JP2003330143A - Heat-developable photographic sensitive material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-developable photographic sensitive material having improved moisture resistance. <P>SOLUTION: The heat-developable photographic sensitive material comprises organic silver salt grains, silver halide grains, a nucleus forming agent and a reducing agent on a support and comprises at least one selected from alkyl phthalyl alkyl glycolates, phosphoric esters, phthalic esters, citric esters, compounds represented by the formula R-OOC(CH<SB>2</SB>)<SB>n</SB>COO-R and compounds represented by formula (2). <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material, and more particularly to a photothermographic material having improved humidity resistance.

[0002]

2. Description of the Related Art There are many known photosensitive materials which have a photosensitive layer on a support and which form an image by imagewise exposure. Among them, as a system capable of simplifying environmental protection and image forming means, there is a technique of forming an image by thermal development.

In recent years, in the field of photolithography, it has been strongly desired to reduce the amount of processing waste liquid from the viewpoint of environmental protection and space saving.
Therefore, there is a need for a technology relating to a photothermographic material for photolithography, which can be efficiently exposed by a laser scanner or a laser imagesetter and can form a clear black image having high resolution and sharpness. It is said that. With these heat-developable photosensitive materials, it is possible to supply a customer with a heat-development processing system which eliminates the use of solution-type processing chemicals and is simpler and does not damage the environment.

A method of forming an image by heat development is disclosed in, for example, US Pat. Nos. 3,152,904 and 3,457,0.
75, and D.I. Morgan and B.M. "Thermal Processed Si System by Shely"
Lever Systems A ”(Imaging Processes and Materials (Imaging)
Processes and Materials) Ne
blette 8th edition, Sturge,
V. Wallworth, A. Edited by Shepp, p. 2, 1969).

Such a light-sensitive material comprises a reducible non-photosensitive silver source (for example, an organic silver salt), a catalytically active amount of a photocatalyst (for example, silver halide), and a silver reducing agent, usually an organic binder matrix. It is contained in a dispersed state. The photosensitive material is stable at room temperature, but when it is heated to a high temperature (for example, 80 ° C. or higher) after exposure, it undergoes a redox reaction between a reducible silver source (which functions as an oxidant) and a reducing agent. To generate. This redox reaction is promoted by the catalytic action of the latent image generated by exposure. The silver produced by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas and forms the image.

When the heat-developable photographic light-sensitive material is stored in the low humidity season in winter, there is a problem that the amount of water in the light-sensitive material is reduced and the development reaction is difficult to proceed so that the density is low. As a conventional technique, there is known a technique of reducing the influence of humidity by undercoating vinylidene chloride, but there is an environmental problem. Further, techniques for thickening the protective layer and changing the drying temperature are also known, but they are insufficient.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photothermographic material having improved humidity resistance.

[0008]

The above objects of the present invention have been achieved by the following constitutions.

1. A photothermographic material comprising an organic silver salt grain, a silver halide grain, a nucleating agent, a reducing agent and an alkylphthalylalkyl glycolate on a support.

2. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and a phosphoric acid ester on a support.

3. A photothermographic material comprising a support, which contains organic silver salt particles, silver halide particles, a nucleating agent, a reducing agent, and a phthalate ester.

4. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and a citric acid ester on a support.

5. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and a compound represented by the general formula (1) on a support. .

6. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and a compound represented by the general formula (2) on a support. .

The present invention will be described in more detail. The alkylphthalylalkyl glycolate contained in the heat-developable photographic light-sensitive material (also referred to as light-sensitive material) of the present invention is preferably an alkyl group having 1 to 8 carbon atoms. Examples of the alkyl phthalyl alkyl glycolate include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate,
Propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, propyl phthalyl ethyl glycolate,
Methyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycolate, butyl phthalyl propyl glycolate, methyl Phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl methyl glycolate, octyl phthalyl ethyl glycolate, etc. can be mentioned, and methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl Propyl glycolate, butylphthalyl butyl glycolate,
Octyl phthalyl octyl glycolate is preferable, and ethyl phthalyl ethyl glycolate is particularly preferably used. Also, two or more of these alkylphthalylalkyl glycolates may be mixed and used.

Examples of the phosphoric acid ester which can be used in the present invention include triphenyl phosphate, tricresyl phosphate, phenyldiphenyl phosphate and the like. Examples of the phthalic acid ester include dimethyl phthalate, diethyl phosphate, dioctyl phthalate and diethyl hexyl phthalate. On the other hand, examples of the citric acid ester include acetyl triethyl citrate and acetyl tributyl citrate.

Examples of the compound represented by the above general formula (1) of the present invention include bis (2-ethylhexyl) azelate, bis (2-ethylhexyl adipate), diisononyl adipate, di-n-hexyl adipate, Di-n-octyl adipate, di-n-decyl adipate, diisodecyl adipate, diisobutyl adipate, dibutyl adipate, dibutyl sebacate, bis (2) sebacate
-Ethylhexyl), bis (2-ethylhexyl) dodecanedioate, and the like.

Examples of the compound represented by the above general formula (2) of the present invention include tris (2-ethylhexyl) trimellitate.

The organic silver salt contained in the photosensitive layer of the photothermographic material of the present invention is a reducible silver source, and a silver salt of an organic acid or a heteroorganic acid containing a reducible silver ion source, Particularly preferred are long-chain (10 to 30, preferably 5 to 25 carbon atoms) aliphatic carboxylic acids and nitrogen-containing heterocyclic carboxylic acids. Also useful are organic or inorganic silver salt complexes in which the ligand has a total stability constant for silver ions of 4.0 to 10.0. An example of a suitable silver salt is Research D
isclosure (RD) No. 17029 and 29
963 and include the following: salts of organic acids (eg, gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, lauric acid, etc.); silver carboxyalkyl thiourea salts (eg, , 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl)
-3,3-Dimethylthiourea); a silver complex of a polymer reaction product of an aldehyde and a hydroxy-substituted aromatic carboxylic acid (for example, formaldehyde, acetaldehyde,
Aldehydes such as butyraldehyde and salicylic acid,
Hydroxy-substituted acids such as benzylic acid 3,5-dihydroxybenzoic acid and 5,5-thiodisalicylic acid); silver salts or complexes of thiones (eg, 3- (2-carboxyethyl) -4-hydroxymethyl-4) -Thiazoline-2-thione and 3-carboxymethyl-4-methyl-4-thiazoline-2-thione); imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole, 3-amino-5-benzylthio. Examples thereof include complexes or salts of nitric acid and silver selected from -1,2,4-triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; silver salts of mercaptides. The preferred silver source is silver behenate, silver arachidate or silver stearate.

The organic silver salt can be obtained by mixing a water-soluble silver compound and a compound which forms a complex with silver, and it is described in the forward mixing method, the reverse mixing method, the simultaneous mixing method and JP-A-9-127643. The controlled double jet method described above is preferably used. For example, by adding an alkali metal salt (for example, sodium hydroxide, potassium hydroxide, etc.) to an organic acid, an organic acid alkali metal salt soap (for example,
Sodium behenate, sodium arachidate, etc.), and then controlled double jet
Crystals of an organic silver salt are prepared by adding the soap and silver nitrate. At that time, silver halide grains may be mixed.

The silver halide grains contained in the photosensitive layer of the photothermographic material of the present invention function as an optical sensor. In the present invention, the average particle size is preferably small in order to suppress white turbidity after image formation and to obtain good image quality, and the average particle size is preferably 0.03 μm or less, more preferably 0.01 to 0.
It is in the range of 03 μm. The silver halide grains of the heat-developable photographic material of the present invention are produced at the same time when the organic silver salt is prepared, or when the organic silver salt is prepared by mixing the silver halide grains. It is preferable that silver halide grains are formed in a state of being fused with a silver salt to form fine grains, so-called in situ silver. The method for measuring the average grain size of the silver halide grains is carried out by photographing with an electron microscope at a magnification of 50,000, measuring the long side and the short side of each silver halide grain, measuring 100 grains, and averaging them. The average particle size is determined.

The term "grain size" as used herein means the length of the edges of silver halide grains when the silver halide grains are cubic or octahedral so-called normal crystals. Further, in the case of not a normal crystal, for example, in the case of spherical, rod-shaped or tabular grains, it means the diameter when considering a sphere equivalent to the volume of silver halide grains. The silver halide grains are preferably monodisperse. The monodispersion as used herein means that the monodispersity calculated by the following formula is 40% or less. The particles are more preferably 30% or less, and particularly preferably 0.1 to 20%.

Monodispersity = (standard deviation of grain size) / (average value of grain size) × 100 In the present invention, silver halide grains have a mean grain size of 0.01.
.About.0.03 .mu.m, and more preferably monodisperse particles, and the graininess of the image is also improved by setting it in this range.

The shape of the silver halide grains is not particularly limited, but it is preferable that the ratio of Miller index [100] faces is high, and the ratio is 50% or more, and further 7%.
It is preferably 0% or more, and particularly preferably 80% or more. The ratio of the Miller index [100] plane is determined by T.W., which utilizes the adsorption dependence of the [111] plane and the [100] plane in the adsorption of the sensitizing dye. Tani; J. Imaging Sci. , 29,
165 (1985).

Another preferred silver halide grain shape is a tabular grain. The tabular grains referred to herein mean those having an aspect ratio = r / h of 3 or more when the square root of the projected area is the particle size rμm and the thickness in the vertical direction is hμm. Among them, the aspect ratio is preferably 3 or more and 50 or less. The particle size is preferably 0.03 μm or less, more preferably 0.01 to 0.03 μm. These manufacturing methods are described in US Pat. No. 5,264,337,
No. 5,314,798, No. 5,320,958, etc., and the desired tabular grains can be easily obtained. When these tabular grains are used in the present invention, the sharpness of the image is further improved.

The composition of the silver halide grains is not particularly limited and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide and silver iodide. The photographic emulsion used in the present invention is described in P. Chimie by Glafkides
et Physique Photographiqu
e (Paul Montel, 1967), G.E.
F. Duffin Photographic Em
ulsion Chemistry (The Foca
I Press, 1966), V.I. L. Zelik
Manning et Coat by Making and Coat
ing Photographic Emulsion
(The Focal Press, 1964) and the like.

The silver halide grains used in the present invention preferably contain an ion or a complex ion of a metal belonging to Groups 6 to 10 of the Periodic Table of the Elements for the purpose of improving the illuminance failure and adjusting. Examples of the above metals include W and F
e, Co, Ni, Cu, Ru, Rh, Pd, Re, O
s, Ir, Pt, and Au are preferable.

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

The silver halide grains in the present invention are preferably chemically sensitized. Preferred chemical sensitization methods include sulfur sensitization, as is well known in the art.
A selenium sensitization method, a tellurium sensitization method, a noble metal sensitization method such as a gold compound, platinum, palladium, or an iridium compound, or a reduction sensitization method can be used.

In the present invention, in order to prevent devitrification of the photothermographic material, the total amount of silver halide grains and organic silver salt is 0.3 to 2.2 g per m ² in terms of silver amount. , 0.5 to 1.5 g is more preferable. Within this range, a high contrast image can be obtained. The amount of silver halide based on the total amount of silver is 50% or less by mass ratio, preferably 25%.
% Or less, more preferably 0.1 to 15%.

The silver halide grains used in the present invention are 350
It has a maximum absorption of light in the range of up to 450 μm and does not need to have a sensitizing dye in particular, but it may be contained if necessary.

Examples of suitable reducing agents contained in the photosensitive layer or protective layer of the heat-developable photographic light-sensitive material of the present invention are described in US Pat. Nos. 3,770,448, 3,773,512, and US Pat. Each specification such as No. 3,593,863 and RD No. 170
29 and 29963, and includes the following.

Aminohydroxycycloalkenone compounds (eg, 2-hydroxy-3-piperidino-2-cyclohexenone); aminoreductones (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents N-hydroxyurea derivatives (for example, N-p-methylphenyl-N-hydroxyurea); aldehyde or ketone hydrazones (for example, anthracene aldehyde phenylhydrazone); phosphoramide phenols; phosphoramide anilines; Hydroxybenzenes (eg hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5-dihydroxy-phenyl) methylsulfone); Sulfhydroxamic acids (eg benzenes Fuhydroxamic acid); sulfonamide anilines (for example, 4- (N-methanesulfonamido) aniline); 2-tetrazolyl thiohydroquinones (for example, 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone ); Tetrahydroquinoxalines (eg, 1,2,3,4-tetrahydroquinoxaline); Amidooximes; Aazines; Aliphatic carboxylic acid aryl hydrazides and ascorbic acid combination; Polyhydroxybenzene and hydroxylamine combination; Reductone and / or hydrazine; hydroxanoic acids; combination of azines and sulfonamide phenols; α-cyanophenylacetic acid derivative; bis-β
-A combination of naphthol and a 1,3-dihydroxybenzene derivative; 5-pyrazolones; a sulfonamidephenol reducing agent; 2-phenylindane-1,3-dione and the like; chroman; 1,4-dihydropyridines (for example,
2,6-dimethoxy-3,5-dicarbethoxy-1,
4-dihydropyridine); bisphenols (for example,
Bis (2-hydroxy-3-t-butyl-5-methylphenyl) methane, bis (6-hydroxy-m-tri) mesitol, 2,2-bis (4-hydroxy-3-methylphenyl) propane , 4,4-ethylidene-bis (2-t-butyl-6-methylphenol)), a UV-sensitive ascorbic acid derivative; hindered phenols; 3-pyrazolidones. Among them, particularly preferable reducing agents are hindered phenols.

The amount of reducing agent used is preferably 1 × 10 ^-2 to 10 mol, and particularly 1 × 10 ^{-2 to} 1.5 mol, per mol of silver.

A hardening agent may be used in the photosensitive layer of the heat-developable photographic material of the present invention, and as a hydrazine compound as a hardening agent, RD 23515 (November 1983).
Monthly issue, P. 346) and documents cited therein, as well as U.S. Pat. Nos. 4,080,207 and 4,269,92.
No. 9, No. 4,276, 364, No. 4, 278, 7
No. 48, No. 4,385, 108, No. 4,459,
No. 347, No. 4,478,928, No. 4,56.
No. 0,638, No. 4,686,167, No. 4,9
12,016, 4,988,604, 4,
994, 365, 5,041,355, 5,104,769, British Patent 2,011,391.
B, European Patent Nos. 217,310 and 301,79
9, No. 356,898, JP-A-60-17973.
No. 4, No. 61-170733, No. 61-270744.
No. 62-178246 and No. 62-270948.
No. 63, No. 63-29751, No. 63-32538, No. 63-104047, No. 63-121838, No. 6
3-129337, 63-223744, 63
-234244, 63-234245, 63-
234246, 63-294552, 63-3
06438, 64-10233 and JP-A-1-90.
No. 439, No. 1-100530, No. 1-105941
No. 1, No. 1-105943, No. 1-276128, No. 1-280747, No. 1-283548, No. 1-2.
83549, 1-285940, 2-2541.
No. 2, No. 2-77057, No. 2-139538, No. 2
-196234, 2-196235, 2-19
No. 8440, No. 2-198441, No. 2-19844
No. 2, No. 2-220042, No. 2-221953,
2-221954, 2-285342, 2-
285343, 2-289843, 2-302
No. 750, No. 2-304550, No. 3-37642
No. 3, No. 3-54549, No. 3-125134, No. 3
-184039, 3-240036, 3-24
No. 0037, No. 3-259240, No. 3-28003
No. 8, No. 3-228536, No. 4-51143, No. 4-56842, No. 4-84134, No. 2-230.
No. 233, No. 4-96053, No. 4-216544.
No. 5, No. 5-45761, No. 5-45762, No. 5-
No. 45763, No. 5-45764, No. 5-45765.
No. 6-289524, No. 9-160164 and the like.

In addition to this, the compound represented by (Chemical formula 1) described in JP-B-6-77138, specifically, the compounds described on pages 3 and 4 of the publication, JP-B-6- 9308
Compounds represented by the general formula (1) described in JP-A No. 2-38, specifically compounds 1 to 38 described on pages 8 to 18 of the same, and the general formula described in JP-A-6-23049. The compounds represented by (4), (5) and (6), specifically the compounds 4-1 to 4- described on pages 25 and 26 of the same publication.
10, Compounds 5-1 to 5-4 described on pages 28 to 36
2, and compounds 6-1 to 6- described on pages 39 and 40
7, compounds represented by formulas (1) and (2) described in JP-A-6-289520, specifically, compounds 1-1) to 1--1 described on pages 5 to 7 of the same. 17) and 2-1), and the compounds represented by (Chemical Formula 2) and (Chemical Formula 3) described in JP-A-6-313936, specifically, the compounds described on pages 6 to 19 of the same, Kaihei 6-313
In the compound represented by (Chemical formula 1) described in Japanese Patent Publication No. 951), specifically, the compounds described on pages 3 to 5 of the same, the compound represented by formula (I) described in JP-A-7-5610. Compounds represented, specifically, compounds I-1 to I-38 described on pages 5 to 10 of the publication and compounds represented by general formula (II) described in JP-A-7-77783. Specifically, the compounds II-1 to II-10 described on pages 10 to 27 of the same publication.
2, compounds represented by formula (H) and formula (Ha) described in JP-A-7-104426, specifically, compounds H-1 to H described on pages 8 to 15 of the same. -4
Those described in No. 4 and the like can be used.

Further, other contrast-increasing agents used in the present invention are the compounds described on pages 33 to 53 of JP-A No. 11-316437, and more preferably JP-A 20.
No. 00-298327, the following general formula (C
Vinyl compounds of 1), general formula (C2) and general formula (C3) are preferably used.

[0038]

[Chemical 2]

In the general formula (C1), R ¹¹ , R ¹² and R ¹³ each independently represent a hydrogen atom or a substituent, and Z
Represents an electron-withdrawing group or a silyl group, R ¹¹ and Z, R ¹² and R
¹³ , and R ¹³ and Z may be bonded to each other to form a cyclic structure.

In the general formula (C2), R ¹⁴ represents a substituent. Further, in the general formula (C3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alcooxy group, an alkylthio group, an alkylamino group, an arylthio group, an anilino group, a heterocyclic oxy group. Represents a group, a heterocyclic thio group or a heterocyclic amino group.
In the general formula 4, X and Y and A and B may be bonded to each other to form a cyclic structure.

Specific compounds of the above general formula (C1), general formula (C2) and general formula (C3) include the following compounds.

[0042]

[Chemical 3]

[0043]

[Chemical 4]

[0044]

[Chemical 5]

[0045]

[Chemical 6]

As described above, in the present invention, at least one of the contrast enhancers is added to the intermediate layer provided between the photosensitive layer and the protective layer.
It is characterized by containing a seed, and if necessary, the contrast-increasing agent can also be contained in the photosensitive layer. The amount of the contrast increasing agent contained in the photothermographic material of the present invention is 1
0.1-0.001 mol is preferable with respect to mol, and 0.1.
05-0.005 mol is more preferable. The amount of the contrast enhancing agent contained in the intermediate layer is preferably 0.005 mol or more.

A photosensitive layer of the photothermographic material of the present invention,
The binder used in the non-photosensitive layer may be either a hydrophilic binder (a binder or latex that dissolves in water) or a hydrophobic binder (a binder that dissolves in an organic solvent), but the binders in each layer are in the same solvent system. It is preferable that the binder is soluble, for example, the binder of each layer of the photosensitive layer, the intermediate layer and the protective layer is an organic solvent-based binder or a hydrophilic binder.

The binder used in each layer is transparent or translucent and generally colorless, and natural polymers, synthetic monopolymers and copolymers, and other substances that serve as a medium for forming a film are used. Specific examples of the binder include: water-soluble binders such as gelatin, gum arabic, poly (vinyl alcohol), hydroxyethyl cellulose, casein, starch, cellulose acetate, cellulose acetate butyrate, poly (vinylpyrrolidone), poly (acrylic). Acid), poly (methylmethacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-
Butadiene), poly (vinyl acetal) s (for example,
Poly (vinyl formal) and poly (vinyl butyral)), poly (ester) s, poly (urethane) s, phenoxy resin, poly (vinylidene chloride), poly (epoxides), poly (carbonates), poly (vinyl acetate) ), Cellulose esters, hydrophobic binders such as poly (amide), preferably polyvinyl butyral,
Hydrophobic binders such as cellulose acetate, cellulose acetate butyrate, polyester, polycarbonate, polyacrylic acid, polyurethane, etc., particularly hydrophobic binders such as polyvinyl butyral, cellulose acetate, cellulose acetate butyrate, polyester, etc., and monomers for those binder resins. Examples thereof include latexes obtained by polymerizing in water by an emulsion polymerization method or a suspension polymerization method.

As the main solvent for dissolving the hydrophobic binder, for example, alcohols (methanol, ethanol, propanol), ketones (acetone, methylethylketone) dimethylformamide, dimethylsulfoxide, methylcellosolve, etc. are preferably used.

In order to control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer is formed on the same side as the photosensitive layer, or an antihalation dye layer on the opposite side, an auxiliary layer such as a so-called backing layer is formed. Alternatively, the photosensitive layer may contain a dye or a pigment. In these auxiliary layers, in addition to binders and matting agents, polysiloxane compounds,
A slip agent such as wax or liquid paraffin may be contained.

Further, in the photothermographic material of the present invention, various surfactants are used as coating aids, and among them, the fluorine-based surfactants improve the charging characteristics or cause spot-like coating failure. It is preferably used for prevention.

The heat-developable photographic light-sensitive material of the present invention may have a plurality of light-sensitive layers, and in order to adjust gradation, the light-sensitive layer may be composed of a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / It may be a high-sensitivity layer.

Examples of suitable toning agents for use in the present invention are disclosed in RD 17029.

An antifoggant may be used in the photothermographic material of the present invention.
It may be added to any of the intermediate layer, the protective layer and other forming layers.

The photothermographic material of the present invention includes, for example,
Surfactants, antioxidants, stabilizers, plasticizers, coating aids and the like may be used. These additives and the above-mentioned other additives are described in RD 17029 (p. 9, June 1978).
To 15) can be preferably used.

The support used in the present invention is a plastic film (for example, polyethylene terephthalate, polycarbonate, polyimide, nylon, cellulose triacetate) in order to obtain a predetermined optical density after development and prevent deformation of the image after development. , Polyethylene naphthalate) are preferred.

Among them, a preferable support is a plastic support containing polyethylene terephthalate and a styrene polymer having a syndiotactic structure. The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm.

It is also possible to use a heat-treated plastic support. The plastics to be adopted include the above-mentioned plastics. The heat treatment of the support means that after the support is formed into a film and before a silver halide photosensitive layer, a non-photosensitive layer, or another forming layer is coated, the temperature is 30 ° C. from the glass transition point of the support. It is preferable to heat at a temperature higher than the above, preferably a temperature higher than 35 ° C, and more preferably a temperature higher than 40 ° C. However, heating to a temperature above the melting point of the support deteriorates the strength uniformity of the support, which is not preferable.

In the present invention, a conductive compound such as a metal oxide or a conductive polymer may be included in the constituent layer in order to improve the charging property. These may be contained in any layer, but are preferably an undercoat layer, a backing layer, a layer between the silver photosensitive layer and the undercoat layer, and the like.

The coating method includes reverse roll, gravure roll, air doctor coater, blade coater, air knife coater, squeeze coater, impregnation coater, wire bar coater, transfer roll coater, kiss coater, cast coater or spray coater, extrusion coater. However, it is more preferable to perform wet-on-wet multi-layer coating with an extrusion-type extrusion coater.

In the multi-layer coating in the wet-on-wet system, since the upper layer is coated while the lower layer is in a wet state, the adhesiveness between the upper and lower layers is improved and the coating is performed once. Since it is finished, the coated surface is less likely to be scratched, and since the smoothness is good, uneven development is less likely to occur, and the yield can be further improved.

[0062]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1 1. Preparation of Subbed PET Support 1 Plasma treatment 1 was applied to both sides of a 125 μm-thick PET film that had been biaxially stretched and heat-set under the following conditions, and then one side was coated with the subbing coating solution a-1. After coating so as to have a film thickness of 0.8 μm, it is dried to form an undercoat layer A-1,
Further, the undercoating coating solution b-1 having the following antistatic treatment on the opposite surface
Was applied to give a dry film thickness of 0.8 μm and then dried to obtain an undercoat layer B-1 as a conductive layer. Next, plasma treatment 2 was applied to the surface of each undercoat layer under the following conditions. << Plasma processing conditions >> Using a batch type atmospheric pressure plasma processing apparatus (AP-I-H-340 manufactured by EC Chemical Co., Ltd.), high frequency output is 4.5 kW, frequency is 5 kHz,
Plasma treatment 1 and plasma treatment 2 were performed with a treatment time of 5 seconds and a volume ratio of argon, nitrogen and hydrogen of 90%, 5% and 5%, respectively, as gas conditions. <Subbing coating liquid a-1> Butyl acrylate (30% by mass) t-Butyl acrylate (20% by mass) Styrene (25% by mass) 2-Hydroxyethyl acrylate (25% by mass) Copolymer latex liquid (solid content 30%) 270 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Polystyrene fine particles (average particle size 3 μm) 0.05 g Colloidal silica (average particle size 90 μm) 0.1 g Finish with water to 1 liter Coating liquid b-1> Tin oxide (average particle size 36 nm doped with 0.1% indium) 0.26 g / m ² amount Butyl acrylate (30 mass%) Styrene (20 mass%) Glycidyl acrylate (40 mass%) ) Copolymer latex liquid (solid content 30%) 270 g Hexamethylene-1,6-bis (ethylene urea) 0 Finishing to 1 liter with 0.8 g of water <Heat treatment of support> In the undercoat drying process of the obtained undercoated support, the support was heated at 140 ° C and then gradually cooled. At that time, it was conveyed with a tension of 1 × 10 ⁵ Pa. 2. Coating of back layer surface side Back layer coating liquid 1 and back protective layer coating liquid 1 having the following compositions
Before being applied, each is filtered using a filter having an absolute filtration accuracy of 20 μm, and then the total wet film thickness is 30 μm on the surface of the antistatically processed undercoat layer B-1 of the support prepared above with an extrusion coater. As described above, simultaneous multilayer coating was performed at a speed of 120 m / min and drying was performed at 60 ° C. for 4 minutes. <Back Layer Coating Liquid 1> Methyl ethyl ketone 16.4 g / m ² Dye A 17 mg / m ² Stabilizer B-1 (Sumitomo Chemical Co., Ltd. Sumilizer BPA) 20 mg / m ² Stabilizer B-2 (Yoshitomi Pharmaceutical Tomisorb 77) 50 mg / m ² cellulose acetate propylate (Eastman Chemical Co. CAP504-0.2) 0.5g / m ² cellulose acetate butyrate (Eastman Chemical Co. C AB381-20) 1.5g / m ²

[0064]

[Chemical 7]

<Back protective layer coating liquid 1> Methyl ethyl ketone 22 g / m ² Antistatic agent; (CH ₃ ) ₃ SiO-[(CH ₃ ) ₂ SiO] ₂ O- [CH ₃ SiO {CH ₂ CH ₂ CH ₂ O _{(CH 2 CH 2 O) 10} (CH 2 CH 2 CH 2 O) 15 CH 3} ] _{3 O- Si (CH 3) 3} 22mg / m 2 fluorine-containing surfactant _{F-1: C 8 F 17} SO 3 Li 10 mg / m ² Cellulose Acetate Propylate (Eastman Chemical Company CAP504-0.2) 0.5 g / m ² Cellulose Acetate Butyrate (Eastman Chemical Company CAB381-20) 1.5 g / m ² Matting Agent (Fuji Devison Company) Syloid 74; silica having an average particle diameter of 7 [mu] m) preparation of 12 mg / m ² (silver halide grains) gelatin 7.5g and bromide of pure water 900ml Temperature by dissolving potassium 10mg 3
After adjusting the pH to 3.0 at 5 ° C, 370 ml of an aqueous solution containing 74 g of silver nitrate, 0.436 mol of potassium bromide and 0.436 mol of potassium iodide in a molar ratio of (96/4), and (NH ₄ ) ₂ RhCl.
Aqueous solution 3 containing ₅ (H ₂ O) 5 × 10 ^-6 mol / liter
While maintaining pAg at 7.7, 70 ml was added over 10 minutes by the controlled double jet method. Then 4-
Hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (0.3 g) was added and the pH was adjusted to 5 with NaOH to obtain an average particle size of 0.06 μm and a projected diameter area variation coefficient of 8%, {100. } Silver halide grains made of cubic silver iodobromide having a face ratio of 86% were obtained. The emulsion was coagulated and precipitated using a gelatin coagulant, desalted, and 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and pAg to 7.5.

(Preparation of organic fatty acid silver emulsion) 300 ml of water
10.6 g of behenic acid was put in it and dissolved by heating at 90 ° C.
1.1 ml was added and left as it was for 1 hour. Thereafter, the mixture was cooled to 30 ° C., and 1 mol / L phosphoric acid 7.
0 ml was added and 0.01 g of N-bromosuccinimide was added with sufficient stirring. Then, the silver halide grains prepared in advance were added to the behenic acid with stirring so that the amount of silver would be 10 mol% as silver, with stirring. Further 1 mol / L silver nitrate aqueous solution 25
ml was continuously added over 2 minutes, and the mixture was left stirring for 1 hour.

Polyvinyl butyral dissolved in ethyl acetate was added to this emulsion, and the mixture was sufficiently stirred and then allowed to stand to separate into an ethyl acetate phase containing silver behenate grains and silver halide grains and an aqueous phase. After removing the aqueous phase, silver behenate particles and silver halide particles were collected by centrifugation. Then, 20 g of synthetic zeolite A-3 (spherical) manufactured by Tosoh Corporation and 22 ml of isopropyl alcohol were added, and the mixture was left for 1 hour and then filtered. Furthermore, 3.4 g of polyvinyl butyral and 23 ml of isopropyl alcohol were added, and the mixture was sufficiently stirred and dispersed at 35 ° C. at high speed to complete the preparation of the organic fatty acid silver emulsion.

(Photosensitive layer composition) Organic fatty acid silver emulsion 1.4 g (in silver) / m ² pyridinium hydrobromide perbromide 1.5 × 10 ⁻⁴ mol / m ² calcium bromide 1.8 × 10 ⁻⁴ mol / m ² 2- (4-chlorobenzoyl) benzoic acid 1.5 × 10 ⁻³ mol / m ² infrared sensitizing dye 1 4.2 × 10 ⁻⁶ mol / m ² 2-mercaptobenzimidazole 3.2 × 10 ^-3 mol / m ² 2-tribromomethylsulfonylquinoline 6.0 × 10 ^-4 mol / m ² 4-methylphthalic acid 1.6 × 10 ^-3 mol / m ² tetrachlorophthalic acid 7.9 × 10 ^-4 mol / m ² 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane 4.8 × 10 ⁻³ mol / m ² Dye B 3 × 10 ⁻⁵ mol / m ² m ² nucleating agent C-65 0.5 × 10 ⁻³ mol / m ² Compound of the present invention Methyl ethyl ketone, acetone, and methanol were appropriately used as the solvents described in Tables 1 to 6.

[0069]

[Chemical 8]

(Surface Protective Layer Composition) A surface protective layer coating solution was prepared as follows.

Cellulose acetate butyrate 4 g / m ² phthalazine 3.2 × 10 ⁻³ mol / m ² matting agent (particle size 2 μm) 50 mg / m ² compound of the present invention Acetone and methanol were used appropriately.

Evaluation of Photographic Performance (Exposure) Beam diameter (FWHM of 1/2 of beam intensity) 12.56 μm for each of the manufactured photothermographic materials
m, laser output 50 mW, single-channel cylindrical inner surface type laser exposure device equipped with a semiconductor laser with an output wavelength of 783 nm, and the rotation speed of the mirror is 60000 rp.
m and the exposure time was 1.2 × 10 ⁻⁸ seconds. The overlap coefficient at this time is 0.449,
Laser energy density on the surface of photothermographic material is 7
It was set to 5 μJ / cm ² .

(Heat Development Treatment) The heat development treatment is 120 ° C. 1
It took 7 seconds.

(Evaluation of Photographic Performance) A heat-developable photographic light-sensitive material was prepared as a sample whose humidity was adjusted at 23 ° C. and 80% for 12 hours and a sample whose humidity was adjusted at 23 ° C. and 20% for 12 hours, and was exposed to a line width of 50 μm in the same environment. Then, heat development processing was performed.

The development humidity dependency was evaluated by measuring the difference in line width after each treatment. Also, Dmin (fog) and Dmax (maximum density) under each environment
Was also evaluated. The density was measured with a Macbeth TD904 densitometer. The evaluation results of each photothermographic material are shown in Tables 1-6.

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

[Table 3]

[0079]

[Table 4]

[0080]

[Table 5]

[0081]

[Table 6]

As is clear from Tables 1 to 6, the samples of the present invention all showed excellent performance for comparison.

[0083]

According to the present invention, a photothermographic material having improved humidity resistance can be provided.

Claims (6)

[Claims] 1. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and an alkylphthalylalkyl glycolate on a support. . 2. A photothermographic material comprising an organic silver salt particle, a silver halide particle, a nucleating agent, a reducing agent and a phosphoric acid ester on a support. 3. A photothermographic material comprising an organic silver salt grain, a silver halide grain, a nucleating agent, a reducing agent and a phthalate ester on a support. 4. A photothermographic material comprising a support, which contains organic silver salt particles, silver halide particles, a nucleating agent, a reducing agent, and a citric acid ester. 5. A support containing organic silver salt particles, silver halide particles, a nucleating agent, and a reducing agent, and a compound represented by the following general formula (1). Photothermographic material. Formula (1) R-OOC (CH 2) in _n COO-R [wherein, R represents an alkyl group having 1 to 10 carbon atoms, n is an integer of 4-10. ] 6. A support containing organic silver salt particles, silver halide particles, a nucleating agent, a reducing agent, and a compound represented by the following general formula (2). Photothermographic material. [Chemical 1] [In the formula, R ₁ represents an alkyl group having 1 to 8 carbon atoms. ]