JPH09304868A - Wheat developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat developable photosensitive material less liable to a change in photographic performance even when development temp. is varied by incorporating photosensitive silver halide particles formed in the presence of a natural substance or a synthetic compd. having the properties of protective colloidal and other than gelatin. SOLUTION: This heat developable photosensitive material has an org. silver salt, photosensitive silver halide, a reducing agent for silver ions and a binder on the substrate and contains photosensitive silver halide particles formed in the presence of a natural substance or a synthetic compd. having the properties of protective colloid and other than gelatin. The silver halide particles have been mixed with the org. silver salt and have been spectrally sensitized with a sensitizing dye having absorption in an IR region. The natural substance is, e.g. starch, agar-agar or konjakmannan and the synthetic compd. is, e.g. a polyacylamide polymer or a polymer having thio-ether groups.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photothermographic material.

[0002]

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

A monosheet photosensitive material for heat treatment containing a photosensitive silver halide grain is a non-photosensitive reducing silver source, a photosensitive material which produces silver when irradiated, and a reducing agent for the silver source. Is basically contained.

In general, the photosensitive material must be in catalytic proximity to the non-photosensitive source of reducing silver. Catalytic proximity refers to the close proximity of these two materials so that when silver nuclei are formed by irradiation or exposure to photographic silver halide, these nuclei can catalyze the reduction of the silver source by the reducing agent. Having a physical relationship. It has been understood for many years that silver is a catalyst for the reduction of silver ions and that the photosensitive silver halide catalyst precursor that produces silver can be placed in catalytic proximity with the silver source in many different ways. It was For example, partial metathesis of a silver source using a halide-containing source (eg, US Pat. No. 3,457,075), mixing silver halide with a silver source material (eg, US Pat. No. 3,839,
049), and all other methods of closely relating the silver halide to the silver source.

Gelatin has been used as a protective colloid for silver halide photographic emulsions used for image formation of photographic light-sensitive materials and has been used up to now. The main reasons for this are mainly that the protective colloid property is large, and secondly that the sol-gel conversion is easy and the handling is easy and coating is possible.

However, when a light-sensitive material is prepared by mixing a silver halide and a silver source material, the dispersibility of silver halide in the light-sensitive material is poor and the fluctuation of photographic performance due to the fluctuation of the development temperature is greatly improved. Was desired.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photothermographic material which exhibits small photographic performance even when the development temperature is changed.

[0008]

The present invention has achieved the above object by the method described below.

(1) In a photothermographic material having an organic silver salt, a photosensitive silver halide, a reducing agent for silver ions and a binder on a support, a natural product or synthetic compound having a protective colloid property other than gelatin. A photothermographic material, which is the photosensitive silver halide grain formed in the presence of

(2) Absorption in the infrared region, which is characterized by mixing photosensitive silver halide grains formed in the presence of a natural or synthetic compound having a protective colloidal property other than gelatin with an organic silver salt. A photothermographic material spectrally sensitized by a sensitizing dye having

(3) Containing the photosensitive silver halide grain formed in the presence of a polymer having a repeating unit derived from an ethylenically unsaturated monomer having at least one thioether structure in its side chain. The photothermographic material according to (1) or (2), characterized by

(4) The photosensitive silver halide grain contains at least one metal complex of a metal selected from rhodium, ruthenium, osmium, rhenium, iridium, cobalt or iron (1) to ( 3) The photothermographic material according to any one of items.

(5) The photothermographic material according to any one of (1) to (4), wherein the photosensitive silver halide grain is a grain chemically sensitized with a chalcogen compound.

(6) The heat according to any one of (1) to (5), wherein the average grain size of the photosensitive silver halide grains is in the range of 0.01 μm or more and 0.13 μm or less. Development photosensitive material.

(7) The photothermographic material according to any one of (1) to (6), which is coated on a transparent support.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The components of the present invention will be described in detail below. One. Natural products other than gelatin having protective colloid properties Typical examples of the natural compounds described in the present invention include starch, agar, konjak mannan, carrageenan, etc. The present invention is not limited to these, and may include those obtained by graft-polymerizing starch with acrylic acid. Further, these natural products may exist alone or in combination of two or more kinds. The molecular weight and the molecular weight distribution of the natural compound are not limited and can be arbitrarily selected according to the purpose. The amount used is preferably 0.1 mg or more and 1 kg or less, more preferably 0.5 mg or more and 500 g or less, still more preferably 1 mg or more and 150 g or less, per mol of silver. British Patent 542704
No. 5,516,59, US Pat. Nos. 2,127,573, 23,11086, and 2,322,085 each describe a derivative of cellulose or starch.

2. Synthetic Compounds Having Protective Colloidal Properties Representative examples of the synthetic compounds described in the present invention are shown below, but the synthetic compounds having protective colloidal properties are not limited to the following. A. Polyacrylamide Polymer A homopolymer of acrylamide, US Pat. No. 254147.
No. 4, a copolymer of polyacrylamide and imidized polyacrylamide, West German Patent 120
No. 2132, a copolymer of acrylamide and methacrylamide, a partially aminated acrylamide polymer shown in US Pat. No. 3,284,207, JP-B-45-14031, US-371.
No. 3834, No. 3746548, British Patent 78834
No. 3 Substituted acrylamide polymer shown in each specification. B. Amino Polymer US Pat. Nos. 3,345,346, 3,706,504 and 4,
No. 350759, West German Patent No. 2138872, amino polymers shown in each specification, British Patent No. 1413125
4 shown in each specification of U.S. Pat. No. 3,425,836
Polymers having a primary amine, polymers having an amino group and a carboxyl group shown in U.S. Pat. No. 3,511,818, polymers shown in U.S. Pat. No. 3,832,185. C. Polymer Having Thioether Group US Pat. Nos. 3,615,624, 3,860,428 and 3,
No. 706564, a polymer having a thioether group shown in each specification. D. Polyvinyl alcohol Homopolymer of polyvinyl alcohol, US Patent 300
No. 0741 of organic acid monoesters of polyvinyl alcohol, US Pat. No. 3,236,653, maleic acid esters of US Pat. No. 3,479,189.
A copolymer of polyvinyl alcohol and polyvinylpyrrolidone shown in the specification.

E. Acrylic acid polymer Acrylic acid homopolymer, US Pat. No. 3,832,185,
No. 3852073, Acrylic ester polymers having amino groups shown in US Pat. No. 4,131,147.
Halogenated acrylic acid ester polymers shown in No. 1 and cyanoalkyl acrylic acid esters shown in US Pat. No. 4,120,727. F. Polymers having hydroxyquinoline Polymers having hydroxyquinoline shown in U.S. Pat. Nos. 4,030,929 and 4,152,161. G. FIG. Acetal US Pat. Nos. 2,358,836, 3,0038,79 and 2,
The polyvinyl acetal shown in each specification of 828204, British Patent 771155.

H. Polyvinylpyrrolidone Homopolymer of vinylpyrrolidone, French patent 203
A copolymer of acrolein and pyrrolidone shown in 1396. I. Polystyrene Polystyrylamine polymers shown in U.S. Pat. No. 4,315,071 and halogenated styrene polymers shown in U.S. Pat. No. 3,861,918. J. Imidazole polymer JP-B-43-7561, 47-25374, 5
No. 2-16365, German Patent 2012095
Nos. 1,202,970, and polymers having vinylimidazole groups shown in the respective specifications. K. Others A vinyl polymer having an azaindene group shown in JP-A-59-8604, a polyalkylene oxide derivative shown in U.S. Pat. No. 2,976,150, a polyvinylamine imide polymer shown in U.S. Pat. No. 4,022,623, and U.S. Pat. No. 4,294,920. Issue 408
9688 Polymers shown in US Pat.
No. 84456, polyvinyl pyridine, US Pat. No. 3,520,857, imidazole group-containing vinyl polymer, JP-B No. 60-658, Japanese Patent Publication No. 29. No. 1 polyvinyl-2-methylimidazole and acrylamide-imidazole copolymers shown on page 18, dextran, Zeitschrift Bisen-Schaftlie Photography Vol. 45, page 43 (1950), water-soluble polyalkyleneaminotriazoles Etc.

Further, in the present invention, a polymer having a repeating unit derived from an ethylenically unsaturated monomer containing at least one thioether structure in its side chain is particularly effective. A preferred example of the polymer containing at least one thioether structure is a polymer containing a repeating unit derived from an ethylenically unsaturated monomer having a thioether structure in the side chain as represented by the following general formula (1). A compound can be mentioned.

[0021]

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In the above formula, R ¹ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a chlorine atom. L ¹ is -
^{CON (R 2) - (R} 2 represents a hydrogen atom, an alkyl group or a substituted alkyl group having 1 to 6 carbon atoms having 1 to 4 carbon atoms.), - COO -, - NHCO -, - OCO-,

[0023]

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(R ³ and R ⁴ each independently represent a hydrogen atom, a hydroxyl group, a halogen atom or a substituted or unsubstituted alkyl group, alkoxy group, acyloxy group or aryloxy group),

[0025]

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(R ² , R ³ and R ⁴ are as defined above). L ² represents a linking group connecting L ¹ and R, and contains at least one thioether bond. i represents 0 or 1, and j represents 1 or 2. R represents a monovalent substituent. L above
^The linking group containing at least one thioether bond represented by ² is specifically represented by the following formula.

[0027]

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In the above equation, J¹ , J^Two , J^Three And J
^Four May be the same or different, -CO-,
-SO_Two -, -CON (R^Five )-(R^Five Is hydrogen atom, charcoal
Alkyl groups having 1 to 6 primes or substituted alkyl groups having 1 to 6 carbons
Kill group), -SO_Two N (R^Five)-(R^Five Is synonymous with the above
Yes, -N (R^Five ) -R⁶ − (R^Five Is synonymous with the above
R⁶ Represents an alkylene group having 1 to 4 carbon atoms),-
N (R^Five ) -R⁶ −N (R⁷ )-(R^Five And R⁶ Is it
Each has the same meaning as above and R⁷ Is a hydrogen atom, having 1 to 6 carbon atoms
Or an alkyl group having 1 to 6 carbon atoms
Represent), -0-, -S-, -N (R^Five ) -CO-N (R
⁷ )-(R^Five , R⁷ Are synonymous with the above. ),
−N (R^Five ) -SO_Two N (R⁷ )-(R^Five , R⁷ Is
Each has the same meaning as above), -COO-, -OCO-,
−N (R^Five ) CO_Two − (R^Five Is synonymous with the above),
−N (R^Five ) CO- (R^Five Is the same as above)
You. X above¹ , X^Two , X^Three And X^Four Are the same
May be different, alkylene group, substituted alkylene
Group, arylene group, substituted arylene group, aralkylene
Represents a group or a substituted aralkylene group. p, q, r are 0
Or represents 1. However, p, q, and r must be 0 at the same time.
And not. X above¹ , X^Two , X^Three And X^Four Are the same as each other
May be the same or different, and may be unsubstituted with 1 to 10 carbon atoms
Or substituted, alkylene, aralkylene, or fluoro groups.
Represents an enylene group, and the alkylene group may be linear or branched.
Is also good. Examples of the alkylene group include methylene and me
Tylmethylene, dimethylmethylene, dimethylene, trime
Tylene, tetramethylene, pentamethylene, hexamethy
Mention may be made of len and decyl methylene. Aral
Examples of the xylene group include benzylidene.
Can be. As a substituted or unsubstituted phenylene group
Is, for example, p-phenylene, m-phenylene, and
Chillphenylene can be mentioned. Also above X¹ ,
X^Two , X^Three And X^Four An alkylene group represented by
The following groups are available as substituents for the xylene or phenylene groups:
Or it may be an atom. Halogen atom, nit
Group, cyano group, alkyl group, substituted alkyl group, alcohol
Xy group, substituted alkoxy group, -NHCOR⁸ (R⁸ Is
Alkyl group, substituted alkyl group, phenyl group, substituted phenyl group
Represents an alkyl group, an aralkyl group, or a substituted aralkyl group. ),-
NHSO_Two R⁸ (R⁸ Is synonymous with the above), -SO
R⁸ (R⁸ Is synonymous with the above), -SO_Two R⁸ (R
⁸ Is synonymous with the above), -COR⁸ (R ⁸ Above
Synonymous with), a group represented by the following formula,

[0029]

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(R ⁹ and R ^{10, which} may be the same or different, each represents a hydrogen atom, an alkyl group, a substituted alkyl group, a phenyl group, a substituted phenyl group, an aralkyl group or a substituted aralkyl group), A group represented by the formula,

[0031]

[Chemical 6]

(R⁹ And R^TenAre respectively synonymous with the above
is there. ), An amino group (may be substituted with an alkyl group
A), a hydroxyl group, a group which is hydrolyzed to form a hydroxyl group. this
When they have two or more substituents, they are
It may be the same or different. None of the substituents described above
, Further having a substituent, a substituted alkyl group, a substituted alkyl group
Placement of a Coxy group, a substituted phenyl group or a substituted aralkyl group
Examples of the substituent include a halogen atom, a cyano group, and hydroxyl group.
Group, nitro group, alkoxy group having 1 to 4 carbon atoms, -NHS
O_Two R⁸ (R⁸ Is as defined above), -NHCOR
⁸ (R⁸ Is synonymous with the above), the above (5), (6)
A group represented by_Two R⁸ (R⁸ Is synonymous with the above
), -COR⁸ (R⁸ Is synonymous with the above),
Group (which may be substituted with an alkyl group)
You. R represents a monovalent substituent, specifically, having 1 carbon atom
To 20 substituted or unsubstituted alkyl groups, or carbon number
It represents a 6-20 substituted or unsubstituted aryl group. Al
Specific examples of the kill group include methyl, ethyl, and n-propyl.
Ropyr, isopropyl, n-butyl, t-butyl, n-
Hexyl, n-octyl, n-dodecyl and the like can be mentioned.
You. Further, as a substituent of the above alkyl group and aryl group
Is the above X¹ , X^Two , X^ThreeAnd X^Four Same as explained in
A halogen atom, a nitro group, a cyano group, an alkyl group,
Substituted alkyl group, alkoxy group, substituted alkoxy group,-
NHCOR⁸ (R⁸Is an alkyl group, a substituted alkyl group,
Phenyl group, substituted phenyl group, aralkyl group, substituted aralkyl group
Represents an alkyl group), -NHSO_Two R⁸ (R⁸ Is the same as above
Meaning), -SOR⁸ (R⁸ Is synonymous with the above),
-SO_Two R⁸ (R⁸ Is as defined above), -COR⁸ 
(R⁸ Is the same as the above), and is represented by the above (5).
Group (R ⁹ , R^TenMay be the same or different from each other,
Hydrogen atom, alkyl, substituted alkyl, phenyl, substituted fluorine
Phenyl, aralkyl, substituted aralkyl), above
The group represented by (6) (R⁹ , R^TenIs synonymous with the above
), An amino group (may be substituted with an alkyl group
Group), a group that forms a hydroxyl group by hydrolysis.
You can

Typical specific examples of the ethylenically unsaturated monomer which gives the repeating unit represented by the above formula (1) are shown below. 3-thiapentyl acrylate 2-thiabutyl acrylate 3-thiapentyl methacrylate 2-thiabutyl methacrylate N- (3-thiapentyl) acrylamide N- (3-thiabutyl) acrylamide N- (3-thiapentyl) methacrylamide 5-thiaheptyl acrylate N- (7-thiaheptyl) acrylamide N- (3-thiaoctyl) acrylamide N- (7-thianonyl) acrylamide N- (2,5-dimethyl-4-thiahexyl) methacrylamide N-acryloylmethionine N-methacryloylmethionine N- acryloyl methionine methyl ester N- (3,6-dithiaheptyl) acrylamide N- [2,2-bis (1-thiapropyl) ethyl] acrylamide _{CH 2 = CH-COOCH 2 CH} 2 OCOCH 2 CH 2 COOCH 2 CH 2 SCH ₂ CH ₃ Formula (7) below

[0034]

[Chemical 7]

[0035] 3-thiapentyl-4-vinyl benzoate _{CH 2 = CH-CONHCH 2 COOCH} 2 CH 2 SCH 2 CH 3 CH 2 = CH-CONH (CH 2) 3 COOCH 2 CH 2 SCH 2 CH 3

The polymer having the repeating unit represented by the above formula (1) is preferably water-soluble, and if necessary, other ethylenically unsaturated monomer may be copolymerized.
Particularly preferred copolymerizable ethylenically unsaturated monomers are those whose homopolymers are soluble in water, an aqueous acidic solution or an aqueous alkaline solution. In particular,
The following are mentioned. Nonionic monomers such as acrylamide, methacrylamide, N-methylacrylamide, N, N-dimethylacrylamide, N-acryloylmorpholine, N-ethylacrylamide, N-vinylpyrrolidone, and the like;

[0037]

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[0038]

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Monomers or salts thereof having an anionic group such as (for example, sodium salt, potassium salt, ammonium salt, etc.); N, N-diethylaminoethyl methacrylate, N, N-dimethylaminoethyl acrylate,
N, N-diethylaminoethyl acrylate, N-
(N, N-dimethylaminopropyl) acrylamide,
N- (N, N-dihexylaminomethyl) acrylamide, 3- (4-pyridyl) propyl acrylate,
Tertiary amines such as N-diethylaminomethylstyrene or a salt thereof (for example, hydrochloride, sulfate, acetate); or N, N, N-trimethyl-N-vinylbenzylammonium chloride, N, N, N-trimethyl -N-
(3-acrylamidopropyl) A monomer having a cationic group such as a quaternary ammonium compound such as ammonium chloride. Among these, a nonionic monomer or a monomer having an anionic group is particularly preferred.

Further, in the polymer having the repeating unit represented by the formula (1), another ethylenically unsaturated monomer may be copolymerized within the range not impairing the water solubility. Such monomers include, for example, ethylene, propylene, 1-butene, isobutene, styrene, α-methylstyrene, vinyl ketone, monoethylenically unsaturated esters of aliphatic acids (eg, vinyl acetate, allyl acetate), Ester of ethylenically unsaturated monocarboxylic acid or dicarboxylic acid (for example, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, n-butyl acrylate, n-hexyl acrylate , 2-ethylhexyl acrylate), monoethylenically unsaturated compounds (for example, acrylonitrile) or dienes (for example, butadiene, isoprene). In the polymer containing the repeating unit represented by the above formula (1), the ratio of the monomer containing a thioether bond varies depending on the structure of the monomer, the purpose of use, and the like.
To 100% by weight, particularly preferably 1
７０70% by weight.

Preferred specific examples of the polymer having the repeating unit represented by the formula (1) are shown below, but the invention is not limited to these examples. (P-1) 3-Thiapentyl acrylate / 2-acrylamide-2-methylpropanesulfonic acid sodium copolymer (1/1 molar ratio) (P-2) 3-Thiapentyl acrylate / 2-acrylamido-2-methyl Sodium propanesulfonate copolymer (1/2 molar ratio) (P-3) Sodium 3-thiapentyl acrylate / 2-acrylamido-2-methylpropanesulfonate copolymer (1/3 molar ratio) (P-4 ) 3-Thiapentyl acrylate / 2-acrylamide-2-methylpropanesulfonic acid sodium copolymer (1 / 4.5 molar ratio) (P-5) 3-Thiapentyl acrylate / 2-acrylamide-2-methylpropanesulfone Sodium acid copolymer (1/6 molar ratio) (P-6) 3-thiapentyl acrylate / 2-act Sodium luamido-2-methylpropanesulfonate copolymer (1/9 molar ratio) (P-7) 3-thiapentyl acrylate / 2-acrylamido-2-methylpropanesulfonic acid sodium copolymer (1/12 molar ratio) ) (P-8) 3-thiapentyl acrylate / 2-acrylamido-2-methylpropane sulfonate sodium copolymer (1/24 molar ratio) (P-9) 3-thiapentyl methacrylate / 2-acrylamido-2- Sodium methyl propane sulfonate copolymer (1/1 molar ratio) (P-10) 3-thiapentyl methacrylate / 2-acrylamido-2-methyl propane sodium sulfonate copolymer (1/6 molar ratio) (P- 11) 2-Thiabutylacrylamide / 2-acrylamido-2-methylpropanesulfonic acid sodium salt Lithium copolymer (1/6 molar ratio) (P-12) 3-Thiapentyl acrylate / acrylic acid / sodium acrylate copolymer (1/3/3 molar ratio) (P-13) 3-Thiapentyl acrylate / Acrylamide copolymer (1 / 12.5 molar ratio) (P-14) N- (3-thiapentyl) acrylamide / acrylamide / sodium acrylate copolymer (1
(P-15) 2-thiabutyl acrylate / methyl methacrylate / 2-acrylamide-2-methylpropane sodium sulfonate copolymer (1/1/5 molar ratio) (P-16) N -(3-thiabutyl) acrylamide /
Sodium acrylate / sodium styrenesulfonate copolymer (1/4/4 molar ratio) (P-17) 3-thiapentyl acrylate / methyl acrylate / N, N-dimethylaminopropyl methacrylamide sulfate copolymer (1 (P-18) 3-thiapentyl 4-vinylbenzoate / N, N-dimethylaminomethylstyrene sulfate copolymer (1/5 molar ratio) (P-19) N-acryloylmethionine Na Salt / methyl methacrylate / 2-acrylamide-2-methylpropanesulfonic acid sodium copolymer (1/5/5 molar ratio) (P-20) N-acryloylmethionine methyl ester / 2-acrylamide-2-methylpropanesulfonic acid Sodium copolymer (1/6 molar ratio) (P-21) N- (3,6-dithiahe Chill) acrylamide / acrylamide / 2-acrylamido-2-methylpropanesulfonic acid sodium copolymer (1/5 /
6 molar ratio) (P-22) N- [2,2-bis (1-thiapropyl)
Ethyl] acrylamide / N-vinylpyrrolidone / 2-
Acrylamide-2-methylpropane sodium sulfonate copolymer (1 / 0.25 / 8 molar ratio)

The above-mentioned thioether structure-containing monomers and polymers are described, for example, in US Pat.
No. 615624, No. 3679425, No. 369275
No. 3, No. 3706564, etc., or Research Disclosure (Research Disclosure)
104, pp. 44-48 (1972), and can be synthesized according to the above-mentioned literature.

The polymer used in the present invention can be produced by various polymerization methods such as solution polymerization method, precipitation polymerization method, suspension polymerization method,
It can be performed by a bulk polymerization method. The method of initiating polymerization includes a method using a radical initiator, a method of irradiating light or radiation, and a thermal polymerization method. These polymerization methods and the method of initiating the polymerization are described, for example, in a revised version of “Polymer Synthesis Reaction” by Teiji Tsuruta (Nikkan Kogyo Shimbun, 1971). Among the above polymerization methods, a solution polymerization method using a radical initiator is particularly preferable. The solvent used in the solution polymerization method is water or, for example, ethyl acetate, methanol, ethanol, 1-propanol, 2-propanol, acetone, dioxane, N, N-dimethylformamide, N, N-dimethylacetoneamide, toluene, n
-Various organic solvents such as hexane and acetonitrile may be used alone or as a mixture of two or more thereof, or may be used as a mixed solvent with water.

The polymerization temperature needs to be set in relation to the molecular weight of the polymer to be produced, the kind of the initiator, etc., and can be from 0 ° C. or lower to 100 ° C., but usually 30 ° C. to 100 ° C.
Polymerizes in the range of Examples of the radical initiator used for the polymerization include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), and 2,2′-azobis (2-amidino propane)
Azo initiators such as dihydrochloride and 4,4′-azobis (4-cyano-pentanoic acid), and peroxide initiators such as benzoyl peroxide and potassium persulfate are preferable. The amount of the initiator is adjusted according to the molecular weight of the polymer, but is 0.
The range of 01 to 10 mol% is preferred, and particularly 0.01 to 10 mol%.
A range of 1.0 mol% is preferred. When synthesizing the polymer of the present invention in the form of a copolymer, all the monomers to be used may be initially placed in a reaction vessel, and an initiator may be added to perform polymerization. It is preferable to synthesize through a process of dropping the monomer into the polymerization medium. As the ethylenically unsaturated monomer to be dropped, two or more kinds of monomers used may be mixed and dropped, or may be dropped separately. Further, at the time of dropping, the ethylenically unsaturated monomer may be dissolved in a suitable auxiliary solvent. As the auxiliary solvent, water, an organic solvent (eg, methanol, ethanol, acetone, ethylene acetate, etc.) or a mixed solvent of water and the organic solvent may be used.

The time required for dropping depends on the polymerization reactivity of the ethylenically unsaturated monomer and the like, but is preferably 5 minutes to
8 hours, particularly preferably 30 minutes to 4 hours. The dropping speed may be constant throughout the dropping, or may be appropriately changed within the dropping time. When the ethylenically unsaturated monomers are separately dropped, the total dropping time and dropping rate of each can be freely changed as necessary. In particular, when the difference in polymerization reactivity between the ethylenically unsaturated monomers is large, a method of adding a monomer having high reactivity more slowly is preferable.

The polymerization initiator may be added to the polymerization solvent in advance, or may be added (dropwise) at the same time as the ethylenically unsaturated monomer. Alternatively, it may be dissolved in a solvent and added separately from the ethylenically unsaturated monomer. Also, two or more of such addition methods may be combined. The temperature at which the ethylenically unsaturated monomer is added is not particularly limited as long as the polymerization reaction can be caused, and varies depending on the type of the initiator and the type of the ethylenically unsaturated monomer.
° C, preferably 30-100 ° C, particularly preferably
It is in the range of 40-95 ° C.

The synthetic polymer compound containing at least one thioether bond in the present invention can be obtained by radical polymerization in the presence of mercaptans as described in JP-A-54-145522. A polymer may be mentioned. As described in “Oligomers” edited by Shinya Ogawara (Kodansha Scientific, 1976), pp. 10-30, the chain transfer reaction of polymer radicals to mercaptans and the formation of S radicals from S radicals are described. This is a method of generating a thioether structure at the polymer terminal by repeating the initiation and continuation of polymerization.

As the mercaptan used, n-butyl mercaptan, n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, 2-
Mercaptoethanol, 2-mercaptoethylamine, thiosalicylic acid, benzenethiol, thioglycolic acid, N- (2-mercaptoethyl) -cyclohexylamine, (2-mercaptoethyl) -trimethylammonium bromide or the corresponding acetate, Mercaptoaniline, 3-mercaptoaniline, 4-mercaptoaniline, mercaptoanisole, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole,
2-mercaptobenzoxazole, 2-mercapto-
4- (3H) -quinazolinone, 2-mercaptoquinoline, ethylmercaptoacetate, methylmercaptoacetate, 2-mercapto-1-methylimidazole,
Examples thereof include 2-mercapto-4-methylpyrimidine, 1-mercapto-3-phenylpropane, and 5-mercapto-1-phenyl-1,2,3,4-tetrazole.

As the preferred monomers used in the polymerization reaction, those homopolymers mentioned above are those soluble in water, an acidic aqueous solution or an alkaline aqueous solution. If necessary, a monomer containing a thioether bond or another ethylenically unsaturated monomer may be copolymerized.

Specific examples of such polymers are shown below in terms of the mercaptans used and the molar ratio of the monomers, but the compounds used in the present invention are not limited thereto. . (P-23) Mercaptoethanol / acrylamide /
Sodium 2-acrylamide-2-methylpropanesulfonate (1/500/10) (P-24) mercaptoethanol / acrylamide /
Sodium 2-acrylamide-2-methylpropanesulfonate (1/100/5) (P-25) hexyl mercaptan / acrylamide /
Sodium 2-acrylamido-2-methylpropanesulfonate (1/100/5) (P-26) Ethyl thioglycolate / methyl methacrylate / 2-sodium 2-acrylamido-2-methylpropanesulfonate (1/50/100) ( (P-27) Mercaptomeethanol / acrylamide (1/1000) (P-28) Octyl mercaptan / methyl methacrylate / acrylic acid / sodium acrylate (1/50 /
(P-29) bismercaptoethyl sulfide / acrylamide (1/1200) (P-30) bismercaptoethyl sulfide / acrylic acid / sodium acrylate (1/100/100) (P-31) mercaptoethanol / 3-thiapentyl acrylate / 2-acrylamide-2-methylpropane sodium sulfonate (1/15/100) (P-32) (n-) butyl thioglycolate / 3-thiapentyl acrylate / 2-acrylamide-2 -Sodium methylpropanesulfonate (1/10/10
0)

The polymer obtained by radical polymerization in the presence of the above mercaptans may be produced, for example, according to the method described in JP-A-54-145522. Basically, the same radical polymerization as in ordinary radical polymerization can be carried out except that it is used for mercaptans in addition to the monomer. Therefore, this kind of polymer can be produced according to the method for producing a polymer having a repeating unit represented by the above formula (1).

The molecular weight and molecular weight distribution of the synthetic compound having a protective colloid property usable in the present invention are not limited and can be arbitrarily selected according to the purpose. Further, these synthetic compounds can be used alone or in combination of two or more kinds. There is no limitation on the amount present, but it is preferably used in an amount of 0.1 mg or more and 1 kg or less, more preferably 0.5 mg or more and 500 g or less, still more preferably 0.5 mg or more per mol of silver, regardless of whether they are used alone or in combination. Is preferably present in an amount of 1 mg or more and 150 g or less.

The method of forming the photosensitive silver halide grains in the present invention is specifically performed in the presence of a natural product or a synthetic compound (protective colloid of the present invention) having a protective colloid property other than gelatin of the present invention. And a method of converting a part of silver of the organic silver salt into a photosensitive silver halide by adding a halogen-containing compound to the prepared organic silver salt,
A method of preparing a photosensitive silver halide grain by adding a silver-supplying compound and a halogen-supplying compound to the protective colloid solution of the present invention and mixing it with an organic silver salt can be used. In the present invention, the latter method can be preferably used. The grain size of the photosensitive silver halide is
For the purpose of suppressing white turbidity after image formation, it is preferably small, specifically 0.20 μm or less, more preferably 0.
01 μm or more and 0.13 μm or less, more preferably 0.02 μm or more
0.13 μm or less is preferable. Here, the grain size means the length of the edge of the silver halide grain when the silver halide grain is a cubic or octahedral so-called normal crystal. In the case where the silver halide grains are tabular grains, the diameter refers to a diameter when converted into a circular image having the same area as the projected area of the main surface. In the case of other than normal crystals, for example, in the case of spherical grains, rod-shaped grains, etc., it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

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

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

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

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

The photosensitive silver halide grains of the present invention are used in an amount of 0.1 mol of photosensitive silver halide per mol of organic silver salt.
01 mol is preferably 0.5 mol or less, more preferably 0.02 mol or more and 0.3 mol or less, and particularly preferably 0.03 mol or more and 0.25 mol or less. Regarding the mixing method and the mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide particles and organic silver salt are mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. There is a method of mixing, or a method of preparing an organic silver salt by mixing photosensitive silver halide prepared at any timing during the preparation of the organic silver salt,
There is no particular limitation as long as the effects of the present invention are sufficiently exhibited.

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

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

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

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

The reducing agent for silver ions of the present invention 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 should be present as 1-10% by weight of the imaging layer. In multi-layer constructions, a slightly higher percentage, about 2-15%, tends to be more desirable when the reducing agent is added to layers other than the emulsion layer.

A wide range of reducing agents for silver ions have been disclosed in the photothermographic materials utilizing organic silver salts. For example, amidoximes such as phenylamidooxime, 2-thienylamidooxime and p-phenoxyphenylamidooxime; for example, azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; 2,2-bis (hydroxymethyl) propionyl- A combination of an aliphatic carboxylic acid aryl hydrazide and ascorbic acid, such as a combination of β-phenylhydrazine and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (eg hydroquinone and bis (ethoxyethyl) ) Hydroxylamine,
A combination of piperidinohexose reductone or formyl-4-methylphenylhydrazine); hydroxamic acids such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-alininehydroxamic acid;
Combination of azine and sulfonamide phenol (eg, phenothiazine and 2,6-dichloro-4-benzenesulfonamide phenol); α such as ethyl-α-cyano-2-methylphenylacetate, ethyl-α-cyanophenylacetate -Cyanophenylacetic acid derivative; 2,2-
Dihydroxy-1,1-binaphthyl, 6,6-dibromo-2,2-dihydroxy-1,1-binaphthyl and bis (2-hydroxy
-1-Naphthyl) methane, such as bis-β-naphthol; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (eg, 2,4-dihydroxybenzophenone or 2,4-dihydroxyacetophenone) Combinations; such as 3-methyl-1-phenyl-5-pyrazolone, 5-pyrazolones; as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone Reductones; sulfonamide phenol reducing agents such as 2,6-dichloro-4-benzenesulfonamidephenol and p-benzenesulfonamidephenol;
2-phenylindane-1,3-dione, etc .; 2,2-dimethyl
Chroman, such as -7-t-butyl-6-hydroxychroman;
1,4-dihydropyridine such as 2,6-dimethoxy-3,5-dicarboethoxy-1,4-dihydropyridine; bisphenol (eg, bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4,4-ethylidene-bis (2-t-butyl-6-methylphenol), 1,1, -bis (2-hydroxy
-3,5-Dimethylphenyl) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl-4-hydroxyphenyl)
Propane, etc.); ascorbic acid derivatives (eg, 1-ascorbyl palmitate, ascorbyl stearate, etc.); and aldehydes and ketones, such as benzyl and biacetyl; 3-pyrazolidone and certain indane-1,3-diones; chromanol ( Such as tocopherol). Particularly preferred reducing agents are bisphenol and chromanol.

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

The heat-developable photographic emulsion of the present invention comprises one or more layers on a support. At least one layer must contain silver halide, and an organic silver salt,
It is preferred to include developers and binders and optional additional materials such as toning agents, coating aids and other auxiliaries. The two-layer construction comprises an organic silver salt and a silver halide in the first emulsion layer (usually the layer adjacent to the substrate),
Some other component must be included in the second layer or both layers. However, a two-layer construction comprising a single emulsion layer containing all components and a protective topcoat is also contemplated. The construction of a multicolor light-sensitive photothermographic material may include a combination of these two layers for each color, and US Pat.
All components may be contained in a single layer as described in 4,708,928. In the case of a multi-dye, multi-color photosensitive heat-developable photographic material, each emulsion layer is generally comprised of US Pat.
As described in No. 1, they are kept separate from each other by using a functional or non-functional barrier layer between each photosensitive layer.

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

Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazoline-5-
Quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and
Cyclic imides such as 2,4-thiazolidinedione; naphthalimides (eg, N-hydroxy-1,8-naphthalimide); cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4 -Triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5
-Mercaptans exemplified by diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole; N- (aminomethyl) aryldicarboximides;
(For example, (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-
Dicarboxyimide); and blocked pyrazoles, isothiuronium derivatives, and certain photobleaching agents (eg, N, N-hexamethylenebis (1-carbamoyl-
3,5-dimethylpyrazole), 1,8- (3,6-diazaoctane) bis (isothiuronium trifluoroacetate)
And 2-tribromomethylsulfonyl)-(benzothiazole)); and 3-ethyl-5 [(3-ethyl-2-benzothiazolinylidene) -1-methylethylidene] -2-thio-2,4-
Oxazolidinedione; phthalazinone, phthalazinone derivatives or metal salts, or 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 (such as phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride);
Phthalazine derivatives or metal salts, or derivatives such as 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine; phthalazine and phthalic acid derivatives (eg, phthalate) acid,
Quinazolinedione, such as 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride;
Benzoxazine or naphthoxazine derivatives; rhodium complexes that function not only as toning agents but also as a source of halide ions for silver halide formation in situ, eg ammonium hexachlororhodium (III), rhodium bromide, rhodium nitrate And potassium hexachlororhodium (III) ate; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide; 1,3-benzoxazine-2,4-dione, 8-methyl
-1,3-benzoxazine-2,4-dione and 6-nitro-
Benzoxazine-2,4-diones such as 1,3-benzoxazine-2,4-dione; pyrimidines and asymmetric-triazines (eg, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine 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 sensitizing dye in the present invention may be any one as long as it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains. As the sensitizing dye, a cyanine dye, a merocyanine dye, a complex cyanine dye, a complex merocyanine dye, a holo-holerocyanine dye, a styryl dye, a hemicyanine dye, an oxonol dye, a hemioxonol dye, and the like can be used. Useful sensitizing dyes for use in the present invention include, for example, RESEARCH DISCLOSURE Item 17
Item 643IV-A (p.23, December 1978), Item 1831X (1979)
August, p. 437). Especially various laser imagers, scanners,
A sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of a light source of an image setter or a plate making camera can be advantageously selected.

As an example of spectral sensitization having absorption in the red region, for He-Ne laser light sources, compounds I-1 to I-38 described in JP-A-54-18726, JP-A-6-38, -75322, compounds I-1 to I-35, compounds I-1 to I-34 described in JP-A-7-287338, and LED light sources described in JP-B-55-39818. Dyes 1 to 20, JP-A-62-284
Compounds I-1 to I-37 described in Japanese Patent No. 343 and JP-A-7-
Compounds I-1 to I-34 described in 287338 are advantageously selected.

In order to specifically spectrally sensitize a silver halide grain in any wavelength region in the infrared region (750 to 1400 nm), a photosensitive silver halide is added to cyanine, merocyanine, styryl, hemicyanine, A variety of known dyes, including oxonol, hemioxonol and xanthene dyes, can be spectrally favored for sensitization. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nuclei, oxazoline nuclei, pyrroline nuclei, pyridine nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei and imidazole nuclei. Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus. Including. Among the above cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective. For example, U.S. Pat.
761,279, 3,719,495, 3,877,943, British Patents 1,466,201, 1,469,117, 1,422,
No. 057, Japanese Patent Publication No. 3-10391, Japanese Patent Publication No. 6-52387, Japanese Patent Laid-Open No.
It may be appropriately selected from known dyes described in JP-A 5-341432, JP-A-6-194781 and JP-A-6-301141. A particularly preferred dye structure is a cyanine dye having a thioether bond, and examples thereof include JP-A-62-5823.
9, JP-A-3-138638, same 3-138642, same 4-255840, same 5-726
59, 5-72661, 6-222491, 2-230506, 6-25875
7, 6-317868, 6-324425, and cyanine dyes described in JP-A-7-500926.

These sensitizing dyes may be used alone,
Two or more kinds may be used in combination. Combinations of sensitizing dyes are often used, especially for supersensitization. Along with the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are Re.
search Disclosure Volume 176 Volume 17643 (Issued December 1978) No. 23
It is described in item J on page IV, Japanese Patent Publication Nos. 49-25500 and 43-4933, JP-A-59-19032 and 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 using water, methanol, ethanol, propanol, acetone, methylcellosolve, 2,2,3,3 -Tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-
A solvent such as methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2-propanol, N, N-dimethylformamide or the like may be dissolved in a single or mixed solvent and added to the emulsion.

Further, as disclosed in US Pat. No. 3,469,987, the dye is dissolved in a volatile organic solvent, the solution is dispersed in water or a hydrophilic colloid, and this dispersion is used as an emulsion. Addition method, Japanese Patent Publication No.
As disclosed in 44-27555, 57-22091, etc.,
Disclosed in U.S. Pat.Nos. 3,822,135 and 4,006,025, etc. are a method in which a dye is dissolved in an acid and the solution is added to the emulsion, or an acid or a base is coexistent to be added to the emulsion as an aqueous solution. As described in JP-A-53-102733 and JP-A-58-105141, a method of adding a solution in the form of an aqueous solution or a colloidal dispersion in which a surfactant coexists as described above, in a hydrophilic colloid. A method in which a dye is directly dispersed in the emulsion, and the dispersion is added to the emulsion, JP-A-51-746.
It is also possible to use a method in which a dye is dissolved using a compound that causes red shift and the solution is added to an emulsion as disclosed in No. 24. Also, ultrasonic waves can be used for the solution.

The sensitizing dye used in the present invention may be added to the silver halide emulsion of the present invention at any step in the preparation of emulsions which has heretofore been found to be useful. For example, U.S. Pat.Nos. 2,735,766 and 3,628,96
No. 4, No. 4,183,756, No. 4,225,666, JP-A-58
-184142, 60-196749, etc., the chemical ripening at the time before the grain formation step of silver halide and / or before desalting, during the desilvering step and / or after desalting. Before the start of the emulsion, as disclosed in the specification of JP-A-58-113920, the emulsion is coated immediately before the chemical ripening or during the process, after the chemical ripening, and before the coating. Before, it may be added at any stage in the process. Also, U.S. Pat. No. 4,225,666, Japanese Patent Laid-Open No. 58-762.
As disclosed in the specification of No. 9, etc., the same compound may be used alone or in combination with a compound having a different structure, for example, during the particle formation step and during the chemical ripening step or after the completion of the chemical ripening, The compound may be added in portions such as before aging or during the process and after completion, or may be added by changing the kind of compound to be added and the combination of compounds. Spectral sensitizing dye is photosensitive silver halide 1
It is preferably used in an amount of 10 ^-6 mol to 1 mol per mol, more preferably 10 ^-5 mol to 10 ^-2 mol.

In the present invention, a mercapto compound, a disulfide compound, and a thione compound are contained in order to suppress or accelerate the development and control the development, to improve the spectral sensitization efficiency and to improve the preservability before and after the development. be able to.

When the mercapto compound is used in the present invention, it may have any structure, but Ar-SM, Ar-SSA
Those represented by r are preferred. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or a condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, nafusuimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotelrazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine. , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring may be, for example, halogen (eg Br and Cl), hydroxy, amino, carboxy, alkyl (eg 1
From one or more carbon atoms, preferably those having 1 to 4 carbon atoms) and alkoxy (for example, one or more carbon atoms, preferably those having 1 to 4 carbon atoms) It may have one selected. Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-
Methylbenzimidazole, 6-ethoxy-2-mercaptobenzothiazole, 2,2'-dithiobis- (benzothiazole, 3-mercapto-1,2,4-triazole, 4,5-diphenyl-2-imidazolthiol, 2- Mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto
-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate , 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydrocicy-2-mercaptopyrimidine, 2-mercaptopyrimidine, 4,6 -Diamino-2-mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-1,2,4-triazole, 2-mercapto-4-phenyloxazole, etc. The invention is not limited to these.

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

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

In the emulsion layer or the protective layer for the emulsion layer in the present invention, US Pat. Nos. 3,253,921 and 2,274,782 are used.
No. 2,527,583 and 2,956,879 and can be used in photographic elements containing light absorbing materials and filter dyes. Alternatively, dyes can be mordant as described in, for example, US Pat. No. 3,282,699. The amount of the filter dye used is preferably such that the absorbance at the exposure wavelength is 0.1 to 3, and particularly preferably 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,
Polymeric beads, including beads of the type described in 701,245, and the like can be included. The matt degree of the emulsion surface may be any value as long as no stardust failure occurs, but the Beck smoothness is preferably from 1000 seconds to 10,000 seconds, particularly preferably from 2,000 seconds to 10,000 seconds.

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

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

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

Suitable binders for the backing layer in the present invention are transparent or translucent, generally colorless and include natural polymers such as synthetic resins, polymers and copolymers, and other film forming media such as: gelatin, gum arabic, poly (vinyl). Alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinylpyrrolidone), casein, starch, poly (acrylic acid), poly (methylmethacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (Styrene-maleic anhydride), copoly (styrene
-Acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (eg, 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 an emulsion.

In the present invention, the backing layer preferably has a maximum absorption in a desired wavelength range of 0.3 or more and 2 or less, more preferably an IR absorption of 0.5 or more and 2 or less and an absorption in the visible region of 0.00 or less. It is preferably 1 or more and less than 0.5, and more preferably 0.001 or more and 0.1.
Preferably, the antihalation layer has an optical density of less than 3.

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

US Pat. Nos. 4,460,681 and 4,374,
No. 921, a backside resistive heating layer (backside reheating
A sistive heating layer) can also be used in a photothermographic image system.

The silver halide emulsion of the present invention or /
And the organic silver salts can be further protected against the formation of additional fog and stabilized against loss of sensitivity during storage by antifoggants, stabilizers and stabilizer precursors. Suitable antifoggants, stabilizers and stabilizer precursors that can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716, U.S. Pat.Nos. 2,886,437 and 2,444,605. Azaindene, U.S. Pat.
728,663, mercury salts, U.S. Pat. No. 3,287,135, urazole, U.S. Pat. No. 3,235,652, sulfocatechol, U.K. Pat.No. 623,448, oximes, nitrones, nitroindazoles, U.S. Pat. ,
No. 405, polyvalent metal salts, U.S. Pat.No. 3,220,839, thyuronium salts, and U.S. Pat.
, Platinum and gold salts described in U.S. Pat. No. 4,597,915 and U.S. Pat. Nos. 4,108,665 and 4,442,20.
Halogen-substituted organic compounds described in US Pat. No. 4,12.
Nos. 8,557 and 4,137,079, 4,138,365 and 4,459,350, and the phosphorus compounds described in U.S. Pat. No. 4,411,985.

The photosensitive layer in the present invention contains a polyhydric alcohol as a plasticizer and a lubricant (see, for example, US Pat.
Glycerin and diols of the type described in 960,404), fatty acids or esters described in US Pat. Nos. 2,588,765 and 3,121,060, silicone resins described in British Patent 955,061 and the like.

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

In the present invention, a surfactant may be used for the purpose of improving coatability and charging. As the surfactant, any surfactant such as nonionic, anionic, cationic, and fluorine can be used as appropriate. Specifically,
62-170950, U.S. Pat. No. 5,382,504 and other fluorine-containing polymer surfactants, JP-A-60-244945, and JP-A-63
No. 188135, U.S. Patent
No. 3,885,965, etc.
Examples thereof include polyalkylene oxides and anionic surfactants described in JP-A-6-301140.

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

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

When the hydrazine nucleating agent is used in the present invention, it may be added to any of the silver halide emulsion layer on the organic silver salt emulsion layer side of the support or any other coating layer. Preferably, it is added to the organic silver salt emulsion layer or the coating layer adjacent thereto. The addition amount of the nucleating agent of the present invention is preferably 1 μm to 10 mmol, and 10 μm based on 1 mol of silver halide.
˜5 mmol is more preferred, and 20 μ-5 mmol is most preferred.

Although not required to practice the invention,
It may be advantageous to add a mercury (II) salt as an antifoggant to the emulsion layer. Preferred mercury (II) salts for this purpose are
Mercury acetate and mercury bromide. The photosensitive silver halide used in the present invention is generally 0.75 to 25 mol% of the organic silver salt.
, Preferably in the range of 2 to 20 mol%.

The photographic emulsion for heat development in the present invention can be coated on various supports, but a transparent support is more preferable. Typical supports include polyester film, subbed polyester film, poly (ethylene terephthalate) film, polyethylene naphthalate film, cellulose nitrate film, cellulose ester film, poly (vinyl acetal) film, polycarbonate film and related or resinous. Including materials, as well as glass and the like.

The light-sensitive material of the present invention comprises an antistatic or conductive layer such as a soluble salt (eg chloride, nitrate, etc.), a vapor-deposited metal layer, as described in US Pat. Nos. 2,861,056 and 3,206,312. A ionic polymer or a layer containing an insoluble inorganic salt or the like as described in U.S. Pat. No. 3,428,451.

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

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

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

The light-sensitive material of the present invention may be thermally developed by any method, but it is usually developed by raising the temperature of the image-wise exposed light-sensitive material. 80 is the preferred development temperature
It is ~ 250 ° C, more preferably 100-140 ° C. The developing time is preferably 1 to 180 seconds, more preferably 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. The laser light according to the present invention is preferably a gas laser, a YAG laser, a dye laser, a semiconductor laser or the like. Further, a semiconductor laser and a second harmonic generation element can be used.

[0104]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Example 1 (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 to 5.0 at 35 ° C., then silver nitrate 18.6.
159 ml of an aqueous solution containing g and an aqueous solution containing potassium bromide and potassium iodide in a molar ratio of 92: 8 were added over 10 minutes by the control double jet method while keeping pAg at 7.7. Then, an aqueous solution 47 containing 55.4 g of silver nitrate
6 ml, dipotassium hexachloroiridate and 10 μmol / l of potassium bromide and 1 mol / l of potassium bromide were added while maintaining the solution pAg of 7.7 over 30 minutes by the control double jet method. Thus, the preparation of silver iodobromide grains (iodine content core 8 mol%, average 2 mol%, average size 0.05 μm, projected area variation coefficient 8%, {100} plane ratio 85%) was completed.

The silver halide grains thus obtained were heated to 60 ° C. and 85 μmol of sodium thiosulfate and 11 μmol of 2,3,4,5,6-pentafluorophenyldiphenylphosphine selenide were added per mol of silver. 15 μmol of tellurium compound 1, 3.3 μmol of chloroauric acid and 280 μmol of thiocyanic acid were added, ripened for 120 minutes and then rapidly cooled to 30 ° C. to obtain a silver halide emulsion.

[0106]

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(Preparation of Silver Halide Grain B) In the preparation of silver halide grain A, acrylamide / acrylic acid / vinylimidazole / diacetone acrylamide (molar ratio of 60/7/6/23) was used instead of phthalated gelatin. Was added to 22 g to adjust the addition rate of an aqueous solution containing 18.6 g of silver nitrate.
%, And a cubic silver iodobromide grain B having a {100} face ratio of 89% was prepared.

(Preparation of Silver Halide Grains C to F) In the preparation of silver halide grains A, P-3, P-8, P-10 and P-19 described above were used instead of phthalated gelatin.
g, and the addition rate of an aqueous solution containing 18.6 g of silver nitrate was adjusted, except that silver halide grain C
~ F was prepared. The grain shape was the same as that of the silver halide grain A.

(Preparation of Organic Acid Silver Emulsions A to F) Stearic acid 1.3 g, arachidic acid 0.5 g, behenic acid 8.5
g, 300 ml of distilled water were mixed at 90 ° C. for 15 minutes, 31.3 ml of 1N-NaOH aqueous solution was added over 15 minutes with vigorous stirring, and the temperature was lowered to 30 ° C. Next, 7 ml of a 1N-phosphoric acid aqueous solution was added, 0.02 g of N-bromosuccinimide was added with vigorous stirring, and silver halide grains prepared in advance were added in an amount of 2.5 mmol of silver halide. Further, 25 ml of 1N-silver nitrate aqueous solution was added over 2 minutes, and stirring was continued for 90 minutes. Then, the solid content is filtered off by suction filtration, and the solid content of the filtered water is 30%.
It was washed with water until it became μS · cm. To the solid content thus obtained, 37 g of a 1.2 wt% butyl acetate solution of polyvinyl acetate was added and stirred, and the stirring was stopped and the mixture was left to separate into an oil layer and an aqueous layer. Obtained. Next, 20 g of a 2.5 wt% 2-butanone solution of polyvinyl butyral (Denka Butyral # 3000-K manufactured by Denki Kagaku Kogyo KK) was added to this oil layer and stirred. Furthermore, pyridinium bromide bromide 0.1 mmol and calcium bromide dihydrate 0.14 mmol were added together with 0.7 g methanol, and then 2-butanone 40 g and polyvinyl butyral (PVB B-76 manufactured by Monsanto Co.). 7.8 g of the above and dispersed by a homogenizer to obtain an organic acid silver salt emulsion (average minor axis 0.04 μm,
Needle-like particles having an average major axis of 1 μm and a coefficient of variation of 30% were obtained.

(Preparation of Emulsion Layer Coating Solution) Each chemical was added to the organic acid silver emulsion obtained above in the following amounts per mol of silver. At 25 ° C. sodium phenylthiosulfonate 10 mg, 65 mg dye 1, 30 mg dye 2, 2-mercapto-5-methylbenzimidazole 2 g, 4-chlorobenzophenone-2-carboxylic acid 21.5 g and 2-butanone 580 g, dimethyl. 220 g of formamide was added with stirring and left for 3 hours. Then, 8 g of 5-tribromomethylsulfonyl-2-methylthiadiazole,
2-tribromomethylsulfonylbenzothiazole 6
g, 4,6-ditrichloromethyl-2-phenyltriazine 5 g, disulfide compound 1 2 g, 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,
150 g of 5,5-trimethylhexane, 5 g of tetrachlorophthalic acid, 1.1 g of Megafax F-176P (a fluorine-based surfactant manufactured by Dainippon Ink and Chemicals, Inc.), 590 g of 2-butanone, and 10 g of methyl isobutyl ketone are stirred. While adding.

[0111]

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(Emulsion side protective layer coating liquid) CAB171-15S (cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.) 75
g, 4-methylphthalic acid 5.7 g, tetrachlorophthalic anhydride 1.5 g, phthalazine 13.0 g, 0.3 g of Megafax F-176P, Sildex H31 (Doikai Chemical Co., Ltd. true spherical silica average size 3 μm ) 2 g, sumidur N3500 (Sumitomo Bayer Urethane Polyisocyanate) 7 g 2
A solution prepared by dissolving 3070 g of 2-butanone and 30 g of ethyl acetate was prepared.

(Back Surface Coating Solution) Calcium Compound 1 was synthesized as follows. 0.08 mol of 3,5-di-tert-bu
Aqueous solution containing 0.019 mol of calcium chloride in 1 liter of ethanol solution containing tylcatechol 16
Add 7 ml and 125 ml of 25% aqueous ammonia and add 3 at room temperature.
Blow in air for a period of time and use bis 〔2- (3,5-di-tert-butyl-ob
enzoquinone monoimine) -4,6-di-tert-butyl phenolat
o] Calcium (II) crystals were precipitated. Polyvinyl butyral (Denka Butyral # 400 manufactured by Denki Kagaku Kogyo Co., Ltd.)
0-2) 12g, CAB381-20 (Eastman Chemical Co., Ltd.)
Cellulose acetate butyrate) 12g, 120mg of dye 1, 2
70 mg of calcium compound 1, 330 mg of dye 2, 5 mg
Dye 3, Sildex H121 (average spherical silica size 12 μm, manufactured by Dokai Chemical Co., Ltd.) 0.4 g, Sildex H51 (true spherical silica average size 5 μm, manufactured by Dokai Chemical Co., Ltd.) 0.4 g, 0.
1g of Megafax F-176P, 2g of sumidur N3500
2-butanone (500 g) and 2-propanol (500 g) were added with stirring to dissolve and mix.

[0114]

[Chemical 12]

The emulsion layer coating solution prepared as described above was coated on a 175 μm polyethylene terephthalate support tinted with a blue dye so that the amount of silver was 2.3 g / m ^2, and then on the side opposite to the emulsion layer. Back surface coating liquid 810
The coating was performed so that the optical density of nm was 0.7. Further, an emulsion surface protective layer coating solution was applied on the emulsion surface to a dry thickness of 2 μm. The smoothness (J.
The Beck's smoothness was examined using the Oken type smoothness measurement described in TAPPI Paper Pulp Test Method No. 5), and the emulsion side was 1000 seconds and the back side was 80 seconds.

[0116]

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(Evaluation of Photographic Performance) After exposing the photographic material with a laser sensitometer equipped with a 820 nm diode, the coated sample was developed at 115 ° C., 120 ° C. and 125 ° C. for 15 seconds to evaluate the obtained image. It was performed by a densitometer. The measurement results were evaluated by Dmin, Dmax, and sensitivity (the reciprocal of the ratio of the exposure dose that gives a density 1.0 higher than Dmin). The results are shown in Table 1. Regarding the sensitivity, the sensitivity of the coated sample 1 in the 120 ° C. development treatment was set to 100.

[0118]

[Table 1]

As is clear from Table 1, when the photosensitive silver halide grains formed in the presence of a compound having a protective colloidal property other than gelatin are used, the movement of photographic performance due to the difference in development temperature is very small. I understand.

Example 2 (Preparation of Photosensitive Silver Halide Grains G to N) In preparation of the photosensitive silver halide grains B of Example 1, polyvinyl alcohol was used instead of acrylamide / acrylic acid / vinyl imidazole / diacetone acrylamide. Silver halide grains GN were prepared in the same manner as silver halide except that the amount was changed to 22 g and the metal complexes shown in Table 2 were uniformly contained in the photosensitive silver halide grains.

[0121]

[Table 2]

The organic silver salt was prepared in the same manner as in Example 1.

(Preparation of Emulsion Layer Coating Solution) Each chemical was added to the organic acid silver emulsion obtained above in the following amounts per mol of silver. Sodium phenylthiosulfonate 10 mg, 75 mg dye a, 2-mercapto-5-methylbenzimidazole 2 g, 4-chlorobenzophenone-
21.5 g of 2-carboxylic acid, 580 g of 2-butanone and 220 g of dimethylformamide were added with stirring and left for 3 hours. Next, 8 g of 5-tribromomethylsulfonyl-2-methylthiadiazole, 6 g of 2-2-tribromomethylsulfonylbenzothiazole, 5 g of 4,6-ditrichloromethyl-2-phenyltriazine, 2 g of disulfide compound a, 1,1 -(2-hydroxy-
3,5-Dimethylphenyl) -3,5,5-trimethylhexane 160 g, tetrachlorophthalic acid 5 g, 2.3
g of hydrazine derivative a, Megafax F-176P (Dainippon Ink and Chemicals, Inc. fluorinated surfactant) 1.1
g, 2-butanone 590 g, methyl isobutyl ketone 1
0 g was added with stirring.

[0124]

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(Emulsion side protective layer coating liquid) CAB171-15S (cellulose acetate butyrate manufactured by Eastman Chemical Co., Ltd.) 75
g, 4-methylphthalic acid 5.7 g, tetrachlorophthalic anhydride 1.5 g, phthalazine 12.8 g, 0.3 g of Megafax F-176P, Sildex H31 (Doikai Chemical Co., Ltd. true spherical silica average size 3 μm ) 2g sumidur N3500 (Sumitomo Bayer Urethane Polyisocyanate) 6g 2-
What was dissolved in 3070 g of butanone and 30 g of ethyl acetate was prepared.

(Preparation of Support Having Back Surface) Polyvinyl butyral (Denka Butyral # 4000-2 manufactured by Denki Kagaku Kogyo KK) 6 g, Sildex H121 (spherical silica average size 12 μm manufactured by Dokai Chemical Co., Ltd.) 0 .2g, Sildex H5
1 (Dokai Chemical Co., Ltd. spherical silica average size 5 μm) 0.2
g, 0.1g of Megafax F-176P2-Propanol 6
4 g was added with stirring to dissolve and mix. Furthermore, 400 mg of dye a, 10 g of methanol and acetone 2
0 g of solution and 3-isocyanatomethyl-3,5,5
A solution of 1.2 g of trimethylhexyl isocyanate and 7 g of ethyl acetate was added to prepare a coating solution. A back surface coating solution was applied onto a polyethylene terephthalate film having a moisture-proof undercoat containing vinylidene chloride on both sides so as to have an optical density of 633 nm of 0.7.

[0127]

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The emulsion layer coating solution was coated on the support prepared as described above so that the silver content was 2 g / m ^2, and the emulsion surface protective layer coating solution was then dried to a thickness of 2 μm on the emulsion surface. Applied.

(Evaluation of Photographic Performance) After exposing the photographic material with a 633 nm He-Ne laser sensitometer, the photographic material was heated at 112 ° C.
And processed (developed) at 116 ° C. for 25 seconds. Further, the developed photographic material was irradiated with a halogen lamp for 15 seconds to erase the back dye. The image thus obtained was evaluated by a densitometer. The measurement results are Dmin, Dmax, sensitivity (Dmin
The reciprocal of the ratio of the exposure dose that gives a density higher than 3.0). Sensitivity is 1 at 116 ° C development processing of coated sample 7.
It was set to 00.

(Evaluation of storability in image area) The photosensitive material exposed and developed in the same manner as in the photographic evaluation was attached to the inside of a glass window exposed to direct sunlight and left standing for one month, and the appearance of the image was visually evaluated according to the following criteria. . ◎ ... There is almost no change. ○: There is a slight change in color tone, but it does not bother me. Δ: Practically acceptable although there is discoloration in the image area. ×: Dmin is discolored and the density cannot be increased. The results are shown in Table 3.

[0131]

[Table 3]

From Table 3, when the photosensitive silver halide grains formed in the presence of a compound having a protective colloidal property other than gelatin are used, the movement of the photographic performance due to the difference in development temperature is small, and the effect of the present invention is It can be seen that it is expressed.
Furthermore, it is understood that the effect of the present invention is further exhibited by incorporating the metal complex into the silver halide grain.

Example 3 (Preparation of photosensitive silver halide grains O to Y) In the preparation of photosensitive silver halide grains B of Example 1, silver nitrate 18.
The cubic silver iodobromide grains O to Y shown in Table 4 were prepared by appropriately changing the addition speed of the aqueous solution containing 6 g and the aqueous solution containing potassium bromide and potassium iodide and the temperature at which silver nitrate was added.
Was prepared.

[0134]

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[0135]

[Table 4]

(Preparation of Comparative Photosensitive Silver Halide Grain Z) Photosensitive silver halide grain Q was prepared in the same manner as photosensitive silver halide grain Q except that 22 g of inert gelatin was used instead of the synthetic compound having a protective colloid. Silver particles Z were prepared. Particle size is 0.07μm, dispersity is 84%
Met.

The organic silver salt emulsion, the emulsion layer coating solution, the emulsion surface protective layer coating solution, the back surface coating solution and the photographic performance were evaluated in the same manner as in Example 1.

[0138]

[Table 5]

The effects of the present invention are clear from Table 5. It was confirmed that when the silver halide grains were chemically sensitized by the chalcogen compound, they were sensitized. Further, it can be seen that the Dmax is high when the particle size is 0.01 μm or more and 0.13 μm or less.

[0140]

According to the present invention, fluctuations in photographic performance can be reduced even if the development temperature changes.

Claims (7)

[Claims] 1. A photothermographic material having an organic silver salt, a photosensitive silver halide, a reducing agent for silver ions and a binder on a support, which is a natural product or a synthetic compound having a protective colloid property other than gelatin. A photothermographic material comprising the photosensitive silver halide grains formed in the presence of the photothermographic material. 2. A light-sensitive silver halide grain formed in the presence of a natural or synthetic compound having a protective colloidal property other than gelatin is mixed with an organic silver salt to absorb light in the infrared region. A photothermographic material that is spectrally sensitized with a sensitizing dye. 3. A photosensitive silver halide grain formed in the presence of a polymer having a repeating unit derived from an ethylenically unsaturated monomer having at least one thioether structure in its side chain. The photothermographic material according to claim 1, wherein the photothermographic material is a photothermographic material. 4. Rhodium, ruthenium, osmium, rhenium, iridium in said photosensitive silver halide grain
4. The photothermographic material according to claim 1, containing at least one metal complex of a metal selected from cobalt and iron. 5. The photothermographic material according to claim 1, wherein the photosensitive silver halide grain is a grain chemically sensitized with a chalcogen compound. 6. The photothermographic material according to claim 1, wherein the photosensitive silver halide grains have an average grain size of 0.01 μm or more and 0.13 μm or less. . 7. The photothermographic material according to claim 1, wherein the photothermographic material is coated on a transparent support.