JP2001242589A - Image recording method using heat developable photosensitive material and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat development recording method in which film peeling immediately after development is prevented and film peeling and scuffing are not caused when a film is hung on a viewing screen and to provide an image forming method. SOLUTION: In the image forming method, a heat developable photosensitive material having a photosensitive layer containing at least (a) an organic silver salt, (b) a photocatalyst, (c) a reducing agent and (d) a binder on the base and further having (e) at least one compound selected from epoxy compounds and an acid anhydrides in combination is heat-developed while leaving a front edge part of <=20 mm unexposed and holding <=500 mg/m2 residual solvent after coating and drying. In the image recording method, the heat developable photosensitive material is exposed using a laser scanning exposure system in such a way that the surface of the photosensitive material to be exposed and scanning laser light do not substantially make right angles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording method and an image forming method using a photothermographic material, and more particularly to an image recording method and an image forming method having excellent stability during heat development.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making and medical treatment, a waste liquid accompanying wet processing of an image forming material has been a problem in terms of workability. There is a strong demand for weight loss.

[0003] Therefore, there is a need for a technique relating to photothermographic materials for photographic technology, which enables efficient exposure with a laser imagesetter or laser imager and can form a high-resolution, clear black image. As this technique, for example, US Pat. Nos. 3,152,904 and 3,457,07
No. 5, and D.E. "Dry Silver Photo Material" by Morgan
Ophthalmic Materials) ", Hand
book of Imaging Material
s, Marcel Dekker Inc. , P. 48 (1991) and the like, a photothermographic material having a photosensitive layer containing an organic silver salt, a photosensitive silver halide, a reducing agent and a binder on a support is known.

However, in these photothermographic materials, since organic silver is converted into a brittle organic acid by development, the film is peeled off from the leading end of the film when it is applied to a shakasten, and the commercial value is significantly reduced.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a heat-development recording method, an image-forming method, which prevents film peeling immediately after development and prevents film peeling and scratching when the film is hung on a shark caster. It is to provide a forming method.

[0006]

The above object of the present invention is achieved by the following means. That is, a photosensitive layer containing at least (a) an organic silver salt, (b) a photocatalyst, (c) a reducing agent and (d) a binder is provided on a support, and (e) an epoxy compound and an acid anhydride. A photothermographic material having a combination of at least one compound selected from the group consisting of:
An image forming method in which heat development is performed in a state where the amount of the residual solvent after drying is 500 mg / m ² or less.

The above component (e) is contained in the photosensitive layer, and the epoxy compound of the component (e) is represented by the general formula (I):
It is preferable that the “chemical formula 1” and the acid anhydride are compounds represented by the general formula (II) “chemical formula 2”.

In addition, the above-mentioned photothermographic material can be used in a laser scanning exposure machine (in particular, a vertical multi laser beam) in which the angle formed by the scanning laser beam and the exposed surface of the photosensitive material does not become substantially perpendicular. An image recording method of exposing using a light emitting device.

Hereinafter, the present invention will be described in more detail. The epoxy compound used in the photothermographic material of the present invention may be any as long as it has at least one epoxy group, and there is no limitation on the number, molecular weight, etc. of the epoxy group. The epoxy group is preferably contained in the molecule as a glycidyl group via an ether bond or an imino bond. The epoxy compound may be any of a monomer, an oligomer and a polymer. The number of epoxy groups present in the molecule is usually about 1 to 10, preferably 2 to 4. When the epoxy compound is a polymer, it may be either a homopolymer or a copolymer, and a particularly preferred range of the number average molecular weight (Mn) is about 2,000 to 20,000.

The epoxy compound used in the present invention is preferably a compound represented by the above general formula (I).

[0011]

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In the formula, R represents an alkylene group which may have a substituent, and X represents a divalent linking group. In the general formula (I), the substituent of the alkylene group represented by R is preferably a group selected from a halogen atom, a hydroxyl group, a hydroxyalkyl group or an amino group. It is preferable that the linking group represented by R has an amide linking moiety, an ether linking moiety, and a thioether linking moiety. The divalent linking group represented by X includes -SO _2- , -SO ₂ NH
-, -S-, -O- or -NR'- and the like are preferable, and R '
Is a monovalent linking group, and is preferably an electron withdrawing group.

Hereinafter, specific examples of the epoxy compound used in the present invention will be shown, but the present invention is not limited to these.

[0014]

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[0015]

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[0016]

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[0017]

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[0018]

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The epoxy compound may be used alone or in combination of two or more, and the content is 1 × 10 ^-6 to 1 × 10 ^6
−2 mol / m ² , more preferably 1 × 1
0 ^-5 to 1 × 10 ^-3 mol / m ² .

The epoxy compound can be added to any layer on the photosensitive layer side of the support, such as a photosensitive layer, a surface protective layer, an intermediate layer, an antihalation layer, and an undercoat layer. Alternatively, it can be added to two or more layers. Also, it can be added to any layer on the opposite side of the support from the photosensitive layer. In the case of a photosensitive material having a photosensitive layer on both surfaces, any layer may be used.

The acid anhydride used in the photothermographic material of the present invention is a compound having at least one acid anhydride group represented by the structural formula -C (= O) -OC (= O)-. .

The acid anhydride used in the present invention is not limited as long as it has at least one acid anhydride group as described above. The number and molecular weight of the acid anhydride group are not limited. The compounds represented are preferred.

[0023]

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In the formula, Z represents an atomic group necessary for forming a monocyclic or polycyclic ring system. In the general formula (II), the monocyclic or polycyclic ring formed by Z may be unsubstituted or substituted. Examples of the substituent include an alkyl group (eg, methyl, ethyl, hexyl), an alkoxy group (eg, methoxy, ethoxy, octyloxy), an aryl group (eg, phenyl, naphthyl, tolyl), a hydroxyl group, and an aryloxy group (eg, phenoxy, tolyloxy). ), An alkylthio group (eg, methylthio, butylthio), an arylthio group (eg, phenylthio), an acyl group (acetyl, propionyl, butyryl,
Benzoyl), a sulfonyl group (eg, methylsulfonyl, phenylsulfonyl), an acylamino group, a sulfonylamino group, an acyloxy group (eg, acetoxy, benzoxy), a carboxyl group, a cyano group, a sulfo group, and an amino group. As the substituent, those not containing a halogen atom are preferable.

Hereinafter, specific examples of the acid anhydride will be shown, but the present invention is not limited thereto.

[0026]

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[0027]

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These acid anhydrides may be used alone or in combination of two or more. Their content is 1 × 10 ^-6 to 1
× 10 ^-2 mol / m ² is preferable, and 1 × 1 is more preferable.
0 ^-5 to 1 × 10 ^-3 mol / m ² .

The acid anhydride can be added to any layer on the photosensitive layer side of the support such as a photosensitive layer, a surface protective layer, an intermediate layer, an antihalation layer, and an undercoat layer. It can be added to one or more layers. Especially, it is preferable to add to the same layer as the epoxy compound of the present invention. or,
In addition, it can be added to any layer on the opposite side of the support from the photosensitive layer. In the case of a photosensitive material having a photosensitive layer on both sides, any layer may be used.

The photothermographic material of the present invention is preferably heat-developed in a state where the residual solvent amount is 500 mg / m ² or less, more preferably 300 mg / m ² or less, and particularly preferably 150 mg / m ² or less. . This will be described in detail later in the preparation of a photothermographic material (application with a solvent).

As the photocatalyst used in the present invention, photosensitive silver halide is preferably used as a photosensor.

In the present invention, the average grain size of the photosensitive silver halide grains is preferably small in order to suppress white turbidity after image formation and to obtain good image quality.
The average particle size is 0.1 μm or less, more preferably 0.1 μm.
It is preferably from 0.1 to 0.1 μm, particularly preferably from 0.02 to 0.08 μm. Here, the particle size refers to the diameter (equivalent circle diameter) of a circle having the same area as an individual particle image observed with an electron microscope. Further, the silver halide is preferably monodispersed. Here, the monodispersion means that the degree of monodispersion obtained by the following equation is 40% or less. The particle size is more preferably 30% or less, and particularly preferably 20% or less.

Monodispersity = (standard deviation of grain size / average of grain size) × 100 The shape of the silver halide grains is not particularly limited, but it is preferable that the proportion occupied by the Miller index [100] plane is high. , This ratio is 50% or more, and even 70%
%, Particularly preferably 80% or more. The ratio of the Miller index [100] plane is [1] in the adsorption of the sensitizing dye.
T.11] utilizing the adsorption dependence of the [100] plane.
Tani; Imaging Sci. , 29,16
5 (1985).

Another preferred form of silver halide is tabular grains. The term "tabular grain" as used herein means that the square root of the projected area of the grain is a particle diameter of r μm, and the vertical thickness is h μm
Means that the aspect ratio = r / h is 3 or more. Among them, the aspect ratio is preferably 3 to 50. Further, the particle size is preferably 0.1 μm or less, more preferably 0.01 to 0.08 μm. These are disclosed in U.S. Patent Nos. 5,264,337 and 5,314,798.
No. 5,320,958, and the like, and intended tabular grains can be easily obtained.

The halogen composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide and silver iodide. Photographic emulsions are described in Glafk
Ides: Chimie et Physique
Photographique (Paul Monte)
l, 1967); F. By Duffin: Ph
autographic Emulsion Chemi
try (published by The Focal Press, 196)
6 years). L. By Zelikman et al: M
aking and Coating Photogr
aphic Emulsion (The Focal
Press, 1964) and the like. That is, any of an acidic method, a neutral method, an ammonia method and the like may be used, and a form in which a soluble silver salt and a soluble halide are reacted may be any of a one-side mixing method, a double-mixing method, a combination thereof and the like. May be used.

The silver halide used in the present invention preferably contains ions of metals belonging to groups 6 to 11 of the periodic table. The above metals include W, Fe, C
o, Ni, Cu, Ru, Rh, Pd, Re, Os, I
r, Pt, and Au are preferable, and among them, Rh, Re, Ru,
It is preferable to be selected from Ir and Os.

The ions of these metals can be introduced into silver halide in the form of metal complexes or complex ions.

In the present invention, the photosensitive silver halide grains may or may not be desalted after grain formation, but when desalting is carried out, it is known in the art such as a noodle method and a flocculation method. Can be desalted by washing with water.

The photosensitive silver halide grains used in the present invention are preferably chemically sensitized. As a preferred chemical sensitization method, a sulfur sensitization method, a selenium sensitization method, and a tellurium sensitization method are well known in the art. In addition, a noble metal sensitization method such as a gold compound, platinum, palladium, or iridium compound or a reduction sensitization method can be applied.

As the compound preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds can be used, and the compounds described in JP-A-7-128768 and the like can be used. it can.

Compounds preferably used in the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, US Pat. No. 2,448,060, British Patent 618, No. 061 or the like can be preferably used.

Specific compounds used in the reduction sensitization method include, as well as ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like. Can be used. Further, reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ions during grain formation.

Next, the organic silver salt used in the present invention will be described. In the organic silver salt used in the present invention, tabular organic silver salt particles having an aspect ratio (average particle diameter / thickness) of 3 to 20 preferably have 60% (number) or more of all organic silver salts. It is more preferably at least 70% (number), particularly preferably at least 80% (number). Further, it is preferable that the number average of the acicular ratio of the tabular organic silver salt particles measured from the main plane direction is 1.1 or more and less than 5.0.

If the aspect ratio is too low, the organic silver salt particles are likely to be densest, and if the aspect ratio is too high, the organic silver salt particles are likely to overlap each other and to be dispersed in a state of being adhered. Therefore, light scattering and the like are likely to occur, and as a result, the transparency of the photosensitive material is likely to be reduced. Therefore, the range described above is considered to be a preferable range.

The tabular organic silver salt particles preferably have an average particle size of 1 μm or less and are monodispersed. The average particle size of the tabular organic silver salt particles is defined as a diameter when a sphere equivalent to the volume of the tabular organic silver salt particles is considered. Average particle size is preferably 0.01-0.8μ
m, particularly preferably 0.05 to 0.5 μm. The monodispersion has the same meaning as in the case of silver halide, and preferably has a monodispersity of 1 to 30.

In the present invention, the organic silver salt has an average particle size of 1
It is more preferable that the particles are monodisperse particles having a particle size of not more than μm.

It is preferable that the tabular organic silver salt particles are preliminarily dispersed together with a binder, a surfactant and the like, if necessary, and then dispersed and pulverized with a media disperser or a high-pressure homogenizer. For the preliminary dispersion, a general stirrer such as an anchor type or a propeller type, a high-speed rotary centrifugal radiation type stirrer (dissolver), and a high-speed rotary shear type stirrer (homomixer) can be used.

As the media dispersing machine, a rolling mill such as a ball mill, a planetary ball mill, and a vibrating ball mill, a bead mill, an attritor, and a basket mill, which are medium stirring mills, can be used, and a high-pressure homogenizer can be used. Various types can be used, such as a type that collides with a wall, a plug, or the like, a type in which liquid is divided into a plurality of pieces and then collides with each other at high speed, and a type in which a thin orifice passes.

Further, in the present invention, it is preferable to have a photosensitive layer containing 0.01 to 0.5 mg of Zr per 1 g of silver, and it is particularly preferable that the photosensitive layer contains 0.01 to 0.5 mg of Zr. This is the case where 3 mg of Zr is contained.

It is very preferable to optimize the binder concentration, the preliminary dispersion method, the operating conditions of the disperser, the number of times of dispersion, and the like, when performing the above dispersion, as a method for obtaining the organic silver salt particles of the present invention.

The organic silver salt used in the present invention is a reducible silver source, and silver salts of organic acids and heteroorganic acids containing a reducible silver ion source, especially long chains (10 to 30, preferably 15 to 30). Aliphatic carboxylic acids having up to 25 carbon atoms) and heterocyclic carboxylic acids having a nitrogen-containing heterocyclic ring are preferably used. 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.

Examples of suitable silver salts include Research D
issues (RD) 17029 and 2996
3 and includes the following:

Salts of organic acids (gallic acid, oxalic acid, behenic acid,
Salts of arachidic acid, stearic acid, palmitic acid, lauric acid and the like); carboxyalkylthiourea salt of silver (1-
(3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc.); silver complexes of polymer reaction products of aldehydes with hydroxy-substituted aromatic carboxylic acids, such as aldehydes (formaldehyde , Acetaldehyde, butyraldehyde, etc.),
Hydroxy-substituted acids (salicylic acid, benzoic acid, 3,5-
Dihydroxybenzoic acid, 5,5-thiodisalicylic acid),
Silver salts or complexes of thiones (3- (2-carboxyethyl) -4-hydroxymethyl-4- (thiazoline-2-
Thione, and 3-carboxymethyl-4-thiazoline-
2-thione), imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole,
A complex or salt of silver and a nitrogen acid selected from 3-amino-5-benzylthio-1,2,4-triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and mercaptides Silver salt.

Preferred silver sources are silver behenate, silver arachidate and / or silver stearate.

The organic silver salt compound can be obtained by mixing a water-soluble silver compound and a compound which forms a complex with silver, but a forward mixing method, a reverse mixing method, a simultaneous mixing method, etc. are preferably used. It is also possible to use a controlled double jet method as described in JP-A-9-127643.

Specifically, an alkali metal salt (sodium hydroxide, potassium hydroxide, etc.) is added to an organic acid to prepare an organic acid alkali metal salt soap (sodium behenate, sodium arachidate, etc.), and then the soap is added. To produce silver salt crystals. At this time, silver halide grains may be mixed, but it is necessary to perform the above series of reaction steps while stirring sufficiently using a suitable stirring member so that the inside of the reaction tank becomes uniform.

The photothermographic material of the present invention contains a reducing agent. Examples of suitable reducing agents are described in US Pat.
70,448, 3,773,512, 3,59
No. 3,863, and RD17029 and 29963, and the following are mentioned. Aminohydroxycycloalkenones, aminoreductone esters as precursors of reducing agents, N-hydroxyurea derivatives,
Hydrazones of aldehydes or ketones, phosphoramidophenols, phosphoramidoanilines, polyhydroxybenzenes, sulfhydroxamic acids, sulfonamidoanilines, 2-tetrazolylthiohydroquinones, tetrahydroquinoxalines, amidooxins, Azines, combinations of polyhydroxybenzene and hydroxylamine, reductone or hydrazine, hydroxanoic acids, combinations of azines and sulfonamidophenols, α-cyanophenylacetic acid derivatives, bis-β-naphthol and 1,3-dihydroxybenzene derivatives Combinations, 5-pyrazolones, sulfonamide phenol reducing agents, 2-phenylindane-1,3-dione, chromans, 1,4-dihydropyridines, bisphenols,
UV-sensitive ascorbic acid derivatives and 3-pyrazolidones.

Among them, particularly preferred reducing agents are hindered phenols. Representative specific examples of preferred hindered phenols are shown below, but are not limited thereto.

[0059]

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[0060]

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The amount of the reducing agent including the above compounds is
Preferably 1 × 10 per mole of silver ^-2-10 mol, especially
Preferably 1 × 10^-2１．５1.5 mol.

The heat-developable photographic material preferably contains an antifoggant. What is known as the most effective antifoggant is mercury ion. The use of a mercury compound as an antifoggant in a light-sensitive material is disclosed in, for example, US Pat. No. 3,589,903. However, the use of mercury compounds is environmentally unfriendly.

As the non-mercury antifoggant, for example, antifoggants such as those disclosed in US Pat. Nos. 4,546,075 and 4,452,885 and JP-A-59-57234 are preferable.

Particularly preferred non-mercury antifoggants are the compounds as disclosed in US Pat. Nos. 3,874,946 and 4,756,999, —C (X ₁ ) (X ₂ )
(X ₃ ) (where X ₁ and X ₂ are each a halogen atom and X ₃
Is a heterocyclic compound having at least one substituent represented by a hydrogen atom or a halogen atom). Examples of suitable antifoggants include compounds described in JP-A-9-288328, paragraphs [0030] to [0036]. Further, as another preferred example of the antifoggant, JP-A-9-90550, paragraph [006]
2 "to" 0063 ". Still other suitable antifoggants are disclosed in US Pat. No. 5,028,5.
No. 23 and European Patent Nos. 600,587 and 605,98.
No. 1, 631, 176 and the like.

It is preferable to add a toning agent to the heat-developable photographic material for the purpose of improving the silver tone after development. Examples of suitable toning agents are disclosed in RD 17029,
There are the following:

Imides, cyclic imides, pyrazoline-5
-Ones, quinazolinones, naphthalimides, cobalt complexes, mercaptans, N- (aminomethyl) aryldicarboximides, blocked pyrazoles, isothiuronium derivatives and certain photobleaching combinations, merocyanine dyes, phthalazinones A phthalazinone derivative or a metal salt of these derivatives, a combination of phthalazinone and a sulfinic acid derivative, a combination of phthalazine + phthalic acid, phthalazine and maleic anhydride, and phthalic acid;
Combination with at least one compound selected from 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivative and anhydride thereof; quinazolinediones, benzoxazine, naloxazine derivative, benzoxazine-2,
4-diones, pyrimidines and asymmetric triazines,
And tetraazapentalene derivatives. Among them, phthalazone or phthalazine is preferred as a color tone agent.

The photothermographic materials include, for example, those described in
No. 159841, No. 60-140335, No. 63-2
No. 31437, No. 63-259651, No. 63-30
Nos. 4242 and 63-15245, U.S. Pat.
9,414, 4,740,455, 4,74
1,966, 4,751,175, 4,83
Sensitizing dyes described in US Pat. No. 5,096 can be used.

Useful sensitizing dyes for use in the present invention are described, for example, in RD17643 IV-A (December, 1978, 23
Pp., 18431 (August, 1979, p. 437), and the like. In particular,
A sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected. For example, JP-A-9-34078, JP-A-9-54409, and JP-A-9-80
No. 679 is preferably used.

A mercapto compound, a disulfide compound, and a thione compound can be contained in order to control development by suppressing or accelerating development, to improve spectral sensitization efficiency, and to improve storage stability before and after development. When a mercapto compound is used in the present invention, any structure may be used, but Ar-SM, Ar-SS-
Those represented by Ar are preferred. Here, M is a hydrogen atom or an alkali metal atom, Ar is one or more nitrogen, sulfur,
Represents an aromatic ring or a condensed aromatic ring having an oxygen, selenium or tellurium atom. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine,
Pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. These heteroaromatic rings include a halogen atom (bromine, chlorine, etc.), a hydroxyl group, an amino group, a carboxyl group, an alkyl group (having one or more carbon atoms, preferably 1 to 4 carbon atoms) and an alkoxy ( One having at least one carbon atom, preferably having 1 to 4 carbon atoms).

Representative examples of mercapto-substituted heteroaromatic compounds include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzothiazole, 3-mercapto-1,2 , 4-triazole, 2-
Mercaptoquinoline, 8-mercaptopurine, 2,3
Examples include, but are not limited to, 5,6-tetrachloro-4-pyridinethiol, 4-hydroxy-2-mercaptopyrimidine, 2-mercapto-4-phenyloxazole, and the like.

It is preferable that the photosensitive layer contains a matting agent, and a matting agent is preferably provided on the surface of the light-sensitive material in order to prevent damage to the image after thermal development. 0.5% by mass relative to all binders on the side
Preferably, it is contained in an amount of about 30%.

The material of the matting agent used may be either an organic substance or an inorganic substance. As inorganic materials, Swiss Patent 3
Silica described in No. 30,158, French Patent 1,29
Glass powder described in US Pat.
Alkaline earth metals or carbonates such as cadmium and zinc described in 3,181 and the like can be used as a matting agent. As organic substances, U.S. Pat.
7, starch derivatives described in Belgian Patent No. 625,451 and British Patent No. 981,198, polyvinyl alcohol described in JP-B-44-3643 and the like;
Polystyrene or polymethacrylate described in Swiss Patent 330,158 and the like, US Patent 3,079,2
Polyacrylonitrile described in No. 57, etc .;
An organic matting agent such as polycarbonate described in JP-A-2,169 or the like can be used.

The shape of the matting agent may be either regular or irregular, but preferably regular and spherical are used. The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a sphere. In the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere.

The matting agent used in the present invention has an average particle size of 0.1.
It is preferably from 5 to 10 μm, more preferably from 1.0 to 8.0 μm. The matting agent has a coefficient of variation of the particle size distribution of preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the variation coefficient of the particle size distribution is a value represented by the following equation. (Standard deviation of particle size / average value of particle size) × 100 The matting agent can be contained in any constituent layer, but is preferably a constituent layer other than the photosensitive layer,
More preferably, it is the outermost layer as viewed from the support. The method of adding the matting agent may be a method in which the matting agent is dispersed in a coating solution in advance, or a method in which the matting agent is sprayed before the drying is completed after the coating solution is applied. When a plurality of types of matting agents are added, both methods may be used in combination.

In the present invention, a conductive compound such as a metal oxide and / or a conductive polymer can be included in the constituent layer in order to improve the chargeability. These may be contained in any of the layers, but preferably include an undercoat layer, a backing layer, and a layer between the photosensitive layer and the undercoat. The conductive compounds described in U.S. Pat. No. 5,244,773, columns 14 to 20 are preferably used.

Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other constituent layers. Surfactants, antioxidants, stabilizers, plasticizers, ultraviolet absorbers, coating aids, and the like may be used in the photothermographic material in addition to those described above. These additives and the other additives mentioned above are Research Disclosure 1702
9 (June 1978, pp. 9-15) can be preferably used.

Binders suitable for the photothermographic material of the present invention are transparent or translucent, generally colorless, and include natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as gelatin, gum arabic, Poly (vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (vinyl methacrylate) ), Copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (poly (vinyl formal) and poly (vinyl butyral), etc.), poly (ester) Kind, poly (urethane ), Phenoxy resins, poly (vinylidene chloride), poly (epoxides), poly (carbonates), poly (vinyl acetate), cellulose esters, and the like poly (amides). It may be hydrophilic or non-hydrophilic.

Further, in order to protect the surface of the light-sensitive material and prevent abrasion, a non-light-sensitive layer can be provided outside the light-sensitive layer. The binder used for these non-photosensitive layers may be the same as or different from the binder used for the photosensitive layers.

In the present invention, in order to increase the speed of thermal development, the amount of binder in the photosensitive layer is 1.5 to 10 g / m 2.
It is preferably ² . More preferably, 1.7 to 8 g
/ M ² .

The support used in the present invention is made of a plastic film (polyethylene terephthalate PET, polycarbonate P) in order to prevent deformation of the image after development processing.
C, polyimide, nylon Ny, cellulose triacetate TAC, polyethylene naphthalate PEN). Among them, a preferred support is PE
Plastics (referred to as SPS) containing T and a styrene-based polymer having a syndiotactic structure can be given.

The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm. Alternatively, a heat-treated plastic support may be used. The plastics to be employed include the above-mentioned plastics.

The heat treatment of the support means that the temperature of the support is higher than the glass transition point (Tg) of the support by at least 30 ° C., preferably 3 ° C., after the formation of the support and before the photosensitive layer is coated.
It is preferable to heat at a temperature higher than 5 ° C, more preferably at a temperature higher than 40 ° C.

Next, the plastic used in the present invention will be described. The photothermographic material of the present invention forms an image by a heat development process, and includes an organic silver salt (reducible silver source), a photocatalyst (photosensitive silver halide), a reducing agent and, if necessary, silver. Toning agents that suppress color tone are usually (organic)
It is contained in a dispersed state in a binder matrix.

The photothermographic material is stable at room temperature, but is developed by heating to a high temperature (for example, 80 to 140 ° C.) after exposure. Heating produces silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. Silver produced by the reaction of the organic silver salt in the exposed areas provides a black image,
This is in contrast to the unexposed areas, where an image is formed. This reaction process proceeds without supplying a processing liquid such as water from the outside.

The photothermographic material of the present invention has at least one photosensitive layer on a support. Although only a photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer on the photosensitive layer.

To control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer on the same side as the photosensitive layer and / or an antihalation dye layer, a so-called backing layer, may be formed on the opposite side. Alternatively, a dye or a pigment may be contained in the photosensitive layer. As the dye to be used, any compound may be used as long as it has a desired absorption in a desired wavelength range, and examples thereof include JP-A-59-6481 and JP-A-59-6481.
No. 182436, U.S. Pat. Nos. 4,271,263 and 4,594,312, European Patent Publication 533,008.
No. 652,473, JP-A-2-216140,
4-348339, 7-191432, 7-
Compounds described in 301890 and the like are preferred.

These non-photosensitive layers preferably contain the binder or matting agent described above, and may further contain a slip agent such as a polysiloxane compound, wax or liquid paraffin.

The light-sensitive layer may be composed of a plurality of layers, and the sensitivity may be changed to a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / high-sensitivity layer for adjusting the gradation.

The details of the photothermographic material are described in, for example, US Pat. Nos. 3,152,904 and 3,457,0
No. 75; Morgan (Dry Silver Pho)
Graphic Material) "and D.C. Morgan and B.A. "The Silver System Treated by Heat (Therma)" by Shelly
llly Processed Silver System
ems) ", Imaging Processes and
Materials (Imaging Processes)
and Materials) Neblette, 8th
Edition, Sturge, V.S. Walworth, A .; It is disclosed in Shepp, 2nd page (1969). Among them, the present invention is characterized in that an image is formed by heat-development of a photosensitive material at 80 to 140 ° C., and no fixing is performed. Therefore, silver halide or organic silver remaining in unexposed areas is characterized. The salt remains in the light-sensitive material without being removed.

In the present invention, after the heat development,
It is preferable that the optical transmission density of the photosensitive material including the support at 00 nm is 0.2 or less. A more preferred value of the optical transmission density is 0.02 to 0.2.

Examples of the solvent used include ketones such as acetone, isophorone, ethyl amyl ketone, methyl ethyl ketone, and methyl isobutyl ketone. Examples of the alcohols include methyl alcohol, ethyl alcohol, propyl alcohol, i-propyl alcohol, butyl alcohol, i-butyl alcohol, diacetone alcohol, cyclohexanol, and benzyl alcohol. Glycols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, hexylene glycol and the like. Examples of ether alcohols include ethylene glycol monomethyl ether (methyl cellosolve), diethylene glycol monoethyl ether, and the like.
Examples of the ethers include ethyl ether, dioxane, i-propyl ether and the like. Examples of the esters include ethyl acetate, butyl acetate, amyl acetate, and i-propyl acetate. As hydrocarbons pentane, hexane, heptane, cyclohexane, benzene, toluene,
Xylene and the like can be mentioned. Methyl chloride as chlorides,
Examples include methylene chloride, chloroform, dichlorobenzene and the like. Examples of the amines include monomethylamine, dimethylamine, triethanolamine, ethylenediamine, and triethylamine. Other examples include water, formamide, dimethylformamide, nitromethane, pyridine, toluidine, tetrahydrofuran, acetic acid and the like. However, it is not limited to these. or,
These solvents can be used alone or in combination of several kinds.

The content (remaining amount) of the solvent in the light-sensitive material can be adjusted by changing conditions such as temperature conditions in a drying step after the coating step. The content of the solvent can be measured by a method using gas chromatography as shown below.

The total amount of the solvent remaining in the photothermographic material of the present invention is preferably 500 mg / m ² or less, more preferably 5 to 400 mg / m ² , and particularly preferably 10 to 300 mg / m ^2. m ² . By adjusting the content of the solvent in the photosensitive material to fall within the above range, a photosensitive material having high sensitivity and low fog density can be obtained after thermal development.

In the present invention, the exposure is preferably performed by laser scanning exposure. However, it is preferable to use a laser scanning exposure machine in which the angle between the exposure surface of the photosensitive material and the scanning laser beam does not become substantially perpendicular. .

Here, "not substantially vertical" means that the angle is most vertical during laser scanning, preferably 55 to 88 degrees, more preferably 60 to 86 degrees.
Degrees, more preferably 65-84 degrees, most preferably 70 degrees.
Say ~ 82 degrees.

The beam spot diameter on the photosensitive material exposed surface when the laser light is scanned on the photosensitive material is preferably 200 μm or less, more preferably 100 μm or less. This is preferable because the smaller the spot diameter is, the less the angle of deviation of the laser incident angle from the vertical can be reduced. Note that the lower limit of the beam spot diameter is 10 μm. By performing such laser scanning exposure, it is possible to reduce image quality deterioration related to reflected light such as occurrence of interference fringe-like unevenness.

The exposure used in the present invention is preferably performed by using a laser scanning exposure machine that emits a scanning laser beam that is a vertical multi. Image quality deterioration such as generation of interference fringe-like unevenness is reduced as compared with the scanning laser beam in the longitudinal single mode. To achieve vertical multiplication, a method such as multiplexing, using return light, or superimposing high frequency is preferable. In addition, the vertical multi means that the exposure wavelength is not single, and the distribution of the exposure wavelength is usually 5 nm or more, preferably 10 nm or more. The upper limit of the exposure wavelength distribution is not particularly limited, but is usually about 60 nm.

[0099]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. In Examples, “%” indicates “% by mass” unless otherwise specified.

Example 1 (Preparation of a support) A corona having a density of 0.170 (measured with a densitometer PDA-65 manufactured by Konica Corporation) and having a thickness of 175 μm and a corona of 8 W / m ² · min. Discharge treatment was performed.

(Preparation of Photosensitive Silver Halide Emulsion a) Water 9
6. Ossein gelatin having an average molecular weight of 100,000 in 00 ml
5 g and 10 mg of potassium bromide were dissolved at a temperature of 35 ° C.
After adjusting the pH to 3.0, 370 ml of an aqueous solution containing 74 g of silver nitrate, potassium bromide and potassium iodide in a molar ratio of (98/2) equimolar to silver nitrate, and iridium chloride in an amount of 1 × 10 ^-4 per mol of silver. 370 ml of an aqueous solution containing
While maintaining the g at 7.7, the mixture was added over 10 minutes by the controlled double jet method. Then 4-hydroxy-6
-Methyl-1,3,3a, 7-tetrazaindene 0.3
g, the pH is adjusted to 5 with sodium hydroxide, the average particle size is 0.06 μm, and the coefficient of variation of the particle size is 12
%, And a (100) face ratio of 87% were obtained. The emulsion was subjected to coagulation sedimentation using a gelatin coagulant and desalting treatment, and then 0.1 g of phenoxyethanol was added.
The pH was adjusted to 5.9 and the pAg was adjusted to 7.5 to obtain a photosensitive silver halide emulsion a.

(Preparation of Powdered Organic Silver Salt A) 111.4 g of behenic acid and 83.8 of arachidic acid were added to 4720 ml of pure water.
g and 54.9 g of stearic acid were dissolved at 80 ° C. Next, while stirring at a high speed, 540.2 ml of a 1.5 mol / L aqueous sodium hydroxide solution was added, and 6.9 ml of concentrated nitric acid was added.
After the addition, the mixture was cooled to 55 ° C. to obtain a sodium organic acid solution. With the temperature of the organic acid sodium solution kept at 55 ° C., the photosensitive silver halide emulsion a (silver 0.038
Mol.) And 450 ml of pure water were added and stirred for 5 minutes. Next, 760.6 ml of a 1 mol / L silver nitrate solution was added over 2 minutes, the mixture was further stirred for 20 minutes, and water-soluble salts were removed by filtration. Thereafter, the conductivity of the filtrate was 2 μS /
The powder was repeatedly washed with deionized water, filtered and centrifugally dehydrated until the weight of the organic silver salt reached 37 cm.

(Preparation of Photosensitive Emulsion Dispersion) Polyvinyl butyral powder (manufactured by Monsanto: Butvar B)
-79) 14.57 g of methyl ethyl ketone 1457 g
And, while stirring with a dissolver-type homogenizer, 500 g of powdered organic silver salt A was gradually added and mixed well. Then 1% Zr beads (Toray) 80%
Filled media type disperser (Gettzmann)
At a peripheral speed of 0.5 m and a residence time in the mill of 0.5 minute to prepare a photosensitive emulsion dispersion.

(Preparation of Infrared Sensitizing Dye Liquid) Infrared sensitizing dye (IRD-1) 350 mg, 2-chloro-benzoic acid 1
3.96 g and 2.14 g of 5-methyl-2-mercaptobenzimidazole were dissolved in 73.4 ml of methanol in a dark place to prepare an infrared sensitizing dye solution.

(Preparation of Photosensitive Layer Coating Solution) 500 g of the photosensitive emulsion a and 100 g of methyl ethyl ketone were kept at 21 ° C. while stirring with algae. 0.45 g of pyrididium hydrobromide perbromide (PHP) was added, and the mixture was stirred for 1 hour. Further, 3.25 ml of calcium bromide (10% methanol solution) was added, and the mixture was stirred for 30 minutes. Next, after adding 7 ml of the infrared sensitizing dye solution and stirring for 1 hour,
The temperature is lowered to 13 ° C. and stirred for a further 30 minutes. 13 ℃
While keeping the temperature at 48 ° C., 48 g of polyvinyl butyral is added and dissolved sufficiently, and then the following additives are added.

Compounds of general formulas (I) and (II) Both listed in Table 1 Developer (1,1-bis (2-hydroxy-3,5-dimethylphenyl) -2-methylpropane) 15 g Phthalazine 5 g Tetrachlorophthalic acid 0.5 g 4-Methylphthalic acid 0.5 g After preparing a photosensitive layer coating solution, coating was performed while keeping the temperature at 13 ° C.

Incidentally, among the above-mentioned preparation methods, general formulas (I) and (I)
Similarly, for the coating solution to which the compound of (II) was not added, 1
After maintaining the stagnation at 3 ° C., the level of applying the compound of the general formula (I) and immediately applying was also carried out.

<Preparation of Photothermographic Material> Photosensitive material samples 1 to 9 were prepared by sequentially forming the following layers on a support.
In addition, each drying was performed at 75 ° C. for 5 minutes.

(Preparation of Back Surface Coating Solution) While stirring with 830 g of methyl ethyl ketone, cellulose acetate butyrate (manufactured by Eastman Chemical: C
AB381-20) 84.2 g, polyester resin (B
ostic company: VitelPE2200B) 4.5 g
Was added and dissolved. Add the infrared dye (IRF-
1) 0.30 g was added, and further, a fluorine-based activator (Surflon KH4 manufactured by Asahi Glass Co., Ltd.) dissolved in 43.2 g of methanol.
0) 4.5 g and 2.3 g of a fluorine-based activator (manufactured by Dainippon Ink Inc .: Megafac F120K) were added, and sufficiently stirred until dissolved. Finally, silica (manufactured by WR Grace: Syloid 64 × 60) dispersed in methyl ethyl ketone at a concentration of 1% with a dissolver type homogenizer.
(00) was added and stirred to prepare a coating solution on the back surface.

<Coating of Back Surface> The coating solution for the back surface prepared as described above was applied and dried by an extrusion coater so that the dry film thickness became 3.5 μm. Drying temperature 100
It dried for 5 minutes using the drying air of 10 degreeC and 10 degreeC of dew point temperature.

<Coating on the Photosensitive Layer Side> The coating solution for the photosensitive layer was applied so that the coating amount of silver was 2.0 g / m ² and polyvinyl butyral as a binder was 8.5 g / m ² .

(Preparation of calcium carbonate dispersion) Cellulose acetate butyrate (Eastman Chemi)
cal. CAB171-15) (7.5 g) is dissolved in methyl ethyl ketone (42.5 g), into which calcium carbonate (Specialty Minerals:
Super-Pflex 200) was added, and the mixture was dispersed with a dissolver-type homogenizer at 8000 rpm for 30 minutes to prepare a calcium carbonate dispersion.

(Preparation of Coating Solution for Surface Protective Layer) 96 g of cellulose acetate butyrate (described above: CAB171-15), 865 g of methyl ethyl ketone, and polymethyl methacrylic acid (Parroid A-21, manufactured by Rohm & Haas Co.) 4 0.5 g was added and dissolved. 1.5 g of a vinyl sulfone compound (HD-1), 1.0 g of benzotriazole, and a fluorine-based activator (see above: Surflon KH)
40) 1.0 was added and dissolved. Finally, 30 g of a calcium carbonate dispersion was added and stirred to prepare a coating solution for the surface protective layer.

<Surface protective layer coating> The above surface protective layer coating solution was applied so that the dry film thickness became 2.5 μm.

The structure of the additive used for preparing the photothermographic material sample is shown below. HD-1: 1,3-bis (vinylsulfonyl) -i-propanol

[0116]

Embedded image

(Evaluation of Performance) Samples 1 to 9 of Photosensitive Material Obtained
, The following performance evaluation was performed.

<< Exposure and Development >> From the emulsion side of each photosensitive material, exposure was performed by laser scanning using an exposing machine using a semiconductor laser having a wavelength of 800 to 820 nm as a multi-mode semiconductor laser as an exposure source. Was. At this time, an image was formed by setting the angle between the exposure surface of the photosensitive material and the exposure laser beam to 75 degrees (compared to the case where the angle was set to 90 degrees,
An image with little unevenness and excellent sharpness and the like was obtained unexpectedly).

Thereafter, heat development was performed at 120 ° C. for 15 seconds using an automatic developing machine having a heat drum so that the protective layer of the photosensitive material was in contact with the drum surface. At that time, exposure and development were performed in a room conditioned at 23 ° C. and 50% RH (relative humidity).

Evaluation of the obtained image was performed by using a digital densitometer PD.
A-65 (manufactured by Konica) was used. The result of the measurement is
The sensitivity (reciprocal of the ratio of the exposure amount giving a density 1.0 higher than the unexposed portion) and fog (density of unexposed portion D _min ) are evaluated.

<< Measurement of Remaining Amount of Solvent in Film >> A film area of 46.3 cm ² was cut out, finely chopped to about 5 mm, stored in a dedicated vial, and sealed with a septum and an aluminum cap. Manufactured by: Headspace Sampler Model HP7694. The gas chromatography (GC) connected to the headspace sampler was a Hewlett-Packard 5971 type equipped with a flame ionization detector (FID) as a detector. As main measurement conditions, a headspace sampler heating condition: 120 ° C., 20 minutes GC introduction temperature: 150 ° C., column: DB-624 manufactured by J & W Inc. Temperature rise: 45 ° C. 3 minutes → 100 ° C. (8 ° C./minute) To obtain a gas chromatogram. The measurement target solvents were methyl ethyl ketone and methanol, and after storing a certain amount of each of the solvents diluted in butanol in a dedicated vial bottle, the solvent was prepared using the peak area of the chromatogram obtained by measuring in the same manner as above. The amount of solvent remaining in the film was obtained using a calibration curve.

<< Evaluation of Film Peeling >> The photosensitive material sample exposed and developed as described above was visually observed to have a film peeling of 3 times.
It was rated on a scale. ○ The above are practical levels.

：: Sufficient quality as a product △: Quality on border line as a product, unsuitable ×: Unsuitable as a product The results are summarized in Table 1.

[0124]

[Table 1]

The superiority of the sample according to the present invention is clear.

[0126]

According to the image recording method and the image forming method of the present invention, there is no peeling of the film immediately after the thermal development, and there is no peeling of the film even when the film is applied to a shakasten, and an image excellent in diagnostic performance. Is obtained.

Claims (6)

[Claims] 1. A photosensitive layer containing at least (a) an organic silver salt, (b) a photocatalyst, (c) a reducing agent and (d) a binder on a support, and further comprising (e) an epoxy compound and An image forming method, wherein a photothermographic material having a combination of at least one compound selected from acid anhydrides is heat-developed in a state where a tip portion of 20 mm or less is unexposed. 2. A photosensitive layer containing at least (a) an organic silver salt, (b) a photocatalyst, (c) a reducing agent and (d) a binder on a support, and further comprising (e) an epoxy compound and An image forming method, wherein a photothermographic material having at least one compound selected from acid anhydrides is heat-developed in a state where the amount of a residual solvent after coating and drying is 500 mg / m ² or less. 3. The image forming method according to claim 1, wherein a compound selected from the group consisting of an epoxy compound and an acid anhydride as the component (e) is contained in the photosensitive layer. 4. The epoxy compound of the component (e) is represented by the following general formula (I), and the acid anhydride is represented by the following general formula (II). Image forming method. Embedded image [Wherein, R represents an alkylene group which may have a substituent, and X represents a divalent linking group. [Chemical formula 2] [In the formula, Z represents an atomic group necessary for forming a monocyclic or polycyclic ring system. ] 5. A laser scanning exposure apparatus for applying the photothermographic material according to claim 1 to a laser scanning exposure apparatus, wherein an angle between an exposed surface of the photosensitive material and a scanning laser beam is not substantially perpendicular. An image recording method, comprising exposing using an image. 6. The image recording method according to claim 5, wherein a laser scanning exposure device that emits a laser beam that is a vertical multi beam is used.