolymerized in the presence of a radical polymerization initiator, and then saponified with an alkali catalyst in alcohol to obtain a resin. A water-resistant protective layer is formed by mixing a resin and a compound capable of reacting with an epoxy group, coating and drying.

3) A vinyl ester and an unsaturated compound having a fluorinated group in the side chain are copolymerized in the presence of a radical polymerization initiator, and then saponified with an alkali catalyst in alcohol to obtain a resin. An aqueous solution is applied and dried to form a water-resistant protective layer.

4) An aqueous solution of a water-soluble polysaccharide-based polymer compound is prepared and coated, and in a semi-solidified state, is brought into contact with a water-soluble metal salt solution and ion-exchanged to form a water-resistant protective layer.

In the above, examples of the formation of the water-resistant protective layer have been given.
It is not limited to these.

The content of the hydrophilic polymer used in the water-resistant protective layer in the protective layer is 20 to 10 with respect to the entire protective layer.
0% by weight is preferred. Further, when the resin is formed using the aqueous emulsion, the content of the resin derived from the aqueous emulsion in the protective layer is preferably in the same range.

Other compounds that can be contained in the protective layer include aldehydes, esters, isocyanates, and inorganic compounds that can react with a hydroxyl group, alcohols, phenols, mecaptans, and the like that can react with an epoxy group.
Carbazoles, pyrazoles, compounds having groups such as cyano group, isocyanate group, Kent group, cyanuric acid,
Phosgene, alkylamine, alkylamine hydrochloride, sulfonate and organic acid, pigment kaolin, clay,
Examples include talc, calcium carbonate, calcined clay, titanium oxide, diatomaceous earth, silica, aluminum silicate, magnesium silicate, and aluminum oxide, and an ultraviolet absorber, which can be contained. In addition, various compounds that may be contained in the above-mentioned protective layer can be contained.

The thickness of the water-resistant protective layer is preferably 0.1
μm to 20 μm, more preferably 0.3 μm to 10 μm
m.

As a method for obtaining the water-resistant protective layer of the present invention, an aqueous solution or an aqueous dispersion of an inert gelatin may be used, as described in Examples below, and the following methods may be used.

1) A reactive surfactant, a basic substance, a reactive monomer, a non-reactive surfactant, and a modified polyolefin such as a polyolefin, a chlorinated polyolefin, a polyolefin modified with an unsaturated carboxylic acid and / or an acid anhydride. After adding the agent, it is dispersed in water, and polymerization is performed after adding the reaction initiator, whereby a stable hydrophilic layer is formed around the dispersed resin to form an emulsion, and this emulsion is applied and dried. Thereby, a water-resistant protective layer is formed.

2) A vinyl ester and an unsaturated compound having an epoxy group in the side chain are copolymerized in the presence of a radical polymerization initiator, and then saponified with an alkali catalyst in alcohol to obtain a resin. A water-resistant protective layer is formed by mixing a resin and a compound capable of reacting with an epoxy group, coating and drying.

3) A vinyl ester and an unsaturated compound having a fluorinated group in the side chain are copolymerized in the presence of a radical polymerization initiator, and then saponified with an alkali catalyst in alcohol to obtain a resin. An aqueous solution is applied and dried to form a water-resistant protective layer.

4) An aqueous solution of a water-soluble polysaccharide-based polymer compound is prepared and applied, and in a semi-solidified state, is brought into contact with a water-soluble metal salt solution and ion-exchanged to form a water-resistant protective layer.

In the above, examples of the formation of the water-resistant protective layer have been given.
It is not limited to these.

The content of the hydrophilic polymer used in the water-resistant protective layer in the protective layer is 20 to 10 with respect to the entire protective layer.
0% by weight is preferred. Further, when the resin is formed using the aqueous emulsion, the content of the resin derived from the aqueous emulsion in the protective layer is preferably in the same range.

Other compounds that can be contained in the protective layer include aldehydes, esters, isocyanates, and inorganic compounds that can react with a hydroxyl group, alcohols, phenols, and mecaptans that can react with an epoxy group.
Carbazoles, pyrazoles, compounds having groups such as cyano group, isocyanate group, Kent group, cyanuric acid,
Phosgene, alkylamine, alkylamine hydrochloride, sulfonate and organic acid, pigment kaolin, clay,
Examples include talc, calcium carbonate, calcined clay, titanium oxide, diatomaceous earth, silica, aluminum silicate, magnesium silicate, and aluminum oxide, and an ultraviolet absorber, which can be contained. In addition, various compounds that may be contained in the above-mentioned protective layer can be contained.

The thickness of the water-resistant protective layer is preferably 0.1
μm to 20 μm, more preferably 0.3 μm to 10 μm
m.

In the present invention, a surfactant may be used for the purpose of improving coating properties and charging. As the surfactant, any surfactant such as nonionic, anionic, cationic, and fluorine can be used as appropriate. Specifically,
No. 62-170950, U.S. Pat.No.5,380,644, etc.
No. 188135, U.S. Patent
No. 3,885,965, etc.
Examples thereof include polyalkylene oxides and anionic surfactants described in JP-A-6-301140.

Examples of the solvent used in the present invention include New Solvent Pocket Book (Ohm Co., 1994), but the present invention is not limited thereto. The solvent used in the present invention has a boiling point of 40 ° C or more and 180 ° C or more.
C. or lower is preferred.

Examples of the solvent of the present invention include hexane, cyclohexane, toluene, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, ethyl acetate, 1,1,1-trichloroethane, tetrahydrofuran,
Triethylamine, thiophene, trifluoroethanol, perfluoropentane, xylene, n-butanol,
Phenol, methyl isobutyl ketone, cyclohexanone, butyl acetate, diethyl carbonate, chlorobenzene, dibutyl ether, anisole, ethylene glycol diethyl ether, N, N-dimethylformamide, morpholine,
Examples include propane sultone, perfluorotributylamine, and water.

The heat-developable photographic emulsion of the present invention can be coated on various supports. Typical supports include polyester films, primed polyester films, poly (ethylene terephthalate) films, polyethylene naphthalate films, cellulose nitrate films, cellulose ester films, poly (vinyl acetal) films, polycarbonate films and related or resinous Including 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 C 2-10 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 light-sensitive material of the present invention comprises an antistatic or conductive layer, for example, a soluble salt (eg, chloride, nitrate, etc.), a vapor-deposited metal layer, US Pat. No. 2,861,056 and US Pat.
It may have a layer containing an ionic polymer as described in US Pat. No. 206,312 or an insoluble inorganic salt as described in US Pat. No. 3,428,451.

A method for obtaining a color image using the photothermographic material of the present invention is described in JP-A-7-13295, page 10, left column.
There is a method described from the 43rd line to the 11th left column, 40th line. Also, as a stabilizer for color dye images, British Patent No. 1,326,889,
U.S. Patents 3,432,300, 3,698,909, 3,574,627
Nos. 3,573,050, 3,764,337 and 4,042,39
No. 4 illustrates this.

The photothermographic emulsions of the present invention can be coated by various 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 U.S. Pat. No. 2,761,791 and British Patent 837,095.

Additional layers in the photothermographic material of the present invention, such as a dye-receiving layer for receiving a moving dye image, an opaque layer if reflective printing is desired, and a primer layer known in the photothermographic art. 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 become another light-sensitive material.

The light-sensitive material of the present invention may be developed by any method, but is usually developed by raising the temperature of the light-sensitive material exposed imagewise. The preferred development temperature is 80 to
The temperature is 250 ° C, more preferably 100 to 140 ° C.
The development time is preferably from 1 to 180 seconds, more preferably from 10 to 90 seconds.

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

The light-sensitive material of the present invention has a low haze at the time of exposure and tends to cause interference fringes. Examples of this interference fringe prevention technology include a technology for obliquely entering a laser beam into a photosensitive material as disclosed in JP-A-5-113548 and a multi-mode laser disclosed in WO95 / 31754 and the like. There is known a method of utilizing these techniques, and it is preferable to use these techniques.

To expose the light-sensitive material of the present invention, SPIE vo
l.169 Laser Printing 116-128 (1979), JP-A-4-510
No. 43, WO95 / 31754, etc., it is preferable to expose the laser beams so that they overlap each other so that the scanning lines are not visible.

[0239]

Hereinafter, the present invention will be described with reference to Examples.
The present invention is not limited to these.

Example 1 (1) Preparation of Comparative Sample 1 (Method A) (Preparation of silver halide grains A) 22 g of phthalated gelatin and 30 mg of potassium bromide were dissolved in 700 ml of water, and the pH was adjusted at a temperature of 40 ° C. After adjusting to 5.0, an aqueous solution containing 18.6 g of silver nitrate 15
9 ml and an aqueous potassium bromide solution were added over 10 minutes by the control double jet method while keeping pAg 7.7. Then, 476 ml of an aqueous solution containing 55.4 g of silver nitrate, 8 μmol / liter of dipotassium hexachloride iridate and potassium bromide were added.
An aqueous solution containing 1 mol / liter was added over 30 minutes by the control double jet method while maintaining the pAg at 7.7.
Thereafter, the pH was lowered to perform coagulation sedimentation and desalting treatment, and 0.1 g of phenoxyethanol was added to adjust to pH 5.9 and pAg 8.0.
The obtained particles were cubic particles having an average particle size of 0.07 μm, a variation coefficient of projected area diameter of 8%, and a (100) plane ratio of 86%.

The temperature was adjusted with respect to the prepared silver halide grains A.
Raise the temperature to 60 ° C and use 85% sodium thiosulfate per mole of silver.
11 μmol of 2,3,4,5,6-pentafluorophenyldiphenylphosphine selenide and 2 μmol of the following tellurium compound 1, 3.3 μmol of chloroauric acid, and 230 μmol of thiocyanic acid were added. Aged for 120 minutes.

Thereafter, the temperature was changed to 40 ° C., and 3.5 × 10 ^-4 mol of the following sensitizing dye A was added to silver halide with stirring, and 10 minutes later, the mixture was rapidly cooled to 25 ° C. and halogenated. Preparation of silver particles A was completed.

[0243]

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[0244]

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(Preparation of Silver Crystalline Dispersion of Organic Acid) Behenic Acid
40 g, 7.3 g of stearic acid and 400 ml of water were stirred at a temperature of 90 ° C. for 15 minutes, 200 ml of 1N-NaOH was added over 15 minutes, 61 ml of a 1N aqueous nitric acid solution was added, and the temperature was lowered to 50 ° C. Next, 124 ml of a 1N aqueous solution of silver nitrate was added over 2 minutes, and the mixture was stirred for 30 minutes. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of the filtrate reached 30 μS / cm. The solid thus obtained was treated as a wet cake without drying, and 12 g of polyvinyl alcohol and 150 ml of water were added to a wet cake equivalent to 34.8 g of dry solid, and mixed well to form a slurry. Prepare 840 g of zirconia beads having an average diameter of 0.5 mm, put them in a vessel together with the slurry, and use a dispersing machine (1 G sand grinder mill:
Dispersion for 5 hours using an IMEX Co., Ltd.) and preparation of a microcrystal dispersion of silver organic acid as needle-like particles having an average minor axis of 0.04 μm, an average major axis of 0.8 μm, and a projected area variation coefficient of 30% by electron microscopic observation. Finished.

(Preparation of Material Solid Fine Particle Dispersion) Tetrachlorophthalic acid, 4-methylphthalic acid, 1,1-bis (2
-Hydroxy-3,5-dimethylphenyl) -3,5
Solid fine particle dispersions were prepared for 5-trimethylhexane, phthalazine, and tribromomethylphenylsulfone. 0.81 g of hydroxypropylmethylcellulose and 94.2 ml of water were added to tetrachlorophthalic acid, and the mixture was stirred well and left as a slurry for 10 hours. Thereafter, 100 g of zirconia beads having an average diameter of 0.5 mm was prepared, placed in a vessel together with the slurry, and dispersed for 5 hours using the same dispersing machine as used in the preparation of the silver salt of organic acid microcrystals to prepare tetrachlorophthalic acid. Was obtained. 70% by weight of the particle diameter was 1.0 μm or less. For other materials, the amount of the dispersant used and the dispersion time were changed to obtain the desired average particle size, and solid fine particle dispersions were obtained for each material.

(Preparation of Coating Solution for Emulsion Layer) To 500 g of LAKSTAR 3307B (manufactured by Dainippon Ink and Chemicals, Inc .; SBR latex) as a polymer latex, an organic silver microcrystal dispersion (silver 1 Mol), and the following materials were added with good stirring to obtain an emulsion coating solution.

Silver halide grains A 10 mol% of silver halide / equivalent to organic acid silver 10 g of tetrachlorophthalic acid 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-to Limethylhexane 98 g Phthalazine 9.2 g Tribromomethylphenylsulfone 12 g 4-Methylphthalic acid 14 g

Incidentally, Luckstar 3307B is a latex of a styrene-butadiene copolymer, and the average particle size of the dispersed particles is about 0.1 to 0.15 μm. Also,
The equilibrium water content determined as described below was 0.6% by weight.

(Preparation of Coating Solution for Emulsion Surface Protective Layer) For 10 g of inert gelatin, 0.26 g of the following surfactant A, 0.09 g of the following surfactant B, and silica fine particles (average particle size of 2.5
μm), 0.9 g, 1,2- (bisvinylsulfonylacetamido) ethane, 0.3 g, and water, 64 g, were added to form a surface protective layer.

[0251]

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(Preparation of Coloring Agent Dispersion) 35 g of ethyl acetate
2.5 g, 7.5 of the following compounds 1 and 2 respectively
g was added and stirred to dissolve. To the solution was added 50 g of a 10% by weight aqueous solution of polyvinyl alcohol previously dissolved, and the mixture was stirred with a homogenizer for 5 minutes. Thereafter, the ethyl acetate was volatilized by removing the solvent, and finally diluted with water to prepare a color former dispersion.

[0253]

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(Preparation of Coating Solution for Back Side) To 30 g of polyvinyl alcohol, 50 parts of the color former dispersion 50 previously prepared was prepared.
g, the following compound 20 g, water 250 g and Sildex H121 (Spherical silica manufactured by Dokai Chemical Co., Ltd., average size 12 μm)
m) 1.8 g was added to obtain a back surface coating solution.

[0255]

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(Preparation of Emulsion Layer Coating Sample) The emulsion layer coating solution prepared as described above was 175 colored with a blue dye.
silver 1.9g / m on μm polyethylene terephthalate support
After application to be ^2, the emulsion surface protective layer coating solution coated amount of gelatin was coated to a 1.8 g / m ² on the emulsion coating layer. After drying, a coating solution for the back surface was applied on the surface opposite to the emulsion layer so as to have an optical density of 0.7 at 660 nm to prepare a coating sample 1.

(2) Preparation of Sample with Modified Dye Addition Method (Method B) Coated samples were prepared except that the sensitizing dye was added not during the preparation of silver halide but after the addition of silver halide during preparation of the emulsion layer coating solution. Application sample 2 was prepared in the same manner as in 1.

(3) Preparation of a sample corresponding to the present invention (A
Method) In the preparation of silver halide emulsion A, after ripening for 120 minutes,
The temperature was changed to 40 ° C. and the sensitizing dyes in Table 1 (Example D-1)
The same method as for coating sample 1 except that 3.5 × 10 ^-4 mol was added to silver halide with stirring, and 10 minutes later, the mixture was rapidly cooled to 25 ° C. to complete the preparation of silver halide grains. A coating sample 3 was prepared.

[0259]

[Table 1]

[0260]

[Table 2]

(4) Preparation of sample corresponding to the present invention (B
Method) Coated Sample 4 was prepared in the same manner as for Coated Sample 3, except that the sensitizing dye was added after the silver halide was added during the preparation of the emulsion layer coating solution, not during the preparation of the silver halide.

(5) Preparation of the corresponding sample of the present invention (A
Method) In the preparation of silver halide emulsion A, after ripening for 120 minutes,
The temperature was changed to 40 ° C., and the sensitizing dyes shown in Table 1 were added while stirring at 3.5 × 10 ⁻⁴ mol with respect to the silver halide. After 5 minutes, the following compound 113 was added with 4.6 × 10 ^{− with} respect to the silver halide. After adding ³ mol and stirring for 5 minutes, coating sample 5 was prepared in the same manner as coating sample 1 except that the preparation of silver halide grains was terminated by quenching to 25 ° C.

[0263]

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(6) Preparation of Comparative Coating Sample for Protective Layer In preparing an emulsion surface protective layer coating solution, 0.26 g of surfactant A and 0.26 g of surfactant B were added to 10 g of polyvinyl alcohol in place of inert gelatin. 0.09 g and 0.9 g of silica fine particles (average particle size: 2.5 μm) were added to form a surface protective layer.

Except for the protective layer coating solution, the above (1) to
Coating was performed in the same manner using the coating liquid of (5) to prepare a coated sample.

The equilibrium water content of the binder used in the emulsion layer was determined as follows.

<Equilibrium Water Content> A solution (or dispersion) of the polymer used for the emulsion layer was applied on a glass plate and dried at 50 ° C. for 1 hour to obtain a polymer model film having a thickness of about 100 μm. The polymer model film thus obtained was peeled from the glass plate and conditioned in an atmosphere at 25 ° C. and 60% RH for 3 days, and the weight (W ₁ ) was measured. Then, the polymer model film was placed in a vacuum at 25 ° C. for 3 days, immediately put into a weighing bottle of which weight was known, and the weight (W ₀ = W ₃ −W ₂ ) was measured (W ₃ is the weight of the polymer model film and the weight of the polymer model film). the weight of the bottle, W ₂ is the weight of the weighing bottle). Using W ₀ and W ₁ , the water content was determined by the following equation.

Equilibrium water content at 25 ° C. and 60% RH =
{(W ₁ −W ₀ ) / W ₀ } × 100 (%) The evaluation of the water resistance of the emulsion protective layer was judged from the elution rate and the contact angle.

<Dissolution Rate> After the sample was immersed in warm water of 35 ° C. for 2 hours, the cross section of the untreated sample was observed with a scanning electron microscope to determine the change in the thickness of the emulsion protective layer due to the immersion in warm water.

The elution rate was defined as t ₀ , the thickness of the emulsion protective layer of the untreated sample was defined as t _1, and the thickness of the emulsion protective layer after immersion in warm water was defined as t ₁ .
It was calculated according to the following equation. Elution rate (%) = [(t ₀ −t ₁ ) / t ₀ ] × 100

<Contact Angle> A water droplet was dropped on the emulsion surface protective layer of the sample, and the contact angle was measured by a known method. When at least one of an elution rate of 50% or less and a contact angle of 60 ° or more was satisfied, water resistance was excellent (O), and when both were not satisfied, water resistance was poor (X). The characteristics of the above coated samples were evaluated as follows.

(Evaluation of photographic performance) The coated sample was exposed at 30 ° to the normal with a laser sensitometer (maximum output: 500 mW) equipped with a 647 nm Kr laser, and the coated sample was exposed at 120 ° C. for 15 minutes. After developing for 2 seconds, the obtained image was evaluated by a densitometer. The measurement results are Dmin., Dmax.
And sensitivity (the reciprocal of the ratio of the exposure amount giving a density higher than Dmin. 1.0). The sensitivity of coating sample 1
The sensitivity in the development process at 120 ° C. was set to 100.

(Evaluation of Silver Tone) The silver tone of the image portion of the obtained sample was visually evaluated.

(Evaluation of storage stability over time) Each coated sample was cut into a size of 30.5 cm × 25.4 cm, and a round corner having a corner of 0.5 cm was formed. Each of these samples is placed at 25 ° C 50% RH
1 day, sealed one each in a bag made of moisture-proof material, further 35.1cm × 26.9cm × 3.0cm
And aged at 50 ° C. for 5 days (forced aging).
This sample was subjected to the same evaluations as those used for evaluation of photographic performance, and Dmin., Dmax., And sensitivity were evaluated.

(Evaluation of preservability of light-irradiated image area) A photosensitive material exposed and developed in the same manner as in the evaluation of photographic properties was stuck inside a glass window exposed to direct sunlight, and allowed to stand for one month. Was visually evaluated. A: There is almost no change. …: Slight change in color tone but not bothersome. Δ: Partial discoloration of the image is present but practically acceptable. ×: Dmin. Is discolored and the density cannot be increased.

(Evaluation of preservability of dark image portion) The state of the image after the photosensitive material exposed and developed in the same manner as in the evaluation of the photographic property was allowed to stand at 40 ° C. for one month under light shielding conditions, was visually evaluated according to the following criteria. did. A: There is almost no change. …: Slight change in color tone but not bothersome. Δ: Partial discoloration of the image is present but practically acceptable. ×: Dmin. Is discolored and the density cannot be increased. Table 1 shows the evaluation results.

As is clear from Table 1, it is understood that the sample of the present invention is excellent in photographic performance, preservability of unprocessed light-sensitive material, and image preservability of the processed sample.

The sample coated with a binder (polyvinyl alcohol) having poor water resistance of the protective layer is deteriorated in image storability, silver tone, and the like, but the sample using the dye of the present invention has a reduced range. Few.

Further, by combining the sensitizing dye of the general formula (I) or (II) with the compound of the general formula (X), the sensitizing dye of the general formula (I) or (II) can be compared with the sensitizing dye of the general formula (I) or (II) alone. And the photographic performance is improved.

[0280]

According to the present invention, it has good silver tone and photographic characteristics at the time of development, and there is no decrease in photographic performance over time.
Further, a photothermographic material having excellent image storability can be obtained.

Claims (8)

[Claims] 1. A photothermographic material having a photosensitive silver halide, a non-photosensitive organic silver salt and a binder on at least one surface of a support, wherein the photosensitive silver halide has the following general formula (I) or A photothermographic material which has been spectrally sensitized by a methine dye represented by the general formula (II) and wherein a main binder of a photosensitive layer containing a photosensitive silver halide is a polymer latex. General formula (I) In the general formula (I), Z ₁ , Z ₂ and Z ₃ represent an atom group necessary for forming a 5- or 6-membered nitrogen-containing heterocyclic ring. R
₁ and R ₃ represent an alkyl group, and R ₂ represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group. L _1, L
₂ , L ₃ , L ₄ , L ₅ , L ₆ , L ₇ , L ₈ and L ₉ represent a methine group. p ₁ and p ₂ represent 0 or 1.
n ₁ and n ₂ represent 0, 1, ₂ , 3 or 4. M ₁
Represents a charge-balancing counter ion, and m ₁ represents a number of 0 or more necessary to neutralize the charge of the molecule. General formula (II) In the general formula (II), Z ₄ , Z ₅ and Z ₆ each represent an atomic group necessary for forming a 5- or 6-membered nitrogen-containing heterocyclic ring. R
₄ represents an alkyl group, and R ₅ and R ₆ represent a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group. L ₁₀ , L
₁₁ , L ₁₂ , L ₁₃ , L ₁₄ and L ₁₅ represent a methine group. p
₃ represents 0 or 1. n ₃ and n ₄ are 0, 1, 2,
Represents 3 or 4. M ₂ represents a charge balancing counter ion;
₂ represents a number of 0 or more necessary to neutralize the electric charge of the molecule. 2. In the general formula (I), R ₁ , R
_{2, R 3, Z 1,} Z 2, Z 3, L 1, L 2, L 3, L
_At least one of ₄ , L ₅ , L ₆ , L ₇ , L ₈ and L ₉ has a thioether group, and in the general formula (II), R ₄ , R ₅ , R ₆ , Z ₄ , Z ₅ , Z ₆ , L ₁₀ ,
At least one of L ₁₁ , L ₁₂ , L ₁₃ , L ₁₄ and L ₁₅
2. The photothermographic material according to claim 1, wherein the photothermographic material has a thioether group. 3. In the general formula (I), R ₁ , R
₂ , at least one of R ₃ , Z ₁ , Z ₂ or Z ₃ has a thioether group, and in the general formula (II),
_{4, R 5, R 6,} Z 4, Z 5 and photothermographic material of claim 1 having at least one thioether group of Z _6. 4. The photothermographic material according to claim 2, wherein in the methine dyes represented by formulas (I) and (II), the heterocyclic ring having a thioether group is other than a quinoline nucleus or a pyridine nucleus. material. 5. A methine dye represented by the general formula (I)
Is represented by the following general formula (III):
Image-sensitive material. General formula (III)In the formula (III), Z₇ Is Z₁ Synonymous with Z₈ Is Z_Two Synonymous with
Z₉ Is a sulfur atom, a selenium atom or an oxygen atom. R
₇ Is R₁ Synonymous with R_Five Is R_Two Synonymous with R₉ Is R _Three Synonymous with
It is. L₁₆Is L₁ Synonymous with L₁₇Is L_Two Synonymous with L₁₈Is
L_Three Synonymous with L₁₉Is L_Four Synonymous with L₂₀Is L_Five Synonymous with L
_{twenty one}Is L₆ Synonymous with L_{twenty two}Is L₇ Is synonymous with p_Four Is p₁ 
Synonymous with n_Five Is n₁ Synonymous with n₆ Is n_Two Synonymous with M_Three Is
M₁ Synonymous with m_Three Is m₁ Is synonymous with Q is alkyl
Group, an aryl group, or a heterocyclic group. k₁ Is 1,
2, 3 or 4. 6. The polymer of the polymer latex,
The photothermographic material according to claim 1, wherein the equilibrium water content at 25 ° C. and 60% RH is 2% by weight or less. 7. The photothermographic material according to claim 1, further comprising a water-resistant protective layer formed using a hydrophilic polymer or an aqueous emulsion on the photosensitive layer. 8. The heat according to claim 1, wherein a photosensitive silver halide to which a methine dye represented by formula (I) or (II) is added in advance is prepared at the time of preparing a coating solution. Developed photosensitive material.