JP4048126B2 - Photothermographic material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a photothermographic material, and more particularly to a photothermographic material using a silver halide emulsion having a high silver iodide content. The sensitivity is greatly improved, and image storability after development processing is low. Relates to an excellent photothermographic material.
[0002]
[Prior art]
In recent years, in the medical field and the printing plate making field, dry development of photographic development processing is strongly desired from the viewpoint of environmental protection and space saving. In these areas, digitization has progressed, and image information is captured and stored on a computer, stored, and processed if necessary, and output to photosensitive materials by laser image setter or laser imager where necessary by communication. However, systems for developing and creating images on the spot are rapidly spreading. As a photosensitive material, it is necessary to form a clear black image that can be recorded by laser exposure with high illuminance and has high resolution and sharpness. As such digital imaging recording materials, various hard copy systems using pigments and dyes such as inkjet printers and electrophotography are distributed as general image forming systems, but the diagnostic ability is determined like medical images. It is unsatisfactory in terms of image quality (sharpness, graininess, gradation, color tone) and recording speed (sensitivity), and has not yet reached a level that can replace the conventional silver salt film for wet development.
[0003]
On the other hand, thermal image forming systems using organic silver salts are known (see, for example, Patent Documents 1 and 2 and Non-Patent Document 1). In particular, a photothermographic material generally contains a photosensitive silver halide, a reducing agent, a reducible silver salt (eg, an organic silver salt), and, if necessary, a toning agent for controlling the color tone of silver dispersed in a binder matrix. A photosensitive layer.
[0004]
The photothermographic material is heated to a high temperature (for example, 80 ° C. or higher) after image exposure, and is blackened by an oxidation-reduction reaction between silver halide or a reducible silver salt (functioning as an oxidizing agent) and a reducing agent. Form a silver image. The oxidation-reduction reaction is promoted by the catalytic action of the latent image of silver halide generated by exposure. As a result, a black silver image is formed in the exposed area. The photothermographic material is disclosed in many documents including, for example, Patent Documents 3 and 4, and in practical use, Fuji Medical Dry Imager FM-DP L is used as a medical image forming system. Released.
[0005]
In such an image forming system using an organic silver salt, since there is no fixing step, image storage stability after development processing, in particular, deterioration of printout when exposed to light has been a serious problem. As a means for improving this printout, a method using silver iodide formed by converting an organic silver salt is disclosed in patent documents (see, for example, patent documents 5 and 6). However, the method of converting an organic silver salt as disclosed herein with iodine cannot obtain sufficient sensitivity, and it is difficult to construct an actual system. Other photosensitive materials using silver iodide have been described in several patent documents, but none of them achieved sufficient sensitivity and fogging level, and did not endure practical use as a laser exposure photosensitive material. (See Patent Documents 7 to 11.)
[0006]
As means for increasing the sensitivity of a silver iodide photographic emulsion, it is possible to immerse in a halogen acceptor such as sodium nitrite, pyrogallol, hydroquinone or an aqueous silver nitrate solution in a scientific literature, or by sulfur sensitization with pAg7.5. , It was known to sensitize (see, for example, Non-Patent Documents 2 to 4). However, as shown in the Examples, the sensitizing effect of these halogen acceptors was very small and extremely insufficient in the photothermographic material targeted by the present invention. Therefore, development of a technique capable of greatly increasing the sensitivity in a photothermographic material using high silver iodide has been eagerly desired.
[0007]
On the other hand, in the production of a photothermographic material using an organic silver salt, a method of producing by a solvent coating and a method of producing by coating and drying a coating solution containing a polymer fine particle aqueous dispersion as a main binder are known. (For example, refer to Patent Document 12 and Patent Document 13.) Since the latter method does not require a process such as solvent recovery, the manufacturing equipment is simple and it is advantageous for mass production.
However, in a photothermographic material using a silver iodide photographic emulsion, it has been found that the use of polymer fine particles as a binder has a problem that the sensitivity is lower and the image density is lower, and further technical improvements are made. I was asked.
[0008]
[Patent Document 1]
U.S. Pat. No. 3,152,904
[Patent Document 2]
U.S. Pat. No. 3,457,075
[Patent Document 3]
U.S. Patent No. 2910377
[Patent Document 4]
Japanese Patent Publication No. 43-4924
[Patent Document 5]
US Patent No. 6143488
[Patent Document 6]
EP0922995
[Patent Document 7]
WO97-48014 Publication
[Patent Document 8]
WO48015 Publication
[Patent Document 9]
US Patent No. 6165705
[Patent Document 10]
JP-A-8-297345
[Patent Document 11]
Japanese Patent No. 2785129
[Patent Document 12]
JP 2002-229149 A
[Patent Document 13]
Japanese National Patent Publication No. 11-509332
[Non-Patent Document 1]
D. Klosterboer, “Thermally Processed Silver Systems” (Imaging Processes and Materials Neblette 8th Edition, Sturge, V. (Walworth, A. Shepp, edited, Chapter 9, 279, 1989)
[Non-Patent Document 2]
Journal of Photographic Science, 8, 119 pages, 1960
[Non-Patent Document 3]
Journal of Photographic Science, 28, 163, 1980
[Non-Patent Document 4]
Photographic Science and Engineering, Vol. 5, 216, 1961
[0009]
[Problems to be solved by the invention]
Accordingly, an object of the present invention is to provide a photothermographic material having high sensitivity and excellent image storage stability.
[0010]
1) In a photothermographic material containing a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent, and a binder on the same surface of a support,The photosensitive silver halide is grain-formed in the absence of the organic silver salt,The silver iodide content of the photosensitive silver halide is80 mol% or more100% by mole or less, and a monomer represented by the following general formula (M) as the binder is 10% by weight or more and 70% by weight or less.1% to 20% by mass of a monomer having an acid groupA photothermographic material comprising a copolymerized polymer latex.
  General formula (M)
    CH₂= CR⁰¹-CR⁰²= CH₂
  Where R⁰¹Represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom or a cyano group;⁰²Represents an alkyl group having 1 to 6 carbon atoms, a halogen atom, or a cyano group.
[0011]
2) The silver iodide content of the photosensitive silver halide is90The photothermographic material according to 1), wherein the photothermographic material is at least mol% and not more than 100 mol%.
3) The photothermographic material according to 1) or 2), wherein the average grain size of the photosensitive silver halide is from 5 nm to 80 nm.
4) The photothermographic material according to 1) or 2), wherein the average grain size of the photosensitive silver halide is from 5 nm to 40 nm.
5In the general formula (M), R⁰¹Is a hydrogen atom and R⁰²The photothermographic material according to any one of 1) to 4), wherein is a methyl group.
6) 1% by mass or more of the monomer having an acid group in the polymer latex10It is a polymer latex copolymerized by mass% or less 1) to5The photothermographic material according to any one of the above.
[0012]
7The glass transition temperature of the polymer latex is -30 ° C to 70 ° C.6)The photothermographic material according to any one of the above.
8The photothermographic material according to any one of 1) to 7), wherein the polymer latex has a glass transition temperature of −10 ° C. to 35 ° C.
9) The polymer latex contains 500 ppm or less of halogen ions per latex liquid 1) to8)The photothermographic material according to any one of the above.
10) The polymer latex is styrene-isoprene-Of monomers having acid groupsCopolymer latex 1) to9)The photothermographic material according to any one of the above.
11) The reducing agent is a compound represented by the following general formula (R):10)The photothermographic material according to any one of the above.
[0013]
Formula (R)
[Chemical Formula 3]
[0014]
  In general formula (R), R¹¹And R¹¹Each independently represents an alkyl group having 1 to 20 carbon atoms. R¹²And R¹²Each independently represents a hydrogen atom or a substituent that can be substituted on the benzene ring. L is a -S- group or -CHR¹³-Represents a group. R¹³Represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. X¹And X¹Each independently represents a hydrogen atom or a group capable of substituting for a benzene ring.
12In the reducing agent represented by the general formula (R), R¹¹And R¹¹Each is independently a secondary or tertiary alkyl group having 3 to 15 carbon atoms11)The photothermographic material described in 1.
131) to characterized by containing a development accelerator12)One of1 itemThe photothermographic material described in 1.
14The development accelerator contains a compound represented by the following general formula (A-1)13)The photothermographic material described in 1.
  Formula (A-1)
    Q₁-NHNH-Q₂
  (Where Q₁Is a carbon atom -NHNH-Q₂Represents an aromatic group or a heterocyclic group bonded to₂Represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a sulfamoyl group. )
15) The development accelerator contains a compound represented by the following general formula (A-2)13)The photothermographic material described in 1.
[0015]
Formula (A-2)
[Formula 4]
[0016]
  In the general formula (A-2), R₁Represents an alkyl group, an acyl group, an acylamino group, a sulfonamide group, an alkoxycarbonyl group, or a carbamoyl group. R₂Represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, or a carbonate group. R_Three, R_FourEach represents a group capable of substituting for the benzene ring mentioned in the example of the substituent of formula (A-1). R_ThreeAnd R_FourMay be linked together to form a condensed ring.
161) to an organic polyhalogen compound as an antifoggant15)The photothermographic material according to any one of the above.
17The organic polyhalogen compound is a compound represented by the following general formula (H)16)The photothermographic material described in 1.
  General formula (H)
      Q- (Y) n-C (Z₁) (Z₂) X
  In the formula, Q represents an alkyl group, an aryl group or a heterocyclic group, Y represents a divalent linking group, n represents 0 or 1, Z₁And Z₂Represents a halogen atom, and X represents a hydrogen atom or an electron withdrawing group.
181) The 1-electron oxidant produced by 1-electron oxidation contains a compound capable of emitting one or more electrons.17)The photothermographic material according to any one of the above.
191) to characterized by laser exposure18)The photothermographic material according to any one of the above.
20) The laser is a semiconductor laser19)The photothermographic material described in 1.
21) The semiconductor laser has an emission peak intensity at 350 nm to 440 nm, and 1 mW / mm²It has the above illuminance20)The photothermographic material described in 1.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in detail below.
The photothermographic material of the invention has an image forming layer containing a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent, and a binder on the same surface of a support. If necessary, it may further have a non-photosensitive layer, for example, a surface protective layer or an intermediate layer between the image forming layer and the surface protective layer. The surface protective layer may be a single layer or a plurality of layers of two or more layers. Further, a back layer or a back protective layer may be provided on the opposite surface of the support to the image forming layer.
[0018]
(Description of binder)
In the present invention, a polymer obtained by copolymerizing 10% by mass or more and 70% by mass or less of a monomer represented by the following general formula (M) is used as the binder of the image forming layer.
General formula (M)
CH₂= CR⁰¹-CR⁰²= CH₂
Where R⁰¹And R⁰²Is a group selected from a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, and a cyano group, provided that R⁰¹And R⁰²Are not simultaneously hydrogen atoms.
[0019]
R⁰¹And R⁰²The preferred alkyl group is an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms. As a halogen atom, a fluorine atom, a chlorine atom, and a bromine atom are preferable, and a chlorine atom is more preferable.
R⁰¹And R⁰²Particularly preferably, one is a hydrogen atom and the other is a methyl group or a chlorine atom.
[0020]
Specific examples of the monomer represented by the general formula (M) of the present invention include 2-ethyl-1,3-butadiene, 2-n-propyl-1,3-butadiene, and 2,3-dimethyl-1,3. -Butadiene, 2-methyl-1,3-butadiene, 2-chloro-1,3-butadiene, 1-bromo-1,3-butadiene, 2-fluoro-1,3-butadiene, 2,3-dichloro-1 , 3-butadiene, 2-cyano-1,3-butadiene.
[0021]
The binder of the present invention is a polymer obtained by copolymerizing the monomer represented by the general formula (M), and the copolymerization ratio of the monomer represented by the general formula (M) in the polymer is 10 to 70% by mass. The amount is preferably 15 to 65% by mass, and more preferably 20 to 60% by mass. When the copolymerization ratio of the monomer represented by the general formula (M) is less than 10% by mass, the fusion component of the binder decreases, and the work brittleness deteriorates. On the other hand, when the copolymerization ratio of the monomer represented by the general formula (M) exceeds 70% by mass, the fusion component of the binder increases and the mobility of the binder increases, so that the image storability deteriorates.
[0022]
In the present invention, the other monomer that can be copolymerized with the monomer represented by formula (M) is not particularly limited, and any monomer that can be polymerized by a normal radical polymerization or ionic polymerization method is preferably used. be able to. The monomers that can be preferably used can be selected independently and freely in combination from the monomer groups (a) to (j) shown below.
[0023]
-Monomer group (a)-(j)-
(A) Conjugated dienes: 1,3-butadiene, 1,3-pentadiene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3 -Butadiene, 1-bromo-1,3-butadiene, 1-chloro-1,3-butadiene, 1,1,2-trichloro-1,3-butadiene, cyclopentadiene and the like.
(B) Olefins: ethylene, propylene, vinyl chloride, vinylidene chloride, 6-hydroxy-1-hexene, 4-pentenoic acid, methyl 8-nonenoate, vinylsulfonic acid, trimethylvinylsilane, trimethoxyvinylsilane, 1,4- Divinylcyclohexane, 1,2,5-trivinylcyclohexane, etc.
(C) α, β-unsaturated carboxylic acid and salts thereof: acrylic acid, methacrylic acid, itaconic acid, maleic acid, sodium acrylate, ammonium methacrylate, potassium itaconate and the like.
[0024]
(D) α, β-unsaturated carboxylic acid esters: alkyl acrylate (eg, methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, etc.), substituted alkyl acrylate (eg, 2-chloro Ethyl acrylate, benzyl acrylate, 2-cyanoethyl acrylate, etc.), alkyl methacrylate (eg, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, etc.), substituted alkyl methacrylate (eg, 2-hydroxyethyl methacrylate, glycidyl methacrylate) Glycerin monomethacrylate, 2-acetoxyethyl methacrylate, tetrahydrofurfurylme Chryrate, 2-methoxyethyl methacrylate, polypropylene glycol monomethacrylate (polyoxypropylene added mole number = 2 to 100), 3-N, N-dimethylaminopropyl methacrylate, chloro-3-N, N, N-trimethyl Ammoniopropyl methacrylate, 2-carboxyethyl methacrylate, 3-sulfopropyl methacrylate, 4-oxysulfobutyl methacrylate, 3-trimethoxysilylpropyl methacrylate, allyl methacrylate, 2-isocyanatoethyl methacrylate, etc.), unsaturated dicarboxylic acid derivatives (Eg, monobutyl maleate, dimethyl maleate, monomethyl itaconate, dibutyl itaconate, etc.), polyfunctional esters (eg, ethylene glycol diacrylate) Ethylene glycol dimethacrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, dipentaerythritol pentamethacrylate, pentaerythritol hexaacrylate, 1,2, 4-cyclohexanetetramethacrylate and the like.
[0025]
(E) Amides of β-unsaturated carboxylic acid: for example, acrylamide, methacrylamide, N-methylacrylamide, N, N-dimethylacrylamide, N-methyl-N-hydroxyethylmethacrylamide, N-tertbutylacrylamide, N- tert-octylmethacrylamide, N-cyclohexylacrylamide, N-phenylacrylamide, N- (2-acetoacetoxyethyl) acrylamide, N-acryloylmorpholine, diacetoneacrylamide, itaconic acid diamide, N-methylmaleimide, 2-acrylamido-methyl Propanesulfonic acid, methylenebisacrylamide, dimethacryloylpiperazine, etc.
(F) Unsaturated nitriles: acrylonitrile, methacrylonitrile and the like.
(G) Styrene and its derivatives: styrene, vinyl toluene, p-tertbutyl styrene, vinyl benzoic acid, methyl vinyl benzoate, α-methyl styrene, p-chloromethyl styrene, vinyl naphthalene, p-hydroxymethyl styrene, p- Styrene sulfonic acid sodium salt, p-styrene sulfinic acid potassium salt, p-aminomethylstyrene, 1,4-divinylbenzene and the like.
(H) Vinyl ethers: methyl vinyl ether, butyl vinyl ether, methoxyethyl vinyl ether and the like.
(I) Vinyl esters: vinyl acetate, vinyl propionate, vinyl benzoate, vinyl salicylate, vinyl chloroacetate, and the like.
(J) Other polymerizable monomers: N-vinylimidazole, 4-vinylpyridine, N-vinylpyrrolidone, 2-vinyloxazoline, 2-isopropenyloxazoline, divinylsulfone, and the like.
[0026]
Preferred examples of the polymer obtained by copolymerizing the monomer represented by the general formula (M) of the present invention include a copolymer with styrene (for example, a random copolymer, a block copolymer, etc.), a copolymer with styrene and butadiene. Copolymer (for example, random copolymer, butadiene-isoprene-styrene block copolymer, styrene-butadiene-isoprene-styrene block copolymer, etc.), copolymer with ethylene-propylene, copolymer with acrylonitrile, Copolymers with isobutylene, copolymers with acrylates (for example, acrylates such as ethyl acrylate and butyl acrylate), and copolymers with acrylates and acrylonitrile (acrylates) Can be the same as described above), and among these, Copolymer of styrene are most preferred.
[0027]
  The polymer of the present invention is copolymerized with a monomer having an acid group in these compositions.To do.As the acid group, carboxylic acid, sulfonic acid, and phosphoric acid are preferable. The copolymerization ratio of the acid group is 1 to 20% by massAnd preferably1 to 10% by mass.
  Specific examples of the monomer having an acid group include acrylic acid, methacrylic acid, itaconic acid, p-styrenesulfonic acid sodium salt, isopropylenesulfonic acid, and phosphorylethyl methacrylate.
[0028]
In the binder of the present invention, any polymer may be used in combination with the copolymer polymer with the monomer represented by the general formula (M). Polymers that can be used in combination are transparent or translucent and generally colorless, natural resins, polymers and copolymers, synthetic resins, polymers and copolymers, and other media forming films such as gelatins, rubbers, (Vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride) ), Poly (methacrylic acid) s, styrene-maleic anhydride copolymers, styrene-acrylonitrile copolymers, styrene-butadiene copolymers, poly (vinyl acetal) s (for example, poly (vinyl formal)) And poly (vinyl butyral)), poly ( Stealth), poly (urethane), phenoxy resin, poly (vinylidene chloride), poly (epoxide), poly (carbonate), poly (vinyl acetate), poly (olefin), cellulose ester, poly There are (amides). The binder may be coated from water or an organic solvent or emulsion.
[0029]
The binder of the present invention preferably has a glass transition temperature (Tg) in the range of −30 ° C. to 70 ° C., more preferably in the range of −10 ° C. to 50 ° C., more preferably in view of processing brittleness and image storage stability. It is in the range of 0 ° C to 40 ° C. Two or more kinds of polymers can be blended and used as the binder. In this case, it is preferable that the weighted average Tg is within the above range in consideration of the composition. In the case of phase separation or having a core-shell structure, the Tg of each phase is preferably within the above range.
[0030]
This glass transition temperature (Tg) can be calculated by the following formula.
1 / Tg = Σ (Xi / Tgi)
Here, it is assumed that n monomer components from i = 1 to n are copolymerized in the polymer. Xi is the weight fraction of the i-th monomer (ΣXi = 1), and Tgi is the glass transition temperature (absolute temperature) of the homopolymer of the i-th monomer. However, Σ is the sum from i = 1 to n. The homopolymer glass transition temperature (Tgi) of each monomer was the value of Polymer Handbook (3rd Edition) (by J. Brandrup, E.H. Immergut (Wiley-Interscience, 1989)).
[0031]
The polymer used for the binder of the present invention can be easily obtained by a solution polymerization method, suspension polymerization method, emulsion polymerization method, dispersion polymerization method, anionic polymerization method, cationic polymerization, etc., but the emulsion polymerization method obtained as a latex Is most preferred. In the emulsion polymerization method, for example, water or a mixed solvent of water and an organic solvent miscible with water (for example, methanol, ethanol, acetone, etc.) is used as a dispersion medium, and the monomer is 5 to 150% by mass with respect to the dispersion medium. Using the mixture and the total amount of monomers, an emulsifier and a polymerization initiator are used, and polymerization is carried out with stirring at about 30 to 100 ° C., preferably 60 to 90 ° C. for 3 to 24 hours. Various conditions such as the dispersion medium, the monomer concentration, the initiator amount, the emulsifier amount, the dispersant amount, the reaction temperature, and the monomer addition method are appropriately set in consideration of the type of monomer used. Moreover, it is preferable to use a dispersing agent as needed.
[0032]
The emulsion polymerization method can be generally performed according to the following literature. “Synthetic Resin Emulsions (Edited by Taira Okuda, Hiroshi Inagaki, Published by Polymer Publishing Company (1978))”, “Application of Synthetic Latex (Takaaki Sugimura, Akio Kataoka, Junichi Suzuki, Keiji Kasahara, Published by Polymer Publishing Company (1993)) ) ”,“ Synthetic Latex Chemistry (Muroichi Muroi, published by Kobunshi Shuppankai (1970)) ”. In the emulsion polymerization method for synthesizing the polymer latex of the present invention, a batch polymerization method, a monomer (continuous / divided) addition method, an emulsion addition method, a seed polymerization method, and the like can be selected. A combination method, a monomer (continuous / divided) addition method, and an emulsion addition method are preferred.
[0033]
The polymerization initiator only needs to have radical generating ability, such as inorganic peroxides such as persulfate and hydrogen peroxide, peroxides described in Nippon Oil & Fats Co., Ltd. organic peroxide catalog, and Wako Pure Chemical Industries, Ltd. The azo compounds described in the azo polymerization initiator catalog can be used. Among these, water-soluble peroxides such as persulfate and water-soluble azo compounds described in the Wako Pure Chemical Industries, Ltd. Azo Polymerization Initiator Catalog are preferable. Ammonium persulfate, sodium persulfate, potassium persulfate, azobis ( 2-methylpropionamidine) hydrochloride, azobis (2-methyl-N- (2-hydroxyethyl) propionamide), azobiscyanovaleric acid is more preferable, and in particular, peroxidation such as ammonium persulfate, sodium persulfate, potassium persulfate and the like. The product is preferable from the viewpoint of image preservability, solubility, and cost.
[0034]
As the addition amount of the polymerization initiator, the polymerization initiator is preferably 0.3% by mass to 2.0% by mass, and 0.4% by mass to 1.75% by mass with respect to the total amount of monomers. Is more preferable, and 0.5% by mass to 1.5% by mass is particularly preferable. When the amount of the polymerization initiator is less than 0.3% by mass, the image storability is lowered, and when it exceeds 2.0%, the latex tends to aggregate and the coatability is lowered.
[0035]
As the polymerization emulsifier, any of an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant can be used, but the anionic surfactant has dispersibility and image storability. From the viewpoint, it is preferable to use a sulfonic acid type anionic surfactant because polymerization stability can be ensured in a small amount and resistance to hydrolysis, and a long-chain alkyldiphenyl ether disulfone represented by Perex SS-H (Kao Co., Ltd.) Acid salts are more preferable, and a low electrolyte type such as Pionine A-43-S (Takemoto Yushi Co., Ltd.) is particularly preferable.
[0036]
As the polymerization emulsifier, a sulfonic acid type anionic surfactant is preferably used in an amount of 0.1% by mass to 10.0% by mass with respect to the total amount of monomers, and 0.2% by mass to 7.5% by mass is used. It is more preferable that 0.3% by mass to 5.0% by mass is used. If the polymerization emulsifier is less than 0.1% by mass, stability during emulsion polymerization cannot be ensured, and if it exceeds 10.0%, the image storage stability decreases.
[0037]
In the synthesis of the polymer latex used in the present invention, it is preferable to use a chelating agent. A chelating agent is a compound capable of coordinating (chelating) multivalent ions such as metal ions such as iron ions and alkaline earth metal ions such as calcium ions. Japanese Patent Publication No. 6-8956, US Pat. JP-A-73645, JP-A-4-127145, JP-A-4-47073, JP-A-4-305572, JP-A-6-11805, JP-A-5-1773312, JP-A-5-66527, JP-A-5- 158195, JP-A-6-118580, JP-A-6-110168, JP-A-6-161054, JP-A-6-175299, JP-A-6-214352, JP-A-7-114161, JP-A-7-114154 JP, 7-120894, JP 7-199433, JP 7-306504, JP 9-43792, JP 8-314090, JP 10-182571, JP 10-182570. The compounds described in JP-A-11-190892 can be used.
[0038]
Examples of the chelating agent include inorganic chelate compounds (sodium tripolyphosphate, sodium hexametaphosphate, sodium tetrapolyphosphate, etc.), aminopolycarboxylic acid chelate compounds (nitrilotritriacetic acid, ethylenediaminetetraacetic acid, etc.), organic phosphonic acid chelate compounds ( Research Disclosure 18170, JP-A-52-102726, 53-42730, 56-97347, 54-121127, 55-4024, 55-4025, 55-29883, 55 -126241, 55-65955, 55-65956, 57-17943, 54-61125, West German Patent 1045373, etc.), polyphenol chelating agents, polyamine chelating compounds, etc. Preferably A minopolycarboxylic acid derivative is particularly preferred.
[0039]
Preferable examples of the aminopolycarboxylic acid derivatives include the compounds listed in the appendix of “EDTA (-Complexane Chemistry)” (Nanedo, 1977), and some of the carboxyl groups of these compounds are sodium or potassium. Alkali metal salts and ammonium salts such as may be substituted. Particularly preferred aminocarboxylic acid derivatives include iminodiacetic acid, N-methyliminodiacetic acid, N- (2-aminoethyl) iminodiacetic acid, N- (carbamoylmethyl) iminodiacetic acid, nitrilotriacetic acid, ethylenediamine-N, N '-Diacetic acid, ethylenediamine-N, N'-di-α-propionic acid, ethylenediamine-N, N'-di-β-propionic acid, N, N'-ethylene-bis (α-o-hydroxyphenyl) glycine N, N′-di (2-hydroxybenzyl) ethylenediamine-N, N′-diacetic acid, ethylenediamine-N, N′-diacetic acid-N, N′-diacethydroxamic acid, N-hydroxyethylethylenediamine-N , N ', N'-triacetic acid, ethylenediamine-N, N, N', N'-tetraacetic acid, 1,2-propylenediamine-N, N, N ', N'-tetraacetic acid, d, l-2 , 3-Diaminobutane-N, N, N ′, N′-tetraacetic acid, meso-2,3-diamy Butane-N, N, N ′, N′-tetraacetic acid, 1-phenylethylenediamine-N, N, N ′, N′-tetraacetic acid, d, l-1,2-diphenylethylenediamine-N, N, N ′ , N′-tetraacetic acid, 1,4-diaminobutane-N, N, N ′, N′-tetraacetic acid, trans-cyclobutane-1,2-diamine-N, N, N ′, N′-tetraacetic acid, trans-cyclopentane-1,2-diamine-N, N, N ′, N′-tetraacetic acid, trans-cyclohexane-1,2-diamine-N, N, N ′, N′-tetraacetic acid, cis-cyclohexane -1,2-diamine-N, N, N ′, N′-tetraacetic acid, cyclohexane-1,3-diamine-N, N, N ′, N′-tetraacetic acid, cyclohexane-1,4-diamine-N , N, N ', N'-tetraacetic acid, o-phenylenediamine-N, N, N', N'-tetraacetic acid, cis-1,4-diaminobutene-N, N, N ', N'-tetra Acetic acid, trans-1,4-diaminobutene-N, N, N ′, N′-tetraacetic acid, α, α′-diamino-o-xylene-N, N, N ′, N′-tetraacetic acid, -Hydroxy-1,3-propanediamine-N, N, N ', N'-tetraacetic acid, 2,2'-oxy-bis (ethyliminodiacetic acid), 2,2'-ethylenedioxy-bis (ethyliminobis) Acetic acid), ethylenediamine-N, N′-diacetic acid-N, N′-di-α-propionic acid, ethylenediamine-N, N′-diacetic acid-N, N′-di-β-propionic acid, ethylenediamine-N , N, N ', N'-tetrapropionic acid, diethylenetriamine-N, N, N', N '', N ''-pentaacetic acid, triethylenetetramine-N, N, N ', N' ', N' '', N '' '-hexaacetic acid, 1,2,3-triaminopropane-N, N, N', N '', N '' ', N' ''-hexaacetic acid, and these A compound in which a part of the carboxyl group of the compound is substituted with an alkali metal salt such as sodium or potassium or an ammonium salt can also be mentioned.
[0040]
The addition amount of the chelating agent is preferably 0.01% by mass to 0.4% by mass, more preferably 0.02% by mass to 0.3% by mass with respect to the total amount of monomers. It is especially preferable that it is 03 mass%-0.15 mass%. When the amount of the chelating agent is less than 0.01% by mass, capture of metal ions mixed in the production process of the polymer latex becomes insufficient, stability against aggregation of the latex is lowered, and applicability is deteriorated. On the other hand, if it exceeds 0.4%, the viscosity of the latex increases and the coatability is lowered.
[0041]
A chain transfer agent is preferably used for the synthesis of the polymer latex used in the present invention. As the chain transfer agent, those described in Polymer Handbook, 3rd edition, (Wiley-Interscience, 1989) are preferable. Sulfur compounds are more preferred because they have high chain transfer ability and can be used in small amounts. Hydrophobic mercaptan-based chain transfer agents such as tert-dodecyl mercaptan and n-dodecyl mercaptan are particularly preferred.
[0042]
The amount of the chain transfer agent is preferably 0.2% by mass to 2.0% by mass, more preferably 0.3% by mass to 1.8% by mass, and 0.4% by mass to 1.6% by mass with respect to the total amount of monomers. Mass% is particularly preferred. When the amount of the chain transfer agent is less than 0.2% by mass, the processing brittleness is lowered, and when it exceeds 2.0% by mass, the image storage stability is deteriorated.
[0043]
In emulsion polymerization, in addition to the above compounds, electrolytes, stabilizers, thickeners, antifoaming agents, antioxidants, vulcanizing agents, antifreezing agents, gelling agents, vulcanization accelerators, etc. are described in synthetic rubber handbooks, etc. These additives may be used.
[0044]
(Specific examples of polymer)
Specific examples of the polymer used in the present invention include exemplified compounds (P-1) to (P-29), but the present invention is not limited to these specific examples. X, y, z, and z ′ in the chemical formula indicate a mass ratio of the polymer composition, and the total sum of x, y, z, and z ′ is 100%. Tg represents the glass transition temperature of the dry film obtained from the polymer.
[0045]
[Chemical formula 5]
[0046]
[Chemical 6]
[0047]
[Chemical 7]
[0048]
[Chemical 8]
[0049]
[Chemical 9]
[0050]
Embedded image
[0051]
Embedded image
[0052]
Hereinafter, although the synthesis example of the polymer used for this invention is shown, it is not necessarily limited to the synthesis method shown here. Other exemplified compounds can be synthesized by the same synthesis method.
[0053]
(Synthesis Example 1-Synthesis of Exemplified Compound P-1)
Add 1500 g of distilled water to the polymerization kettle of the gas monomer reactor (Pressure Glass Industry Co., Ltd. TAS-2J type), heat at 90 ° C. for 3 hours, and passivate to the stainless steel surface of the polymerization kettle and members of the stainless steel stirring device A film is formed. In the polymerization kettle subjected to this treatment, 584.86 g of distilled water bubbled with nitrogen gas for 1 hour, 9.45 g of a surfactant (Pionin A-43-S (manufactured by Takemoto Yushi Co., Ltd.)), 1 mol / liter NaOH 20.25 g, ethylenediaminetetraacetic acid tetrasodium 0.216 g, styrene 332.1 g, isoprene 191.7 g, acrylic acid 16.2 g, tert-dodecyl mercaptan 4.32 g, and the reaction vessel was sealed and stirred at 225 rpm. The mixture was stirred and heated to an internal temperature of 60 ° C. A solution prepared by dissolving 2.7 g of ammonium persulfate in 50 ml of water was added thereto, and the mixture was stirred as it was for 7 hours. The temperature was further raised to 90 ° C. and the mixture was stirred for 3 hours. After the reaction was completed, the internal temperature was lowered to room temperature, and the obtained polymer was filtered with a filter cloth (mesh: 225). 1145 g (45% by mass solid content, 112 nm particle size) was obtained.
[0054]
(Synthesis Example 2-Synthesis of Exemplified Compound P-2)
In a gas monomer reaction apparatus (TAS-2J type manufactured by Pressure Glass Industrial Co., Ltd.), a passive film was formed in the same manner as in Synthesis Example 1 above, and 350.92 g of distilled water in which nitrogen gas was bubbled for 1 hour, a surfactant (Pionine) A-43-S (manufactured by Takemoto Yushi Co., Ltd.)) 3.78 g, 20.25 g of 1 mol / liter NaOH, 0.216 g of ethylenediaminetetraacetic acid tetrasodium salt, 34.02 g of styrene, 18.36 g of isoprene, acrylic acid 1.62 g and 2.16 g of tert-dodecyl mercaptan were added, the reaction vessel was sealed and stirred at a stirring speed of 225 rpm, and the temperature was raised to an internal temperature of 65 ° C. A solution prepared by dissolving 1.35 g of ammonium persulfate in 50 ml of water was added thereto and stirred as it was for 2 hours. Separately, 233.94 g of distilled water, 5.67 g of surfactant (Pionin A-43-S (manufactured by Takemoto Yushi Co., Ltd.)), 306.18 g of styrene, 165.24 g of isoprene, 14.58 g of acrylic acid, tert-dodecyl 2.16 g of mercaptan and 1.35 g of ammonium persulfate were added and stirred to prepare an emulsion, which was added to the reaction vessel over 8 hours. After completion of the addition, the mixture was further stirred for 2 hours. The temperature was further raised to 90 ° C. and stirred for 3 hours. After the reaction was completed, the internal temperature was lowered to room temperature, and the resulting polymer was filtered with a filter cloth (mesh: 225). (Solid content 45% by mass, particle size 121 nm).
[0055]
(Synthesis Example 3-Synthesis of Exemplified Compound P-4)
In a gas monomer reactor (TAS-2J type manufactured by Pressure Glass Co., Ltd.), a passive film was formed in the same manner as in Synthesis Example 1 above, and 578.11 g of distilled water in which nitrogen gas was bubbled for 1 hour, a surfactant (Perex) SS-H (manufactured by Kao Corporation) 16.2 g, 20.25 g of 1 mol / liter NaOH, ethylenediaminetetraacetic acid tetrasodium salt 0.216 g, styrene 321.3 g, isoprene 202.5 g, acrylic acid 16.2 g Then, 4.32 g of tert-dodecyl mercaptan was added, the reaction vessel was sealed, stirred at a stirring speed of 225 rpm, and the temperature was raised to 60 ° C. A solution prepared by dissolving 2.7 g of ammonium persulfate in 25 ml of water was added thereto and stirred as it was for 5 hours. Further, a solution obtained by dissolving 1.35 g of ammonium persulfate in 25 ml of water was added, the temperature was raised to 90 ° C., and the mixture was stirred for 3 hours. After completion of the reaction, the internal temperature was lowered to room temperature, and then the obtained polymer was filtered with a filter cloth (mesh: 225), and 1139 g of Exemplified Compound P-4 (solid content 45% by mass, particle size 105 nm) Obtained.
[0056]
In the polymer latex used in the present invention, an aqueous solvent can be used as a solvent in the coating solution, but a water-miscible organic solvent may be used in combination.
Examples of the water-miscible organic solvent include alcohols such as methyl alcohol, ethyl alcohol and propyl alcohol, cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve, ethyl acetate and dimethylformamide. The amount of these organic solvents added is preferably 50% or less, more preferably 30% or less of the solvent.
[0057]
The polymer latex of the present invention preferably has a polymer concentration of 10 to 70% by mass, more preferably 20 to 60% by mass, and particularly preferably 30 to 55% by mass with respect to the latex liquid.
[0058]
The binder polymer of the present invention preferably has an equilibrium water content of 2% by mass or less at 25 ° C. and 60% RH. More preferably, the equilibrium water content is 0.01% by mass or more and 1.5% by mass or less, and further preferably 0.02% by mass or more and 1.0% by mass or less.
[0059]
“Equilibrium moisture content at 25 ° C. and 60% RH” means the weight W1 of the polymer in the humidity-controlled equilibrium under the atmosphere of 25 ° C. and 60% RH and the weight W0 of the polymer in the absolutely dry state at 25 ° C. Can be expressed as:
Equilibrium moisture content at 25 ℃ 60% RH = [(W1-W0) / W0] x 100 (mass%)
[0060]
For the definition and measurement method of the moisture content, for example, Polymer Engineering Course 14, Polymer Material Testing Method (Edited by Polymer Society, Jinshokan) can be referred to.
[0061]
In the present invention, a polymer dispersible in an aqueous solvent is particularly preferred. Examples of the dispersed state may be either latex in which fine particles of a water-insoluble hydrophobic polymer are dispersed or polymer molecules dispersed in a molecular state or a micelle form. preferable. The average particle size of the dispersed particles is 1 to 50000 nm, preferably 5 to 1000 nm, more preferably 10 to 500 nm, and still more preferably 50 to 200 nm. The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution. Mixing two or more types having a monodispersed particle size distribution is also a preferable method for controlling the physical properties of the coating solution.
[0062]
If necessary, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose may be added to the image forming layer of the present invention. The addition amount of these hydrophilic polymers is preferably 30% by mass or less, more preferably 20% by mass or less, based on the total binder of the image forming layer.
[0063]
The image forming layer of the present invention is preferably formed using a polymer latex. The amount of the binder in the image forming layer is such that the weight ratio of the total binder / organic silver salt is 1/110 to 10, more preferably 1/3 to 5/1, still more preferably 1/1 to 3/1. Range.
[0064]
The total binder / photosensitive silver halide weight ratio of the image forming layer is 400 to 5, more preferably 200 to 10.
[0065]
The total binder amount of the image forming layer of the present invention is preferably 0.2 to 30 g / m.², More preferably 1-15 g / m²More preferably 2-10 g / m²Range. The image forming layer of the present invention may contain a crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like.
[0066]
(Description of organic silver salt)
1) Composition
Organic silver salts that can be used in the present invention are relatively stable to light, but when heated to 80 ° C. or higher in the presence of exposed photosensitive silver halide and reducing agent. It is a silver salt that functions as a silver ion supplier and forms a silver image. The organic silver salt may be any organic substance that can supply silver ions that can be reduced by a reducing agent. Regarding such non-photosensitive organic silver salt, paragraph numbers 0048 to 0049 of JP-A No. 10-62899, page 18 line 24 to page 19 line 37 of European Patent Publication No. 080864A1, European Patent Publication No. 0962812A1, JP-A-11-349591, JP-A-2000-7683, JP-A-2000-72711, and the like. Silver salts of organic acids, particularly silver salts of long-chain aliphatic carboxylic acids (having 10 to 30, preferably 15 to 28 carbon atoms) are preferred. Preferable examples of the fatty acid silver salt include silver lignocerate, silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver erucate and the like. Including a mixture of In the present invention, among these fatty acid silvers, the silver behenate content is preferably 30 mol% to 100 mol%, more preferably 40 mol% to 100 mol%, still more preferably 85 mol% to 100 mol%. The following fatty acid silver is preferably used. Furthermore, it is preferable to use fatty acid silver having a silver erucate content of 2 mol% or less, more preferably 1 mol% or less, and still more preferably 0.1 mol% or less.
[0067]
Moreover, it is preferable that silver stearate content rate is 1 mol% or less. By setting the silver stearate content to 1 mol% or less, a silver salt of an organic acid having a low Dmin, high sensitivity and excellent image storage stability can be obtained. As said silver stearate content rate, 0.5 mol% or less is preferable and it is especially preferable not to contain substantially.
[0068]
Furthermore, when silver arachidate is included as the silver salt of the organic acid, the silver arachidate content is 6 mol% or less to obtain a low Dmin and an organic acid silver salt excellent in image storability. It is preferable at a point and it is still more preferable that it is 3 mol% or less.
[0069]
2) Shape
The shape of the organic silver salt that can be used in the present invention is not particularly limited, and may be any of a needle shape, a rod shape, a flat plate shape, and a flake shape.
In the present invention, scaly organic silver salts are preferred. Also, short needle-shaped, rectangular parallelepiped, cubic or potato-shaped amorphous particles having a major axis / uniaxial length ratio of 5 or less are preferably used. These organic silver particles have a feature that there is less fog at the time of thermal development than long needle-like particles having a ratio of the major axis to the uniaxial length of 5 or more. In particular, particles having a major axis / uniaxial ratio of 3 or less are preferable because the mechanical stability of the coating film is improved. In the present specification, the scaly organic silver salt is defined as follows. The organic acid silver salt was observed with an electron microscope, the shape of the organic acid silver salt particle was approximated to a rectangular parallelepiped, and the sides of the rectangular parallelepiped were designated a, b, and c from the shortest side (c was the same as b). Then, the shorter numerical values a and b are calculated, and x is obtained as follows.
x = b / a
[0070]
In this way, x is obtained for about 200 particles, and when the average value x (average) is obtained, particles satisfying the relationship of x (average) ≧ 1.5 are defined as flakes. Preferably, 30 ≧ x (average) ≧ 1.5, more preferably 15 ≧ x (average) ≧ 1.5. Incidentally, the needle shape is 1 ≦ x (average) <1.5.
[0071]
In the flake shaped particle, a can be regarded as a thickness of a tabular particle having a main plane with b and c as sides. The average of a is preferably 0.01 μm or more and 0.3 μm or less, and more preferably 0.1 μm or more and 0.23 μm or less. The average c / b is preferably 1 or more and 9 or less, more preferably 1 or more and 6 or less, still more preferably 1 or more and 4 or less, and most preferably 1 or more and 3 or less.
[0072]
By setting the equivalent sphere diameter to 0.05 μm or more and 1 μm or less, aggregation is hardly caused in the photosensitive material, and image storability is improved. The sphere equivalent diameter is preferably 0.1 μm or more and 1 μm or less. In the present invention, the method for measuring the equivalent sphere diameter is obtained by directly photographing a sample using an electron microscope and then image-processing the negative.
In the flake shaped particles, the spherical equivalent diameter / a of the particles is defined as the aspect ratio. The aspect ratio of the flake shaped particles is preferably 1.1 or more and 30 or less, more preferably 1.1 or more and 15 or less, from the viewpoint of preventing aggregation in the photosensitive material and improving the image storage stability. .
[0073]
The particle size distribution of the organic silver salt is preferably monodispersed. Monodispersion is preferably 100% or less, more preferably 80% or less, and even more preferably 50% of the value obtained by dividing the standard deviation of the lengths of the short and long axes by the short and long axes, respectively. It is as follows. The method for measuring the shape of the organic silver salt can be determined from a transmission electron microscope image of the organic silver salt dispersion. As another method for measuring monodispersity, there is a method of obtaining the standard deviation of the volume weighted average diameter of the organic silver salt, and the percentage (variation coefficient) of the value divided by the volume weighted average diameter is preferably 100% or less, more Preferably it is 80% or less, more preferably 50% or less. As a measuring method, for example, it is obtained from the particle size (volume weighted average diameter) obtained by irradiating an organic silver salt dispersed in a liquid with laser light and obtaining an autocorrelation function with respect to temporal change of fluctuation of the scattered light. Can do.
[0074]
3) Preparation
Known methods and the like can be applied to the production and dispersion method of the organic acid silver used in the present invention. For example, the above-mentioned JP-A-10-62899, European Patent Publication No. 0803633A1, European Patent Publication No. 0962812A1, JP-A-11-349591, JP-A-2000-7683, JP-A-2000-72711, JP-A-2001-163889, 2001-163890, 2001-163827, 2001-33907, 2001-188313, 2001-83652, 2002-6442, 2002-49117, 2002-31870, 2002-107868 You can refer to the issue.
[0075]
In addition, when the photosensitive silver salt is allowed to coexist at the time of dispersion of the organic silver salt, the fog is increased and the sensitivity is remarkably lowered. Therefore, it is more preferable that the photosensitive silver salt is not substantially contained at the time of dispersion. In the present invention, the amount of the photosensitive silver salt in the aqueous dispersion to be dispersed is preferably 1 mol% or less, more preferably 0.1 mol% or less, based on 1 mol of the organic acid silver salt in the liquid. More preferably, no active addition of photosensitive silver salt is performed.
[0076]
In the present invention, it is possible to produce a photosensitive material by mixing an organic silver salt aqueous dispersion and a photosensitive silver salt aqueous dispersion, but the mixing ratio of the organic silver salt and the photosensitive silver salt can be selected according to the purpose. The ratio of the photosensitive silver salt to the organic silver salt is preferably in the range of 1 to 30 mol%, more preferably 2 to 20 mol%, particularly preferably 3 to 15 mol%. Mixing two or more organic silver salt aqueous dispersions and two or more photosensitive silver salt aqueous dispersions when mixing is a method preferably used for adjusting photographic characteristics.
[0077]
4) Addition amount
The organic silver salt of the present invention can be used in a desired amount, but the total coated silver amount including silver halide is 0.1 to 5.0 g / m.²Is more preferable, more preferably 0.3 to 3.0 g / m²More preferably, 0.5 to 2.0 g / m²It is. In particular, in order to improve image storage stability, the total silver coating amount is 1.8 g / m²Or less, more preferably 1.6 g / m²The following is preferable. If the preferred reducing agent of the present invention is used, it is possible to obtain a sufficient image density even with such a low silver amount.
[0078]
(Description of reducing agent)
The photothermographic material of the present invention preferably contains a heat developer which is a reducing agent for the organic silver salt. The reducing agent for the organic silver salt may be any substance (preferably an organic substance) that reduces silver ions to metallic silver. Examples of such a reducing agent are described in JP-A No. 11-65021, paragraphs 0043 to 0045, and European Patent Publication No. 080364A1, page 7, line 34 to page 18, line 12.
In the present invention, the reducing agent is preferably a so-called hindered phenol-based reducing agent or bisphenol-based reducing agent having a substituent at the ortho position of the phenolic hydroxyl group, and more preferably a compound represented by the following general formula (R).
Formula (R)
[0079]
Embedded image
[0080]
(In the general formula (R), R¹¹And R¹¹Each independently represents an alkyl group having 1 to 20 carbon atoms. R¹²And R¹²Each independently represents a hydrogen atom or a substituent that can be substituted on the benzene ring. L is a -S- group or -CHR¹³-Represents a group. R¹³Represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. X¹And X¹Each independently represents a hydrogen atom or a group capable of substituting for a benzene ring. )
[0081]
The general formula (R) will be described in detail.
1) R¹¹And R¹¹'
R¹¹And R¹¹Each independently represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and the substituent of the alkyl group is not particularly limited, but is preferably an aryl group, a hydroxy group, an alkoxy group, an aryloxy group. Group, alkylthio group, arylthio group, acylamino group, sulfonamido group, sulfonyl group, phosphoryl group, acyl group, carbamoyl group, ester group, ureido group, urethane group, halogen atom and the like.
[0082]
2) R¹²And R¹²', X¹And X¹'
R¹²And R¹²'Are each independently a hydrogen atom or a substituent capable of substituting for a benzene ring;¹And X¹Each 'also independently represents a hydrogen atom or a group that can be substituted on the benzene ring. Preferred examples of each group that can be substituted on the benzene ring include an alkyl group, an aryl group, a halogen atom, an alkoxy group, and an acylamino group.
[0083]
3) L
L is a -S- group or -CHR.¹³-Represents a group. R¹³Represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and the alkyl group may have a substituent. R¹³Specific examples of the unsubstituted alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a heptyl group, an undecyl group, an isopropyl group, a 1-ethylpentyl group, and a 2,4,4-trimethylpentyl group. . Examples of substituents for alkyl groups are R¹¹In the same manner as the above substituent, a halogen atom, an alkoxy group, an alkylthio group, an aryloxy group, an arylthio group, an acylamino group, a sulfonamide group, a sulfonyl group, a phosphoryl group, an oxycarbonyl group, a carbamoyl group, a sulfamoyl group and the like can be mentioned.
[0084]
4) Preferred substituents
R¹¹And R¹¹'Is preferably a secondary or tertiary alkyl group having 3 to 15 carbon atoms, specifically, isopropyl group, isobutyl group, t-butyl group, t-amyl group, t-octyl group, cyclohexyl group, cyclopentyl. Group, 1-methylcyclohexyl group, 1-methylcyclopropyl group and the like. R¹¹And R¹¹'Is more preferably a tertiary alkyl group having 4 to 12 carbon atoms, among which a t-butyl group, a t-amyl group, and a 1-methylcyclohexyl group are more preferable, and a t-butyl group is most preferable.
[0085]
R¹²And R¹²'Is preferably an alkyl group having 1 to 20 carbon atoms, specifically, methyl group, ethyl group, propyl group, butyl group, isopropyl group, t-butyl group, t-amyl group, cyclohexyl group, 1-methyl group. Examples include cyclohexyl group, benzyl group, methoxymethyl group, methoxyethyl group and the like. More preferred are methyl group, ethyl group, propyl group, isopropyl group and t-butyl group.
X¹And X¹'Is preferably a hydrogen atom, a halogen atom or an alkyl group, more preferably a hydrogen atom.
[0086]
L is preferably -CHR¹³-Group.
R¹³Is preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, and the alkyl group is preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, or a 2,4,4-trimethylpentyl group. R¹³Particularly preferred is a hydrogen atom, a methyl group, an ethyl group, a propyl group or an isopropyl group.
[0087]
R¹³R is a hydrogen atom, R¹²And R¹²'Is preferably an alkyl group having 2 to 5 carbon atoms, more preferably an ethyl group or a propyl group, and most preferably an ethyl group.
R¹³Is a primary or secondary alkyl group having 1 to 8 carbon atoms, R¹²And R¹²'Is preferably a methyl group. R¹³The primary or secondary alkyl group having 1 to 8 carbon atoms is preferably a methyl group, an ethyl group, a propyl group or an isopropyl group, more preferably a methyl group, an ethyl group or a propyl group.
R¹¹, R¹¹', R¹²And R¹²When both are methyl groups, R¹³Is preferably a secondary alkyl group. In this case R¹³As the secondary alkyl group, isopropyl group, isobutyl group, and 1-ethylpentyl group are preferable, and isopropyl group is more preferable.
The reducing agent is R¹¹, R¹¹', R¹², R¹²'And R¹³Depending on the combination, the heat developability, developed silver color tone and the like are different. Since these can be adjusted by combining two or more reducing agents, it is preferable to use a combination of two or more depending on the purpose.
[0088]
Although the specific example of the reducing agent of this invention including the compound represented by general formula (R) of this invention below is shown, this invention is not limited to these.
[0089]
Embedded image
[0090]
Examples of preferable reducing agents of the present invention other than the above are compounds described in JP-A Nos. 2001-188314, 2001-209145, 2001-350235, and 2002-156727.
In the present invention, the reducing agent is added in an amount of 0.1 to 3.0 g / m.²And more preferably 0.2 to 1.5 g / m.²And more preferably 0.3 to 1.0 g / m²It is. It is preferably contained in an amount of 5 to 50% by mole, more preferably 8 to 30% by mole, and further preferably 10 to 20% by mole based on 1 mole of silver on the surface having the image forming layer. The reducing agent is preferably contained in the image forming layer.
[0091]
The reducing agent may be contained in the coating solution by any method such as a solution form, an emulsified dispersion form, or a solid fine particle dispersion form, and may be contained in the photosensitive material.
Well-known emulsifying dispersion methods include dissolving oil using an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, or an auxiliary solvent such as ethyl acetate or cyclohexanone, and mechanically dispersing the emulsified dispersion. The method of producing is mentioned.
[0092]
Further, as the solid fine particle dispersion method, a reducing agent powder is dispersed in an appropriate solvent such as water by a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill, or an ultrasonic wave to create a solid dispersion. A method is mentioned. In this case, a protective colloid (for example, polyvinyl alcohol) or a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. Good. In the mills, beads such as zirconia are usually used as a dispersion medium, and Zr and the like eluted from these beads may be mixed in the dispersion. Although it depends on the dispersion conditions, it is usually in the range of 1 ppm to 1000 ppm. If the content of Zr in the light-sensitive material is 0.5 mg or less per gram of silver, there is no practical problem.
The aqueous dispersion preferably contains a preservative (for example, benzoisothiazolinone sodium salt).
Particularly preferred is a solid particle dispersion method of a reducing agent, and it is preferable to add fine particles having an average particle size of 0.01 μm to 10 μm, preferably 0.05 μm to 5 μm, more preferably 0.1 μm to 2 μm. In the present application, it is preferable to use other solid dispersions dispersed in a particle size within this range.
[0093]
(Description of development accelerator)
The development accelerator used in the present invention will be described.
The development accelerator used in the present invention is described in hydrazine compounds represented by the general formula (D) described in JP-A-2002-156727 and JP-A-2001-264929. A phenolic or naphtholic compound represented by the general formula (2) is preferred.
[0094]
Particularly preferred development accelerators of the present invention are compounds represented by the following general formulas (A-1) and (A-2).
Formula (A-1)
Q₁-NHNH-Q₂
(Where Q₁Is a carbon atom -NHNH-Q₂Represents an aromatic group or a heterocyclic group bonded to₂Represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a sulfamoyl group. )
[0095]
In general formula (A-1), Q₁The aromatic group or heterocyclic group represented by is preferably a 5- to 7-membered unsaturated ring. Preferred examples include benzene ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, 1,2,4-triazine ring, 1,3,5-triazine ring, pyrrole ring, imidazole ring, pyrazole ring, 1,2 , 3-triazole ring, 1,2,4-triazole ring, tetrazole ring, 1,3,4-thiadiazole ring, 1,2,4-thiadiazole ring, 1,2,5-thiadiazole ring, 1,3,4 -Oxadiazole ring, 1,2,4-oxadiazole ring, 1,2,5-oxadiazole ring, thiazole ring, oxazole ring, isothiazole ring, isoxazole ring, thiophene ring, etc. are preferable, and these Also preferred are fused rings in which the rings are fused together.
[0096]
These rings may have a substituent, and when they have two or more substituents, these substituents may be the same or different. Examples of substituents include halogen atoms, alkyl groups, aryl groups, carbonamido groups, alkylsulfonamido groups, arylsulfonamido groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, carbamoyl groups, sulfamoyl groups, cyano Groups, alkylsulfonyl groups, arylsulfonyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, and acyl groups. When these substituents are substitutable groups, they may further have substituents. Examples of preferred substituents include halogen atoms, alkyl groups, aryl groups, carbonamido groups, alkylsulfonamido groups, aryls. Sulfonamide group, alkoxy group, aryloxy group, alkylthio group, arylthio group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, cyano group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, and acyloxy group Can be mentioned.
[0097]
Q₂Is preferably a carbamoyl group having 1 to 50 carbon atoms, more preferably 6 to 40 carbon atoms, such as unsubstituted carbamoyl, methylcarbamoyl, N-ethylcarbamoyl, N-propylcarbamoyl, N -Sec-butylcarbamoyl, N-octylcarbamoyl, N-cyclohexylcarbamoyl, N-tert-butylcarbamoyl, N-dodecylcarbamoyl, N- (3-dodecyloxypropyl) carbamoyl, N-octadecylcarbamoyl, N- {3- ( 2,4-tert-pentylphenoxy) propyl} carbamoyl, N- (2-hexyldecyl) carbamoyl, N-phenylcarbamoyl, N- (4-dodecyloxyphenyl) carbamoyl, N- (2-chloro-5-dodecyloxy) Carbonyl Eniru) carbamoyl, N- naphthylcarbamoyl, N-3- pyridylcarbamoyl include N- benzylcarbamoyl.
[0098]
Q₂Is preferably an acyl group having 1 to 50 carbon atoms, more preferably 6 to 40 carbon atoms. For example, formyl, acetyl, 2-methylpropanoyl, cyclohexylcarbonyl, octanoyl, 2-hexyl. Examples include decanoyl, dodecanoyl, chloroacetyl, trifluoroacetyl, benzoyl, 4-dodecyloxybenzoyl, and 2-hydroxymethylbenzoyl. The alkoxycarbonyl group represented by Q2 is preferably an alkoxycarbonyl group having 2 to 50 carbon atoms, more preferably 6 to 40 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, isobutyloxycarbonyl, cyclohexyloxycarbonyl, dodecyl. Examples include oxycarbonyl and benzyloxycarbonyl.
[0099]
Q₂Is preferably an aryloxycarbonyl group having 7 to 50 carbon atoms, more preferably 7 to 40 carbon atoms, such as phenoxycarbonyl, 4-octyloxyphenoxycarbonyl, 2-hydroxymethylphenoxy. Examples include carbonyl and 4-dodecyloxyphenoxycarbonyl. The sulfonyl group represented by Q2 is preferably a sulfonyl group having 1 to 50 carbon atoms, more preferably 6 to 40 carbon atoms, such as methylsulfonyl, butylsulfonyl, octylsulfonyl, 2-hexadecylsulfonyl, 3-dodecyl. Examples include oxypropylsulfonyl, 2-octyloxy-5-tert-octylphenylsulfonyl, and 4-dodecyloxyphenylsulfonyl.
[0100]
Q₂Is preferably a sulfamoyl group having 0 to 50 carbon atoms, more preferably 6 to 40 carbon atoms, such as an unsubstituted sulfamoyl group, an N-ethylsulfamoyl group, or N- (2-ethylhexyl). Sulfamoyl, N-decylsulfamoyl, N-hexadecylsulfamoyl, N- {3- (2-ethylhexyloxy) propyl} sulfamoyl, N- (2-chloro-5-dodecyloxycarbonylphenyl) sulfamoyl, N- (2-tetradecyloxyphenyl) sulfamoyl. Q₂In the group represented by₁May have the groups mentioned as examples of the substituents of the 5- to 7-membered unsaturated ring represented by the formula (1), and when they have two or more substituents, these substituents are the same. Or different.
[0101]
Next, a preferable range of the compound represented by formula (A-1) is described. Q₁Is preferably a 5- to 6-membered unsaturated ring, such as a benzene ring, pyrimidine ring, 1,2,3-triazole ring, 1,2,4-triazole ring, tetrazole ring, 1,3,4-thiadiazole ring, 1 , 2,4-thiadiazole ring, 1,3,4-oxadiazole ring, 1,2,4-oxadiazole ring, thiazole ring, oxazole ring, isothiazole ring, isoxazole ring, and these rings are benzene More preferred is a ring fused to a ring or an unsaturated heterocycle. Q₂Is preferably a carbamoyl group, particularly preferably a carbamoyl group having a hydrogen atom on a nitrogen atom.
[0102]
Formula (A-2)
[0103]
Embedded image
[0104]
In the general formula (A-2), R₁Represents an alkyl group, an acyl group, an acylamino group, a sulfonamide group, an alkoxycarbonyl group, or a carbamoyl group. R₂Represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, or a carbonate group. R_Three, R_FourEach represents a group capable of substituting for the benzene ring mentioned in the example of the substituent of formula (A-1). R_ThreeAnd R_FourMay be linked together to form a condensed ring.
R₁Is preferably an alkyl group having 1 to 20 carbon atoms (eg, methyl group, ethyl group, isopropyl group, butyl group, tert-octyl group, cyclohexyl group, etc.), acylamino group (eg, acetylamino group, benzoylamino group, methylureido). Groups, 4-cyanophenylureido groups, etc.), carbamoyl groups (n-butylcarbamoyl group, N, N-diethylcarbamoyl group, phenylcarbamoyl group, 2-chlorophenylcarbamoyl group, 2,4-dichlorophenylcarbamoyl group, etc.) and acylamino groups (Including a ureido group and a urethane group) is more preferable. R2 is preferably a halogen atom (more preferably a chlorine atom or a bromine atom), an alkoxy group (for example, methoxy group, butoxy group, n-hexyloxy group, n-decyloxy group, cyclohexyloxy group, benzyloxy group, etc.) A group (phenoxy group, naphthoxy group, etc.).
R_ThreeIs preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 20 carbon atoms, and most preferably a halogen atom. R_FourIs preferably a hydrogen atom, an alkyl group or an acylamino group, more preferably an alkyl group or an acylamino group. Examples of these preferred substituents are R₁It is the same. R_FourR is an acylamino group_FourIs R_ThreeIt is also preferred to form a carbostyryl ring by linking with.
[0105]
In the general formula (A-2), R_ThreeAnd R_FourAre connected to each other to form a condensed ring, the naphthalene ring is particularly preferable as the condensed ring. The same substituent as the example of a substituent quoted by general formula (A-1) may couple | bond with the naphthalene ring. When general formula (A-2) is a naphtholic compound, R₁Is preferably a carbamoyl group. Of these, a benzoyl group is particularly preferable. R₂Is preferably an alkoxy group or an aryloxy group, particularly preferably an alkoxy group.
[0106]
Hereinafter, preferred specific examples of the development accelerator of the present invention will be given. The present invention is not limited to these.
[0107]
Embedded image
[0108]
These development accelerators are used in the range of 0.1 to 20 mol% with respect to the reducing agent, preferably in the range of 0.5 to 10 mol%, more preferably in the range of 1 to 5 mol%. The introduction method to the light-sensitive material includes the same method as the reducing agent, but it is particularly preferable to add as a solid dispersion or an emulsified dispersion. When added as an emulsified dispersion, it is added as an emulsified dispersion dispersed using a high-boiling solvent and a low-boiling auxiliary solvent that are solid at room temperature, or as a so-called oilless emulsified dispersion that does not use a high-boiling solvent. It is preferable to add.
[0109]
Examples of the development accelerator of the present invention include other sulfonamidophenol compounds represented by the general formula (A) described in JP-A-2000-267222 and JP-A-2000-330234, and the like. Hindered phenol compounds represented by general formula (II) described in 2001-92075, general formula (I) described in JP-A-10-62895 and JP-A-11-15116, JP Hydrazine compounds represented by general formula (D) of 2002-156727 and general formula (1) described in Japanese Patent Application No. 2001-074278, and those described in Japanese Patent Application Laid-Open No. 2001-264929 A phenolic or naphtholic compound represented by the formula (2) is preferably used.
[0110]
(Description of hydrogen bonding compound)
When the reducing agent in the present invention has an aromatic hydroxyl group (—OH) or an amino group (—NHR, R is a hydrogen atom or an alkyl group), particularly in the case of the aforementioned bisphenols, these groups and hydrogen bonds It is preferable to use together a non-reducing compound having a group capable of forming.
Examples of the group that forms a hydrogen bond with a hydroxyl group or an amino group include a phosphoryl group, a sulfoxide group, a sulfonyl group, a carbonyl group, an amide group, an ester group, a urethane group, a ureido group, a tertiary amino group, and a nitrogen-containing aromatic group. Can be mentioned. Among them, preferred are a phosphoryl group, a sulfoxide group, an amide group (however, it does not have a> N—H group and is blocked like> N—Ra (Ra is a substituent other than H)), a urethane group. (However, it has no> N—H group and is blocked like> N—Ra (Ra is a substituent other than H)), a ureido group (however, it has no> N—H group,> N-Ra (Ra is a substituent other than H).)
In the present invention, a particularly preferred hydrogen bonding compound is a compound represented by the following general formula (D).
Formula (D)
[0111]
Embedded image
[0112]
R in general formula (D)^{twenty one}Or R^{twenty three}Each independently represents an alkyl group, an aryl group, an alkoxy group, an aryloxy group, an amino group or a heterocyclic group, and these groups may be unsubstituted or may have a substituent.
R^{twenty one}Or R^{twenty three}In the case where has a substituent, the substituent is a halogen atom, alkyl group, aryl group, alkoxy group, amino group, acyl group, acylamino group, alkylthio group, arylthio group, sulfonamido group, acyloxy group, oxycarbonyl group, carbamoyl Group, sulfamoyl group, sulfonyl group, phosphoryl group and the like. Preferred as substituents are alkyl groups or aryl groups such as methyl group, ethyl group, isopropyl group, t-butyl group, t-octyl group, phenyl group, 4-alkoxyphenyl group, 4-acyloxyphenyl group and the like can be mentioned.
R^{twenty one}Or R^{twenty three}Specific examples of the alkyl group include methyl group, ethyl group, butyl group, octyl group, dodecyl group, isopropyl group, t-butyl group, t-amyl group, t-octyl group, cyclohexyl group, and 1-methylcyclohexyl group. Benzyl group, phenethyl group, 2-phenoxypropyl group, and the like.
Examples of the aryl group include phenyl group, cresyl group, xylyl group, naphthyl group, 4-t-butylphenyl group, 4-t-octylphenyl group, 4-anisidyl group, and 3,5-dichlorophenyl group.
Alkoxy groups include methoxy, ethoxy, butoxy, octyloxy, 2-ethylhexyloxy, 3,5,5-trimethylhexyloxy, dodecyloxy, cyclohexyloxy, 4-methylcyclohexyloxy, benzyl An oxy group etc. are mentioned.
Examples of the aryloxy group include a phenoxy group, a cresyloxy group, an isopropylphenoxy group, a 4-t-butylphenoxy group, a naphthoxy group, and a biphenyloxy group.
Examples of the amino group include a dimethylamino group, a diethylamino group, a dibutylamino group, a dioctylamino group, an N-methyl-N-hexylamino group, a dicyclohexylamino group, a diphenylamino group, and an N-methyl-N-phenylamino group. .
[0113]
R^{twenty one}Or R^{twenty three}Are preferably an alkyl group, an aryl group, an alkoxy group, or an aryloxy group. In terms of the effect of the present invention, R^{twenty one}Or R^{twenty three}Of these, at least one is preferably an alkyl group or an aryl group, and more preferably two or more are an alkyl group or an aryl group. In addition, R can be obtained at low cost.^{twenty one}Or R^{twenty three}Are preferably the same group.
Specific examples of the hydrogen bonding compound including the compound of the general formula (D) in the present invention are shown below, but the present invention is not limited thereto.
[0114]
Embedded image
[0115]
Specific examples of the hydrogen bonding compound include those described in European Patent No. 1096310, Japanese Patent Application Laid-Open No. 2002-156727, and Japanese Patent Application No. 2001-124796 in addition to the above.
The compound of the general formula (D) of the present invention can be used in a light-sensitive material by being incorporated in a coating solution in the form of a solution, an emulsified dispersion, or a solid dispersion fine particle dispersion in the same manner as the reducing agent. It is preferable to use it as a product. The compound of the present invention forms a hydrogen-bonding complex with a compound having a phenolic hydroxyl group or an amino group in a solution state, and depending on the combination of the reducing agent and the compound of the general formula (D) of the present invention, It can be isolated in the crystalline state.
The use of the crystal powder isolated in this way as a solid dispersed fine particle dispersion is particularly preferable for obtaining stable performance. Further, a method in which the reducing agent and the compound of the general formula (D) of the present invention are mixed as a powder and complexed at the time of dispersion with a sand grinder mill or the like using an appropriate dispersant can be preferably used.
The compound of the general formula (D) of the present invention is preferably used in the range of 1 to 200 mol%, more preferably in the range of 10 to 150 mol%, still more preferably 20 to 100 mol, based on the reducing agent. % Range.
[0116]
(Description of silver halide)
  1) Halogen composition
  The photosensitive silver halide used in the present invention has a silver iodide content of80It is important that the composition is as high as mol% or more and 100 mol% or less. The rest is not particularly limited and can be selected from silver chloride, silver bromide, or organic silver salts such as silver thiocyanate and silver phosphate. Silver bromide and silver chloride are particularly preferred. By using such a silver halide having a high silver iodide content, it is possible to design a preferable photothermographic material in which image storage stability after development processing, in particular, an increase in fog due to light irradiation is remarkably small.
[0117]
  In addition, silver iodide content90From the viewpoint of image storability with respect to light irradiation after the treatment, it is extremely preferable that the amount is from mol% to 100 mol%.
[0118]
The distribution of the halogen composition in the grains may be uniform, the halogen composition may be changed stepwise, or may be continuously changed. Further, silver halide grains having a core / shell structure can also be preferably used. A preferable structure is a 2- to 5-fold structure, and more preferably 2- to 4-fold core / shell particles can be used. A core high silver iodide structure having a high silver iodide content in the core part or a shell high silver iodide structure having a high silver iodide content in the shell part can also be preferably used. Further, a technique of localizing silver chloride or silver bromide as an epitaxial portion on the surface of the grain can be preferably used.
[0119]
2) Particle size
The grain size is particularly important for high silver iodide silver halides used in the present invention. Larger silver halide sizes increase the amount of silver halide coating required to achieve the required maximum density. The present inventor found that the silver halide composition having a high silver iodide content preferably used in the present invention, when the coating amount is large, the development is remarkably suppressed and the sensitivity is lowered, and the density stability with respect to the development time deteriorates. It has been found that the maximum density cannot be obtained in a predetermined development time when the particle size is not less than a certain value. On the other hand, it has been found that if the amount added is limited, the silver iodide has sufficient developability.
[0120]
In this way, when using high silver iodide, the size of the silver halide grains is sufficiently larger than that of conventional silver bromide and silver iodide containing low iodine to achieve a sufficient maximum optical density. It needs to be small. The preferred silver halide grain size is 5 nm or more and 70 nm or less, and more preferably 5 nm or more and 55 nm or less. Especially preferably, it is 10 nm or more and 45 nm or less. The term “particle size” as used herein means an average diameter when converted into a circular image having the same area as the projected area observed with an electron microscope.
[0121]
3) Particle formation method
Methods for forming photosensitive silver halide are well known in the art, for example, the methods described in Research Disclosure June 1978, No. 17029, and US Pat. No. 3,700,458 can be used, Specifically, a method is used in which a photosensitive silver halide is prepared by adding a silver supply compound and a halogen supply compound to gelatin or another polymer solution, and then mixed with an organic silver salt. In addition, the method described in paragraph Nos. 0217 to 0224 of JP-A-11-119374, the method described in JP-A-11-352627, and Japanese Patent Application No. 2000-42336 are also preferable.
[0122]
4) Particle shape
Examples of the shape of the silver halide grains include cubic grains, octahedral grains, tetrahedral grains, dodecahedron grains, tabular grains, spherical grains, rod-shaped grains, and potato-like grains. In particular, dodecahedral grains, tetrahedral grains, and tabular grains are preferable. Although the silver halide having a high silver iodide content composition of the present invention can take a complicated form, a preferable form is shown in, for example, p164-Fig1 of RLJENKINS etal. J of Phot. Sci. Vol. 28 (1980). Examples include bonded particles as shown. Tabular grains as shown in Fig. 1 are also preferably used. Grains with rounded corners of silver halide grains can also be preferably used. The surface index (Miller index) of the outer surface of the photosensitive silver halide grains is not particularly limited, but the proportion of the [100] surface that has high spectral sensitization efficiency when adsorbed by the spectral sensitizing dye is high. preferable. The ratio is preferably 50% or more, more preferably 65% or more, and still more preferably 80% or more. The ratio of the Miller index [100] plane is calculated by T. Tani; J. Imaging Sci., 29, 165 (1985), which uses the adsorption dependence of [111] plane and [100] plane in the adsorption of sensitizing dyes. It can be determined by the method described.
[0123]
5) Heavy metal
The photosensitive silver halide grain of the present invention can contain a metal or metal complex of Group 8 to Group 10 of the Periodic Table (showing Groups 1 to 18). As the central metal of the group 8 to group 10 metal or metal complex of the periodic table, rhodium, ruthenium and iridium are preferable. One kind of these metal complexes may be used, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is 1 x 10 per mole of silver.^-9From mole to 1 × 10^-3A molar range is preferred. These heavy metals and metal complexes and methods for adding them are described in JP-A-7-225449, JP-A-11-65021, paragraphs 0018 to 0024, and JP-A-11-119374, paragraphs 0227 to 0240.
[0124]
In the present invention, silver halide grains in which a hexacyano metal complex is present on the outermost surface of the grains are preferred. As hexacyano metal complexes, [Fe (CN)₆]^Four-, [Fe (CN)₆]^3-, [Ru (CN)₆]^Four-, [Os (CN)₆]^Four-, [Co (CN)₆]^3-, [Rh (CN)₆]^3-, [Ir (CN)₆]^3-, [Cr (CN)₆]^3-, [Re (CN)₆]^3-Etc. In the present invention, a hexacyano Fe complex is preferred.
[0125]
The hexacyano metal complex is present in the form of ions in aqueous solution, so the counter cation is not important, but it is easy to mix with water and is suitable for precipitation of silver halide emulsions. Sodium ion, potassium ion, rubidium It is preferable to use alkali metal ions such as ions, cesium ions, and lithium ions, ammonium ions, and alkylammonium ions (for example, tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, and tetra (n-butyl) ammonium ion).
[0126]
In addition to water, the hexacyano metal complex is miscible with a mixed solvent or gelatin with an appropriate organic solvent miscible with water (for example, alcohols, ethers, glycols, ketones, esters, amides, etc.). Can be added.
[0127]
The amount of hexacyano metal complex added is 1 × 10 5 per mole of silver.^-Five1 x 10 moles or more^-2Or less, more preferably 1 × 10^-Four1 x 10 moles or more^-3It is below the mole.
[0128]
In order for the hexacyano metal complex to be present on the outermost surface of the silver halide grain, the chalcogen sensitization of sulfur sensitization, selenium sensitization and tellurium sensitization is completed after the addition of the aqueous silver nitrate solution used for grain formation. It is added directly before the completion of the preparation step before the chemical sensitization step for performing noble metal sensitization such as sensitization and gold sensitization, during the washing step, during the dispersion step, or before the chemical sensitization step. In order to prevent the silver halide fine grains from growing, it is preferable to add the hexacyano metal complex immediately after the grain formation, and it is preferable to add it before the completion of the preparation step.
[0129]
The addition of the hexacyano metal complex may be started after adding 96% by mass of the total amount of silver nitrate to be added to form grains, more preferably starting after adding 98% by mass, The addition of 99% by mass is particularly preferable.
When these hexacyanometal complexes are added after the addition of the aqueous silver nitrate solution just before the completion of grain formation, they can be adsorbed on the outermost surface of the silver halide grains, and most of them form slightly soluble salts with silver ions on the grain surface. To do. Since this silver salt of hexacyanoiron (II) is a less soluble salt than AgI, it is possible to prevent re-dissolution by fine particles and to produce silver halide fine particles having a small particle size. .
[0130]
Further, metal atoms that can be contained in the silver halide grains used in the present invention (for example, [Fe (CN)₆]^Four-), Desalting methods and chemical sensitization methods for silver halide emulsions, paragraph numbers 0046 to 0050 of JP-A-11-84574, paragraph numbers 0025 to 0031 of JP-A-11-65021, paragraph number 0242 of JP-A-11-119374 ~ 0250.
[0131]
6) Gelatin
Various gelatins can be used as the gelatin contained in the photosensitive silver halide emulsion used in the present invention. In order to maintain a good dispersion state of the photosensitive silver halide emulsion in the organic silver salt-containing coating solution, it is preferable to use a low molecular weight gelatin having a molecular weight of 500 to 60,000. These low molecular weight gelatins may be used at the time of particle formation or dispersion after desalting, but are preferably used at the time of dispersion after desalting.
[0132]
7) Chemical sensitization
The photosensitive silver halide used in the present invention may be non-chemically sensitized, but is preferably chemically sensitized by at least one of a chalcogen sensitizing method, a gold sensitizing method, and a reduction sensitizing method. Examples of the chalcogen sensitizing method include a sulfur sensitizing method, a selenium sensitizing method, and a tellurium sensitizing method.
[0133]
In sulfur sensitization, unstable sulfur compounds are used. The unstable sulfur compounds described in Grafkides, Chimie et Physique Photographic (published by Paul Momtel, 1987, 5th edition), Research Disclosure 307, 307105, and the like can be used.
Specifically, thiosulfate (for example, hypo), thioureas (for example, diphenylthiourea, triethylthiourea, N-ethyl-N ′-(4-methyl-2-thiazolyl) thiourea, carboxymethyltrimethylthiourea), thioamides (Eg, thioacetamide), rhodanines (eg, diethyl rhodanine, 5-benzylidene-N-ethyl rhodanine), phosphine sulfides (eg, trimethylphosphine sulfide), thiohydantoins, 4-oxo-oxazolidin-2 Known sulfur compounds such as -thiones, disulfides, or polysulfides (for example, dimorpholine disulfide, cystine, hexathiocanthion), polythionate, elemental sulfur, and active gelatin can also be used. Particularly preferred are thiosulfates, thioureas and rhodanines.
[0134]
In selenium sensitization, unstable selenium compounds are used, and Japanese Patent Publication Nos. 43-13489, 44-15748, JP-A-4-25832, JP-A-4-109340, JP-A-4-271341, and JP-A-5-40324. No. 5-11385, Japanese Patent Application No. Hei 4-202415, No. 4-330495, No. 4-333030, No. 5-4203, No. 5-4204, No. 5-106977, No. 5-236538. Selenium compounds described in JP-A-5-241642 and JP-A-5-286916 can be used.
[0135]
Specifically, colloidal metal selenium, selenoureas (eg, N, N-dimethylselenourea, trifluoromethylcarbonyl-trimethylselenourea, acetyl-trimethylselenourea), selenoamides (eg, selenoamide, N, N-diethyl) Phenylselenoamide), phosphine selenides (eg, triphenylphosphine selenide, pentafluorophenyl-triphenylphosphine selenide), selenophosphates (eg, tri-p-tolylselenophosphate, tri-n) -Butylselenophosphate), selenoketones (for example, selenobenzophenone), isoselenocyanates, selenocarboxylic acids, selenoesters, diacyl selenides and the like may be used. Furthermore, non-labile selenium compounds described in JP-B Nos. 46-4553 and 52-34492, such as selenite, selenocyanate, selenazoles, and selenides can also be used. In particular, phosphine selenides, selenoureas and selenocyanates are preferred.
[0136]
In tellurium sensitization, an unstable tellurium compound is used, and JP-A-4-224595, JP-A-4-271341, JP-A-4-3333043, JP-A-5-303157, JP-A-6-27573, JP-A-6-175258, The unstable tellurium described in JP-A-6-180478, JP-A-6-208186, JP-A-6-208184, JP-A-6-317867, JP-A-7-140579, JP-A-7-301879, JP-A-7-301880, etc. A compound can be used.
[0137]
Specifically, phosphine tellurides (for example, butyl-diisopropylphosphine telluride, tributylphosphine telluride, tributoxyphosphine telluride, ethoxydiphenylphosphine telluride), diacyl (di) tellurides ( For example, bis (diphenylcarbamoyl) ditelluride, bis (N-phenyl-N-methylcarbamoyl) ditelluride, bis (N-phenyl-N-methylcarbamoyl) telluride, bis (N-phenyl-N-benzylcarbamoyl) telluride, bis (ethoxycarbonyl) Telluride), telluroureas (for example, N, N′-dimethylethylenetellurourea, N, N′-diphenylethylenetellurourea) telluramides, telluroesters and the like may be used. In particular, diacyl (di) tellurides and phosphine tellurides are preferred, particularly the compounds described in the literature described in paragraph No. 0030 of JP-A-11-65021, the general formula (II) in JP-A-5-313284, Compounds represented by (III) and (IV) are more preferred.
[0138]
Particularly, in the chalcogen sensitization of the present invention, selenium sensitization and tellurium sensitization are preferable, and tellurium sensitization is particularly preferable.
[0139]
In gold sensitization, P.I. Gold sensitizers described by Grafkides, Chimie et Physique Photographic (published by Paul Momtel, 1987, 5th edition), Research Disclosure 307, No. 307105 can be used. Specifically, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide and the like, in addition to these, U.S. Pat. Nos. 2,642,361, 5,049,484, 5,049,485, 5,169,751, Gold compounds described in 5252455, Belgian Patent No. 691857 and the like can also be used. P. Precious metals such as platinum, palladium, iridium, etc. other than gold described in Grafkides, Chimie et Physique Photographic (published by Paul Momtel, 1987, 5th edition), Research Disclosure 307, 307105 are also used. I can do it.
[0140]
Although gold sensitization can be used alone, it is preferably used in combination with the chalcogen sensitization described above. Specifically, gold sulfur sensitization, gold selenium sensitization, gold tellurium sensitization, gold sulfur selenium sensitization, gold sulfur tellurium sensitization, gold selenium tellurium sensitization, and gold sulfur selenium tellurium sensitization.
[0141]
In the present invention, chemical sensitization is possible at any time after particle formation and before coating, and after desalting, (1) before spectral sensitization, (2) simultaneously with spectral sensitization, (3) spectral sensitization After sensitization, there may be (4) just before application.
[0142]
The amount of chalcogen sensitizer used in the present invention varies depending on the silver halide grains used, chemical ripening conditions, etc., but is 10 per mole of silver halide.^-8-10^-1Moles, preferably 10^-7-10^-2Use moles.
Similarly, the amount of the gold sensitizer used in the present invention varies depending on various conditions, but as a guideline, it is 10 per silver halide.^-7Mol-10^-2Mole, more preferably 10^-6Mol ~ 5x10^-3Is a mole. The environmental conditions for chemically sensitizing this emulsion can be selected under any conditions, but the pAg is 8 or less, preferably 7.0 or less to 6.5 or less, particularly 6.0 or less, and the pAg is 1.5 or less. Above, preferably 2.0 or more, particularly preferably 2.5 or more, pH is 3 to 10, preferably 4 to 9, temperature is 20 to 95 ° C., preferably about 25 to 80 ° C. is there.
[0143]
In the present invention, reduction sensitization can be used in combination with chalcogen sensitization or gold sensitization. In particular, it is preferably used in combination with chalcogen sensitization.
As specific compounds for the reduction sensitization, ascorbic acid, thiourea dioxide, and dimethylamine borane are preferable. In addition, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds, etc. It is preferable to use it. The reduction sensitizer may be added at any stage in the photosensitive emulsion production process from crystal growth to the preparation process immediately before coating. Further, reduction sensitization is also preferable by ripening while maintaining the pH of the emulsion at 8 or more or pAg at 4 or less, and reduction sensitization is performed by introducing a single addition portion of silver ions during grain formation. Is also preferable.
The amount of reduction sensitizer added varies depending on various conditions, but as a guideline it is 10 per silver halide.^-7Mol-10^-1Mole, more preferably 10^-6Mol ~ 5x10^-2Is a mole.
[0144]
A thiosulfonic acid compound may be added to the silver halide emulsion used in the present invention by the method described in European Patent Publication No. 293,917.
The photosensitive silver halide grains in the invention are preferably chemically sensitized by at least one of gold sensitization and chalcogen sensitization from the viewpoint of designing a high-sensitivity photothermographic material.
[0145]
The photosensitive silver halide emulsion in the invention preferably contains an FED sensitizer (Fragmentable electron donating sensitizer) as a compound that generates two electrons with one photon. As the FED sensitizer, compounds described in US Pat. Nos. 5,747,235, 5747236, 6054260, 599941, and Japanese Patent Application No. 2001-86161 are preferable. As the step of adding the FED sensitizer, any process of the photosensitive emulsion production process from crystal growth to the preparation process immediately before coating is preferable. The amount added varies depending on various conditions, but as a guideline, it is 10 per silver halide.^-7From mole 10^-1Mole, more preferably 10^-6Mol ~ 5 × 10^-2Is a mole.
[0146]
8) Sensitizing dye
As a sensitizing dye that can be applied to the present invention, it can spectrally sensitize silver halide grains in a desired wavelength region when adsorbed on silver halide grains, and has a spectral sensitivity suitable for the spectral characteristics of the exposure light source. The dye can be advantageously selected. The photothermographic material of the present invention is preferably spectrally sensitized so as to have a spectral sensitivity peak at 600 nm to 900 nm, or 300 nm to 500 nm. As for the sensitizing dye and the addition method, paragraphs 0103 to 0109 of JP-A-11-65021, compounds represented by general formula (II) of JP-A-10-186572, and general formulas (I) of JP-A-11-119374 ) And a dye described in Paragraph No. 0106, U.S. Pat.Nos. 5,510,236 and 3,871,887, Example 5, a dye disclosed in JP-A-2-96131 and JP-A-59-48753, European Patent Publication No. 074364A1, page 19, line 38 to page 20, line 35, Japanese Patent Application No. 2000-86865, Japanese Patent Application No. 2000-102560, Japanese Patent Application No. 2000-205399, and the like. These sensitizing dyes may be used alone or in combination of two or more.
[0147]
The addition amount of the sensitizing dye in the present invention can be set to a desired amount in accordance with the sensitivity and fogging performance, but is 10 per mol of silver halide in the photosensitive layer.^-6~ 1 mol is preferred, more preferably 10^-Four~Ten^-1Is a mole.
[0148]
In the present invention, a supersensitizer can be used to improve spectral sensitization efficiency. Examples of supersensitizers used in the present invention include European Patent Publication No. 587,338, U.S. Pat.Nos. 3,877,943, 4,873,184, JP-A Nos. 5-341432, 11-109547, and 10-111543. And the compounds described.
[0149]
9) A compound in which a one-electron oxidant produced by one-electron oxidation can emit one electron or more.
In the photothermographic material of the invention, it is preferable that the one-electron oxidant produced by one-electron oxidation contains a compound capable of emitting one electron or more.
The compound can be used alone or in combination with the above-described various chemical sensitizers, and can increase the sensitivity of silver halide.
[0150]
The one-electron oxidant produced by one-electron oxidation contained in the photothermographic material of the present invention is a compound selected from the following types 1 to 5 that can emit one or more electrons.
[0151]
(Type 1)
A compound in which a one-electron oxidant produced by one-electron oxidation can further emit two or more electrons with a subsequent bond cleavage reaction.
(Type 2)
The one-electron oxidant produced by one-electron oxidation is a compound capable of releasing another electron with subsequent bond cleavage reaction, and has two or more adsorptive groups to silver halide in the same molecule. Compound.
(Type 3)
A compound capable of emitting one or more electrons after a one-electron oxidant produced by one-electron oxidation undergoes a subsequent bond formation process.
(Type 4)
A compound capable of emitting one or more electrons after a one-electron oxidant produced by one-electron oxidation undergoes a subsequent intramolecular ring-cleaving reaction.
(Type 5)
In the compound represented by XY, X represents a reducing group, Y represents a leaving group, and a one-electron oxidant formed by one-electron oxidation of the reducing group represented by X is followed by XY A compound capable of releasing Y by releasing Y with a bond cleavage reaction and releasing another electron therefrom.
[0152]
Preferred among the compounds of types 1 and 3 to 5 are “compounds having an adsorbing group for silver halide in the molecule” or “partial structure of spectral sensitizing dye in the molecule”. Compound ". More preferred is a “compound having an adsorptive group to silver halide in the molecule”. The compounds of types 1 to 4 are more preferably “compounds having a nitrogen-containing heterocyclic group substituted with two or more mercapto groups as an adsorptive group”.
[0153]
The compounds of types 1 to 5 will be described in detail.
In the type 1 compound, “bond cleavage reaction” specifically means cleavage of bonds between carbon-carbon, carbon-silicon, carbon-hydrogen, carbon-boron, carbon-tin, and carbon-germanium elements, These may be further accompanied by carbon-hydrogen bond cleavage. A type 1 compound is a compound capable of emitting two or more (preferably three or more) electrons for the first time after a one-electron oxidation to form a one-electron oxidant with a bond cleavage reaction.
[0154]
Among the compounds of type 1, preferred compounds are represented by general formula (A), general formula (B), general formula (1), general formula (2) or general formula (3).
[0155]
Formula (A)
Embedded image
[0156]
General formula (B)
Embedded image
[0157]
In general formula (A), RED₁₁Represents a reducing group which can be oxidized by one electron, and L₁₁Represents a leaving group. R₁₁₂Represents a hydrogen atom or a substituent. R₁₁₁Is carbon atom (C) and RED₁₁And a nonmetallic atomic group capable of forming a cyclic structure corresponding to a tetrahydro form, hexahydro form, or octahydro form of a 5-membered or 6-membered aromatic ring (including an aromatic heterocycle).
[0158]
In the general formula (B), RED₁₂Represents a reducing group which can be oxidized by one electron, and L₁₂Represents a leaving group. R₁₂₁And R₁₂₂Each represents a hydrogen atom or a substituent. ED₁₂Represents an electron donating group. R in the general formula (B)₁₂₁And RED₁₂, R₁₂₁And R₁₂₂Or ED₁₂And RED₁₂And may be bonded to each other to form a cyclic structure.
[0159]
These compounds represented by general formula (A) or general formula (B) are represented by RED.₁₁Or RED₁₂After the reducing group represented by₁₁Or L₁₂Is a compound that can release two or more electrons, preferably three or more electrons, by releasing them by bond cleavage reaction.
[0160]
General formula (1), general formula (2), general formula (3)
Embedded image
[0161]
In general formula (1), Z₁Represents an atomic group capable of forming a 6-membered ring with a nitrogen atom and two carbon atoms of a benzene ring, and R₁, R₂, R_N1Each represents a hydrogen atom or a substituent, and X₁Represents a substitutable substituent on the benzene ring, m₁Represents an integer of 0 to 3, L₁Represents a leaving group. ED in general formula (2)_{twenty one}Represents an electron donating group, R₁₁, R₁₂, R_N21, R₁₃, R₁₄Each represents a hydrogen atom or a substituent, and X_{twenty one}Represents a substitutable substituent on the benzene ring, m_{twenty one}Represents an integer of 0 to 3, L_{twenty one}Represents a leaving group. R_N21, R₁₃, R₁₄, X_{twenty one}And ED_{twenty one}May be bonded to each other to form a cyclic structure. In the general formula (3), R₃₂, R₃₃, R₃₁, R_N31, R_a, R_bEach represents a hydrogen atom or a substituent, and L₃₁Represents a leaving group. However, R_N31When represents a group other than an aryl group, R_aAnd R_bCombine with each other to form an aromatic ring.
[0162]
After these compounds are oxidized by one electron,₁, L_{twenty one}Or L₃₁Is a compound that can release two or more electrons, preferably three or more electrons, by releasing them by bond cleavage reaction.
[0163]
Hereinafter, the compound represented by formula (A) will be described in detail below.
In general formula (A), RED₁₁A reducing group that can be oxidized by one electron is represented by R described later.₁₁₁And a divalent group obtained by removing one hydrogen atom at a suitable site for ring formation from the following monovalent group. For example, alkylamino group, arylamino group (anilino group, naphthylamino group etc.), heterocyclic amino group (benzthiazolylamino group, pyrrolylamino group etc.), alkylthio group, arylthio group (phenylthio group etc.), heterocyclic thiol Group, alkoxy group, aryloxy group (phenoxy group etc.), heterocyclic oxy group, aryl group (phenyl group, naphthyl group, anthranyl group etc.), aromatic or non-aromatic heterocyclic group (5-membered to 7-membered) A monocyclic or condensed heterocyclic ring containing at least one heteroatom among nitrogen atom, sulfur atom, oxygen atom and selenium atom. Specific examples thereof include, for example, a tetrahydroquinoline ring, a tetrahydroisoquinoline ring, and a tetrahydroquinoxaline ring. , Tetrahydroquinazoline ring, indoline ring, indole ring, indazole ring, carbazo Ring, phenoxazine ring, phenothiazine ring, benzothiazoline ring, pyrrole ring, imidazole ring, thiazoline ring, piperidine ring, pyrrolidine ring, morpholine ring, benzimidazole ring, benzoimidazoline ring, benzoxazoline ring, methylenedioxyphenyl ring, etc. (Hereinafter referred to as RED for convenience)₁₁Is described as a monovalent radical name). RED₁₁May have a substituent.
[0164]
In the present invention, the substituent means a substituent selected from the following groups unless otherwise specified. Halogen atom, alkyl group (including aralkyl group, cycloalkyl group, active methine group, etc.), alkenyl group, alkynyl group, aryl group, heterocyclic group (regardless of the position of substitution), quaternized nitrogen atom A heterocyclic group (e.g., pyridinio group, imidazolio group, quinolinio group, isoquinolinio group), acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, carboxy group or salt thereof, sulfonylcarbamoyl group, acylcarbamoyl group, sulfa Moylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group, cyano group, carboximidoyl group, thiocarbamoyl group, hydroxy group, alkoxy group (including groups containing ethyleneoxy group or propyleneoxy group unit repeatedly), aryloxy group Heterocycle o Si group, acyloxy group, (alkoxy or aryloxy) carbonyloxy group, carbamoyloxy group, sulfonyloxy group, amino group, (alkyl, aryl, or heterocyclic) amino group, acylamino group, sulfonamide group, ureido group, thioureido Group, imide group, (alkoxy or aryloxy) carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, ammonio group, oxamoylamino group, (alkyl or aryl) sulfonylureido group, acylureido group , Acylsulfamoylamino group, nitro group, mercapto group, (alkyl, aryl, or heterocyclic) thio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or Salts, sulfamoyl group, sulfonylsulfamoyl group or a salt thereof, phosphoric acid amide or a group containing a phosphoric acid ester structure and so forth. These substituents may be further substituted with these substituents.
[0165]
RED₁₁Are preferably an alkylamino group, an arylamino group, a heterocyclic amino group, an aryl group, an aromatic or non-aromatic heterocyclic group, more preferably an arylamino group (particularly an anilino group), an aryl group (particularly a phenyl group). Group). When these have a substituent, the substituent is preferably a halogen atom, an alkyl group, an alkoxy group, a carbamoyl group, a sulfamoyl group, an acylamino group, or a sulfonamide group.
However, RED₁₁When represents an aryl group, the aryl group preferably has at least one “electron-donating group”. Here, the “electron donating group” means a hydroxy group, an alkoxy group, a mercapto group, a sulfonamide group, an acylamino group, an alkylamino group, an arylamino group, a heterocyclic amino group, an active methine group, and a nitrogen atom in the ring. 5-membered, monocyclic or condensed, electron-rich aromatic heterocyclic group (for example, indolyl group, pyrrolyl group, imidazolyl group, benzimidazolyl group, thiazolyl group, benzthiazolyl group, indazolyl group, etc.), nitrogen A non-aromatic nitrogen-containing heterocyclic group (a group that can also be called a cyclic amino group such as a pyrrolidinyl group, an indolinyl group, a piperidinyl group, a piperazinyl group, or a morpholino group) substituted with an atom. Here, the active methine group means a methine group substituted by two “electron-withdrawing groups”, and the “electron-withdrawing group” means an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, It means a carbamoyl group, an alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group, a trifluoromethyl group, a cyano group, a nitro group, or a carbonimidoyl group. Here, the two electron withdrawing groups may be bonded to each other to form a cyclic structure.
[0166]
In general formula (A), L₁₁Is specifically a carboxy group or a salt thereof, a silyl group, a hydrogen atom, a triarylboron anion, a trialkylstannyl group, a trialkylgermyl group, or -CR_C1R_C2R_C3Represents a group. Here, the silyl group specifically represents a trialkylsilyl group, an aryldialkylsilyl group, a triarylsilyl group, or the like, and may have an arbitrary substituent.
[0167]
L₁₁When represents a salt of a carboxy group, examples of counter ions that form salts include alkali metal ions, alkaline earth metal ions, heavy metal ions, ammonium ions, phosphonium ions, and the like, preferably alkali metal ions or ammonium ions. Alkali metal ions (especially Li⁺, Na⁺, K⁺Ion) is most preferred.
[0168]
L₁₁-CR_C1R_C2R_C3When representing a group, here R_C1, R_C2, R_C3Each independently represents a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an alkylthio group, an arylthio group, an alkylamino group, an arylamino group, a heterocyclic amino group, an alkoxy group, an aryloxy group, or a hydroxy group. May be bonded to each other to form a cyclic structure, and may further have an arbitrary substituent. However, R_C1, R_C2, R_C3When one of them represents a hydrogen atom or an alkyl group, the remaining two do not represent a hydrogen atom or an alkyl group. R_C1, R_C2, R_C3Preferably, each independently represents an alkyl group, an aryl group (particularly a phenyl group), an alkylthio group, an arylthio group, an alkylamino group, an arylamino group, a heterocyclic group, an alkoxy group, or a hydroxy group. For example, phenyl group, p-dimethylaminophenyl group, p-methoxyphenyl group, 2,4-dimethoxyphenyl group, p-hydroxyphenyl group, methylthio group, phenylthio group, phenoxy group, methoxy group, ethoxy group, dimethylamino Group, N-methylanilino group, diphenylamino group, morpholino group, thiomorpholino group, hydroxy group and the like. Examples of the case where they are bonded to each other to form a cyclic structure include 1,3-dithiolan-2-yl group, 1,3-dithian-2-yl group, N-methyl-1,3-thiazolidine-2 -Yl group, N-benzyl-benzothiazolidin-2-yl group and the like.
-CR_C1R_C2R_C3The group is R_C1, R_C2, R_C3As a result of each selected within the above-mentioned range, the general formula (A) to L₁₁It is also preferred if it represents the same group as the residue excluding.
[0169]
In general formula (A), L₁₁Is preferably a carboxy group or a salt thereof, and a hydrogen atom. More preferably, it is a carboxy group or a salt thereof.
[0170]
L₁₁When represents a hydrogen atom, the compound represented by the general formula (A) preferably has a base moiety inherent in the molecule. After the compound represented by the general formula (A) is oxidized by the action of this base moiety,₁₁Is deprotonated, and further electrons are emitted therefrom.
[0171]
Here, the base is specifically a conjugate base of an acid having a pKa of about 1 to about 10. For example, nitrogen-containing heterocycles (pyridines, imidazoles, benzimidazoles, thiazoles, etc.), anilines, trialkylamines, amino groups, carbon acids (active methylene anions, etc.), thioacetic acid anions, carboxylates (- COO^-), Sulfate (-SO_Three ^-), Or amine oxide (> N⁺(O^-)-) And the like. Preferably, it is a conjugate base of an acid exhibiting a pKa of about 1 to about 8, more preferably carboxylate, sulfate or amine oxide, particularly preferably carboxylate. When these bases have anions, they may have counter cations, examples of which include alkali metal ions, alkaline earth metal ions, heavy metal ions, ammonium ions, phosphonium ions and the like. These bases are linked to the compound represented by the general formula (A) at an arbitrary position. The position at which these base sites bind is the RED of general formula (A)₁₁, R₁₁₁, R₁₁₂Any of these may be sufficient, and you may connect with the substituent of these groups.
[0172]
R in the general formula (A)₁₁₂Represents a substituent substitutable on a hydrogen atom or a carbon atom. However, R₁₁₂Is L₁₁And does not represent the same group.
R₁₁₂Is preferably a hydrogen atom, an alkyl group, an aryl group (such as a phenyl group), an alkoxy group (such as a methoxy group, an ethoxy group, and a benzyloxy group), a hydroxy group, an alkylthio group (such as a methylthio group and a butylthio group), an amino group, and an alkyl group An amino group, an arylamino group and a heterocyclic amino group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, a hydroxy group, a phenyl group and an alkylamino group.
[0173]
R in the general formula (A)₁₁₁Is a ring structure corresponding to a tetrahydro, hexahydro or octahydro form of a 5-membered or 6-membered aromatic ring (including aromatic heterocycle), where the hydro form is an aromatic A ring structure in which a carbon-carbon double bond (or carbon-nitrogen double bond) in a ring (including an aromatic heterocycle) is partially hydrogenated means a tetrahydro form, and two hexahydro forms The three and octahydro forms mean a structure in which four carbon-carbon double bonds (or carbon-nitrogen double bonds) are hydrogenated. By being hydrogenated, the aromatic ring becomes a partially hydrogenated non-aromatic ring structure.
Specifically, pyrrolidine ring, imidazolidine ring, thiazolidine ring, pyrazolidine ring and oxazolidine ring, piperidine ring, tetrahydropyridine ring, tetrahydropyrimidine ring, piperazine ring, tetralin ring, tetrahydroquinoline ring, tetrahydroisoquinoline ring, tetrahydroquinazoline ring, And tetrahydroquinoxaline ring, tetrahydrocarbazole ring, octahydrophenanthridine ring and the like. These ring structures may have an arbitrary substituent.
[0174]
R₁₁₁More preferably, the cyclic structure formed by pyrrolidine ring, imidazolidine ring, piperidine ring, tetrahydropyridine ring, tetrahydropyrimidine ring, piperazine ring, tetrahydroquinoline ring, tetrahydroisoquinoline ring, tetrahydroquinazoline ring, tetrahydroquinoxaline ring, tetrahydrocarbazole ring Particularly preferred are pyrrolidine ring, piperidine ring, piperazine ring, tetrahydropyridine ring, tetrahydroquinoline ring, tetrahydroisoquinoline ring, tetrahydroquinazoline ring, tetrahydroquinoxaline ring, most preferably pyrrolidine ring, piperidine ring, tetrahydropyridine ring. , Tetrahydroquinoline ring and tetrahydroisoquinoline ring.
[0175]
In general formula (B), RED₁₂, L₁₂Are respectively RED of the general formula (A)₁₁, L₁₁The preferred range is also the same. However, RED₁₂Is a monovalent group except when it forms the following cyclic structure, specifically RED.₁₁And monovalent group names described in the above. R₁₂₁And R₁₂₂Is R in the general formula (A)₁₁₂The preferred range is also the same. ED₁₂Represents an electron donating group. R₁₂₁And RED₁₂, R₁₂₁And R₁₂₂Or ED₁₂And RED₁₂And may be bonded to each other to form a cyclic structure.
[0176]
ED in general formula (B)₁₂The electron donating group represented by RED₁₁Is the same as the electron-donating group described as the substituent for when A represents an aryl group. ED₁₂Preferably a hydroxy group, an alkoxy group, a mercapto group, a sulfonamide group, an alkylamino group, an arylamino group, an active methine group, a 5-membered monocyclic or condensed ring electron containing at least one nitrogen atom in the ring An excess aromatic heterocyclic group, a non-aromatic nitrogen-containing heterocyclic group substituted with a nitrogen atom, and a phenyl group substituted with these electron donating groups, and further a hydroxy group, a mercapto group, a sulfonamide group, an alkylamino group Groups, arylamino groups, active methine groups, non-aromatic nitrogen-containing heterocyclic groups substituted with nitrogen atoms, and phenyl groups substituted with these electron-donating groups (for example, p-hydroxyphenyl groups, p-dialkylaminophenyl groups) , O, p-dialkoxyphenyl group, etc.) are more preferable.
[0177]
R in the general formula (B)₁₂₁And RED₁₂, R₁₂₂And R₁₂₁Or ED₁₂And RED₁₂And may be bonded to each other to form a cyclic structure. The cyclic structure formed here is a non-aromatic carbocyclic or heterocyclic ring, which is a 5-membered to 7-membered monocyclic or condensed ring, and is a substituted or unsubstituted cyclic structure. R₁₂₁And RED₁₂When and form a ring structure, specific examples thereof include R in general formula (A).₁₁₁In addition to those listed as examples of the cyclic structure formed by pyrroline ring, imidazoline ring, thiazoline ring, pyrazoline ring, oxazoline ring, indane ring, morpholine ring, indoline ring, tetrahydro-1,4-oxazine ring, 2, 3-dihydrobenzo-1,4-oxazine ring, tetrahydro-1,4-thiazine ring, 2,3-dihydrobenzo-1,4-thiazine ring, 2,3-dihydrobenzofuran ring, 2,3-dihydrobenzothiophene A ring etc. are mentioned. ED₁₂And RED₁₂And form a ring structure, ED₁₂Preferably represents an amino group, an alkylamino group, or an arylamino group, and specific examples of the ring structure formed include a tetrahydropyrazine ring, a piperazine ring, a tetrahydroquinoxaline ring, and a tetrahydroisoquinoline ring. R₁₂₂And R₁₂₁When and form a ring structure, specific examples thereof include a cyclohexane ring and a cyclopentane ring.
[0178]
Next, general formulas (1) to (3) will be described.
In the general formulas (1) to (3), R₁, R₂, R₁₁, R₁₂, R₃₁Is R in the general formula (A)₁₁₂The preferred range is also the same. L₁, L_{twenty one}, L₃₁Is L in the general formula (A)₁₁Represents the same leaving group as the specific examples given in the description, and preferred ranges thereof are also the same. X₁, X_{twenty one}As the substituent represented by the formula (A),₁₁Is the same as the example of the substituent when has a substituent, and the preferred range is also the same. m₁, M_{twenty one}Is preferably an integer of 0 to 2, more preferably 0 or 1.
[0179]
R_N1, R_N21, R_N31When represents a substituent, the substituent is preferably an alkyl group, an aryl group, or a heterocyclic group, and these may further have an arbitrary substituent. R_N1, R_N21, R_N31Is preferably a hydrogen atom, an alkyl group or an aryl group, more preferably a hydrogen atom or an alkyl group.
[0180]
R₁₃, R₁₄, R₃₃, R_a, R_bWhen represents a substituent, the substituent is preferably an alkyl group, aryl group, acyl group, alkoxycarbonyl group, carbamoyl group, cyano group, alkoxy group, acylamino group, sulfonamido group, ureido group, thioureido group, alkylthio group. An arylthio group, an alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group, and the like.
[0181]
In general formula (1), Z₁The 6-membered ring formed by is a non-aromatic heterocycle condensed with the benzene ring of the general formula (1). Specifically, a tetrahydroquinoline ring, a tetrahydroquinoxaline ring as a ring structure including the condensed benzene ring, A tetrahydroquinazoline ring, preferably a tetrahydroquinoline ring or a tetrahydroquinoxaline ring. These may have a substituent.
[0182]
ED in general formula (2)_{twenty one}Is the ED of the general formula (B)₁₂The preferred range is also the same.
[0183]
In the general formula (2), R_N21, R₁₃, R₁₄, X_{twenty one}And ED_{twenty one}Any two of these may combine with each other to form a cyclic structure. Where R_N21And X_{twenty one}The cyclic structure formed by bonding is preferably a 5- to 7-membered non-aromatic carbocyclic or heterocyclic ring condensed with a benzene ring. Specific examples thereof include a tetrahydroquinoline ring and a tetrahydroquinoxaline. A ring, an indoline ring, a 2,3-dihydro-5,6-benzo-1,4-thiazine ring, and the like. Preferred are a tetrahydroquinoline ring, a tetrahydroquinoxaline ring and an indoline ring.
[0184]
In the general formula (3), R_N31When represents a group other than an aryl group, R_aAnd R_bCombine with each other to form an aromatic ring. Here, the aromatic ring is an aryl group (for example, a phenyl group or a naphthyl group) and an aromatic heterocyclic group (for example, a pyridine ring group, a pyrrole ring group, a quinoline ring group, or an indole ring group), and an aryl group is preferable. The aromatic ring group may have an arbitrary substituent.
In the general formula (3), R_aAnd R_bAre preferably bonded to each other to form an aromatic ring (particularly a phenyl group).
[0185]
In the general formula (3), R₃₂Is preferably a hydrogen atom, an alkyl group, an aryl group, a hydroxy group, an alkoxy group, a mercapto group, an amino group, etc., where R₃₂When R represents a hydroxy group,₃₃The case where represents an “electron-withdrawing group” is also a preferred example. Here, the “electron withdrawing group” is the same as described above, and an acyl group, an alkoxycarbonyl group, a carbamoyl group, and a cyano group are preferable.
[0186]
Next, the type 2 compound will be described.
In the type 2 compound, “bond cleavage reaction” means carbon-carbon, carbon-silicon, carbon-hydrogen, carbon-boron, carbon-tin, carbon-germanium bond cleavage, and carbon-hydrogen. This may be accompanied by cleavage of the bond.
[0187]
The type 2 compound is a compound having two or more (preferably 2 to 6, more preferably 2 to 4) adsorptive groups to silver halide in the molecule. More preferred is a compound having a nitrogen-containing heterocyclic group substituted with two or more mercapto groups as an adsorptive group. The number of adsorptive groups is preferably 2-6, more preferably 2-4. The adsorptive group will be described later.
[0188]
A preferable compound among the compounds of type 2 is represented by the general formula (C).
[0189]
General formula (C)
Embedded image
[0190]
The compound represented by the general formula (C) is RED₂After the reducing group represented by₂It is a compound that can release one more electron with this by leaving the group by bond cleavage reaction.
[0191]
In general formula (C), RED₂Is RED of general formula (B)₁₂Represents the same group, and the preferred range is also the same. L₂Is L in the general formula (A)₁₁Represents the same group as described above, and its preferred range is also the same. L₂When represents a silyl group, the compound is a compound having, as an adsorptive group, a nitrogen-containing heterocyclic group substituted with two or more mercapto groups in the molecule. R_{twenty one}, R_{twenty two}Represents a hydrogen atom or a substituent, and these are R in the general formula (A)₁₁₂The preferred range is also the same. RED₂And R_{twenty one}And may be bonded to each other to form a ring structure.
[0192]
The ring structure formed here is a 5-membered to 7-membered monocyclic or condensed, non-aromatic carbocycle or heterocycle, which may have a substituent. However, the ring structure is not a ring structure corresponding to a tetrahydro, hexahydro or octahydro form of an aromatic ring or an aromatic heterocycle. The ring structure is preferably a ring structure corresponding to a dihydro form of an aromatic ring or an aromatic heterocycle, and specific examples thereof include, for example, a 2-pyrroline ring, a 2-imidazoline ring, a 2-thiazoline ring, 1,2- Dihydropyridine ring, 1,4-dihydropyridine ring, indoline ring, benzimidazoline ring, benzothiazoline ring, benzoxazoline ring, 2,3-dihydrobenzothiophene ring, 2,3-dihydrobenzofuran ring, benzo-α-pyran ring, 1 , 2-dihydroquinoline ring, 1,2-dihydroquinazoline ring, 1,2-dihydroquinoxaline ring and the like, preferably 2-imidazoline ring, 2-thiazoline ring, indoline ring, benzoimidazoline ring, benzothiazoline ring, Benzoxazoline ring, 1,2-dihydropyridine ring, 1,2-dihydroquino Down ring, 1,2-dihydro-quinazoline ring, and the like 1,2-dihydro-quinoxaline ring, indoline ring, benzimidazoline ring, a benzothiazoline ring, 1,2-dihydroquinoline ring is more preferable, indoline ring is particularly preferred.
[0193]
Next, the compound of type 3 will be described.
In the type 3 compound, “bond formation process” means formation of an interatomic bond such as carbon-carbon, carbon-nitrogen, carbon-sulfur, carbon-oxygen and the like.
[0194]
The compound of type 3 is preferably a reactive group site (carbon-carbon double bond site, carbon-carbon triple bond site, fragrance) in which a one-electron oxidant formed by one-electron oxidation coexists in the molecule. And a non-aromatic heterocyclic group part of a benzo-condensed ring) to form a bond and then emit one electron or more electrons.
[0195]
More specifically, a type 3 compound has a one-electron oxidant formed by one-electron oxidation (a cation radical species or a neutral radical species produced by elimination of a proton therefrom) in the same molecule. It reacts with the coexisting reactive group, forms a bond, and generates a radical species having a new ring structure in the molecule. This radical species has a feature that electrons of the second electron are emitted directly or with elimination of protons.
And in some Type 3 compounds, the two-electron oxidant so produced is then subjected to a hydrolysis reaction in some cases, and in some cases tautomerization with direct proton transfer. There is a case in which one or more electrons, usually two or more electrons are emitted from the oxidization reaction. Alternatively, those having the ability to emit one or more electrons, usually two or more electrons, directly from a two-electron oxidant without going through such a tautomerization reaction are also included.
[0196]
The compound of type 3 is preferably represented by the general formula (D).
[0197]
Formula (D)
Embedded image
[0198]
In general formula (D), RED_ThreeRepresents a reducing group which can be oxidized by one electron, Y_ThreeIs RED_ThreeRepresents a reactive group site that reacts after one-electron oxidation, specifically a carbon-carbon double bond site, a carbon-carbon triple bond site, an aromatic group site, or a non-aromatic heterocycle of a benzo-fused ring An organic group containing a ring group site is represented. L_ThreeIs RED_ThreeAnd Y_ThreeRepresents a linking group for linking.
[0199]
RED_ThreeIs RED of general formula (B)₁₂And is preferably an arylamino group, a heterocyclic amino group, an aryloxy group, an arylthio group, an aryl group, an aromatic or non-aromatic heterocyclic group (particularly a nitrogen-containing heterocyclic group is preferred). And more preferably an arylamino group, a heterocyclic amino group, an aryl group, an aromatic or non-aromatic heterocyclic group, and among these heterocyclic groups, a tetrahydroquinoline ring group, a tetrahydroquinoxaline ring group, a tetrahydroquinazoline ring Group, indoline ring group, indole ring group, carbazole ring group, phenoxazine ring group, phenothiazine ring group, benzothiazoline ring group, pyrrole ring group, imidazole ring group, thiazole ring group, benzimidazole ring group, benzimidazoline ring group, Benzothiazoline ring group, 3,4-methylenedioxyphenyl-1-yl group Etc. are preferable.
RED_ThreeParticularly preferred are an arylamino group (particularly anilino group), an aryl group (particularly a phenyl group), and an aromatic or non-aromatic heterocyclic group.
[0200]
Where RED_ThreeWhen represents an aryl group, the aryl group preferably has at least one “electron-donating group”. The “electron donating group” is the same as described above.
[0201]
RED_ThreeWhen represents an aryl group, the substituent of the aryl group is more preferably an alkylamino group, a hydroxy group, an alkoxy group, a mercapto group, a sulfonamide group, an active methine group, a non-aromatic nitrogen-containing heterocycle substituted with a nitrogen atom More preferably an alkylamino group, a hydroxy group, an active methine group, and a non-aromatic nitrogen-containing heterocyclic group substituted with a nitrogen atom, and most preferably an alkylamino group and a non-aromatic group substituted with a nitrogen atom. Nitrogen heterocyclic group.
[0202]
Y_ThreeWhen the organic group containing a carbon-carbon double bond site represented by (for example, vinyl group) has a substituent, the substituent is preferably an alkyl group, a phenyl group, an acyl group, a cyano group, an alkoxycarbonyl group, A carbamoyl group, an electron donating group, and the like. The electron donating group is preferably an alkoxy group, a hydroxy group (which may be protected with a silyl group, such as a trimethylsilyloxy group, a t-butyldimethylsilyloxy group, Phenylsilyloxy group, triethylsilyloxy group, phenyldimethylsilyloxy group, etc.), amino group, alkylamino group, arylamino group, sulfonamide group, active methine group, mercapto group, alkylthio group, and these electron donors It is a phenyl group having a functional group as a substituent.
[0203]
Here, when the organic group containing a carbon-carbon double bond site has a hydroxy group as a substituent, Y_ThreeIs the partial structure on the right:> C₁= C₂(—OH) — is included, but this is tautomerized and the partial structure shown on the right:> C₁HC₂It may be (= O)-. In this case, the C₁It is also preferred that the substituent substituted for carbon is an electron withdrawing group, in which case Y_ThreeHas a partial structure of “active methylene group” or “active methine group”. The electron withdrawing group that can give such a partial structure of the active methylene group or active methine group is the same as that described in the description of the above-mentioned “active methine group”.
[0204]
Y_ThreeWhen the organic group containing a carbon-carbon triple bond site represented by (for example, ethynyl group) has a substituent, examples of the substituent include an alkyl group, a phenyl group, an alkoxycarbonyl group, a carbamoyl group, and an electron donating group. preferable.
[0205]
Y_ThreeRepresents an organic group containing an aromatic group, an aromatic group is preferably an aryl group having an electron donating group as a substituent (particularly a phenyl group is preferred) or an indole ring group, where the electron donating group is Preferred are a hydroxy group (which may be protected with a silyl group), an alkoxy group, an amino group, an alkylamino group, an active methine group, a sulfonamide group and a mercapto group.
[0206]
Y_ThreeRepresents an organic group containing a non-aromatic heterocyclic group portion of a benzo-fused ring, preferably a benzo-fused non-aromatic heterocyclic group that preferably has an aniline structure as a partial structure, for example, an indoline ring group, 1,2,3,4-tetrahydroquinoline ring group, 1,2,3,4-tetrahydroquinoxaline ring group, 4-quinolone ring group and the like can be mentioned.
[0207]
Y_ThreeMore preferred as the reactive group represented by is an organic group containing a carbon-carbon double bond site, an aromatic group site, or a benzo-fused non-aromatic heterocyclic group. More preferred are a carbon-carbon double bond site, a phenyl group having an electron donating group as a substituent, an indole ring group, and a benzo-fused non-aromatic heterocyclic group having an aniline structure as a partial structure. Here, the carbon-carbon double bond site preferably has at least one electron donating group as a substituent.
[0208]
Y_ThreeAs a result of the selection of the reactive group represented by_ThreeThe case where it has the same partial structure as the reducing group represented by general formula (D) is also a preferred example of the compound represented by general formula (D).
[0209]
L_ThreeRED_ThreeAnd Y_ThreeAnd specifically represents a single bond, an alkylene group, an arylene group, a heterocyclic group, -O-, -S-, -NR._N-, -C (= O)-, -SO₂The group which consists of individual group of-, -SO-, -P (= O)-, or a combination of these groups is represented. R here_NRepresents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group. L_ThreeThe linking group represented by may have an arbitrary substituent. L_ThreeThe linking group represented by RED_ThreeAnd Y_ThreeIn any position of the group represented by the formula (1), each of the hydrogen atoms may be linked to replace any one hydrogen atom.
L_ThreePreferred examples of are: a single bond, an alkylene group (particularly a methylene group, an ethylene group, a propylene group), an arylene group (particularly a phenylene group), a —C (═O) — group, an —O— group, an —NH— group, -N (alkyl group)-group, and the bivalent coupling group which consists of a combination of these groups are mentioned.
[0210]
L_ThreeThe group represented by_ThreeCation radical species (X⁺.), Or a radical species (X.) generated from the proton withdrawn therefrom, and Y_ThreeWhen the reactive group represented by the above reacts to form a bond, the atomic group involved in this reaction is L_ThreeIt is preferable that a 3-7 membered cyclic structure including can be formed. For this purpose, radical species (X⁺-Or X-), the reactive group represented by Y, and L are preferably connected by 3 to 7 atomic groups.
[0211]
Next, the type 4 compound will be described.
A compound of type 4 is a compound having a ring structure substituted with a reducing group, and after the reducing group is oxidized by one electron, one or more electrons are emitted along with the ring structure cleavage reaction. Compound. The ring structure cleavage reaction referred to here means one having the following form.
[0212]
Embedded image
[0213]
In the formula, compound a represents a type 4 compound. In compound a, D represents a reducing group, and X and Y represent atoms forming a bond that is cleaved after one-electron oxidation in the ring structure. First, one-electron oxidation of the compound a generates a one-electron oxidant b. From this, the single bond of XX becomes a double bond, and at the same time, the bond of XY is cleaved to produce a ring-opened product c. Alternatively, a radical intermediate d may be generated from the one-electron oxidant b with proton desorption, and a ring opening e may be similarly generated therefrom. The compound of the present invention is characterized in that one or more electrons are subsequently released from the ring-opened product c or e thus produced.
[0214]
The ring structure possessed by the type 4 compound is a 3- to 7-membered carbocyclic or heterocyclic ring, and represents a monocyclic or condensed, saturated or unsaturated non-aromatic ring. A saturated ring structure is preferable, and a 3-membered ring or 4-membered ring is more preferable. Preferred examples of the ring structure include a cyclopropane ring, a cyclobutane ring, an oxirane ring, an oxetane ring, an aziridine ring, an azetidine ring, an episulfide ring, and a thietane ring. More preferred are cyclopropane ring, cyclobutane ring, oxirane ring, oxetane ring and azetidine ring, and particularly preferred are cyclopropane ring, cyclobutane ring and azetidine ring. The ring structure may have an arbitrary substituent.
[0215]
The compound of type 4 is preferably represented by the general formula (E) or (F).
[0216]
General formula (E)
Embedded image
[0217]
Formula (F)
Embedded image
[0218]
RED in general formula (E) and general formula (F)₄₁And RED₄₂Are respectively RED of the general formula (B)₁₂Represents a group having the same meaning, and the preferred range thereof is also the same. R₄₀~ R₄₄And R₄₅~ R₄₉Each represents a hydrogen atom or a substituent. In general formula (F), Z₄₂Is -CR₄₂₀R₄₂₁-, -NR₄₂₃-Represents-or -O-. R here₄₂₀, R₄₂₁Each represents a hydrogen atom or a substituent, and R₄₂₃Represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group.
[0219]
R in general formula (E) and general formula (F)₄₀And R₄₅Preferably represents a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group, more preferably a hydrogen atom, an alkyl group or an aryl group. R₄₁~ R₄₄And R₄₆~ R₄₉And preferably a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an arylthio group, an alkylthio group, an acylamino group, or a sulfonamide group, more preferably a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group. is there.
[0220]
R₄₁~ R₄₄In which at least one of these is a donor group, and R₄₁And R₄₂Or R₄₃And R₄₄Are preferably electron withdrawing groups. More preferably R₄₁~ R₄₄This is a case where at least one of the above is a donor group. More preferably R₄₁~ R₄₄At least one of them is a donor group and R₄₁~ R₄₄In this case, the group that is not a donor group is a hydrogen atom or an alkyl group.
[0221]
The donor group mentioned here is an “electron-donating group” or an aryl group substituted with at least one “electron-donating group”. The donor group is preferably an alkylamino group, an arylamino group, a heterocyclic amino group, a 5-membered monocyclic or condensed ring electron-rich aromatic heterocyclic group containing at least one nitrogen atom in the ring, nitrogen A non-aromatic nitrogen-containing heterocyclic group substituted with an atom or a phenyl group substituted with at least one electron-donating group is used. More preferably, an alkylamino group, an arylamino group, a 5-membered monocyclic or condensed ring-excessive aromatic heterocyclic group containing at least one nitrogen atom in the ring (an indole ring, a pyrrole ring, a carbazole ring, etc.) ), A phenyl group substituted with an electron donating group (such as a phenyl group substituted with three or more alkoxy groups, a phenyl group substituted with a hydroxy group, an alkylamino group, or an arylamino group). Particularly preferably, an arylamino group, a 5-membered monocyclic or condensed ring-containing electron-rich aromatic heterocyclic group (particularly a 3-indolyl group) or an electron-donating group containing at least one nitrogen atom in the ring is substituted. Used phenyl groups (particularly phenyl groups substituted with trialkoxyphenyl groups, alkylamino groups or arylamino groups).
[0222]
Z₄₂Preferably as -CR₄₂₀R₄₂₁-Or -NR₄₂₃-, More preferably -NR₄₂₃-. R₄₂₀, R₄₂₁Is preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, an acylamino group or a sulfoneamino group, more preferably a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group. R₄₂₃Preferably represents a hydrogen atom, an alkyl group, an aryl group or an aromatic heterocyclic group, more preferably a hydrogen atom, an alkyl group or an aryl group.
[0223]
R₄₀~ R₄₉And R₄₂₀, R₄₂₁, R₄₂₃When each of these groups is a substituent, those having a total carbon number of 40 or less are preferable, more preferably a total carbon number of 30 or less, and particularly preferably a total carbon number of 15 or less. These substituents may be bonded to each other or other sites in the molecule (RED₄₁, RED₄₂Or Z₄₂) To form a ring.
[0224]
In the compounds of types 1 to 4 of the present invention, the adsorptive group to silver halide is a group that directly adsorbs to silver halide or a group that promotes adsorption to silver halide. Specifically, mercapto A heterocyclic group containing at least one atom selected from a group (or a salt thereof), a thione group (—C (═S) —), a nitrogen atom, a sulfur atom, a selenium atom and a tellurium atom, a sulfide group, a cationic group, Or an ethynyl group. However, the type 2 compound of the present invention does not contain a sulfide group as an adsorptive group.
[0225]
The mercapto group (or salt thereof) as the adsorptive group means the mercapto group (or salt thereof) itself, and more preferably a heterocyclic group or aryl group substituted with at least one mercapto group (or salt thereof). Or represents an alkyl group. Here, the heterocyclic group is a 5-membered to 7-membered monocyclic or condensed aromatic or non-aromatic heterocyclic group such as an imidazole ring group, a thiazole ring group, an oxazole ring group, or a benzimidazole ring group. , Benzthiazole ring group, benzoxazole ring group, triazole ring group, thiadiazole ring group, oxadiazole ring group, tetrazole ring group, purine ring group, pyridine ring group, quinoline ring group, isoquinoline ring group, pyrimidine ring group, triazine A cyclic group etc. are mentioned. Further, it may be a heterocyclic group containing a quaternized nitrogen atom. In this case, the substituted mercapto group may be dissociated into a meso ion. Examples of such a heterocyclic group include an imidazolium ring group, Examples include a pyrazolium ring group, a thiazolium ring group, a triazolium ring group, a tetrazolium ring group, a thiadiazolium ring group, a pyridinium ring group, a pyrimidinium ring group, and a triazinium ring group. Among them, a triazolium ring group (for example, 1,2,4- Triazolium-3-thiolate ring group) is preferable. Examples of the aryl group include a phenyl group and a naphthyl group. Examples of the alkyl group include linear, branched or cyclic alkyl groups having 1 to 30 carbon atoms. When the mercapto group forms a salt, the counter ion is a cation such as an alkali metal, alkaline earth metal, or heavy metal (Li⁺, Na⁺, K⁺, Mg²⁺, Ag⁺, Zn²⁺Etc.), ammonium ions, quaternized heterocyclic groups containing nitrogen atoms, phosphonium ions and the like.
[0226]
Further, the mercapto group as the adsorptive group may be tautomerized into a thione group, specifically, a thioamide group (here, —C (═S) —NH— group), and the thioamide group. A group having a partial structure of, ie, a chain or cyclic thioamide group, a thioureido group, a thiourethane group, or a dithiocarbamate group. Examples of cyclic groups include thiazolidine-2-thione group, oxazolidine-2-thione group, 2-thiohydantoin group, rhodanine group, isorhodanine group, thiobarbituric acid group, 2-thioxo-oxazolidine-4-one group Is mentioned.
[0227]
The thione group as an adsorptive group cannot be tautomerized to a mercapto group (including a hydrogen atom at the α-position of the thione group), including the case where the mercapto group described above is tautomerized into a thione group. A chain or cyclic thioamide group, thioureido group, thiourethane group, or dithiocarbamate group is also included.
[0228]
A heterocyclic group containing at least one atom selected from a nitrogen atom, a sulfur atom, a selenium atom and a tellurium atom as the adsorptive group is a -NH- group capable of forming imino silver (> NAg) and a partial structure of the heterocyclic ring A nitrogen-containing heterocyclic group, or a “—S—” group, a “—Se—” group, a “—Te—” group or a “═N—” group which can coordinate to a silver ion via a coordination bond. A heterocyclic group having a ring partial structure. Examples of the former include benzotriazole group, triazole group, indazole group, pyrazole group, tetrazole group, benzimidazole group, imidazole group, and purine group, and examples of the latter include thiophene. Group, thiazole group, oxazole group, benzothiazole group, benzoxazole group, thiadiazole group, oxadiazole group, triazine group, selenoazo Group, benzselenoazole group, tellurazole group, benztelluazole group and the like. The former is preferred.
[0229]
The sulfide group as the adsorptive group includes all groups having a partial structure of “—S—”, preferably alkyl (or alkylene) -S-alkyl (or alkylene), aryl (or arylene) -S—. A group having a partial structure of alkyl (or alkylene), aryl (or arylene) -S-aryl (or arylene). Furthermore, these sulfide groups may form a cyclic structure or may be an -S-S- group. Specific examples in the case of forming a cyclic structure include a thiolane ring, a 1,3-dithiolane ring or a 1,2-dithiolane ring, a thiane ring, a dithiane ring, a tetrahydro-1,4-thiazine ring (thiomorpholine ring) and the like. Groups. Particularly preferred as the sulfide group is a group having a partial structure of alkyl (or alkylene) -S-alkyl (or alkylene).
[0230]
The cationic group as the adsorptive group means a group containing a quaternized nitrogen atom, specifically, an ammonio group or a group containing a nitrogen-containing heterocyclic group containing a quaternized nitrogen atom. . However, the cationic group does not become a part of an atomic group forming a dye structure (for example, a cyanine chromophore). Here, the ammonio group is a trialkylammonio group, a dialkylarylammonio group, an alkyldiarylammonio group or the like, and examples thereof include a benzyldimethylammonio group, a trihexylammonio group, and a phenyldiethylammonio group. Examples of the nitrogen-containing heterocyclic group containing a quaternized nitrogen atom include a pyridinio group, a quinolinio group, an isoquinolinio group, an imidazolio group, and the like. A pyridinio group and an imidazolio group are preferable, and a pyridinio group is particularly preferable. These nitrogen-containing heterocyclic groups containing a quaternized nitrogen atom may have an arbitrary substituent, but in the case of a pyridinio group and an imidazolio group, the substituent is preferably an alkyl group, an aryl group, an acylamino group , A chloro atom, an alkoxycarbonyl group, a carbamoyl group and the like. In the case of a pyridinio group, a phenyl group is particularly preferred as a substituent.
[0231]
An ethynyl group as an adsorptive group means a —C≡CH group, and a hydrogen atom may be substituted.
The above adsorptive group may have an arbitrary substituent.
[0232]
Specific examples of the adsorptive group further include those described in pages 4 to 7 of JP-A No. 11-95355.
[0233]
Preferred as the adsorptive group in the present invention is a mercapto-substituted nitrogen-containing heterocyclic group (for example, 2-mercaptothiadiazole group, 3-mercapto-1,2,4-triazole group, 5-mercaptotetrazole group, 2-mercapto-1). , 3,4-oxadiazole group, 2-mercaptobenzoxazole group, 2-mercaptobenzthiazole group, 1,5-dimethyl-1,2,4-triazolium-3-thiolate group), or imino silver (> A nitrogen-containing heterocyclic group (for example, a benzotriazole group, a benzimidazole group, an indazole group, etc.) having a —NH— group that can form NAg) as a partial structure of the heterocyclic ring. Particularly preferred are 5-mercaptotetrazole group, 3-mercapto-1,2,4-triazole group, and benzotriazole group, most preferred are 3-mercapto-1,2,4-triazole group, and 5 -A mercaptotetrazole group.
[0234]
Of the compounds of the present invention, compounds having two or more mercapto groups as partial structures in the molecule are also particularly preferred compounds. Here, the mercapto group (—SH) may be a thione group if it can be tautomerized. Examples of such compounds include the above-described adsorptive groups having a mercapto group or thione group as a partial structure (for example, a ring-forming thioamide group, an alkyl mercapto group, an aryl mercapto group, a heterocyclic mercapto group, etc.) Or an adsorbing group having two or more mercapto groups or thione groups as a partial structure (for example, a dimercapto-substituted nitrogen-containing telocyclic group). You may have one or more.
[0235]
Examples of the adsorptive group having two or more mercapto groups as a partial structure (such as a dimercapto-substituted nitrogen-containing telocyclic group) include 2,4-dimercaptopyrimidine group, 2,4-dimercaptotriazine group, 3,5 -Dimercapto-1,2,4-triazole group, 2,5-dimercapto-1,3-thiazole group, 2,5-dimercapto-1,3-oxazole group, 2,7-dimercapto-5-methyl-s- Triazolo (1,5-A) -pyrimidine, 2,6,8-trimercaptopurine, 6,8-dimercaptopurine, 3,5,7-trimercapto-s-triazolotriazine, 4,6-dimercapto Examples include pyrazolopyrimidine, 2,5-dimercaptoimidazole, 2,4-dimercaptopyrimidine group, 2,4-dimercaptotriazine group, 3,5. Dimercapto-1,2,4-triazole group are particularly preferred.
[0236]
The adsorptive group may be substituted anywhere in the general formulas (A) to (F) and the general formulas (1) to (3), but in the general formulas (A) to (D), RED₁₁, RED₁₂, RED₂, RED_ThreeIn the general formulas (E) and (F), RED₄₁, R₄₁, RED₄₂, R₄₆~ R₄₈In the general formulas (1) to (3), R₁, R₂, R₁₁, R₁₂, R₃₁, L₁, L_{twenty one}, L₃₁It is preferably substituted at any position except for RED, and RED in all of the general formulas (A) to (F)₁₁~ RED₄₂More preferably, it is substituted.
[0237]
The partial structure of the spectral sensitizing dye is a group containing a chromophore of the spectral sensitizing dye, and is a residue obtained by removing any hydrogen atom or substituent from the spectral sensitizing dye compound. The partial structure of the spectral sensitizing dye may be substituted anywhere in the general formulas (A) to (F) and the general formulas (1) to (3), but in the general formulas (A) to (D), RED₁₁, RED₁₂, RED₂, RED_ThreeIn the general formulas (E) and (F), RED₄₁, R₄₁, RED₄₂, R₄₆~ R₄₈In the general formulas (1) to (3), R₁, R₂, R₁₁, R₁₂, R₃₁, L₁, L_{twenty one}, L₃₁It is preferably substituted at any position except for RED, and RED in all of the general formulas (A) to (F)₁₁~ RED₄₂More preferably, it is substituted. Preferred spectral sensitizing dyes are spectral sensitizing dyes typically used in color sensitization techniques such as cyanine dyes, complex cyanine dyes, merocyanine dyes, complex merocyanine dyes, homopolar cyanine dyes, Contains styryl dyes and hemicyanine dyes. Exemplary spectral sensitizing dyes are disclosed in Research Disclosure, Item 36544, September 1994. Those skilled in the art can synthesize these dyes by the procedures described in the Research Disclosure or F.M. Hamer's The Cyanine dyes and Related Compounds (Interscience Publishers, New yprk, 1964). Further, all the dyes described in JP-A-11-95355 (US Pat. No. 6,054,260), pages 7 to 14 are applied as they are.
[0238]
The compounds of types 1 to 4 of the present invention preferably have a total carbon number of 10 to 60. More preferably, it is 15-50, More preferably, it is 18-40, Most preferably, it is 18-30.
[0239]
The compounds of types 1 to 4 of the present invention are subjected to 1-electron oxidation triggered by exposure of the silver halide photographic light-sensitive material using the compound, and after the subsequent reaction, further 1 electron, or 2 electrons or more depending on the type. Electrons are emitted and oxidized, and the oxidation potential of the first electron is preferably about 1.4 V or less, and more preferably 1.0 V or less. This oxidation potential is preferably higher than 0V, more preferably higher than 0.3V. Accordingly, the oxidation potential is preferably in the range of about 0 to about 1.4V, more preferably about 0.3 to about 1.0V.
[0240]
Here, the oxidation potential can be measured by a cyclic voltammetry technique. Specifically, a sample is dissolved in a solution of acetonitrile: water (including 0.1 M lithium perchlorate) = 80%: 20% (volume%). After bubbling nitrogen gas for 10 minutes, a glassy carbon disk was used as the working electrode, a platinum wire was used as the counter electrode, and a calomel electrode (SCE) was used as the reference electrode at 25 ° C. and 0.1 V / Measured at a potential scanning speed of seconds. The oxidation potential versus SCE is taken at the peak potential of the cyclic voltammetry wave.
[0241]
In the case where the compounds of types 1 to 4 of the present invention are one-electron oxidized and further emit one electron after the subsequent reaction, the subsequent oxidation potential is preferably −0.5 V to −2 V. More preferably, it is -0.7V--2V, More preferably, it is -0.9V--1.6V.
[0242]
In the case where the compound of types 1 to 4 of the present invention is a compound that is oxidized by one electron and emits two or more electrons after the subsequent reaction and is oxidized, there is no particular limitation on the oxidation potential of this latter stage. Absent. This is because the oxidation potential of the second electron and the oxidation potential of the third and subsequent electrons cannot be clearly distinguished, and it is often difficult to accurately measure and distinguish these actually.
[0243]
Next, the compound of type 5 will be described.
A compound of type 5 is represented by XY, where X represents a reducing group, Y represents a leaving group, and a one-electron oxidant produced by one-electron oxidation of the reducing group represented by X is This is a compound capable of releasing X by further elimination of Y with subsequent XY bond cleavage reaction to generate an X radical, from which another electron is emitted. The reaction when such a type 5 compound is oxidized can be represented by the following formula.
[0244]
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[0245]
The compound of type 5 preferably has an oxidation potential of 0 to 1.4V, more preferably 0.3V to 1.0V. The oxidation potential of the radical X · generated in the above reaction formula is preferably −0.7 V to −2.0 V, more preferably −0.9 V to −1.6 V.
[0246]
The compound of type 5 is preferably represented by the general formula (G).
[0247]
General formula (G)
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[0248]
In general formula (G), RED₀Represents a reducing group, L₀Represents a leaving group, R₀And R₀₀Represents a hydrogen atom or a substituent. RED₀ And R₀And R₀And R₀₀And may be bonded to each other to form a ring structure. RED₀Is RED of general formula (C)₂Represents the same group, and the preferred range is also the same. R₀And R₀₀Is R in the general formula (C)_{twenty one}And R_{twenty two}The preferred range is also the same. However, R₀And R₀₀Except for the hydrogen atom, L₀Does not represent the same group. RED₀And R₀May be bonded to each other to form a ring structure, and examples of the ring structure include RED of the general formula (C).₂And R_{twenty one}Examples are the same as in the case of linking to form a ring structure, and the preferred range is also the same. R₀And R₀₀Examples of the ring structure formed by bonding to each other include a cyclopentane ring and a tetrahydrofuran ring. In general formula (G), L₀Is L in the general formula (C)₂The preferred range is also the same.
[0249]
The compound represented by the general formula (G) preferably has an adsorptive group to silver halide or a partial structure of spectral sensitizing dye in the molecule.₀When represents a group other than a silyl group, it does not have two or more adsorptive groups in the molecule at the same time. However, the sulfide group as the adsorptive group here is L₀You may have two or more regardless of this.
[0250]
Examples of the adsorptive group to the silver halide of the compound represented by the general formula (G) include the same adsorptive groups that the compounds of types 1 to 4 of the present invention may have. In addition, all those described as “silver halide adsorbing groups” on pages 4 to 7 of JP-A No. 11-95355 can be mentioned, and preferred ranges are also the same.
The partial structure of the spectral sensitizing dye that the compound represented by the general formula (G) may have is the partial structure of the spectral sensitizing dye that the compounds of types 1 to 4 of the present invention may have. However, at the same time, all those described as “light-absorbing groups” on pages 7 to 14 of JP-A-11-95355 can be mentioned, and the preferred ranges are also the same.
[0251]
Specific examples of the compounds of types 1 to 5 of the present invention are listed below, but the present invention is not limited thereto.
[0252]
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[0253]
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[0254]
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[0255]
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[0256]
The compounds of types 1 to 4 of the present invention are described in detail in Japanese Patent Application No. 2002-192373, Japanese Patent Application No. 2002-188537, Japanese Patent Application No. 2002-188536, Japanese Patent Application No. 2001-272137, and Japanese Patent Application No. 2002-192374, respectively. Same as described compound. Specific compound examples described in these patent application specifications can also be given as specific examples of the compounds of types 1 to 4 of the present invention. The synthesis examples of the compounds of types 1 to 4 of the present invention are also the same as those described in these patents.
[0257]
Specific examples of the compound of type 5 according to the present invention are further described in JP-A-9-211769 (compounds PMT-1 to S-37 described in Table E and Table F on pages 28 to 32), JP-A-9-211774. JP-A-11-95355 (compounds INV1-36), JP-T-2001-500996 (compounds 1-74, 80-87, 92-122), US Pat. No. 5,747,235, US Pat. No. 5,747, No. 236, European Patent No. 786692A1 (compounds INV1 to 35), European Patent No. 893732A1, US Pat. No. 6,054,260, US Pat. No. 5,994,051, etc. Examples of compounds referred to as “deprotonated electron donating sensitizers” are mentioned as they are.
[0258]
The compounds of types 1 to 5 of the present invention may be used at any time during the process of producing a photothermographic material when preparing a photosensitive silver halide emulsion. For example, at the time of photosensitive silver halide grain formation, desalting step, chemical sensitization, before coating. Moreover, it can also add in several steps in these processes. The addition position is preferably from the end of formation of the photosensitive silver halide grains to before the desalting step, at the time of chemical sensitization (immediately after the start of chemical sensitization to immediately after completion), and before application, more preferably from the time of chemical sensitization. Until before mixing with the non-photosensitive organic silver salt.
[0259]
The compounds of types 1 to 5 of the present invention are preferably added after being dissolved in water, a water-soluble solvent such as methanol or ethanol, or a mixed solvent thereof. When the compound is dissolved in water, the compound having higher solubility when the pH is increased or decreased may be dissolved at a higher or lower pH and added.
[0260]
The compounds of types 1 to 5 of the present invention are preferably used in emulsion layers containing a photosensitive silver halide and a non-photosensitive organic silver salt, but contain a photosensitive silver halide and a non-photosensitive organic silver salt. It may be added to the protective layer or intermediate layer together with the emulsion layer to be diffused during coating. The timing of addition of the compound of the present invention is preferably before or after the sensitizing dye, and preferably 1 × 10 5 per mole of silver halide.^-9~ 5x10^-1Mole, more preferably 1 × 10^-8~ 5x10^-2It is contained in the silver halide emulsion layer in a molar ratio.
[0261]
10) Combined use of multiple silver halides
The light-sensitive silver halide emulsion in the light-sensitive material used in the present invention may be one kind or two or more kinds (for example, those having different average grain sizes, different halogen compositions, different crystal habits, chemical increase). Those with different feeling conditions) may be used in combination. The gradation can be adjusted by using a plurality of types of photosensitive silver halides having different sensitivities. As technologies related to these, JP-A-57-119341, 53-106125, 47-3929, 48-55730, 46-5187, 50-73627, 57-150841, etc. Can be mentioned. As the sensitivity difference, it is preferable that each emulsion has a difference of 0.2 logE or more.
[0262]
11) Application amount
The amount of photosensitive silver halide added is 1m of photosensitive material.²Indicated by the amount of silver applied per unit, 0.03 to 0.6 g / m²Preferably, 0.05 to 0.4 g / m²More preferably, 0.07 to 0.3 g / m²The photosensitive silver halide is preferably 0.01 mol or more and 0.5 mol or less, more preferably 0.02 mol or more and 0.3 mol or less, still more preferably 0.03 mol or more and 0.2 mol per 1 mol of the organic silver salt. It is as follows.
[0263]
12) Mixing of photosensitive silver halide and organic silver salt
Regarding the mixing method and mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the silver halide grains and organic silver salt that were prepared respectively were mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer. Etc., or a method of preparing an organic silver salt by mixing photosensitive silver halide that has been prepared at any timing during the preparation of the organic silver salt, etc., but the effect of the present invention is sufficient As long as it appears in, there is no particular limitation. Moreover, mixing two or more organic silver salt aqueous dispersions and two or more photosensitive silver salt aqueous dispersions when mixing is a preferred method for adjusting photographic characteristics.
[0264]
13) Mixing silver halide into coating solution
The preferred addition time of the silver halide of the present invention to the image-forming layer coating solution is from 180 minutes before coating to immediately before, preferably from 60 minutes to 10 seconds before coating. There is no particular limitation as long as the effect is sufficiently exhibited. Specific mixing methods include mixing in a tank in which the average residence time calculated from the addition flow rate and the amount of liquid delivered to the coater is the desired time, and by N. Harnby, MFEdwards, AWNienow, Takahashi There is a method of using a static mixer or the like described in Chapter 8 of the translation of Koji “Liquid Mixing Technology” (published by Nikkan Kogyo Shimbun, 1989).
[0265]
(Description of antifogging agent)
Antifoggants, stabilizers and stabilizer precursors which can be used in the present invention are disclosed in paragraph No. 0070 of JP-A-10-62899, page 20 line 57 to page 21 line 7 of EP 080364A1. And the compounds described in JP-A-9-281637 and 9-329864, US Pat. Nos. 6,083,681, 6,083,681, and EP 1048975. Antifoggants preferably used in the present invention are organic halides, and examples thereof include those disclosed in Japanese Patent Application Laid-Open No. 11-65021, paragraphs 0111 to 0112. In particular, an organic halogen compound represented by formula (P) in JP-A-2000-284399, an organic polyhalogen compound represented by formula (II) in JP-A-10-339934, JP-A-2001-31644 and JP The organic polyhalogen compounds described in 2001-33911 are preferred.
[0266]
(Description of polyhalogen compounds)
Hereinafter, the organic polyhalogen compound preferable in the present invention will be specifically described.
A preferred polyhalogen compound of the present invention is a compound represented by the following general formula (H).
General formula (H)
Q- (Y) n-C (Z₁) (Z₂) X
In the general formula (H), Q represents an alkyl group, an aryl group or a heterocyclic group, Y represents a divalent linking group, n represents 0 or 1, Z₁And Z₂Represents a halogen atom, and X represents a hydrogen atom or an electron withdrawing group.
In general formula (H), Q is preferably an aryl group or a heterocyclic group.
In the general formula (H), when Q is a heterocyclic group, a nitrogen-containing heterocyclic group containing 1 to 2 nitrogen atoms is preferable, and a 2-pyridyl group and a 2-quinolyl group are particularly preferable.
In general formula (H), when Q is an aryl group, Q preferably represents a phenyl group substituted with an electron-attracting group having a positive Hammett's substituent constant σp. Regarding the Hammett's substituent constant, Journal of Medicinal Chemistry, 1973, Vol. 16, No. 11, 1207-1216, etc. can be referred to. Examples of such an electron withdrawing group include a halogen atom (fluorine atom (σp value: 0.06), chlorine atom (σp value: 0.23), bromine atom (σp value: 0.23), iodine atom. (Σp value: 0.18)), trihalomethyl group (tribromomethyl (σp value: 0.29), trichloromethyl (σp value: 0.33), trifluoromethyl (σp value: 0.54)), Cyano group (σp value: 0.66), nitro group (σp value: 0.78), aliphatic / aryl or heterocyclic sulfonyl group (for example, methanesulfonyl (σp value: 0.72)), aliphatic / aryl Or a heterocyclic acyl group (for example, acetyl (σp value: 0.50), benzoyl (σp value: 0.43)), alkynyl group (for example, C≡CH (σp value: 0.23)), aliphatic Aryl or heterocyclic oxycarbo Group (for example, methoxycarbonyl (σp value: 0.45), phenoxycarbonyl (σp value: 0.44)), carbamoyl group (σp value: 0.36), sulfamoyl group (σp value: 0.57), Examples thereof include a sulfoxide group, a heterocyclic group, and a phosphoryl group. The σp value is preferably in the range of 0.2 to 2.0, more preferably in the range of 0.4 to 1.0. Particularly preferred as the electron withdrawing group is a carbamoyl group, an alkoxycarbonyl group, an alkylsulfonyl group or an alkylphosphoryl group, and among them, a carbamoyl group is most preferred.
X is preferably an electron-withdrawing group, more preferably a halogen atom, aliphatic / aryl or heterocyclic sulfonyl group, aliphatic / aryl or heterocyclic acyl group, aliphatic / aryl or heterocyclic oxycarbonyl group, A carbamoyl group and a sulfamoyl group, particularly preferably a halogen atom. Among the halogen atoms, a chlorine atom, a bromine atom and an iodine atom are preferable, a chlorine atom and a bromine atom are more preferable, and a bromine atom is particularly preferable.
Y is preferably -C (= O)-, -SO- or -SO.₂ -, More preferably -C (= O)-, -SO₂ -, Particularly preferably -SO₂ -. n represents 0 or 1, and is preferably 1.
[0267]
Specific examples of the compound of the general formula (H) of the present invention are shown below.
[0268]
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[0269]
Other preferred polyhalogen compounds of the invention include those described in JP-A Nos. 2001-31644, 2001-56526, and 2001-209145.
The compound represented by the general formula (H) of the present invention is 10 per mole of the non-photosensitive silver salt of the image forming layer.^-FourIt is preferably used in the range of ˜1 mol, more preferably 10^-3In the range of ~ 0.5 mol, more preferably 1 × 10^-2It is preferable to use in the range of ~ 0.2 mol.
In the present invention, the antifoggant is added to the light-sensitive material by the method described in the method for containing a reducing agent, and the organic polyhalogen compound is also preferably added as a solid fine particle dispersion.
[0270]
(Other antifoggants)
Examples of other antifoggants include mercury (II) salts described in JP-A No. 11-65021, paragraph No. 0113, benzoic acids listed in paragraph No. 0114, salicylic acid derivatives of JP-A No. 2000-206642, and formulas of JP-A No. 2000-221634 A formalin scavenger compound represented by (S), a triazine compound according to claim 9 of JP-A-11-352624, a compound represented by formula (III) of JP-A-61-11791, 4-hydroxy-6- And methyl-1,3,3a, 7-tetrazaindene.
[0271]
The photothermographic material in the invention may contain an azolium salt for the purpose of fog prevention. Examples of the azolium salt include compounds represented by general formula (XI) described in JP-A-59-193447, compounds described in JP-B-55-12581, and general formula (II) described in JP-A-60-153039. And the compounds represented. The azolium salt may be added to any part of the photosensitive material, but the addition layer is preferably added to the layer having the photosensitive layer, and more preferably to the organic silver salt-containing layer. The azolium salt may be added in any step of preparing the coating solution. When added to the organic silver salt-containing layer, any step from the preparation of the organic silver salt to the preparation of the coating solution may be performed. To immediately before coating. The azolium salt may be added by any method such as powder, solution, fine particle dispersion. Moreover, you may add as a solution mixed with other additives, such as a sensitizing dye, a reducing agent, and a color toning agent. In the present invention, the addition amount of the azolium salt may be any amount, but is 1 × 10 10 per mole of silver.^-6Moles to 2 moles, preferably 1 × 10^-3More preferably, it is more than mol and less than 0.5 mol.
[0272]
(Other additives)
1) Mercapto, disulfide, and thiones
In the present invention, a mercapto compound, a disulfide compound, and a thione compound can be contained in order to suppress or promote development to control development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. JP-A-10-62899, Paragraph Nos. 20 pages, lines 36-56. Of these, mercapto-substituted heteroaromatic compounds described in JP-A-9-297367, JP-A-9-304875, JP-A-2001-100358, Japanese Patent Application 2001-104213, Japanese Patent Application 2001-104214, and the like are preferable.
[0273]
2) Color preparation
In the photothermographic material of the present invention, it is preferable to add a color toning agent. For the color toning agent, paragraph numbers 0054 to 0055 of JP-A-10-62899, page 21 lines 23 to 48 of European Patent Publication No. 0803684A1, No. 2000-356317 and JP-A 2000-187298. In particular, phthalazinones (phthalazinone, phthalazinone derivatives or metal salts; for example, 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7 -Dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione); phthalazinones and phthalic acids (eg phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid, diammonium phthalate, sodium phthalate) , Potassium phthalate and tetrachlorophthalic anhydride); phthalazines (phthalazine, phthalazine derivatives or metal salts; eg 4- (1-naphthyl) phthalazine, 6-isopropyl (Thalazine, 6-t-butyl phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine and 2,3-dihydrophthalazine); a combination of phthalazines and phthalic acids is preferred, especially phthalazines and phthalic acids The combination of is preferable. Of these, a particularly preferred combination is a combination of 6-isopropylphthalazine and phthalic acid or 4-methylphthalic acid.
[0274]
3) Plasticizer, lubricant
Plasticizers and lubricants that can be used in the photothermographic material of the invention are described in paragraph No. 0117 of JP-A No. 11-65021. The slip agents are described in JP-A No. 11-84573, paragraph numbers 0061 to 0064 and Japanese Patent Application No. 11-106881, paragraph numbers 0049 to 0062.
[0275]
4) Dyes and pigments
Various dyes and pigments (for example, CIPigment Blue 60, CIPigment Blue 64, and CIPigment Blue 15: 6) are used for the photosensitive layer of the present invention from the viewpoints of improving color tone, preventing interference fringes during laser exposure, and preventing irradiation. Can be used. These are described in detail in WO98 / 36322, JP-A-10-268465, JP-A-11-338098 and the like.
[0276]
5) Ultra-high contrast agent
In order to form an ultrahigh contrast image suitable for printing plate making applications, it is preferable to add an ultrahigh contrast agent to the image forming layer. As for the ultra-high contrast agent and its addition method and addition amount, the formulas of JP-A No. 11-65021, paragraph No. 0118, JP-A No. 11-223898, paragraph Nos. 0136 to 0193, and Japanese Patent Application No. 11-87297 ( H), compounds of formulas (1) to (3), formulas (A) and (B), compounds of general formulas (III) to (V) described in Japanese Patent Application No. 11-91652 (specific compounds: 21 to 24), and the contrast accelerators are described in JP-A-11-65021, paragraph number 0102, and JP-A-11-223898, paragraph number 0194-0195.
[0277]
In order to use formic acid or formate as a strong fogging substance, it is preferably contained in an amount of 5 mmol or less, more preferably 1 mmol or less per mol of silver on the side having an image forming layer containing photosensitive silver halide.
[0278]
When the ultrahigh contrast agent is used in the photothermographic material of the present invention, it is preferable to use an acid formed by hydrating diphosphorus pentoxide or a salt thereof in combination. Acids or salts thereof formed by hydration of diphosphorus pentoxide include metaphosphoric acid (salt), pyrophosphoric acid (salt), orthophosphoric acid (salt), triphosphoric acid (salt), tetraphosphoric acid (salt), hexametalin An acid (salt) etc. can be mentioned. Examples of the acid or salt thereof formed by hydrating diphosphorus pentoxide particularly preferably include orthophosphoric acid (salt) and hexametaphosphoric acid (salt). Specific examples of the salt include sodium orthophosphate, sodium dihydrogen orthophosphate, sodium hexametaphosphate, and ammonium hexametaphosphate.
Amount of acid or salt thereof formed by hydration of diphosphorus pentoxide (1m photosensitive material)²The coating amount per unit) may be a desired amount according to the performance such as sensitivity and fog, but 0.1 to 500 mg / m²Is preferred, 0.5-100 mg / m²Is more preferable.
The reducing agent, hydrogen bonding compound, development accelerator and polyhalogen compound of the present invention are preferably used as solid dispersions, and a preferred method for producing these solid dispersions is described in JP-A-2002-55405. .
[0279]
(Preparation and application of coating solution)
The preparation temperature of the image forming layer coating solution of the present invention is preferably from 30 ° C. to 65 ° C., more preferably from 35 ° C. to less than 60 ° C., and more preferably from 35 ° C. to 55 ° C. Further, it is preferable that the temperature of the image forming layer coating solution immediately after the addition of the polymer latex is maintained at 30 ° C. or more and 65 ° C. or less.
[0280]
(Layer structure and components)
The image forming layer of the present invention is composed of one or more layers on a support. In the case of a single layer, it consists of an organic silver salt, a photosensitive silver halide, a reducing agent and a binder, and optionally contains additional materials such as toning agents, coating aids and other auxiliary agents. In the case of two or more layers, the first image forming layer (usually the layer adjacent to the support) contains an organic silver salt and a light-sensitive silver halide, and some of the second image forming layer or both layers include Must contain other ingredients. The construction of a multicolor photosensitive photothermographic material may include a combination of these two layers for each color and includes all components in a single layer as described in US Pat. No. 4,708,928. Also good. In the case of a multi-dye multicolor photosensitive photothermographic material, each emulsion layer generally has a functional or non-functional barrier layer between each photosensitive layer as described in U.S. Pat.No. 4,460,681. By using, they are kept distinguished from each other.
The photothermographic material of the present invention can have a non-photosensitive layer in addition to the image forming layer. The non-photosensitive layer consists of (a) a surface protective layer provided on the image forming layer (on the side farther from the support), (b) between the plurality of image forming layers and between the image forming layer and the protective layer. An intermediate layer provided between them, (c) an undercoat layer provided between the image forming layer and the support, and (d) a back layer provided on the opposite side of the image forming layer.
[0281]
In addition, although a layer acting as an optical filter can be provided, it is provided as the layer (a) or (b). The antihalation layer is provided on the photosensitive material as the layer (c) or (d).
[0282]
1) Surface protective layer
In the photothermographic material of the invention, a surface protective layer can be provided for the purpose of preventing adhesion of the image forming layer. The surface protective layer may be a single layer or a plurality of layers.
The surface protective layer is described in JP-A No. 11-65021, paragraph numbers 0119 to 0120 and JP-A No. 2000-171936.
As the binder for the surface protective layer of the present invention, gelatin is preferable, but it is also preferable to use polyvinyl alcohol (PVA) or a combination thereof. As gelatin, inert gelatin (for example, Nitta gelatin 750), phthalated gelatin (for example, Nitta gelatin 801), and the like can be used. Examples of PVA include those described in JP-A No. 2000-171936, paragraphs 0009 to 0020, which are completely saponified PVA-105, partially saponified PVA-205, PVA-335, and modified polyvinyl alcohol MP-. Preferred is 203 (trade name, manufactured by Kuraray Co., Ltd.). Polyvinyl alcohol coating amount of protective layer (per layer) (support 1m²As per) 0.3-4.0g / m²Is preferably 0.3 to 2.0 g / m²Is more preferable.
[0283]
Total binder (including water-soluble polymer and latex polymer) coating amount of surface protective layer (per layer) (support 1m²As per) 0.3-5.0g / m²Is preferably 0.3 to 2.0 g / m²Is more preferable.
[0284]
2) Antihalation layer
In the photothermographic material of the present invention, the antihalation layer can be provided on the side far from the light source with respect to the photosensitive layer.
[0285]
For the antihalation layer, paragraphs 0123 to 0124 of JP-A-11-65021, JP-A-11-223898, 9-230531, 10-36695, 10-104779, 11-231457, 11 -352625, 11-352626, etc.
The antihalation layer contains an antihalation dye having absorption at the exposure wavelength. When the exposure wavelength is in the infrared region, an infrared absorbing dye may be used, and in that case, a dye having no absorption in the visible region is preferable.
When antihalation is performed using a dye having absorption in the visible range, it is preferable that substantially no dye color remains after image formation, and a means for decoloring by the heat of heat development is used. In particular, it is preferable to add a thermally decolorable dye and a base precursor to the non-photosensitive layer to function as an antihalation layer. These techniques are described in JP-A-11-231457 and the like.
[0286]
The amount of decoloring dye added is determined by the use of the dye. In general, the optical density (absorbance) measured at the target wavelength is used in an amount exceeding 0.1. The optical density is preferably 0.15 to 2, and more preferably 0.2 to 1. The amount of dye used to obtain such an optical density is generally 0.001 to 1 g / m.²Degree.
[0287]
When the dye is decolored in this way, the optical density after heat development can be reduced to 0.1 or less. Two or more kinds of decoloring dyes may be used in combination in a heat decoloring type recording material or a photothermographic material. Similarly, two or more kinds of base precursors may be used in combination.
In the thermal decoloration using such decoloring dye and base precursor, a substance (for example, diphenylsulfone, which lowers the melting point by 3 ° C. (deg) or more when mixed with a base precursor as described in JP-A-11-352626). 4-Chlorophenyl (phenyl) sulfone), 2-naphthyl benzoate and the like are preferably used in view of thermal decoloring properties.
[0288]
3) Back layer
The back layer applicable to the present invention is described in paragraph numbers 0128 to 0130 of JP-A No. 11-65021.
[0289]
In the present invention, a colorant having an absorption maximum at 300 to 450 nm can be added for the purpose of improving silver tone and aging of the image. Such colorants are disclosed in JP-A Nos. 62-210458, 63-104046, 63-103235, 63-208846, 63-306436, 63-314535, and JP-A-01-61745. No. 1, Japanese Patent Laid-Open No. 2001-100363, and the like.
Such colorants are usually 0.1 mg / m²~ 1g / m²The back layer provided on the opposite side of the photosensitive layer is preferable as the layer to be added in the range of.
In order to adjust the base color tone, it is preferable to use a dye having an absorption peak at 580 to 680 nm. As the dye for this purpose, an azomethine oil-soluble dye described in JP-A-4-359967 and JP-A-4-359968 having a small absorption intensity on the short wavelength side, and a phthalocyanine water-soluble dye described in Japanese Patent Application No. 2002-96797 are preferable. The dye for this purpose may be added to any layer, but is more preferably added to the non-photosensitive layer on the emulsion surface side or the back surface side.
[0290]
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 the support and a back layer on the other side. preferable.
[0291]
4) Matting agent
In the present invention, it is preferable to add a matting agent for improving transportability, and the matting agent is described in paragraph Nos. 0126 to 0127 of JP-A No. 11-65021. Matting agent is photosensitive material 1m²When expressed in terms of coating amount per unit, preferably 1 to 400 mg / m², More preferably 5 to 300 mg / m²It is.
In the present invention, the shape of the matting agent may be either a regular shape or an irregular shape, but is preferably a regular shape, and a spherical shape is preferably used. The average particle size is preferably 0.5 to 10 μm, more preferably 1.0 to 8.0 μm, and still more preferably 2.0 to 6.0 μm. The variation coefficient of the size distribution is preferably 50% or less, more preferably 40% or less, and still more preferably 30% or less. Here, the coefficient of variation is a value represented by (standard deviation of particle size) / (average value of particle size) × 100. It is also preferable to use two types of matting agents having a small variation coefficient and having an average particle size ratio larger than 3.
The emulsion surface may have any matte degree as long as no stardust failure occurs, but the Beck smoothness is preferably 30 seconds or more and 2000 seconds or less, particularly preferably 40 seconds or more and 1500 seconds or less. The Beck smoothness can be easily obtained by Japanese Industrial Standard (JIS) P8119 “Smoothness test method using Beck tester for paper and paperboard” and TAPPI standard method T479.
[0292]
In the present invention, the matte degree of the back layer is preferably a Beck smoothness of 1200 seconds or less and 10 seconds or more, preferably 800 seconds or less and 20 seconds or more, and more preferably 500 seconds or less and 40 seconds or more.
[0293]
In the present invention, the matting agent is preferably contained in the outermost surface layer of the photosensitive material, the layer functioning as the outermost surface layer, or a layer close to the outer surface, and is contained in a layer acting as a so-called protective layer. It is preferable.
[0294]
5) Polymer latex
In particular, when the photothermographic material of the present invention is used for printing applications in which dimensional change is a problem, it is preferable to use a polymer latex for the surface protective layer or the back layer. For such polymer latex, “Synthetic resin emulsion (Hiraku Okuda, Hiroshi Inagaki, published by Kobunshi Publishing (1978))”, “Application of synthetic latex (Takaaki Sugimura, Ikuo Kataoka, Junichi Suzuki, Keiji Kasahara, Takashi "Molecular Publications (1993))" and "Synthetic Latex Chemistry (Souichi Muroi, published by High Polymers Publication (1970))", specifically, methyl methacrylate (33.5% by mass) / ethyl Latex of acrylate (50% by mass) / methacrylic acid (16.5% by mass) copolymer, latex of methyl methacrylate (47.5% by mass) / butadiene (47.5% by mass) / itaconic acid (5% by mass), ethyl acrylate / methacrylic acid Copolymer latex, methyl methacrylate (58.9% by mass) / 2-ethylhexyl acrylate (25.4% by mass) / styrene (8.6% by mass) / 2-hydro Latex of methyl methacrylate (5.1 mass%) / acrylic acid (2.0 mass%) copolymer, methyl methacrylate (64.0 mass%) / styrene (9.0 mass%) / butyl acrylate (20.0 mass%) / 2-hydroxyethyl methacrylate (5.0 Mass%) / acrylic acid (2.0 mass%) copolymer latex and the like. Further, as a binder for the surface protective layer, a combination of polymer latex described in Japanese Patent Application No. 11-6872 and the technique described in Paragraph Nos. 0021 to 0025 of Japanese Patent Application Laid-Open No. 2000-267226, Japanese Patent Application No. 11-6872 The technology described in paragraph numbers 0027 to 0028 of the specification and the technology described in paragraph numbers 0023 to 0041 of JP 2000-19678 may be applied. The ratio of the polymer latex in the surface protective layer is preferably 10% by mass or more and 90% by mass or less, and particularly preferably 20% by mass or more and 80% by mass or less of the total binder.
[0295]
6) Membrane pH
The photothermographic material of the present invention preferably has a film surface pH of 7.0 or less, more preferably 6.6 or less before heat development. The lower limit is not particularly limited, but is about 3. The most preferred pH range is in the range of 4 to 6.2. The film surface pH is preferably adjusted using an organic acid such as a phthalic acid derivative, a non-volatile acid such as sulfuric acid, or a volatile base such as ammonia from the viewpoint of reducing the film surface pH. In particular, ammonia is volatile and is preferable for achieving a low film surface pH because it can be removed before the coating process or heat development.
In addition, it is also preferable to use ammonia in combination with a nonvolatile base such as sodium hydroxide, potassium hydroxide, or lithium hydroxide. A method for measuring the film surface pH is described in paragraph No. 0123 of JP-A-2000-284399.
[0296]
7) Hardener
A hardener may be used for each layer such as the photosensitive layer, protective layer, and back layer of the present invention. Examples of hardeners are THJames' “THE THEORY OF THE PHOTOGRAPHIC PROCESS FOURTH EDITION” (Macmillan Publishing Co., Inc., published in 1977), each of the methods described on pages 77 to 87, Chrome Alum, 2 , 4-Dichloro-6-hydroxy-s-triazine sodium salt, N, N-ethylenebis (vinylsulfoneacetamide), N, N-propylenebis (vinylsulfoneacetamide) and polyvalent metals described on page 78 Ions, polyisocyanates such as US Pat. No. 4,281,060 and JP-A-6-208193, epoxy compounds such as US Pat. No. 4,791,042, and vinyl sulfone compounds such as JP-A 62-89048 are preferably used.
[0297]
The hardener is added as a solution, and the addition time of this solution into the protective layer coating solution is from 180 minutes before to immediately before application, preferably from 60 minutes to 10 seconds before application. As long as the effects of the present invention are sufficiently exhibited, there is no particular limitation. Specific mixing methods include mixing in a tank in which the average residence time calculated from the addition flow rate and the amount of liquid delivered to the coater is the desired time, and by N. Harnby, MFEdwards, AWNienow, Takahashi There is a method of using a static mixer or the like described in Chapter 8 of the translation of Koji “Liquid Mixing Technology” (published by Nikkan Kogyo Shimbun, 1989).
[0298]
8) Surfactant
JP-A-11-65021 paragraph number 0132 for surfactants applicable to the present invention, paragraph number 0133 for solvents, paragraph number 0134 for supports, paragraph number for antistatic or conductive layers The method for obtaining a color image is described in paragraph No. 0136 of the same publication, and the slip agent is described in paragraph Nos. 0061 to 0064 of JP-A No. 11-84573 and paragraph Nos. 0049 to 0062 of Japanese Patent Application No. 11-106881.
In the present invention, it is preferable to use a fluorosurfactant. Specific examples of the fluorosurfactant include compounds described in JP-A-10-197985, JP-A-2000-19680, JP-A-2000-214554, and the like. In addition, polymeric fluorine-based surfactants described in JP-A-9-281636 are also preferably used. In the photothermographic material of the present invention, it is preferable to use a fluorosurfactant described in JP-A No. 2002-82411, Japanese Patent Application Nos. 2001-242357 and 2001-264110. In particular, the fluorosurfactants described in Japanese Patent Application Nos. 2001-242357 and 2001-264110 are preferable in terms of charge adjustment ability, stability of the coated surface, and smoothness when coating and manufacturing with an aqueous coating solution. The fluorine-based surfactant described in Japanese Patent Application No. 2001-264110 is most preferable in that it has a high charge control capability and requires a small amount of use.
In the present invention, the fluorosurfactant can be used on either the emulsion surface or the back surface, and is preferably used on both surfaces. Further, it is particularly preferable to use in combination with a conductive layer containing the above-described metal oxide. In this case, sufficient performance can be obtained even if the amount of the fluorosurfactant used on the surface having the conductive layer is reduced or removed.
The preferred amount of fluorosurfactant used is 0.1 mg / m for each of the emulsion surface and back surface²~ 100mg / m²In the range, more preferably 0.3 mg / m²~ 30mg / m²Range, more preferably 1 mg / m²~ 10mg / m²Range. In particular, the fluorosurfactant described in Japanese Patent Application No. 2001-264110 has a large effect and is 0.01 to 10 mg / m.²Is preferably in the range of 0.1 to 5 mg / m²The range of is more preferable.
[0299]
9) Antistatic agent
In the present invention, it is preferable to have a conductive layer containing a metal oxide or a conductive polymer. The antistatic layer may serve as an undercoat layer, a back layer surface protective layer, or the like, or may be provided separately. As the conductive material for the antistatic layer, a metal oxide in which conductivity is improved by introducing oxygen defects or different metal atoms into the metal oxide is preferably used. Examples of metal oxides are ZnO, TiO₂, SnO₂And for ZnO, addition of Al and In, SnO₂For Sb, Nb, P, halogen elements, etc., TiO₂In contrast, addition of Nb, Ta or the like is preferable. Especially SnO with Sb added₂Is preferred. The amount of different atoms added is preferably in the range of 0.01 to 30 mol%, more preferably in the range of 0.1 to 10 mol%. The shape of the metal oxide may be spherical, needle-like, or plate-like, but needle-like particles having a long axis / uniaxial ratio of 2.0 or more, preferably 3.0 to 50 are preferable from the viewpoint of providing conductivity. The amount of metal oxide used is preferably 1 mg / m²~ 1000mg / m²In the range, more preferably 10 mg / m²~ 500mg / m²Range, more preferably 20 mg / m²~ 200mg / m²Range. The antistatic layer of the present invention may be disposed on either the emulsion surface side or the back surface side, but is preferably disposed between the support and the back layer. Specific examples of the antistatic layer of the present invention are disclosed in paragraph No. 0135 of JP-A-11-65021, JP-A-56-143430, JP-A-56-143431, JP-A-58-62646, JP-A-56-120519, JP-A-11- No. 84573, paragraph numbers 0040 to 0051, US Pat. No. 5,575,957, and JP-A No. 11-223898, paragraph numbers 0078 to 0084.
[0300]
10) Support
The transparent support is a polyester, particularly polyethylene, which has been heat-treated in a temperature range of 130 to 185 ° C. in order to relieve internal strain remaining in the film during biaxial stretching and to eliminate thermal shrinkage strain generated during heat development. Terephthalate is preferably used. In the case of a photothermographic material for medical use, the transparent support may be colored with a blue dye (for example, dye-1 described in Examples of JP-A-8-240877) or may be uncolored. Examples of the support include water-soluble polyesters disclosed in JP-A-11-84574, styrene-butadiene copolymers described in JP-A-10-186565, and vinylidene chloride described in JP-A-2000-39684 and JP-A-11-106881, paragraphs 0063 to 0080. It is preferable to apply an undercoating technique such as a copolymer. When the emulsion layer or the back layer is coated on the support, the water content of the support is preferably 0.5 wt% or less.
[0301]
11) Other additives
An antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, or a coating aid may be further added to the photothermographic material. Various additives are added to either the photosensitive layer or the non-photosensitive layer. For these, reference can be made to WO98 / 36322, EP803764A1, JP-A-10-186567, 10-18568 and the like.
[0302]
12) Application method
The photothermographic material in the invention may be applied by any method. Specifically, various coating operations are used, including extrusion coating, slide coating, curtain coating, dip coating, knife coating, flow coating, or extrusion coating using a hopper of the type described in U.S. Pat. Stephen F. Kistler and Petert M. Schweizer “LIQUID FILM COATING” (CHAPMAN & HALL, 1997) pages 399 to 536, preferably used for extrusion coating or slide coating, particularly preferably for slide coating It is done. An example of the shape of the slide coater used for slide coating is shown in Figure 11b.1 on page 427 of the same book. If desired, two or more layers can be coated simultaneously by the method described in pages 399 to 536 of the same document, the method described in US Pat. No. 2,761,791 and British Patent No. 837,095. Particularly preferred coating methods in the present invention are those described in JP-A Nos. 2001-194748, 2002-153808, 2002-153803, and 2002-182333.
[0303]
The organic silver salt-containing layer coating solution in the present invention is preferably a so-called thixotropic fluid. Regarding this technique, JP-A-11-52509 can be referred to. The organic silver salt-containing layer coating solution in the present invention has a shear rate of 0.1 S.^-1The viscosity in is preferably 400 mPa · s or more and 100,000 mPa · s or less, and more preferably 500 mPa · s or more and 20,000 mPa · s or less. Also, shear rate 1000S^-1Is preferably 1 mPa · s or more and 200 mPa · s or less, and more preferably 5 mPa · s or more and 80 mPa · s or less.
[0304]
In the case of preparing the coating liquid of the present invention, a known in-line mixer or implant mixer is preferably used when mixing two kinds of liquids. A preferred in-line mixer of the present invention is described in JP-A-2002-85948, and an implant mixer is described in JP-A-2002-90940.
The coating solution in the present invention is preferably subjected to defoaming treatment in order to keep the coated surface state good. A preferred defoaming treatment method of the present invention is the method described in JP-A-2002-66431.
When applying the coating solution of the present invention, it is preferable to perform static elimination in order to prevent adhesion of dust, dust, and the like due to electric resistance of the support. An example of a preferable static elimination method in the present invention is described in JP-A-2002-143747.
In the present invention, it is important to precisely control the drying air and the drying temperature in order to dry the non-setting image forming layer coating solution. The preferred drying method of the present invention is described in detail in JP-A Nos. 2001-194749 and 2002-139814.
The photothermographic material of the present invention is preferably subjected to a heat treatment immediately after coating and drying in order to improve film formability. The temperature of the heat treatment is preferably in the range of 60 ° C. to 100 ° C. as the film surface temperature, and the heating time is preferably in the range of 1 second to 60 seconds. A more preferable range is a film surface temperature of 70 to 90 ° C. and a heating time of 2 to 10 seconds. A preferred heat treatment method of the present invention is described in JP-A No. 2002-107872.
In order to stably and continuously produce the photothermographic material of the present invention, the production methods described in JP-A Nos. 2002-156728 and 2002-182333 are preferably used.
[0305]
The photothermographic material is preferably a mono-sheet type (a type capable of forming an image on the photothermographic material without using another sheet such as an image receiving material).
[0306]
13) Packaging materials
The light-sensitive material of the present invention is preferably packaged with a packaging material having a low oxygen permeability and / or moisture permeability in order to suppress fluctuations in photographic performance during raw storage or to improve curling, curling, etc. Oxygen permeability is 50ml / atm ・ m at 25 ℃²・ It is preferably less than day, more preferably 10 ml / atm · m²・ Day or less, more preferably 1.0ml / atm ・ m²・ It is less than day. Moisture permeability is 10g / atm · m²・ It is preferably less than day, more preferably 5g / atm · m²・ Day or less, more preferably 1g / atm ・ m²・ It is less than day.
Specific examples of the packaging material having a low oxygen permeability and / or moisture permeability are disclosed in, for example, JP-A-8-254793. This is a packaging material described in JP-A-2000-206653.
14) Other available technologies
[0307]
Techniques that can be used for the photothermographic material of the present invention include EP803764A1, EP883022A1, WO98 / 36322, JP 56-62648, 58-62644, JP 9-43766, and 9- 281637, 9-297367, 9-304869, 9-311405, 9-329865, 10-10669, 10-62899, 10-69023, 10-186568, 10-90823, 10-171063, 10-186565, 10-186567, 10-186569 to 10-186572, 10-197974, 10-197982, 10 -197983, 10-197985 to 10-197987, 10-207001, 10-207004, 10-221807, 10-282601, 10-288823, 10-288823, 10-288824 10-307365, 10-312038, 10-339934, 11-7100, 11-15105, 11-24200, 11-24201, 11-30832, 11-84574, 11-65021, 11-109547, 11-125880, 11-129629, 11-133536 to 11-133539, 11-133542, 11 -133543, 11-223898, 11-352627, 11-305377, 11-305378, 11-305384, 11-305380, 11-316435, 11-327076, 11-338096, 11-338098, 11-338099, 11- 343420, JP 2000-187298, 2000-10229, 2000-47345, 2000-206642, 2000-98530, 2000-98531, 2000-112059, 2000-112060 No., 2000-112104, 2000-112064, 2000-171936.
[0308]
In the case of a multicolor color photothermographic material, each emulsion layer generally uses a functional or non-functional barrier layer between each photosensitive layer, as described in US Pat. No. 4,460,681. Thus, they are kept distinguished from each other.
The construction in the case of a multicolor color photothermographic material may include a combination of these two layers for each color, and includes all components in a single layer as described in US Pat. No. 4,708,928. May be.
[0309]
(Image forming method)
1) Exposure
Red to infrared emitting He-Ne laser, red semiconductor laser, or blue to green emitting Ar⁺, He—Ne, He—Cd laser, blue semiconductor laser. In recent years, in particular, a module in which an SHG (Second Harmonic Generator) element and a semiconductor laser are integrated and a blue semiconductor laser have been developed, and a laser output device in a short wavelength region has been closed up.
In the present invention, a blue semiconductor laser is preferably used. The blue semiconductor laser is expected to increase in demand in the future because high-definition image recording is possible, the recording density is increased, and a stable output is obtained with a long lifetime.
The peak wavelength of the blue laser light is preferably 300 nm to 500 nm, particularly preferably 400 nm to 500 nm.
It is also preferable that the laser light is oscillated in a vertical multi by a method such as high frequency superposition.
[0310]
2) Thermal development
The photothermographic material of the present invention may be developed by any method, but is usually developed by raising the temperature of the photothermographic material exposed imagewise. A preferred development temperature is 80 to 250 ° C, preferably 100 to 140 ° C, more preferably 110 to 130 ° C. The development time is preferably 1 to 60 seconds, more preferably 3 to 30 seconds, still more preferably 5 to 25 seconds, and 7 to 15 seconds.
[0311]
Either a drum type heater or a plate type heater may be used as the thermal development method, but the plate type heater method is more preferable. The plate-type heater-based heat development method is preferably the method described in JP-A-11-133572, and a visible image is obtained by bringing the heat-developable photosensitive material on which the latent image has been formed into contact with the heating means in the heat developing section. In the heat development apparatus, the heating unit includes a plate heater, and a plurality of press rollers are disposed to face each other along one surface of the plate heater, and the press roller is disposed between the press roller and the plate heater. A heat development apparatus characterized in that heat development is performed by passing a photothermographic material. It is preferable to divide the plate heater into 2 to 6 stages and lower the temperature about 1 to 10 ° C. at the tip. For example, there are examples in which four sets of plate heaters that can be independently controlled are used and controlled so as to be 112 ° C., 119 ° C., 121 ° C., and 120 ° C., respectively. Such a method is also described in JP-A-54-30032, which can exclude moisture and organic solvents contained in the photothermographic material out of the system, and can be rapidly developed in the photothermographic material. It is also possible to suppress a change in the shape of the support of the photothermographic material due to the heating.
[0312]
In order to reduce the size of the heat developing machine and shorten the heat development time, it is preferable to be able to control the heater more stably. In addition, the exposure of one sheet of photosensitive material is started from the top and the exposure is finished to the rear end. It is desirable to start the heat development before the time. Imagers capable of rapid processing preferred in the present invention are described in, for example, Japanese Patent Application Nos. 2001-088832 and 091114. If this imager is used, for example, heat development can be performed in 14 seconds with a three-stage plate heater controlled at 107 ° C.-121 ° C.-121 ° C., and the output time of the first sheet is reduced to about 60 seconds. be able to. For such rapid development processing, it is preferable to use a photothermographic material which is highly sensitive and hardly affected by environmental temperature.
[0313]
3) System
As a medical laser imager provided with an exposure part and a heat development part, Fuji Medical Dry Laser Imager FM-DPL can be mentioned. FM-DPL is described in Fuji Medical Review No. 8, pages 39 to 55, and it goes without saying that these techniques are applied as a laser imager of the photothermographic material of the present invention. It can also be applied as a photothermographic material for laser imagers in the “AD network” proposed by Fuji Film Medical Co., Ltd. as a network system that conforms to the DICOM standard.
[0314]
(Use of the present invention)
The photothermographic material of the present invention forms a black and white image by a silver image, and is used as a photothermographic material for medical diagnosis, a photothermographic material for industrial photography, a photothermographic material for printing, and a photothermographic material for COM. It is preferably used.
[0315]
【Example】
EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.
Example 1
[0316]
1. Making PET support
1) Film formation
Using terephthalic acid and ethylene glycol, PET having an intrinsic viscosity of IV = 0.66 (measured in phenol / tetrachloroethane = 6/4 (weight ratio) at 25 ° C.) was obtained according to a conventional method. This was pelletized, dried at 130 ° C. for 4 hours, melted at 300 ° C., extruded from a T-type die, and rapidly cooled to prepare an unstretched film having a thickness of 175 μm after heat setting.
[0317]
This was longitudinally stretched 3.3 times using rolls with different peripheral speeds and then stretched 4.5 times with a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. Thereafter, the film was heat-fixed at 240 ° C. for 20 seconds and relaxed by 4% in the lateral direction at the same temperature. After slitting the chuck part of the tenter, knurling is performed on both ends, and 4kg / cm²And a roll having a thickness of 175 μm was obtained.
[0318]
2) Surface corona treatment
Using a solid state corona treatment machine 6KVA model manufactured by Pillar, both surfaces of the support were treated at room temperature at 20 m / min. From the current and voltage readings at this time, the support is 0.375 kV · A · min / m²It was found that the process was done. The treatment frequency at this time was 9.6 kHz, and the gap clearance between the electrode and the dielectric roll was 1.6 mm.
[0319]
3) Undercoat
(1) Preparation of undercoat layer coating solution
Formulation (1) (for the undercoat layer on the photosensitive layer side)
59g pesresin A-520 (30% by mass solution) manufactured by Takamatsu Yushi Co., Ltd.
Polyethylene glycol monononyl phenyl ether
(Average number of ethylene oxide = 8.5) 10% by mass solution 5.4g
MP-1000 by Soken Chemical Co., Ltd. (polymer fine particles, average particle size 0.4μm) 0.91g
935ml distilled water
[0320]
Formulation (2) (for back layer 1st layer)
Styrene-butadiene copolymer latex 158g
(Solid content 40% by mass, styrene / butadiene weight ratio = 68/32)
2,4-dichloro-6-hydroxy-S-triazine sodium salt (8% by weight aqueous solution) 20 g
10% 1% by weight aqueous solution of sodium laurylbenzenesulfonate
Distilled water 854ml
[0321]
Formula (3) (Back side 2nd layer)
SnO₂/ SbO (9/1 mass ratio, average particle size 0.038μm, 17 mass% dispersion) 84g
Gelatin (10 mass% aqueous solution) 89.2g
Metrows TC-5 (2% by weight aqueous solution) manufactured by Shin-Etsu Chemical Co., Ltd.8.6g
MP-1000 0.01g manufactured by Soken Chemical Co., Ltd.
10% 1% by weight aqueous solution of sodium dodecylbenzenesulfonate
NaOH (1% by mass) 6ml
Proxel (ICI) 1ml
805ml of distilled water
[0322]
(2) Undercoat
After both surfaces of the biaxially stretched polyethylene terephthalate support having a thickness of 175 μm are subjected to the corona discharge treatment, the undercoat coating solution formulation {circle around (1)} is applied to one surface (photosensitive layer surface) with a wire bar at a wet coating amount of 6.6. ml / m²(Per side) and dry at 180 ° C. for 5 minutes, and then apply the undercoat coating solution formulation (2) on the back side (back side) with a wire bar at a wet coating amount of 5.7 ml / m.²And then dry at 180 ° C. for 5 minutes, and further apply the above undercoat coating liquid formulation (3) on the back surface (back surface) with a wire bar at a wet coating amount of 7.7 ml / m.²And then dried at 180 ° C. for 6 minutes to prepare an undercoat support.
[0323]
2. Back layer
1) Preparation of back surface coating solution
(Preparation of antihalation layer coating solution)
Gelatin 60 g, polyacrylamide 24.5 g, 1 mol / l sodium hydroxide 2.2 g, monodisperse polymethyl methacrylate fine particles (average particle size 8 μm, particle size standard deviation 0.4) 2.4 g, benzoisothiazolinone 0.08 g, polystyrene sulfonate sodium 0.3 g, 0.21 g of blue dye compound-1, 0.15 g of yellow dye compound-1 and 8.3 g of acrylic acid / ethyl acrylate copolymer latex (copolymerization ratio 5/95) were mixed, and the whole was made up to 818 ml with water. An antihalation layer coating solution was prepared.
[0324]
(Preparation of back surface protective layer coating solution)
Keep container at 40 ° C, gelatin 40 g, liquid paraffin emulsion 1.5 g as liquid paraffin, benzoisothiazolinone 35 mg, 1 mol / l caustic 6.8 g, sodium t-octylphenoxyethoxyethanesulfonate 0.5 g, polystyrene sulfone Sodium sulfate 0.27g, fluorine surfactant (F-1) 2% aqueous solution 5.4m, acrylic acid / ethyl acrylate copolymer (copolymerization mass ratio 5/95) 6.0g, N, N-ethylenebis (vinyl) 2.0 g of sulfoneacetamide) was mixed and made up to 1000 ml with water to obtain a back surface protective layer coating solution.
[0325]
2) Application of each layer on the back surface
An anti-halation layer coating solution is applied to the back surface side of the undercoat support with a gelatin coating amount of 0.88 g / m 2.²In addition, the coating amount of the back surface protective layer is 1.2 g / m for the gelatin coating amount.²Then, a simultaneous multilayer coating was applied and dried to form a back layer.
[0326]
3. Image forming layer, intermediate layer, and surface protective layer
3-1. Preparation of coating materials
1) Preparation of silver halide emulsion
(Preparation of silver halide emulsion 1)
To a solution of 1420 ml of distilled water, 4.3 ml of a 1% by weight potassium iodide solution was added, and a solution containing 3.5 ml of 0.5 mol / L sulfuric acid and 36.7 g of phthalated gelatin was stirred in a stainless steel reaction vessel. While maintaining the liquid temperature at 42c, a solution A in which distilled water was diluted to 22.56 g of silver nitrate and diluted to 195.6 ml and solution B in which 21.8 g of potassium iodide was diluted to a volume of 218 ml with distilled water were added at a constant flow rate. The whole amount was added over a period of minutes. Thereafter, 10 ml of a 3.5% by mass aqueous hydrogen peroxide solution was added, and 10.8 ml of a 10% by mass aqueous solution of benzimidazole was further added.
[0327]
Further, Solution C obtained by adding distilled water to 51.86 g of silver nitrate and diluting to 317.5 ml and Solution D obtained by diluting 60 g of potassium iodide to a volume of 600 ml with distilled water were added to Solution C over 120 minutes at a constant flow rate. Solution D was added by the controlled double jet method while maintaining pAg at 8.1. 1 x 10 per mole of silver^-FourThe total amount of potassium hexachloroiridium (III) was added 10 minutes after the start of the addition of Solution C and Solution D so as to have a molarity. Further, 5 seconds after the completion of the addition of the solution C, an aqueous solution of potassium iron (II) hexacyanide was added at 3 × 10 5^-FourThe whole molar amount was added. The pH was adjusted to 3.8 using 0.5 mol / L sulfuric acid, stirring was stopped, and a precipitation / desalting / water washing step was performed. The pH was adjusted to 5.9 with 1 mol / L sodium hydroxide to prepare a silver halide dispersion having a pAg of 8.0.
[0328]
While maintaining the silver halide dispersion at 38 ° C. with stirring, 5 ml of a 0.34 mass% 1,2-benzisothiazolin-3-one methanol solution was added, and the temperature was raised to 47 ° C. 20 minutes after the temperature rise, sodium benzenethiosulfonate was 7.6 × 10 in 1 mol of silver with a methanol solution.^-Five5 minutes later, tellurium sensitizer B was added in methanol solution to 2.9 × 10 6 per mole of silver.^-FourMole was added and aged for 91 minutes.
1.3 ml of a 0.8 mass% methanol solution of N, N′-dihydroxy-N ″ -diethylmelamine was added, and after 4 minutes, 5-methyl-2-mercaptobenzimidazole was added in methanol solution at a rate of 4. 8 × 10^-3Mole and 1-phenyl-2-heptyl-5-mercapto-1,3,4-triazole in methanol solution at 5.4 × 10 5 per mole of silver^-3A silver halide emulsion 1 was prepared by adding a molar amount.
[0329]
The grains in the prepared silver halide emulsion were pure silver iodide grains having an average sphere equivalent diameter of 0.040 μm and a sphere equivalent diameter variation coefficient of 18%. Moreover, it is a tetrahedral particle | grain which has (001), {100}, {101} face, The ratio of the (gamma) phase was 30% when measured using the X-ray powder diffraction analysis. The particle size and the like were determined from an average of 1000 particles using an electron microscope.
[0330]
(Preparation of silver halide emulsion 2)
The temperature of the reaction solution was changed to 65 ° C., 5 ml of a 5% methanol solution of 2,2 ′-(ethylenedithio) diethanol was added after the addition of solutions A and B, and solution D while maintaining pAg at 10.5. Was added by a controlled double jet method, and 3 minutes after the addition of tellurium sensitizer during chemical sensitization, bromoauric acid was added at 5 × 10 5 per mole of silver.^-FourMoles and potassium thiocyanate 2 x 10 per mole of silver^-3A silver halide emulsion 2 was prepared in the same manner as Emulsion 1 except that mol was added.
Grains in the prepared silver halide emulsion have an average equivalent circle diameter of projected area of 0.164 μm, a grain thickness of 0.032 μm, an average aspect ratio of 5, an average sphere equivalent diameter of 0.11 μm, and a coefficient of variation of the equivalent sphere diameter of 23. % Pure silver iodide tabular grains. When measured using X-ray powder diffraction analysis, the proportion of the γ phase was 80%. The particle size and the like were determined from an average of 1000 particles using an electron microscope.
(Preparation of silver halide emulsion 3)
Silver halide emulsion 3 in exactly the same manner as silver halide emulsion 1 except that the temperature of the reaction solution was changed to 27 ° C. and solution D was added by the controlled double jet method while maintaining pAg at 10.2. It was created.
Grains in the prepared silver halide emulsion were pure silver iodide grains having an average sphere equivalent diameter of 0.022 μm and a sphere equivalent diameter variation coefficient of 17%. Further, they were dodecahedron grains having (001), {1 (-1) 0}, and {101} planes, and were silver iodide substantially consisting of a β phase as measured by X-ray powder diffraction analysis. The particle size and the like were determined from an average of 1000 particles using an electron microscope.
[0331]
(Preparation of mixed emulsion A for coating solution)
Silver halide emulsion 1, silver halide emulsion 2 and silver halide emulsion 3 are dissolved in a molar ratio of 5: 2: 3, and 1 mol of benzothiazolium iodide is added in a 1% by mass aqueous solution. 7 × 10 per^-3Mole was added. Further, water is added so that the content of silver halide per 1 kg of the mixed emulsion for coating solution is 38.2 g as silver, and 1- (3-methylureidophenyl)-is obtained so that the amount is 0.34 g per 1 kg of the mixed emulsion for coating solution. 5-mercaptotetrazole was added.
Further, as “a compound in which a one-electron oxidant produced by one-electron oxidation can emit one electron or more”, compounds 2 and 20 and 26 are each 2 × 10 2 per mole of silver halide silver.^-3Molar amounts were added.
[0332]
2) Preparation of fatty acid silver dispersion
(Preparation of recrystallized behenic acid)
100 kg of behenic acid (product name Edenor C22-85R) manufactured by Henkel was mixed in 1200 kg of isopropyl alcohol, dissolved at 50 ° C., filtered through a 10 μm filter, cooled to 30 ° C., and recrystallized. The cooling speed during recrystallization was controlled at 3 ° C / hour. The obtained crystals were centrifugally filtered, washed with 100 kg of isopropyl alcohol, and then dried. When the obtained crystals were esterified and subjected to GC-FID measurement, the behenic acid content was 96 mol%, in addition, 2 mol% lignoceric acid, 2 mol% arachidic acid, and 0.001 mol% erucic acid were contained. It was.
[0333]
(Preparation of fatty acid silver dispersion)
Recrystallized behenic acid 88 kg, distilled water 422 L, 5 mol / L NaOH aqueous solution 49.2 L and t-butyl alcohol 120 L were mixed and stirred at 75 ° C. for 1 hour to react to obtain sodium behenate solution B. Separately, 206.2 L (pH 4.0) of an aqueous solution of 40.4 kg of silver nitrate was prepared and kept warm at 10 ° C. Keep the reaction vessel containing 635L distilled water and 30L t-butyl alcohol at 30 ° C, and with sufficient agitation, the total amount of sodium behenate solution and the total amount of silver nitrate aqueous solution are 93 minutes and 15 seconds, respectively. And added over 90 minutes. At this time, only the silver nitrate aqueous solution is added for 11 minutes after the start of the addition of the aqueous silver nitrate solution, and then the addition of the sodium behenate solution is started. After the addition of the aqueous silver nitrate solution, only the sodium behenate solution is added for 14 minutes and 15 seconds. It was made to be. At this time, the temperature in the reaction vessel was 30 ° C., and the external temperature was controlled so that the liquid temperature was constant. The pipe of the addition system for the sodium behenate solution was kept warm by circulating hot water outside the double pipe so that the liquid temperature at the outlet at the tip of the addition nozzle was 75 ° C. Moreover, the piping of the addition system of the silver nitrate aqueous solution was kept warm by circulating cold water outside the double pipe. The addition position of the sodium behenate solution and the addition position of the aqueous silver nitrate solution were arranged symmetrically around the stirring axis, and were adjusted so as not to contact the reaction solution.
[0334]
After completion of the addition of the sodium behenate solution, the mixture was left stirring for 20 minutes at the same temperature, heated to 35 ° C. over 30 minutes, and then aged for 210 minutes. Immediately after completion of aging, the solid content was separated by centrifugal filtration, and the solid content was washed with water until the conductivity of filtered water reached 30 μS / cm. Thus, a fatty acid silver salt was obtained. The obtained solid content was stored as a wet cake without drying.
[0335]
When the morphology of the obtained silver behenate particles was evaluated by electron microscope photography, the average value was a = 0.21 μm, b = 0.4 μm, c = 0.4 μm, the average aspect ratio 2.1, and the coefficient of variation of the equivalent sphere diameter was 11%. It was a crystal. (A, b, and c are the provisions of the text)
[0336]
Add 19.3 kg of polyvinyl alcohol (trade name: PVA-217) and water to a wet cake with a dry solid content of 260 kg. PM-10 type).
[0337]
Next, the pre-dispersed stock solution is subjected to a disperser (trade name: Microfluidizer M-610, manufactured by Microfluidics International Corporation, using a Z-type interaction chamber) at a pressure of 1150 kg / cm²And was treated three times to obtain a silver behenate dispersion. The cooling operation was set to a dispersion temperature of 18 ° C. by installing a serpentine heat exchanger before and after the interaction chamber and adjusting the temperature of the refrigerant.
[0338]
3) Preparation of reducing agent dispersion
(Preparation of reducing agent-1 dispersion)
Reducing agent-1 (2,2'-methylenebis- (4-ethyl-6-tert-butylphenol)) 10 kg and denatured polyvinyl alcohol (Kuraray Co., Ltd., POVAL MP203) 10% by weight aqueous solution 16 kg, 10 kg of water Add and mix well to make a slurry. This slurry was fed with a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours, and then 0.2 g of benzoisothiazolinone sodium salt Water was added to prepare a reducing agent concentration of 25% by mass. This dispersion was heat-treated at 60 ° C. for 5 hours to obtain a reducing agent-1 dispersion. The reducing agent particles contained in the reducing agent dispersion thus obtained had a median diameter of 0.40 μm and a maximum particle diameter of 1.4 μm or less. The obtained reducing agent dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust and stored.
[0339]
(Preparation of reducing agent-2 dispersion)
10 mass of reducing agent-2 (6,6'-di-t-butyl-4,4'-dimethyl-2,2'-butylidenediphenol) and modified polyvinyl alcohol (Kuraray Co., Ltd., Poval MP203) 10 kg of water was added to 16 kg of% aqueous solution and mixed well to obtain a slurry. This slurry was fed with a diaphragm pump and dispersed for 3 hours 30 minutes in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm, and then benzoisothiazolinone sodium salt 0.2 g and water were added to prepare a reducing agent concentration of 25% by mass. This dispersion was heated at 40 ° C. for 1 hour, and then further heated at 80 ° C. for 1 hour to obtain a reducing agent-2 dispersion. The reducing agent particles contained in the reducing agent dispersion thus obtained had a median diameter of 0.50 μm and a maximum particle diameter of 1.6 μm or less. The obtained reducing agent dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust and stored.
[0340]
4) Preparation of hydrogen bonding compound dispersion
Add 10 kg of water to 16 kg of 10% aqueous solution of hydrogen bonding compound-1 (tri (4-t-butylphenyl) phosphine oxide) and modified polyvinyl alcohol (Kuraray Co., Ltd., Poval MP203). Mix to make a slurry. This slurry was fed with a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 4 hours, and then 0.2 g of benzoisothiazolinone sodium salt Water was added to prepare a hydrogen bonding compound concentration of 25% by mass. This dispersion was heated at 40 ° C. for 1 hour and then further heated at 80 ° C. for 1 hour to obtain a hydrogen bonding compound-1 dispersion. The hydrogen bonding compound particles contained in the hydrogen bonding compound dispersion thus obtained had a median diameter of 0.45 μm and a maximum particle diameter of 1.3 μm or less. The obtained hydrogen bonding compound dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust and stored.
[0341]
5) Preparation of development accelerator dispersion and color tone modifier dispersion
(Preparation of Development Accelerator-1 Dispersion)
10 kg of water was added to 10 kg of a development accelerator-1 and 20 kg of a 10% by weight aqueous solution of modified polyvinyl alcohol (Kuraray Co., Ltd., Poval MP203) and mixed well to obtain a slurry. This slurry was fed with a diaphragm pump and dispersed for 3 hours 30 minutes in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm, and then benzoisothiazolinone sodium salt 0.2 g and water were added so that the concentration of the development accelerator was 20% by mass to obtain a development accelerator-1 dispersion. The development accelerator particles contained in the development accelerator dispersion thus obtained had a median diameter of 0.48 μm and a maximum particle diameter of 1.4 μm or less. The obtained development accelerator dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust and stored.
[0342]
(Solid dispersion of development accelerator-2 and color tone modifier-1)
The solid dispersions of the development accelerator-2 and the color tone modifier-1 were also dispersed by the same method as the development accelerator-1, and 20% by mass and 15% by mass of dispersions were obtained, respectively.
[0343]
6) Preparation of polyhalogen compound dispersion
(Preparation of organic polyhalogen compound-1 dispersion)
10 kg of organic polyhalogen compound-1 (tribromomethanesulfonylbenzene), 10 kg of a 20% by weight aqueous solution of modified polyvinyl alcohol (Poval MP203 manufactured by Kuraray Co., Ltd.), 0.4 kg of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate, 14 kg of water was added and mixed well to make a slurry. This slurry was fed with a diaphragm pump and dispersed for 5 hours in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm. Then, 0.2 g of benzoisothiazolinone sodium salt Water was added to prepare an organic polyhalogen compound concentration of 30% by mass to obtain an organic polyhalogen compound-1 dispersion. The organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained had a median diameter of 0.41 μm and a maximum particle diameter of 2.0 μm or less. The obtained organic polyhalogen compound dispersion was filtered through a polypropylene filter having a pore size of 10.0 μm to remove foreign substances such as dust and stored.
[0344]
(Preparation of organic polyhalogen compound-2 dispersion)
10 kg of an organic polyhalogen compound-2 (N-butyl-3-tribromomethanesulfonylbenzoamide), 20 kg of a 10% by weight aqueous solution of modified polyvinyl alcohol (Poval MP203 manufactured by Kuraray Co., Ltd.), and 20 of sodium triisopropylnaphthalenesulfonate 0.4 kg of a mass% aqueous solution was added and mixed well to obtain a slurry. This slurry was fed with a diaphragm pump and dispersed for 5 hours in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm. Then, 0.2 g of benzoisothiazolinone sodium salt Water was added to adjust the concentration of the organic polyhalogen compound to 30% by mass. This dispersion was heated at 40 ° C. for 5 hours to obtain an organic polyhalogen compound-2 dispersion. The organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained had a median diameter of 0.40 μm and a maximum particle diameter of 1.3 μm or less. The obtained organic polyhalogen compound dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust and stored.
[0345]
7) Preparation of phthalazine compound solution
8 kg of Kuraray Co., Ltd. modified polyvinyl alcohol MP203 is dissolved in 174.57 kg of water, then 3.15 kg of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate and a 70% by weight aqueous solution of phthalazine compound-1 (6-isopropylphthalazine) 14.28 kg was added to prepare a 5 mass% solution of phthalazine compound-1.
[0346]
8) Preparation of mercapto compound
(Preparation of mercapto compound-1 aqueous solution)
7 g of mercapto compound-1 (1- (3-sulfophenyl) -5-mercaptotetrazole sodium salt) was dissolved in 993 g of water to obtain a 0.7% by mass aqueous solution.
[0347]
(Preparation of mercapto compound-2 aqueous solution)
20 g of mercapto compound-2 (1- (3-methylureidophenyl) -5-mercaptotetrazole) was dissolved in 980 g of water to obtain a 2.0 mass% aqueous solution.
[0348]
9) Preparation of pigment-1 dispersion
C.I. Pigment Blue 60 (64 g) and Kao Co., Ltd. (Demol N) 6.4 g were mixed with 250 g of water and mixed well to form a slurry. Prepare 800 g of zirconia beads with an average diameter of 0.5 mm, put them in a vessel together with the slurry, disperse with a disperser (1 / 4G sand grinder mill: manufactured by IMEX Co., Ltd.) for 25 hours, add water to add pigment concentration Was prepared so as to be 5% by mass to obtain a pigment-1 dispersion. The pigment particles contained in the pigment dispersion thus obtained had an average particle size of 0.21 μm.
[0349]
10) Preparation of binder liquid
As the binder, each of the polymer latexes of the exemplary compounds (P-1), (P-2), and (P-4) shown in the above synthesis example is 25% by mass NH._FourThe pH was adjusted to 8.35 using OH. Thereafter, the mixture was filtered through a polypropylene filter having a pore size of 1.0 μm to remove foreign substances such as dust and stored, thereby preparing a binder liquid having a solid content concentration of 44 mass%.
In the same manner, other polymer latexes according to the present invention shown in Table 1 were also synthesized to prepare a binder liquid.
[0350]
3-2. Adjustment of coating solution
1) Preparation of image forming layer coating solution-1
1000 g of the fatty acid silver dispersion obtained above, 276 ml of water, pigment-1 dispersion, organic polyhalogen compound-1 dispersion, organic polyhalogen compound-2 dispersion, phthalazine compound-1 solution, binder latex solution (in Table 1) Reducing agent-1 dispersion, reducing agent-2 dispersion, hydrogen bonding compound-1 dispersion, development accelerator-1 dispersion, development accelerator-2 dispersion, color tone modifier-1 dispersion, The aqueous solution of mercapto compound-1 and aqueous solution of mercapto compound-2 were sequentially added, and the silver halide mixed emulsion A was added and mixed well immediately before coating, and the image forming layer coating solution was fed to the coating die as it was and coated.
[0351]
2) Preparation of intermediate layer coating solution
Polyvinyl alcohol PVA-205 (manufactured by Kuraray Co., Ltd.) 1000 g, pigment-1 dispersion 272 g, methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymerization weight ratio 64/9/20/5 / 2) In 4200 ml of latex 19 wt% solution, add 27 ml of 5 wt% aqueous solution of Aerosol OT (American Cyanamid), 135 ml of 20 wt% aqueous solution of diammonium phthalate, so that the total amount is 10000 g. In addition, adjust to pH 7.5 with NaOH to make the intermediate layer coating solution, 9.1 ml / m²Then, the solution was fed to the coating die.
The viscosity of the coating solution was 58 [mPa · s] when measured with a B-type viscometer at 40 ° C. (No. 1 rotor, 60 rpm).
[0352]
3) Preparation of surface protective layer first layer coating solution
64 g of inert gelatin dissolved in water, 112 g of 19.0% by weight latex of methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymerization weight ratio 64/9/20/5/2), phthalic acid 30 ml of 15 mass% methanol solution, 23 ml of 10 mass% aqueous solution of 4-methylphthalic acid, 28 ml of 0.5 mol / L sulfuric acid, 5 ml of 5 mass% aqueous solution of Aerosol OT (American Cyanamid), phenoxyethanol Add 0.5g and 0.1g of benzoisothiazolinone, add water to make a total amount of 750g to make a coating solution, and mix 18.6ml / m of 26% 4% chromium alum mixed with static mixer just before coating.²Then, the solution was fed to the coating die.
The viscosity of the coating solution was 20 [mPa · s] at a B-type viscometer of 40 ° C. (No. 1 rotor, 60 rpm).
[0353]
4) Preparation of surface protective layer second layer coating solution
Inert gelatin 80g dissolved in water, methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymerization weight ratio 64/9/20/5/2) latex 27.5 mass% liquid 102g, fluorine-based 5.4 ml of 2% by weight solution of surfactant (F-1), 5.4 ml of 2% by weight aqueous solution of fluorosurfactant (F-2), 5% of aerosol OT (manufactured by American Cyanamid) % Solution 23ml, polymethyl methacrylate fine particles (average particle size 0.7μm) 4g, polymethyl methacrylate fine particles (average particle size 4.5μm) 21g, 4-methylphthalic acid 1.6g, phthalic acid 4.8g, 0.5mol / L sulfuric acid Water was added to 44 ml of benzoisothiazolinone to a total amount of 650 g, and 445 ml of an aqueous solution containing 4% by weight chromium alum and 0.67% by weight phthalic acid was mixed with a static mixer immediately before coating. Protective layer 8.3ml / m as coating solution²Then, the solution was fed to the coating die.
The viscosity of the coating solution was 19 [mPa · s] at a B-type viscometer of 40 ° C. (No. 1 rotor, 60 rpm).
[0354]
3-3. Preparation of photothermographic material
A photothermographic material sample was applied simultaneously on the surface opposite to the back surface by the slide bead coating method in the order of the image forming layer, the intermediate layer, the first surface protective layer, and the second surface protective layer from the undercoat surface. It was created. At this time, the image forming layer and the intermediate layer were adjusted to 31 ° C., the first surface protective layer was adjusted to 36 ° C., and the second surface protective layer was adjusted to 37 ° C.
[0355]
[Table 1]
[0356]
Coating amount of each compound in the image forming layer (g / m²) Is as follows.
Silver behenate 5.27
Pigment (C.I.Pigment Blue 60) 0.036
Polyhalogen compound-1 0.09
Polyhalogen compound-2 0.14
Phthalazine Compound-1 0.18
Polymer latex (described in Table 1) 9.43
Reducing agent-1 0.55
Reducing agent-2 0.22
Hydrogen bonding compound-1 0.28
Development accelerator-1 0.025
Development accelerator-2 0.020
Color tone adjusting agent-1 0.008
Mercapto Compound-1 0.002
Mercapto compound-2 0.006
Silver halide (as Ag) 0.046
[0357]
The coating and drying conditions are as follows.
The support was neutralized with ion wind before coating, and coating was performed at a speed of 160 m / min. The coating and drying conditions were adjusted within the following ranges for each sample, and were set to conditions that would provide the most stable surface shape.
The gap between the coating die tip and the support is 0.10 to 0.30 mm.
The pressure in the decompression chamber is set to 196 to 882 Pa lower than the atmospheric pressure.
In the subsequent chilling zone, the coating solution is cooled with wind at a dry bulb temperature of 10 to 20 ° C.
It is transported in a non-contact manner and dried with a dry air having a dry bulb temperature of 23 to 45 ° C. and a wet bulb temperature of 15 to 21 ° C. in a helical contactless dryer.
After drying, adjust the humidity at 25 ℃ and humidity 40-60% RH.
Subsequently, the film surface was heated to 70 to 90 ° C., and after the heating, the film surface was cooled to 25 ° C.
[0358]
The photothermographic material thus prepared had a Beck smoothness of 550 seconds on the photosensitive layer surface side and 130 seconds on the back surface. Further, the pH of the film surface on the photosensitive layer surface side was measured and found to be 6.0.
[0359]
The chemical structures of the compounds used in the examples of the present invention are shown below.
[0360]
Embedded image
[0361]
Embedded image
[0362]
Embedded image
[0363]
Embedded image
[0364]
4). Evaluation of photographic performance
4-1. Preparation
The obtained sample was cut into half-cut sizes, packaged in the following packaging materials in an environment of 25 ° C. and 50% RH, stored at room temperature for 2 weeks, and then evaluated as follows.
(Packaging material)
PET 10μm / PE 12μm / Aluminum foil 9μm / Ny 15μm / Polyethylene 50% m containing 3% carbon
Oxygen permeability: 0.02ml / atm · m²・ 25 ℃ ・ day, moisture permeability: 0.10g / atm ・ m²・ 25 ℃ ・ day.
[0365]
4-2. Exposure and heat development
As a sample, an NLHV3000E semiconductor laser manufactured by Nichia Chemical Co., Ltd. was mounted as a semiconductor laser light source on the exposure part of Fuji Medical Dry Laser Imager FM-DPL, and the beam diameter was reduced to 100 μm. The illuminance on the photosensitive material surface of the laser beam is 0 and 1 mW / mm2 to 1000 mW / mm²Vary between 10^-6Exposure was performed in seconds. The oscillation wavelength of the laser beam was 405 nm. In the heat development, four panel heaters were set to 112 ° C.-118 ° C.-120 ° C.-120 ° C., and the development was carried out so that the conveyance speed was increased to a total of 14 seconds. The obtained image was evaluated with a densitometer.
[0366]
4-3. Evaluation item
(1) Fog
The optical density of the unexposed area was measured in Macbeth density form.
(2) Evaluation of sensitivity
The logarithm of the reciprocal of the laser output giving the optical density of the image of 3.2 was obtained and expressed as the difference from the sample No. 1. The laser output value giving an optical density of 3.2 for sample No. 1 was 15 mW.
(3) Maximum density (Dmax)
The optical density saturated by increasing the exposure amount was defined as Dmax.
[0367]
The results are shown in Table 1. The sample of the present invention has sufficient sensitivity that can be drawn by exposure with the semiconductor laser, has low fog, and gives an image with high optical density.
[0368]
Example 2
The effect of the present invention was compared with polymer latexes other than the present invention.
[0369]
(Preparation of comparative polymer latex)
As a comparative polymer latex, an SBR latex was prepared as follows.
In a polymerization kettle of a gas monomer reactor (TAS-2J type manufactured by Pressure Glass Industrial Co., Ltd.), 287 g of distilled water and a surfactant (Pionin A-43-S (manufactured by Takemoto Yushi Co., Ltd.)): solid content 48.5 %) 7.73 g, 1 mol / liter NaOH 14.06 ml, ethylenediaminetetraacetic acid tetrasodium salt 0.15 g, styrene 255 g, acrylic acid 11.25 g, tert-dodecyl mercaptan 3.0 g, the reaction vessel was sealed and the stirring speed was 200 rpm. Stir with. After degassing with a vacuum pump and repeating nitrogen gas replacement several times, 108.75 g of 1,3-butadiene was injected to raise the internal temperature to 60 ° C. A solution obtained by dissolving 1.875 g of ammonium persulfate in 50 ml of water was added thereto, and the mixture was stirred as it was for 5 hours. The mixture was further heated to 90 ° C. and stirred for 3 hours. After the reaction was completed, the internal temperature was lowered to room temperature, and then 1 mol / liter NaOH and NH._FourNa with OH⁺Ion: NH_Four ⁺The addition treatment was performed so that the ion was 1: 5.3 (molar ratio), and the pH was adjusted to 8.4. Thereafter, the mixture was filtered through a polypropylene filter having a pore size of 1.0 μm to remove foreign substances such as dust and stored to obtain 774.7 g of SBR latex. When the halogen ions were measured by ion chromatography, the chloride ion concentration was 3 ppm. As a result of measuring the concentration of the chelating agent by high performance liquid chromatography, it was 145 ppm.
[0370]
The latex has an average particle size of 90 nm, Tg = 17 ° C., solid content concentration of 44% by mass, equilibrium water content of 0.6% by mass at 25 ° C. and 60% RH, and ionic conductivity of 4.80 mS / cm. Using a conductivity meter CM-30S manufactured by Kogyo Co., Ltd., measuring latex stock solution (44% by mass) at 25 ° C.), pH 8.4
[0371]
(Sample preparation)
In Sample 1 of Example 1, Samples 21 to 24 in which only the addition amount of the organic polyhalogen compound was changed as shown in Table 2 were prepared.
In Sample 1 of Example 1, Comparative Samples 25 to 28 were prepared using the comparative polymer latex as the image forming layer binder and changing the addition amount of the organic polyhalogen compound as shown in Table 2.
[0372]
[Table 2]
[0373]
(Performance evaluation)
The photographic performance was evaluated in the same manner as in Example 1.
In addition, the following image storage stability was evaluated.
(1) Evaluation of image storage stability-1
For evaluation of image storage stability, the image recording material after heat development was stored for 10 days under the conditions of 60 ° C. and relative humidity of 40%, and the density change (ΔDmin) of the white background before and after that was measured.
(2) Evaluation of image storage stability-2
<Evaluation of the dark fog after the physiological saline is attached>
The image-recording material after heat development is immersed in physiological saline for 1 minute, dried and stored for 4 days under conditions of 60 ° C. and relative humidity 40%, and the density change (ΔDmin) of the white background before and after that is stored. It was measured.
[0374]
The results are shown in Table 3.
As is clear from the table, it was found that the sample of the present invention had a relatively small amount of organic polyhalogen compound added, high sensitivity, and excellent image storability.
[0375]
[Table 3]
[0376]
【The invention's effect】
According to the present invention, a photothermographic material having high sensitivity and excellent image storability is provided.

Claims (21)

In a photothermographic material containing a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent, and a binder on the same surface of a support, the photosensitive silver halide has a grain in the absence of the organic silver salt. The photosensitive silver halide has a silver iodide content of 80 mol% or more and 100 mol% or less, and the monomer represented by the following general formula (M) is 10 mass% or more as the binder. A photothermographic material comprising a polymer latex obtained by copolymerizing 70% by mass or less and a monomer having an acid group by 1% by mass or more and 20% by mass or less .
General formula (M)
CH ₂ = CR ⁰¹ -CR ⁰² = CH ₂
Wherein, R ⁰¹ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a halogen atom, a cyano group, R ⁰² is to Table alkyl group having 1 to 6 carbon atoms, a halogen atom, a cyano group. 2. The photothermographic material according to claim 1, wherein the silver iodide content of the photosensitive silver halide is 90 mol% or more and 100 mol% or less.   3. The photothermographic material according to claim 1, wherein an average grain size of the photosensitive silver halide is from 5 nm to 80 nm.   3. The photothermographic material according to claim 1, wherein an average grain size of the photosensitive silver halide is from 5 nm to 40 nm. In the general formula (M), a R ⁰¹ is a hydrogen atom, photothermographic material according to any one of claims 1 to 4, wherein R ⁰² is a methyl group. The photothermographic material according to any one of claims 1 claim 5, wherein said polymer latex is a polymer latex obtained by copolymerizing 10 mass% 1 mass% or more of a monomer having an acid group . The photothermographic material according to any one of claims 1 to 6 having a glass transition temperature of the polymer latex, characterized in that it is a -30 ° C. to 70 ° C.. The photothermographic material according to any one of claims 1 to 7, the glass transition temperature of the polymer latex, characterized in that it is a -10 ° C. to 35 ° C.. The photothermographic material according to any one of claims 1 to 8, wherein the polymer latex contains a latex solution per halogen ion 500ppm or less. The photothermographic material according to any one of claims 1 to 9, characterized in that a copolymer latex of a monomer having an acid group - said polymer latex is a styrene - isoprene. The photothermographic material according to any one of claims 1 to 10 wherein said reducing agent is a compound represented by the following general formula (R).
General formula (R)
In the general formula (R), R ¹¹ and R ¹¹ ′ each independently represents an alkyl group having 1 to 20 carbon atoms. R ¹² and R ¹² ′ each independently represent a hydrogen atom or a substituent that can be substituted on a benzene ring. L represents a —S— group or a —CHR ¹³ — group. R ¹³ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. X ¹ and X ¹ ′ each independently represent a hydrogen atom or a group that can be substituted on a benzene ring. In the reducing agent represented by the general formula (R), according to claim 11, wherein R ¹¹ and R ¹¹ 'each represent are each independently a secondary or tertiary alkyl group having 3 to 15 carbon atoms Photothermographic material. The photothermographic material according to any one of claims 1 to 12, characterized in that it contains a development accelerator. The photothermographic material according to claim 13 , comprising a compound represented by the following general formula (A-1) as the development accelerator.
Formula (A-1)
Q ₁ -NHNH-Q ₂
(Wherein Q ₁ represents an aromatic group or a heterocyclic group bonded to —NHNH—Q ₂ at a carbon atom, and Q ₂ represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, Or represents a sulfamoyl group.) The photothermographic material according to claim 13 , comprising a compound represented by the following general formula (A-2) as the development accelerator.
Formula (A-2)
In the general formula (A-2), R ₁ represents an alkyl group, an acyl group, an acylamino group, a sulfonamide group, an alkoxycarbonyl group, or a carbamoyl group. R ₂ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, an acyloxy group, or a carbonate group. R ₃ and R ₄ each represents a group that can be substituted on the benzene ring mentioned in the example of the substituent of formula (A-1). R ₃ and R ₄ may be connected to each other to form a condensed ring. The photothermographic material according to any one of claims 1 to 15, characterized in that it contains an organic polyhalogen compound as antifoggants. The photothermographic material according to claim 16 , wherein the organic polyhalogen compound is a compound represented by the following general formula (H).
General formula (H)
Q- (Y) n-C (Z ₁ ) (Z ₂ ) X
In the formula, Q represents an alkyl group, an aryl group or a heterocyclic group, Y represents a divalent linking group, n represents 0 or 1, Z ₁ and Z ₂ represent a halogen atom, and X represents a hydrogen atom. Or represents an electron withdrawing group. The photothermographic as claimed in any one of claims 1 to 17, one-electron oxidant formed by one-electron oxidation is characterized by containing a compound capable of releasing one or more electrons material. 19. The photothermographic material according to claim 1, wherein the photothermographic material is subjected to laser exposure. 20. The photothermographic material according to claim 19 , wherein the laser is a semiconductor laser. 21. The photothermographic material according to claim 20 , wherein the semiconductor laser has an emission peak intensity at 350 nm to 440 nm and an illuminance of 1 mW / mm < ² > or more.