JP2002107871A - Heat developable image recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrahigh contrast heat developable image recording material stable to a change in development humidity. SOLUTION: The heat developable image recording material contains at least (1) photosensitive silver halide, (2) a reducible silver salt, (3) a reducing agent, (4) a binder and (5) at least one compound of formula (1) (where X is alkoxy, aryloxy, amino or alkylamino; Y is alkyl, aryl or a heterocyclic group; and M is a cation other than hydrogen ion) on the base.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat-developable image recording material. More specifically, the present invention relates to a heat-developable image recording material which is super-hard and stable to fluctuations in development conditions, particularly environmental humidity, and is suitable for photolithography.

[0002]

2. Description of the Related Art There are many known photosensitive materials having a photosensitive layer on a support and forming an image by exposing the image. Among them, there is a technique of forming an image by thermal development as a system that contributes to environmental conservation and can simplify an image forming unit. 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 conservation and space saving. Therefore, there is a need to develop 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 sharp black image having high resolution and sharpness. is needed. According to such a photothermographic material, it is possible to supply a customer with a simpler and more environmentally friendly photothermographic processing system that does not require solution processing chemicals.

A method of forming an image by thermal development is described in, for example, US Pat. Nos. 3,152,904 and 3,4,904.
57,075, and D.C. Crosta Bohr (K
"Thermally Processed Silver System (Thermally Processed)
Silver Systems) ”(Imaging
Processes and Materials (Imagin
g Processes and Material
s) Neblette 8th edition, J.M. Sturge (Stu
rge), V.I. Walworth,
A. Editing Shepp, Chapter 9, Chapter 279
1989). Such photothermographic materials typically comprise a non-photosensitive reducible silver source (eg, an organic silver salt), a catalytically active amount of a photocatalyst (eg, silver halide), and a silver reducing agent dispersed in an organic binder matrix. It is contained in a state. The photosensitive material is stable at room temperature, but when heated to a high temperature (for example, 80 ° C. or more) after exposure, silver is reduced through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and a reducing agent. Generate This oxidation-reduction reaction is promoted by the catalytic action of the latent image formed by the exposure. The silver formed by the reaction of the reducible silver salt in the exposed areas becomes black and forms an image because it contrasts with the unexposed areas.

[0004] US Patent No. 5,496,695,
Nos. 5,545,515 and 5,654,1
No. 30, No. 5,705,324, JP-A-11-119372, JP-A-11-109546, JP-A-11-231559, and the like include a super-high contrast containing a super-high contrast agent. A heat-developable photosensitive material has been disclosed.
However, in these photothermographic materials, sensitivity, Dmax, and line width vary greatly due to fluctuations in the humidity of the development environment, and improvement has been desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art. That is, an object of the present invention is to provide an ultra-high-contrast heat-developable image recording material that is stable against fluctuations in development humidity.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, the heat-developable image recording material contains a compound represented by the formula (1) as defined in the present specification. The present inventors have found that an excellent heat-developable image recording material exhibiting a desired effect can be provided by performing the method, and the present invention has been completed.

That is, according to the present invention, at least (1) photosensitive silver halide, (2) reducible silver salt, (3) reducing agent, (4) binder and (5) A heat-developable image recording material comprising at least one of the compounds represented by (1).

Embedded image [In the formula (1), X represents an alkoxy group, an aryloxy group, an amino group, or an alkylamino group;
Represents an alkyl group, an aryl group, or a heterocyclic group, and M represents a cation other than a hydrogen ion. ]

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and a method of the present invention will be described below in detail. In this specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit and an upper limit. The heat-developable image recording material of the present invention is characterized by containing a compound represented by the formula (1).

[0009]

Embedded image

In the formula (1), X represents an alkoxy group (preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, more preferably 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms). E.g., methoxy, ethoxy, propoxy, isopropoxy, tert-butoxy, n
-Octyloxy, 2-methoxyethoxy), an aryloxy group (preferably having a total carbon number of 6 to 30, more preferably having a total carbon number of 6 to 20, and particularly preferably having a total carbon number of 6)
To 10 substituted or unsubstituted aryloxy groups, for example, phenoxy, 4-methylphenoxy, 4-tert-butylphenoxy, 4-methoxyphenoxy, 4-dimethylaminophenoxy), unsubstituted amino group, or alkylamino group (Preferably total carbon number 1-30, more preferably total carbon number 1-20, particularly preferably total carbon number 1
10 to 10 substituted or unsubstituted alkylamino groups, including saturated cyclic ones, for example, methylamino, ethylamino, dimethylamino, diethylamino, pyrrolidino, morpholino, 2-hydroxyethylamino, 2-methoxyethylamino, Bis (2-methoxyethyl) amino). In the formula (1), X is preferably an alkoxy group or an alkylamino group.

In X of the formula (1), substituents of the alkoxy group, the aryloxy group and the alkylamino group include:
For example, an alkyl group (including a cycloalkyl group and a bicycloalkyl group), an alkenyl group (a cycloalkenyl group,
Bicycloalkenyl group), alkynyl group, aryl group, heterocyclic group, cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group , Alkoxycarbonyloxy group, aryloxycarbonyloxy, amino group (including anilino group), acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino Group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, arylo group Aryloxycarbonyl group, an alkoxycarbonyl group, a carbamoyl group, an aryl or heterocyclic azo group, an imido group, a phosphino group, a phosphinyl group,
Examples include a phosphinyloxy group, a phosphinylamino group, and a silyl group.

In the formula (1), Y represents an alkyl group [straight-chain, branched, cyclic or a combination thereof, or a substituted or unsubstituted alkyl group. They include alkyl groups (preferably alkyl groups having 1 to 30 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, tert-butyl, n-octyl, eicosyl, 2-chloroethyl,
-Cyanoethyl, 2-ethylhexyl), a cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having a total of 3 to 30 carbon atoms, for example, cyclohexyl, cyclopentyl, 4-n-dodecylcyclohexyl), a bicycloalkyl group (preferably Is a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, that is, one hydrogen atom is converted from a bicycloalkane having 5 to 30 carbon atoms.
It is a monovalent group removed. For example, bicyclo [1,
2,2] Heptan-2-yl, bicyclo [2,2,2]
Octane-3-yl), and a tricyclo structure having many ring structures. An alkyl group in the substituents described below (eg, an alkyl group of an alkylthio group)
Also represents an alkyl group having such a concept. ], An aryl group (preferably a substituted or unsubstituted aryl group having 6 to 50 carbon atoms, such as phenyl, p-tolyl, naphthyl, m-chlorophenyl, o-hexadecanoylaminophenyl), or a heterocyclic group (preferably Is 5 or 6
A monovalent group obtained by removing one hydrogen atom from a substituted or unsubstituted aromatic or non-aromatic heterocyclic compound having 1 to 5 carbon atoms, and more preferably a 5 or 6-membered carbon atom having 3 to 50 carbon atoms in total. It is an aromatic heterocyclic group. For example, 2-
Furyl, 2-thienyl, 2-pyrimidinyl, 2-benzothiazolyl). In the formula (1), Y is preferably an aryl group.

In the formula (1), an alkyl group represented by Y,
As the substituent of the aryl group and the heterocyclic group, the same groups as those described as the substituent for X can be used,
Most preferred substituents are acylamino, aminocarbonylamino, and alkoxycarbonylamino groups having a total carbon number of 8 to 50.

In the formula (1), M represents a cation other than a hydrogen ion, that is, an oxygen anion counter cation, which may be a metal ion or a nonmetal ion. As cations other than hydrogen ions, for example, sodium, potassium, magnesium, calcium, zinc,
Silver and quaternary ammonium (for example, tetrabutylammonium, benzyltrimethylammonium and the like) and the like can be mentioned. In the formula (1), M is preferably sodium, potassium, zinc, or quaternary ammonium. next,
Specific examples of the compound of the formula (1) used in the present invention are shown below, but the present invention is not limited thereto.

[0015]

Embedded image

[0016]

Embedded image

[0017]

Embedded image

[0018]

Embedded image

[0019]

Embedded image

[0020]

Embedded image

The compound of the formula (1) can be prepared by a known method.
-It can be easily obtained by synthesizing a pyrazolone compound, formylating it with a Vilsmeier reagent or the like, and treating it under alkaline conditions. A specific synthesis example is shown below. (Synthesis of Compound Example A-4) 120 g of p-nitrophenylhydrazine and 200 g of ethyl 3-amino-3-ethoxyacrylate hydrochloride were added to 650 m of dimethylacetamide.
and stirred at room temperature for 30 minutes. 450 g of a 28% methanol solution of sodium methoxide was added to the reaction solution, and the mixture was further stirred at room temperature for 30 minutes. Concentrated hydrochloric acid 2
00 ml and 400 ml of water were added, and the precipitated crystals were filtered and washed with water. 150 g of intermediate (A) was obtained. Intermediate (A) 100 g, reduced iron 160 g, isopropyl alcohol 800 ml, water 80 ml and ammonium chloride 2
g of the mixture was heated to reflux for 2 hours. The insolubles were filtered through celite while hot, 50 ml of concentrated hydrochloric acid was added to the filtrate, and the solvent was distilled off under reduced pressure. Ethanol was added to the residue, and the precipitated crystals were filtered. 70 g of intermediate (B) was obtained.

26 g of the intermediate (B) and 20 g of pyridine were dissolved in 120 ml of dimethylacetamide, and 27 g of isopalmitic acid chloride was slowly added dropwise while cooling with ice. After stirring for 30 minutes, 150 ml of diluted hydrochloric acid was added, and the precipitated crystals were filtered. Recrystallized from acetonitrile,
35 g of intermediate (C) were obtained. 35 g of the intermediate (C)
The resultant was dissolved in 170 ml of F, and 11 ml of dimethylformamide dimethyl acetal was added at room temperature. The precipitated crystals were filtered. 25 g of intermediate (D) were obtained. Intermediate (D) 16
g, 90 ml of methanol and 7.5 ml of a 5N sodium hydroxide solution were stirred at 50 ° C. for 30 minutes, and then 50 ml of 20% saline was added. The precipitated crystals were filtered and sufficiently washed with water. 14 g of Compound Example A-4 was obtained. Intermediate (A), Intermediate (B), Intermediate (C) and Intermediate (D)
The structure of is shown.

[0023]

Embedded image

The compound of the formula (1) used in the present invention may be water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethyl sulfoxide. , Methyl cellosolve and the like. Also, by an already well-known emulsification dispersion method, dibutyl phthalate, tricresyl phosphate, oil such as glyceryl triacetate or diethyl phthalate, dissolved using an auxiliary solvent such as ethyl acetate or cyclohexanone, mechanically emulsified dispersion. Can be prepared and used. Alternatively, the powder can be dispersed in water by a method known as a solid dispersion method using a ball mill, a colloid mill, a sand grinder mill, a Menton-Gaulin, a microfluidizer, or ultrasonic waves.

The compound of the formula (1) used in the present invention may be added to any layer on the image forming layer side with respect to the support.
It is preferably added to a layer containing a silver salt or a layer adjacent thereto.

The addition amount of the compound of the formula (1) used in the present invention depends on the kind of the photographically useful group.
It is preferably 0 ^-6 to 1 mol, more preferably 1 × 10 ^{-5 to} 5 × 10 ^-1 mol, and most preferably 2 × 10 ^-5 to 2 × 10 ^-1 mol. Only one compound of formula (1) may be used,
Two or more kinds may be used in combination.

The heat-developable image recording material of the present invention contains an organic silver salt as a reducible silver salt. The organic silver salt that can be used in the present invention is relatively stable to light, but at 80 ° C. or higher in the presence of an exposed photocatalyst (such as a latent image of a photosensitive silver halide) and a reducing agent. It is a silver salt that forms a silver image when heated as described above. The organic silver salt can be any organic material including a source of reducible silver ions. Silver salts of organic acids, especially (C 10-30,
Silver salts of long chain fatty carboxylic acids (preferably 15 to 28) are preferred. Also preferred are organic or inorganic silver salt complexes in which the ligand has a complex stability constant in the range of 4.0 to 10.0.
The silver donor material can preferably comprise about 5 to 70% by weight of the imaging layer. As a preferred organic silver salt,
A silver salt of an organic compound having a carboxyl group can be mentioned. Specific examples include silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids, but are not limited thereto. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver arachidate,
Silver stearate, silver oleate, silver laurate, silver caproate, silver myristate, silver palmitate, silver maleate, silver fumarate, silver tartrate, silver linoleate, silver butyrate and silver camphorate, mixtures thereof, etc. including.

In the present invention, it is preferable to use silver behenate having a silver behenate content of 75 mol% or more, and silver behenate content of 85 mol% or more. It is more preferable to use the organic acid silver. Here, the content of silver behenate indicates the mole fraction of silver behenate with respect to the organic acid silver used. As the organic acid silver other than silver behenate contained in the organic acid silver used in the present invention, those mentioned above can be preferably used.

The organic acid silver which is preferably used in the present invention is
It is prepared by reacting silver nitrate with a solution or suspension of the above-mentioned alkali metal salt of an organic acid (including Na salt, K salt, Li salt and the like). These preparation methods are described in Japanese Patent Application No. 11-104187, paragraph No. 00.
19 to 0021 can be used. In the present invention, a method of preparing an organic silver salt by adding a silver nitrate aqueous solution and an organic acid alkali metal salt solution into a means for mixing a sealed liquid can be preferably used. Specifically, the method described in Japanese Patent Application No. 11-203413 can be used. In the present invention, a water-soluble dispersant can be added to the aqueous silver nitrate solution and the organic acid alkali metal salt solution or the reaction solution during the preparation of the organic acid silver. Regarding the type and amount of the dispersant used here, refer to Japanese Patent Application No. 11-11 / 1999.
No. 5457, paragraph 0052.

The silver salt of an organic acid used in the present invention is preferably prepared in the presence of a tertiary alcohol. As the tertiary alcohol, a compound having a total carbon number of 15 or less is preferable, and a compound having a total carbon number of 10 or less is particularly preferable. Preferred examples of the tertiary alcohol include tert-butanol, but the tertiary alcohol that can be used in the present invention is not limited to this. The tertiary alcohol used in the present invention may be added at any time during the preparation of the organic acid silver salt.
It is preferable to dissolve and use the organic acid alkali metal salt. Further, the tertiary alcohol used in the present invention is 0.01 to 1 in mass ratio to water as a solvent at the time of preparing the silver salt of an organic acid.
Although it can be used in the range of 0, it is preferable to use in the range of 0.03-1.

The shape and size of the organic silver salt which can be used in the present invention are not particularly limited.
It is preferable to use those described in paragraph 0024 of the specification of JP-A-187. The shape of the organic silver salt can be determined from a transmission electron microscope image of the organic silver salt dispersion. Another method of measuring monodispersity is to determine the standard deviation of the volume-weighted average diameter of the organic silver salt, and the percentage (coefficient of variation) divided by the volume-weighted average diameter is preferably 80% or less, more preferably Preferably 50% or less, more preferably 30%
% Or less. As a measuring method, for example, an organic silver salt dispersed in a liquid is irradiated with a laser beam, and an autocorrelation function with respect to a time change of fluctuation of the scattered light is obtained from a particle size (volume weighted average diameter) obtained. be able to. The average particle size in this measurement method is 0.1.
A solid fine particle dispersion of from 0.05 μm to 10.0 μm is preferred. A more preferred average particle size is 0.1 μm to 5.0.
μm, more preferably the average particle size is 0.1 μm to
2.0 μm.

The organic silver salt used in the present invention is preferably desalted. The desalting method is not particularly limited, and known methods can be used, but centrifugal filtration, suction filtration,
Known filtration methods such as ultrafiltration and floc-forming water washing by a coagulation method can be preferably used. As for the method of ultrafiltration, the method described in Japanese Patent Application No. 11-115457 can be used. In the present invention, high S / N
In, for the purpose of obtaining an organic silver salt solid dispersion having a small particle size and no aggregation, including an organic silver salt which is an image forming medium,
Further, it is preferable to use a dispersion method in which an aqueous dispersion substantially free of a photosensitive silver salt is converted into a high-speed stream, and then the pressure is reduced. These dispersing methods are described in Japanese Patent Application No. 11-104.
No. 187, paragraphs 0027 to 0038 can be used. The particle size distribution of the organic silver salt solid fine particle dispersion used in the present invention is preferably monodispersed. Specifically, the percentage (coefficient of variation) of the value obtained by dividing the standard deviation of the volume load average diameter by the volume load average diameter is 8
0% or less, more preferably 50% or less, further preferably 30% or less.

The dispersion of the organic silver salt solid fine particles used in the present invention comprises at least an organic silver salt and water. The ratio between the organic silver salt and water is not particularly limited, but the ratio of the organic silver salt to the whole is preferably 5 to 50% by mass, and particularly preferably 10 to 30% by mass.
It is preferable to use the above-mentioned dispersing aid, but it is preferable to use the dispersing aid in a minimum amount within a range suitable for minimizing the particle size.
A range of 15% by mass is preferred. In the present invention, the organic silver salt can be used in a desired amount.
m ² is preferred, and more preferably 1 to 3 g / m ² .

In the present invention, it is preferable to add a metal ion selected from Ca, Mg, Zn and Ag to the non-photosensitive organic silver salt. Regarding the addition of a metal ion selected from Ca, Mg, Zn and Ag to the non-photosensitive organic silver salt,
It is preferably added in the form of a water-soluble metal salt which is not a halide, and specifically, it is preferably added in the form of a nitrate or a sulfate. The addition of a halide is not preferable because it deteriorates the image storability of the processed photosensitive material due to light (such as room light or sunlight), that is, the so-called printout property. For this reason, in the present invention, it is preferable to add in the form of a water-soluble metal salt which is not a halide. The metal ions selected from Ca, Mg, Zn and Ag preferably used in the present invention are added after the formation of the particles of the non-photosensitive organic silver salt, immediately after the formation of the particles, before the dispersion, after the dispersion and in the preparation of the coating solution. The timing may be any time as long as immediately before and after application such as before and after, preferably after dispersion and before and after preparation of the coating solution. In the present invention, the addition amount of the metal ion selected from Ca, Mg, Zn and Ag is preferably 10 ^-3 to 10 ^-1 mol per mol of non-photosensitive organic silver, and particularly preferably 5 ×
It is preferably from 10 ^{−3 to} 5 × 10 ⁻² mol.

The heat-developable image recording material of the present invention contains a photosensitive silver halide. The photosensitive silver halide used in the present invention is not particularly limited as a halogen composition, and silver chloride, silver chlorobromide, silver bromide, silver iodobromide, and silver iodochlorobromide can be used. The grain formation of the photosensitive silver halide emulsion is described in paragraph No. 021 of JP-A-11-119374.
Particles can be formed by the method described in Nos. 7 to 0224, but the method is not particularly limited to this method.
Examples of the shape of silver halide grains include cubic, octahedral, tetradecahedral, tabular, spherical, rod-like, potato-like and the like. In the present invention, cubic grains or tabular grains are particularly preferred. The characteristics of the particle shape such as the particle aspect ratio and plane index are described in JP-A-11-119.
This is the same as that described in paragraph No. 0225 of JP-A-374. The distribution of the halogen composition may be uniform inside and on the surface of the silver halide grains, and the halogen composition may be changed stepwise or may be changed continuously. Further, silver halide grains having a core / shell structure can be preferably used. As the structure, core / shell particles having preferably a 2- to 5-layer structure, more preferably a 2- to 4-layer structure, can be used. A technique for localizing silver bromide on the surface of silver chloride or silver chlorobromide grains can also be preferably used.

The particle size of the silver halide grains used in the present invention
The cloth has a value of monodispersity of 30% or less, preferably 1%.
-20%, and even 5-15%. Just here
Permeability is the percentage of the standard deviation of the particle size divided by the average particle size.
(%) (Coefficient of variation). Note that
The size of silver halide grains is, for convenience, the case of cubic grains.
Represents the edge length, other particles (octahedron, tetradecahedron, flat
Shape, etc.) is calculated by the projected area circle equivalent diameter. For use in the present invention
Some photosensitive silver halide grains are from Group VII of the Periodic Table.
Alternatively, it contains a Group VIII metal or metal complex.
You. Group VII or VIII metal of the periodic table
Or preferably rhodium as the central metal of the metal complex,
Rhenium, ruthenium, osmium, iridium
You. Particularly preferred metal complexes are (NH_Four)_ThreeRh (H
_TwoO) Cl_Five, K_TwoRu (NO) Cl_Five, K_ThreeIrCl₆, K
_FourFe (CN)₆It is. These metal complexes can be of one type
A combination of two or more complexes of the same and different metals
You may. The preferred content is 1 × 10 ^-9
Mol ~ 1 x 10^-3The molar range is preferably 1 × 10^-8Mo
~ 1 x 10^-FourA molar range is more preferred. Concrete money
The structure of the genus complex is disclosed in JP-A-7-225449
Can be used. This
Regarding the types and addition methods of these heavy metals,
No. 227374, paragraphs 0227 to 0240.
It is listed.

The photosensitive silver halide grains can be desalted by a water washing method known in the art such as a noodle method or a flocculation method, but in the present invention, it may or may not be desalted. . The photosensitive silver halide emulsion used in the present invention is preferably chemically sensitized. The chemical sensitization is described in JP-A-11-119374, paragraph 02.
It is preferable to use the methods described in JP-A-42-0250. The silver halide emulsion used in the present invention is prepared by the method described in EP-A-293,917.
A thiosulfonic acid compound may be added.

As the gelatin contained in the photosensitive silver halide used in the present invention, a low molecular weight gelatin is used in order to maintain a good dispersion state of the photosensitive silver halide emulsion in the coating solution containing an organic silver salt. Is preferred. The low molecular weight gelatin has a molecular weight of 500 to 60,000, preferably 1,000 to 40,000. These low-molecular-weight gelatins may be used at the time of grain formation or at the time of dispersion after desalting, but are preferably used at the time of dispersion after desalting. When forming particles, use normal gelatin (molecular weight of about 100,000),
Low-molecular-weight gelatin may be used at the time of dispersion after desalting. The concentration of the dispersion medium can be 0.05 to 20% by mass, but a concentration range of 5 to 15% by mass is preferable for handling. As the type of gelatin, alkali-treated gelatin is usually used, but modified gelatin such as acid-treated gelatin and phthalated gelatin can also be used.

As the silver halide emulsion in the light-sensitive material used in the present invention, only one kind may be used, or two or more kinds may be used (for example, those having different average grain sizes, different halogen compositions, different crystal habits). And those having different chemical sensitization conditions). The amount of the photosensitive silver halide used in the present invention is preferably from 0.01 mol to 0.5 mol per 1 mol of the organic silver salt, and more preferably from 0.1 mol to 0.5 mol.
02 mol to 0.3 mol is more preferable, and 0.03 mol to
0.25 mol is particularly preferred. About the mixing method and mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the silver halide particles and the organic silver salt which have been respectively prepared are mixed with a high-speed stirrer, a ball mill, a sand mill, a colloid mill, a vibration mill, A method of mixing with a homogenizer or the like,
Alternatively, there is a method of preparing an organic silver salt by mixing a photosensitive silver halide prepared at any timing during the preparation of the organic silver salt, and the like.However, there is no particular limitation as long as the effects of the present invention can be sufficiently obtained. Absent. In addition, mixing two or more kinds of aqueous dispersions of organic silver salts and two or more kinds of aqueous dispersions of photosensitive silver salts is a preferable method for adjusting photographic characteristics.

In the present invention, a high-contrast accelerator can be used in combination for forming an ultra-high-contrast image. For example, amine compounds described in U.S. Pat. No. 5,545,505, specifically AM-1 to AM-5, U.S. Pat.
No. 507, specifically, HA-1 to HA-11, US Pat. No. 5,545,507.
Acrylonitriles described in the specification, specifically CN
-1 to CN-13, hydrazine compounds described in U.S. Pat. No. 5,558,983, specifically CA-1 to CA-13.
CA-6, onium salts described in JP-A-9-297368, specifically A-1 to A-42, B-1 to B
-27, C-1 to C-14 and the like can be used.

In a photothermographic material having a non-photosensitive silver salt, a photosensitive silver halide and a binder, formic acid or formate is a strong fogging substance. In the present invention, the content of formic acid or formate on the side of the heat-developable image recording material having the photosensitive silver halide-containing image forming layer is less than 1% silver.
It is preferably at most 5 mmol, more preferably at most 1 mmol, per mole.

In the heat-developable image recording material of the present invention, an acid or a salt thereof formed by hydration of diphosphorus pentoxide is preferably used in combination with a super-high contrast agent. Acids or salts thereof formed by hydration of diphosphorus pentoxide include metaphosphoric acid (salt), pyrophosphoric acid (salt), orthophosphoric acid (salt), triphosphoric acid (salt), tetraphosphoric acid (salt), hexametaline Acids (salts) and the like can be mentioned. Particularly preferred acids or salts thereof formed by hydration of diphosphorus pentoxide include orthophosphoric acid (salt) and hexametaphosphoric acid (salt). Specific salts include sodium orthophosphate, sodium dihydrogen orthophosphate, sodium hexametaphosphate, and ammonium hexametaphosphate. The acid or salt thereof formed by hydration of diphosphorus pentoxide, which can be preferably used in the present invention, is added to the image forming layer or the binder layer adjacent thereto in that a desired effect is exhibited in a small amount. Amount of acid or salt thereof formed by hydration of diphosphorus pentoxide (image recording material 1
m ² per coating amount) may be desired amount depending on the performance such as sensitivity and fog, preferably 0.1 to 500 mg / m ^2, 0.5 to 100 mg / m ² is more preferable.

The heat-developable image recording material of the present invention contains a reducing agent. The reducing agent used in the present invention is any substance that reduces silver ions to metallic silver, preferably an organic substance. Conventional photographic developers such as phenidone, hydroquinone and catechol are useful, but hindered phenol reducing agents are preferred. The reducing agent is preferably contained in an amount of 5 to 50 mol% based on 1 mol of silver on the surface having the image forming layer.
More preferably, it is contained at 0 to 40 mol%. The layer to which the reducing agent is added may be any layer on the image forming layer side with respect to the support. When it is added to a layer other than the image forming layer, it is preferable to use a relatively large amount of 10 to 50 mol% with respect to 1 mol of silver. Further, the reducing agent may be a so-called precursor which is derivatized so as to function effectively only during development.

In the heat-developable image recording material using an organic silver salt, a wide range of reducing agents can be used. For example, JP-A-46-6074, JP-A-47-1238, JP-A-47-33621, and JP-A-49-46427.
JP, JP-A-49-115540, JP-A-50-143
Nos. 34, 50-36110, 50-14
Nos. 7711, 51-32632 and 51-
No. 1023721, JP-A-51-32324, JP-A-51-51933, JP-A-52-84727,
JP-A-55-108654, JP-A-56-146133, JP-A-57-82828, and JP-A-57-82829
JP, JP-A-6-3793, U.S. Pat.
Nos. 79,426, 3,751,252, 3,751,255, and 3,763.
Nos. 1,270, 3,782,949, 3,839,048, 3,92
No. 8,686, 5,464,738, German Patent 2,321,328, European Patent Publication 692,732 and the like are used. be able to. For example, amide oximes such as phenylamide oxime, 2-thienyl amide oxime and p-phenoxyphenyl amide oxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; A combination of an aliphatic carboxylic acid aryl hydrazide such as a combination of β-phenylhydrazine and ascorbic acid and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (for example, hydroquinone and bis (ethoxy) Ethyl) hydroxylamine, piperidinohexose reductone or a combination of formyl-4-methylphenylhydrazine, etc.); phenylhydroxamic acid, p-hydroxyphenylhydroxam And hydroxamic acids, such as β- ants Nin hydroxamic acid;
A combination of azine and sulfonamidophenol (for example, phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol); α such as ethyl-α-cyano-2-methylphenylacetate, ethyl-α-cyanophenylacetate A cyanophenylacetic acid derivative; 2,2′-dihydroxy-1,1′-binaphthyl,
6,6′-dibromo-2,2′-dihydroxy-1,1 ′
Bis-β-naphthol as exemplified by binaphthyl and bis (2-hydroxy-1-naphthyl) methane;
A combination of bis-β-naphthol and a 1,3-dihydroxybenzene derivative (for example, 2,4-dihydroxybenzophenone or 2 ′, 4′-dihydroxyacetophenone); Pyrazolones; reductones as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone; 2,6-dichloro-4-benzenesulfonamidophenol and p A sulfonamidophenol reducing agent such as benzenesulfonamidophenol; 2-phenylindane-1,3-dione and the like; 2,2-dimethyl-7-tert-butyl-
Chromanes such as 6-hydroxychroman; 1,4-dihydropyridines such as 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine; bisphenols (for example, bis (2-hydroxy-3-tert-
Butyl-5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane,
4,4-ethylidene-bis (2-tert-butyl-6
-Methylphenol), 1,1, -bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and 2,2-bis (3,5-dimethyl-
4-hydroxyphenyl) propane, etc.); ascorbic acid derivatives (eg, 1-ascorbyl palmitate,
Aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indane-1,3-diones;
Chromanol (such as tocopherol). Particularly preferred reducing agents are bisphenol, chromanol.

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

When an additive known as a "toning agent" for improving an image is included, the optical density may be increased.
The toning agent may also be advantageous in forming a black silver image. The color-toning agent is preferably contained in the layer on the image forming layer side with respect to the support in an amount of 0.1 to 50% mol, more preferably 0.5 to 20% mol, per mol of silver. Further, the color tone agent may be a so-called precursor which is derivatized so as to function effectively only during development.

In a heat-developable image recording material using an organic silver salt, a wide range of color toning agents can be used. For example, JP-A-46-6077 and JP-A-47-10282
JP-A-49-5019, JP-A-49-5020, JP-A-49-91215, and JP-A-49-91215
JP, 50-5024, and 50-32927
JP, 50-67132, and 50-6764
No. 1, No. 50-114217, No. 51-32
No. 23, No. 51-27923, No. 52-14
No. 788, No. 52-99813, No. 53-1
No. 020, 53-76020, 54-1
Nos. 56524, 54-156525, 6
1-1183642, JP-A-4-56848, JP-B-49-10727, and 54-2033.
No. 3, U.S. Pat. Nos. 3,080,254, 3,446,648, and 3,782,94.
No. 1, No. 4,123,282, No. 4,510,236, British Patent No. 1,380,
No. 795, Belgian Patent No. 841,910 and the like can be used. Specific examples of toning agents include phthalimide and N-hydroxyphthalimide; succinimide, pyrazolin-5-one, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4- Cyclic imides such as thiazolidinedione; naphthalimides (eg, N-hydroxy-1,8
-Naphthalimide); cobalt complex (e.g., cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4-triazole, 2,4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,
2,4-triazole and 2,5-dimercapto-
Mercaptans exemplified by 1,3,4-thiadiazole; N- (aminomethyl) aryldicarboximides (for example, (N, N-dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene- 2,3-dicarboximide); and blocked pyrazoles, isothiuronium derivatives, and certain photobleaching agents (eg, N, N'-hexamethylenebis (1-carbamoyl-3,5-dimethylpyrazole), 1,8 -(3,6-diazaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) -benzothiazole; and 3-ethyl-5-[(3-ethyl-2-benzothiazolinylidene) ) -1-Methylethylidene] -2-thio-
2,4-oxazolidinedione; phthalazinone, phthalazinone derivative or metal salt, or 4- (1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-
Dimethoxyphthalazinone and 2,3-dihydro-1,
Derivatives such as 4-phthalazinedione; combinations of phthalazinone and phthalic acid derivatives (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); phthalazine, phthalazine derivatives (for example, 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine, 6-
Derivatives such as isobutylphthalazine, 6-tert-butylphthalazine, 5,7-dimethylphthalazine, and 2,3-dihydrophthalazine) or metal salts; phthalazine and its derivatives and phthalic acid derivatives (for example, phthalic acid, Combinations with 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); quinazolinedione, benzoxazine or naphthoxazine derivatives; halide ions for silver halide formation in situ as well as as color tone regulators Complexes which also function as sources of, for example, ammonium hexachlororhodate (III), rhodium bromide, rhodium nitrate and potassium hexachlororhodate (III); inorganic peroxides and persulfates, for example ammonium disulfide And peroxide water ; 1,3 benzoxazine -2,
4-dione, 8-methyl-1,3-benzoxazine-
Benzoxazine-2, such as 2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione;
4-dione; pyrimidine and asymmetric-triazine (eg, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (eg, 3,6-dimercapto-1, 4-diphenyl-1H, 4H-2,3a,
5,6a-tetraazapentalene and 1,4-di (o-chlorophenyl) -3,6-dimercapto-1
H, 4H-2,3a, 5,6a-tetraazapentalene) and the like.

In the present invention, as a color tone agent,
Phthalazine derivatives represented by the general formula (F) described in JP-A-35631 are preferably used. Specifically, the color toning agent in which A-1 to A-10 described in the same specification are preferably used may be added by any method such as a solution, a powder, and a solid fine particle dispersion. Dispersion of solid fine particles can be performed by a known finely-refining means (for example, ball mill, vibrating ball mill, sand mill,
Colloid mill, jet mill, roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

The surface pH of the heat-developable image recording material of the present invention before the heat development treatment is preferably 6.0 or less, more preferably 5.5 or less. The lower limit is not particularly limited, but is about 3. For adjusting the film surface pH, it is preferable to use an organic acid such as a phthalic acid derivative, a nonvolatile acid such as sulfuric acid, or a volatile base such as ammonia from the viewpoint of reducing the film surface pH. In particular, ammonia is preferable for achieving a low film surface pH since ammonia is easily volatilized and can be removed before the application step and the heat development. The method of measuring the film surface pH is described in paragraph No. 0123 of Japanese Patent Application No. 11-87297.

In the heat-developable image recording material of the present invention, the silver halide emulsion and / or the organic silver salt are further protected against the formation of additional fog by an antifoggant, a stabilizer and a stabilizer precursor. In addition, it is possible to stabilize against a decrease in sensitivity during storage of inventory. Suitable antifoggants which can be used alone or in combination,
Stabilizers and stabilizer precursors are disclosed in US Pat. No. 2,131,
Nos. 038 and 2,694,716; thiazonium salts described in US Pat. No. 2,886,43.
No. 7, 244, 605, Azaindene, U.S. Pat. No. 2,728,663, mercury salt, U.S. Pat. No. 3,287,135. Urazole, US Patent No. 3,235,6
No. 52, sulfocatechol, British Patent No. 6
Oxime, nitrone, nitroindazole described in US Pat. No. 23,448, polyvalent metal salt described in US Pat. No. 2,839,405, US Pat. No. 3,220,83.
No. 9,566,263 and U.S. Pat. Nos. 2,597,
No. 915, palladium, platinum and gold salts,
U.S. Pat. No. 4,108,665 and U.S. Pat.
No. 442,202, halogen-substituted organic compounds described in U.S. Pat. Nos. 4,128,557 and 4,137,079, and 4,138,365.
And the phosphorus compounds described in US Pat. No. 4,411,985.

The heat-developable image recording material of the present invention may contain benzoic acids for the purpose of increasing the sensitivity and preventing fog. The benzoic acid used in the present invention may be any benzoic acid derivative, and a preferred example is US Pat.
Nos. 84,939, 4,152,160, JP-A-9-329,863, and 9-32986.
No. 4, JP-A-9-28637, and the like. The benzoic acid may be added to any layer of the heat-developable image recording material, but is preferably added to the layer on the image forming layer side with respect to the support, more preferably to the organic silver salt-containing layer. The addition of benzoic acids may be performed at any step in the preparation of the coating solution, and when the benzoic acid is added to the organic silver salt-containing layer, any step from the preparation of the organic silver salt to the preparation of the coating solution may be performed, but the coating is performed after the preparation of the organic silver salt. Immediately before is preferred. The benzoic acid may be added by any method such as powder, solution, and fine particle dispersion. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent, and a color tone agent. The benzoic acid may be added in any amount, but is preferably 1 × 10 ⁻⁶ mol / mol silver.
It is preferably 2 mol, more preferably 1 × 10 ⁻³ mol to 0.5 mol.

Although not essential for practicing the present invention,
It may be advantageous to add a mercury (II) salt as an antifoggant to the imaging layer. Preferred mercury (II) salts for this purpose are mercury acetate and mercury bromide. The added amount of mercury used in the present invention is as follows.
It is preferably in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol, more preferably 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol per mol.

The antifoggants particularly preferably used in the present invention are organic halides.
No. 119624, No. 50-120328, No. 51-121332, No. 54-58022, No. 56-70543, No. 56-99335, No. 59-90842, No. 61-12964.
No. 2, JP-A-62-129845, and JP-A-6-2
JP 08191, JP 7-5621, JP 7-27
No. 81, 8-15809, U.S. Pat.
Compounds disclosed in 340,712, 5,369,000, and 5,464,737 are exemplified. Japanese Patent Application No. 11-87297
The hydrophilic organic halide represented by the formula (P) described in the specification is preferably used as an antifoggant. Specifically, (P-1) to (P-118) described in the same specification
Is preferably used. The amount of organic halide added is
Mol amount per mol Ag (mol / mol Ag)
And preferably 1 × 10 ^{−5 to 2} mol / molA
g, more preferably 5 × 10 ^{−5 to 1} mol / molA
g, more preferably 1 × 10 ^{-4 to} 5 × 10 ^-1 mol / g.
molAg. These may be used alone or in combination of two or more.

Also, Japanese Patent Application No. 11-87297 describes
Salicylic acid derivative represented by the formula (Z)
It is preferably used as a stopping agent. Specifically, the same specification
(A-1) to (A-60) described in are preferably used.
You. The amount of the salicylic acid derivative represented by the formula (Z) is:
Mol amount per mol Ag (mol / mol Ag)
, Preferably 1 × 10^-Five~ 5 × 10^-1mol /
molAg, more preferably 5 × 10^-Five~ 1 × 10^-1m
ol / mol Ag, more preferably 1 × 10 ^-Four~ 5x
10^-2mol / mol Ag. These are only one kind
They may be used alone or in combination of two or more. Preferred for the present invention
Formalin scavenge is used as an antifoggant
Is effective, for example, Japanese Patent Application No. 11-23995.
Compound represented by formula (S) described in the specification and examples thereof
Compounds (S-1) to (S-24).

The antifoggant used in the present invention may be water or a suitable organic solvent such as alcohols (methanol,
It can be used by dissolving in ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethylsulfoxide, methylcellosolve and the like. In addition, dibutyl phthalate,
An oil such as tricresyl phosphate, glyceryl triacetate or diethyl phthalate, or an auxiliary solvent such as ethyl acetate or cyclohexanone can be used to dissolve and mechanically prepare and use an emulsified dispersion. Alternatively, the powder can be dispersed in water by a ball mill, a colloid mill, a sand grinder mill, a Menton-Gaulin, a microfluidizer or an ultrasonic wave by a method known as a solid dispersion method. The antifoggant used in the present invention may be added to the layer on the image forming layer side with respect to the support, that is, the image forming layer or any other layer on the layer side. Is preferably added. In the case of a heat-developable image recording material, the image forming layer is a layer containing a reducible silver salt (organic silver salt), and preferably an image forming layer further containing a photosensitive silver halide.

The image recording material of the present invention may contain a mercapto compound for the purpose of controlling or developing by suppressing or accelerating the development, or improving the storability before and after the development.
A disulfide compound and a thione compound can be contained. When a mercapto compound is used in the present invention, any structure may be used, but Ar-SM, Ar-S-
Those represented by S-Ar are preferred. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or a condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole,
Benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole,
Triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring may be, for example, halogen (eg, Br and Cl), hydroxy, amino, carboxy, alkyl (eg, having one or more carbon atoms, preferably 1-4 carbon atoms), alkoxy ( For example, it may have a substituent selected from the group consisting of one or more carbon atoms, preferably those having 1 to 4 carbon atoms, and aryl (which may have a substituent). Good. Examples of the mercapto-substituted heteroaromatic compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2-mercapto-5-methylbenzimidazole, 6-ethoxy-
2-mercaptobenzothiazole, 2,2′-dithiobis- (benzothiazole), 3-mercapto-1,2,2
4-triazole, 4,5-diphenyl-2-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-
4 (3H) -quinazolinone, 7-trifluoromethyl-
4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4 -Thiadiazole, 3
-Amino-5-mercapto-1,2,4-triazole, 4-hydrochirocy-2-mercaptopyrimidine, 2-
Mercaptopyrimidine, 4,6-diamino-2-mercaptopyrimidine, 2-mercapto-4-methylpyrimidine hydrochloride, 3-mercapto-5-phenyl-
1,2,4-triazole, 1-phenyl-5-mercaptotetrazole, 3- (5-mercaptotetrazole) -sodium benzenesulfonate, N-methyl-
Examples include N ′-{3- (5-mercaptotetrazolyl) phenyl} urea, 2-mercapto-4-phenyloxazole, and the like, but the invention is not limited thereto. The addition amount of these mercapto compounds is preferably in the range of 0.0001 to 1.0 mol per mol of silver in the image forming layer, and more preferably 0.001 to 0.3 mol per mol of silver. It is.

The heat-developable image recording material of the present invention has, on a support, an image forming layer containing an organic silver salt, a reducing agent and a photosensitive silver halide, and at least one protective layer on the image forming layer. Preferably, a layer is provided. Further, the image recording material of the present invention preferably has at least one back layer on the side (back surface) opposite to the image forming layer with respect to the support, and serves as a binder for the image forming layer, the protective layer, and the back layer. Polymer latex is used. By using a polymer latex for these layers, aqueous coating using a solvent (dispersion medium) containing water as a main component becomes possible, which is advantageous in terms of environment and cost, and causes wrinkles during thermal development. A heat-developable image recording material can be obtained. Further, by using a support which has been subjected to a predetermined heat treatment, a photothermographic material having a small dimensional change before and after thermal development can be obtained.

It is preferable to use the polymer latex described below as the binder used in the present invention. It is preferable that at least one of the image forming layers containing the photosensitive silver halide of the image recording material of the present invention is an image forming layer using the polymer latex described below in an amount of 50% by mass or more of the total binder. The polymer latex may be used not only for the image forming layer but also for the protective layer and the back layer. In particular, when the image recording material of the present invention is used for printing in which dimensional change is a problem, the protective layer or the back layer may be used. It is also preferable to use a polymer latex. However, the "polymer latex" referred to here is a polymer in which a water-insoluble hydrophobic polymer is dispersed as fine particles in a water-soluble dispersion medium. The dispersion state is such that the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or partially dispersed in polymer molecules and the molecular chains themselves are molecularly dispersed. Any of them may be used. The polymer latex used in the present invention is described in "Synthetic Resin Emulsion (edited by Tadashi Okuda and Hiroshi Inagaki, published by Polymer Publishing Association (1978))", "Application of Synthetic Latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Keiji Kasahara) , Published by the Society of Polymer Publishing (1993)), "Synthesis of Synthetic Latex (Souichi Muroi, published by the Society of Polymer Publishing (197)
0))). The average particle size of the dispersed particles is 1 to 50,000 nm, more preferably 5 to 1000 nm.
The range of the degree is preferable. The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution.

The polymer latex used in the present invention may be a so-called core / shell type latex other than the polymer latex having a normal uniform structure. In this case, it may be preferable to change the glass transition temperature of the core and the shell. The glass transition temperature (Tg) of the polymer latex preferably used for the binder used in the present invention differs between the protective layer, the back layer and the image forming layer. In the image forming layer, the temperature is preferably from -30 to 40 ° C. in order to promote diffusion of the photographically useful material during thermal development. When used for the protective layer or the back layer, a glass transition temperature of 25 to 70 ° C. is preferable for contacting various devices. The minimum film formation temperature (MFT) of the polymer latex used in the present invention is-
30 ° C to 90 ° C, more preferably about 0 ° C to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. The film forming aid is an organic compound (usually an organic solvent) which is also called a plasticizer and lowers the minimum film forming temperature of the polymer latex. ) "
It is described in.

The polymer used in the polymer latex used in the present invention includes acrylic resin, vinyl acetate resin, polyester resin, polyurethane resin, rubber resin, vinyl chloride resin, vinylidene chloride resin, polyolefin resin, or a copolymer thereof. And the like.
The polymer may be a linear polymer, a branched polymer, or a crosslinked polymer. The polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized. In the case of a copolymer, it may be a random copolymer or a block copolymer. The number average molecular weight of the polymer is preferably 5,000 to 1,000,000, and more preferably 10,000 to 100,000. If the molecular weight is too small, the mechanical strength of the image forming layer is insufficient, and if it is too large, the film-forming properties are poor, which is not preferable.

Specific examples of the polymer latex used as a binder in the image forming layer of the image recording material of the present invention include methyl methacrylate / ethyl acrylate /
Latex of methacrylic acid copolymer, latex of methyl methacrylate / butadiene / itaconic acid copolymer, latex of ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer, styrene / butadiene / acrylic acid copolymer Latex, styrene / butadiene / divinylbenzene / methacrylic acid copolymer latex, methyl methacrylate / vinyl chloride / acrylic acid copolymer latex, vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer latex, and the like. More specifically, methyl methacrylate / ethyl acrylate / methacrylic acid = 33.5 /
50 / 16.5 (% by mass) copolymer latex, methyl methacrylate / butadiene / itaconic acid = 47.
5 / 47.5 / 5 (wt%) copolymer latex,
Ethyl acrylate / methacrylic acid = 95/5 (% by mass) copolymer latex. Also,
Such polymers are also commercially available, for example, Sebian A-4635,4658 as an example of an acrylic resin.
3, 4601 (all manufactured by Daicel Chemical Industries, Ltd.), Ni
pol LX811, 814, 821, 820, 857
(Nippon Zeon Co., Ltd.), VONCORT-R33
As polyester resins such as 40, R3360, R3370, 4280 (all manufactured by Dainippon Ink and Chemicals, Inc.), FINETEX ES650, 611, 675, 8
50 (all manufactured by Dainippon Ink and Chemicals, Inc.), WD-siz
e, WMS (all manufactured by Eastman Chemical Co., Ltd.) such as HYDRAN AP10, 20,
Rubber-based resins such as 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.) include LACSTAR 7310K, 330
7B, 4700H, 7132C (all manufactured by Dainippon Ink and Chemicals, Inc.), Nipol LX410, 430, 43
5, 438C (manufactured by Nippon Zeon Co., Ltd.), vinyl chloride resins such as G351 and G576 (manufactured by Nippon Zeon Co., Ltd.), and vinylidene chloride resin, L50
2, L513 (all made by Asahi Kasei Corporation), Aron D7
020, D504, D5071 (Mitsui Toatsu Co., Ltd.
Chemical Pearl S12 as an olefin resin
And SA100 (all manufactured by Mitsui Petrochemical Co., Ltd.). These polymers may be used alone or as a mixture of two or more as necessary.

The image forming layer contains 50% by mass of the total binder.
As the above, the polymer latex is preferably used, and it is more preferable that the polymer latex is used at 70% by mass or more. If necessary, a hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, or hydroxypropylmethylcellulose may be added to the image forming layer in a range of 50% by mass or less of the whole binder. The addition amount of these hydrophilic polymers is 30% by mass or less of the total binder in the image forming layer,
Further, the content is preferably 15% by mass or less.

The image forming layer is preferably prepared by applying an aqueous coating solution and then drying. However, the term “aqueous” as used herein means that 60% by mass or more of the solvent (dispersion medium) of the coating liquid is water. Components other than water in the coating solution are methyl alcohol, ethyl alcohol, isopropyl alcohol,
Water-miscible organic solvents such as methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used. Specific examples of the solvent composition include the following. Water / methanol = 90/10, water / methanol = 70/30, water / ethanol = 90/10,
Water / isopropanol = 90/10, water / dimethylformamide = 95/5, water / methanol / dimethylformamide = 80/15/5, water / methanol / dimethylformamide = 90/5/5. (The numbers represent mass%.) The total amount of binder in the image forming layer is 0.2 to 30 g / m ² ,
More preferably, the range is 1 to 15 g / m ² . A crosslinking agent for crosslinking and a surfactant for improving coating properties may be added to the image forming layer. Further, as a binder for the protective layer, polymer latexes having different I / O values obtained by dividing an inorganic value by an organic value based on an organic conceptual diagram described in paragraph Nos. 0025 to 0029 of Japanese Patent Application No. 11-6872. Can be preferably used.

In the present invention, if necessary, Japanese Patent Application No.
Paragraph Nos. 0021 to 002 of the specification of 1-114358
5 plasticizer (eg, benzyl alcohol, 2,2,
Addition of 4-trimethylpentanediol-1,3-monoisobutyrate) can control the film formation temperature. Further, as described in paragraphs 0027 to 0028 of Japanese Patent Application No. 11-6872, a hydrophilic polymer may be added to a polymer binder, and a water-miscible organic solvent may be added to a coating solution. Each layer is described in
000-19678, paragraph numbers 0023-004
The first polymer latex into which the functional group described in 1 is introduced, a crosslinking agent having a functional group capable of reacting with the first polymer latex, and / or the second polymer latex can also be used.

The above-mentioned functional groups include carboxyl group, hydroxyl group, isocyanate group, epoxy group, N-methylol group, oxazolinyl group and the like. As crosslinking agents, epoxy compounds, isocyanate compounds, blocked isocyanate compounds, methylol compounds, Hydroxy compounds,
It is selected from carboxyl compounds, amino compounds, ethyleneimine compounds, aldehyde compounds, halogen compounds and the like. Specific examples of the cross-linking agent include hexamethylene isocyanate and duranate WB as isocyanate compounds.
40-80D, WX-1741 (Asahi Kasei Corporation)
Manufactured by Sumitomo Bayer Urethane Co., Ltd.), Takenate WD725 (manufactured by Takeda Pharmaceutical Co., Ltd.), Aquanate 100, 200 (manufactured by Nippon Polyurethane Co., Ltd.), described in JP-A-9-160172. Water-dispersed polyisocyanate; Sumitex Resin M-3 (manufactured by Sumitomo Chemical Co., Ltd.) as an amino compound; Denacol EX-614B (manufactured by Nagase Kasei Kogyo Co., Ltd.) as an epoxy compound; 2,4-dichloro- as a halogen compound 6-hydroxy-1,3,5-triazine sodium and the like.

The total amount of the binder for the image forming layer is from 0.2 to
30 g / m ^2, more preferably in the range of 1.0~15g / m ^2. The total binder amount for the protective layer is 0.2 to 1
0.0 g / m ² , more preferably 0.5 to 6.0 g / m ²
Is preferable. The total amount of binder for the back layer is 0.
01 to 10.0 g / m ² , more preferably 0.05 to
A range of 5.0 g / m ² is preferred.

Each of these layers may be provided in two or more layers. When there are two or more image forming layers, it is preferable to use a polymer latex as a binder for all the layers. Further, the protective layer is a layer provided on the image forming layer, and may have two or more layers.
Preferably, a polymer latex is used for the layer, especially the outermost protective layer. The back layer is a layer provided on the undercoat layer on the back surface of the support, and there may be two or more layers. However, it is preferable to use a polymer latex for at least one layer, particularly the outermost back layer.

In the heat-developable image recording material of the present invention, a slip agent can be used. The slip agent referred to in this specification is
When present on the surface of an object, it means a compound that reduces the coefficient of friction on the surface of the object as compared to the case where it is not present. The type is not particularly limited. Examples of the slip agent used in the present invention include paragraph 006 of JP-A-11-84573.
1 to 0064, and the compounds described in Paragraph Nos. 0049 to 0062 of Japanese Patent Application No. 11-106881. Specific examples of preferred slip agents include Cellolsol 524 (main component carnauba wax), Polylon A, 3
93, H-481 (main component polyethylene wax), Himicron G-110 (main component ethylenebisstearic acid amide), Himicron G-270 (main component stearic acid amide) (all manufactured by Chukyo Yushi Co., Ltd.), such as _{W-1 C 16 H 33 -O} -SO 3 Na W-2 C 18 H 37 -O-SO 3 Na and the like. The amount of the slip agent used is 0.1 to 50% by mass of the binder amount of the additive layer, preferably 0.5 to 50% by mass.
30% by mass.

In the present invention, JP-A-2000-1719
No. 35, the pre-heating unit is conveyed by a facing roller as described in Japanese Patent Application No. 11-106881, and the heat development processing unit drives the roller having the image forming layer on the side having the image forming layer.
In the case of using a heat development processing apparatus which conveys the opposite back surface by sliding it to a smooth surface, the outermost surface layer on the side having the image forming layer of the heat development image recording material at the development processing temperature and the outermost surface layer on the back surface Is 1.5 or more, and there is no particular upper limit, but it is about 30. Further, μb is 1.0 or less, preferably 0.05 to 0.8. This value is obtained by the following equation. Ratio of friction coefficient = dynamic friction coefficient (μe) between roller member of heat developing machine and surface having image forming layer / dynamic friction coefficient (μb) of smooth surface member and back surface of heat developing machine (heat) The lubricating property of the outermost surface layer on the surface having the heat development processing machine member and the image forming layer and / or the opposite surface thereof can be adjusted by including a slipping agent in the outermost surface layer and changing the amount of addition. it can.

On both sides of the support, JP-A-64-2054
No. 4, JP-A-1-180537, JP-A-1-18037
No. 209443, JP-A-1-285939,
JP-A-1-296243, JP-A-2-24649
JP, JP-A-2-24648, JP-A-2-18
4844, JP-A-3-109545, JP-A-3-137637, JP-A-3-141346, JP-A-3-141347, JP-A-4-96
No. 055, U.S. Pat. No. 4,645,731, Japanese Unexamined Patent Publication No. 4-68344, and Japanese Patent No. 2,557,
No. 641, page 2, right column, line 20 to page 3, right column, line 30;
Paragraph No. 0020 of JP-A-2000-39684
It is preferable to provide an undercoat layer containing a vinylidene chloride copolymer containing 70% by mass or more of vinylidene chloride monomer repeating units described in paragraphs 0063 to 0080 of Japanese Patent Application No. 11-106881.

When the amount of the vinylidene chloride monomer is less than 70% by mass, sufficient moisture-proof properties cannot be obtained, and the dimensional change over time after thermal development becomes large. Further, the vinylidene chloride copolymer preferably contains a repeating unit of a carboxyl group-containing vinyl monomer as another constituent repeating unit of the vinylidene chloride monomer. It is only vinyl chloride monomer that contains such a repeating unit.
The polymer (polymer) is crystallized, making it difficult to form a uniform film when applying a moisture-proof layer. In addition, a carboxyl group-containing vinyl monomer is indispensable for stabilizing the polymer (polymer). Because there is. The vinylidene chloride copolymer used in the present invention has a weight average molecular weight of 45.0.
00 or less, and more preferably 10,000 to 45,000. When the molecular weight is increased, the adhesiveness between the vinylidene chloride copolymer layer and a support layer such as polyester tends to deteriorate.

The content of the vinylidene chloride copolymer used in the present invention is 0.3 μm or more as a total film thickness per one side of the undercoat layer containing the vinylidene chloride copolymer.
Preferably, it is in the range of 0.3 μm to 4 μm. The vinylidene chloride copolymer layer as the undercoat layer is preferably provided as the first undercoat layer directly provided on the support. Usually, one layer is provided on each side, but in some cases, two layers are provided. The above may be provided. When a multi-layer structure of two or more layers is used, the total amount of the vinylidene chloride copolymer may fall within the range of the present invention. Such a layer may contain a crosslinking agent, a matting agent, and the like in addition to the vinylidene chloride copolymer. The support may be coated, if necessary, with an undercoat layer using SBR, polyester, gelatin or the like as a binder, in addition to the vinylidene chloride copolymer layer. These undercoat layers may have a multilayer structure or may be provided on one side or both sides of the support. Thickness of undercoat layer (1
(Per layer) is generally between 0.01 and 5 μm, more preferably between 0.05 and 1 μm.

Various supports can be used for the image recording material of the present invention. Typical supports include polyesters such as polyethylene terephthalate and polyethylene naphthalate, cellulose nitrate, cellulose ester, polyvinyl acetal, syndiotactic polystyrene, polycarbonate, and paper supports coated on both sides with polyethylene. Among them, biaxially stretched polyester, especially polyethylene terephthalate (P
ET) is preferred in terms of strength, dimensional stability, chemical resistance and the like. The thickness of the support was 9 as the base thickness excluding the undercoat layer.
It is preferably from 0 to 180 μm. As the support used in the image recording material of the present invention, JP-A-10-4877
No. 2, JP-A-10-10676, JP-A-10-10676
-10677, JP-A-11-65025,
In order to alleviate the internal strain remaining in the film at the time of biaxial stretching described in JP-A-11-138648 and to eliminate the heat shrinkage strain generated during the heat development process, 130 to 18
Polyester, particularly polyethylene terephthalate, which has been subjected to a heat treatment in a temperature range of 5 ° C. is preferably used. The dimensional change rate of the support after heating at 120 ° C. for 30 seconds after the heat treatment is −0.03% to + in the machine direction (MD).
Preferably, it is 0.01% and the transverse direction (TD) is 0 to 0.04%.

The image recording material of the present invention is disclosed in JP-A-11-84573, paragraphs [0040] to [0051], for the purpose of reducing adhesion of dust, preventing the occurrence of static marks, and preventing conveyance failure in an automatic conveyance process. The antistatic property can be achieved by using the above-described conductive metal oxide and / or fluorine-based surfactant. As the conductive metal oxide, US Pat. No. 5,575,957, JP-A-11-223
No. 901 described in paragraphs 0012 to 0020 are preferably used as acicular conductive tin oxide doped with antimony and fibrous tin oxide doped with antimony described in JP-A-4-29134.

The surface resistivity (surface resistivity) of the metal oxide-containing layer is 10 ¹² Ω or less, preferably 10 ¹¹ Ω or less in an atmosphere at 25 ° C. and a relative humidity of 20%. Thereby, good antistatic properties can be obtained. The lower limit of the surface resistivity at this time is not particularly limited, but is usually about 10 ⁷ Ω.

At least one of the surface having the image forming layer of the image recording material of the present invention and the outermost layer surface opposite to the surface having the image forming layer,
Preferably, both Beck smoothness are less than or equal to 2000 seconds, more preferably between 10 seconds and 2000 seconds. The Beck smoothness in the present invention is based on Japanese Industrial Standard (JIS) P8
119 can be easily obtained according to “Test method for smoothness of paper and paperboard using a Beck tester” and TAPPI standard method T479. The Beck smoothness of the outermost layer on the surface having the image forming layer of the image recording material and the outermost layer on the opposite surface are described in paragraph No. 0052 of JP-A-11-84573.
As described in -0059, it can be controlled by appropriately changing the particle size and the amount of the matting agent contained in the layers on both sides.

In the present invention, a water-soluble polymer is preferably used as a thickener for imparting coatability, and may be a natural product or a synthetic polymer, and the type thereof is not particularly limited. Specifically, as natural products, starches (corn starch,
Starch, etc.), seaweed (agar, sodium alginate, etc.), vegetable glue (gum arabic, etc.), animal protein (glue, casein, gelatin, egg white, etc.), fermented glue (pullulane, dextrin, etc.), etc. Semi-synthetic polymers such as starchy materials (soluble starch, carboxyl starch, dextran, etc.) and celluloses (viscose, methylcellulose, ethylcellulose,
Carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, etc.), and synthetic polymers (polyvinyl alcohol, polyacrylamide,
Polyvinyl pyrrolidone, polyethylene glycol, polypropylene glycol, polyvinyl ether, polyethylene imine, polystyrene sulfonic acid or its copolymer, polyvinyl sulfanic acid or its copolymer, polyacrylic acid or its copolymer, acrylic acid or its copolymer Maleic acid copolymer, maleic acid monoester copolymer, acryloylmethylpropanesulfonic acid or a copolymer thereof).

Among these, water-soluble polymers preferably used include sodium alginate, gelatin, dextran, dextrin, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone, polyethylene glycol, polypropylene glycol, Polystyrene sulfonic acid or its copolymer, polyacrylic acid or its copolymer, maleic acid monoester copolymer, acryloylmethylpropane sulfonic acid or its copolymer, and the like are particularly preferably used as a thickener.
Particularly preferred thickeners among these are gelatin, dextran, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone,
Examples include polystyrene sulfonic acid or its copolymer, polyacrylic acid or its copolymer, and maleic acid monoester copolymer. These compounds are described in detail in "Applications and Markets of New Water-Soluble Polymers" (published by CMC Corporation, edited by Shinji Nagatomo, issued on November 4, 1988).

The amount of the water-soluble polymer used as a thickener is not particularly limited as long as the viscosity increases when added to a coating solution. Generally, the concentration in the liquid is 0.01 to 30% by mass, more preferably 0.05 to 20% by mass, and particularly preferably 0.1 to 10% by mass. The viscosity obtained by these methods is 1 to 200 mPa as an increase from the initial viscosity.
S is preferred, and more preferably 5 to 100 mPa · s
It is. The viscosity is a value measured at 25 ° C. with a B-type rotational viscometer. When adding to a coating solution or the like, it is generally desirable to add the thickener in a solution as dilute as possible. In addition, it is preferable to perform sufficient stirring during the addition.

The surfactant used in the present invention will be described below. Surfactants used in the present invention are classified into dispersants, coating agents, wetting agents, antistatic agents, photographic control agents, and the like depending on the purpose of use, and the surfactants described below are appropriately selected and used. These objectives can be achieved by doing so. The surfactant used in the present invention may be either nonionic or ionic (anion, cation, betaine). Further, a fluorine-based surfactant is also preferably used.

Preferred nonionic surfactants include:
Polyoxyethylene, polyoxypropylene, polyoxybutylene, polyglycidyl and a surfactant having a nonionic hydrophilic group of sorbitan can be mentioned. Specifically, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether Polyoxyethylene-polyoxypropylene glycol, polyhydric alcohol fatty acid partial ester, polyoxyethylene polyhydric alcohol fatty acid partial ester, polyoxyethylene fatty acid ester, polyglycerin fatty acid ester, fatty acid diethanolamide, and triethanolamine fatty acid partial ester. be able to.

Examples of the anionic surfactant include carboxylate, sulfate, sulfonate and phosphate ester, and typical examples are fatty acid salt, alkylbenzene sulfonate and alkylnaphthalenesulfonic acid. Salt, alkyl sulfonate, α-olefin sulfonate, dialkyl sulfosuccinate, α-sulfonated fatty acid salt, N-methyl-N-oleyltaurine, petroleum sulfonate, alkyl sulfate, sulfated oil, polyoxy Examples include ethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate, polyoxyethylene styrenated phenyl ether sulfate, alkyl phosphate, polyoxyethylene alkyl ether phosphate, and naphthalene sulfonate formaldehyde condensate. Can be. Examples of the cationic surfactant include amine salts, quaternary ammonium salts, pyridium salts, and the like. Primary to tertiary fatty amine salts, quaternary ammonium salts (tetraalkylammonium salts, trialkylbenzylammonium salts, Alkylpyridium salts, alkylimidazolium salts, etc.).

Examples of the betaine-based surfactant include carboxybetaine and sulfobetaine.
-Trialkyl-N-carboxymethylammonium betaine, N-trialkyl-N-sulfoalkyleneammonium betaine and the like. These surfactants are described in "Applications of Surfactants" (written by Koshobo and Takao Karimei, published on September 1, 1980). In the present invention, a preferred surfactant is not particularly limited in its use amount, and any surfactant may be used as long as desired surfactant properties can be obtained. In addition, the application amount of the fluorine-containing surfactant is preferably 0.01 mg to 250 mg per 1 m ² .

Specific examples of the surfactant are described below, but are not limited thereto (here, -C ₆ H _4- represents a phenylene group). _{WA-1: C 16 H 33} (OCH 2 CH 2) 10 OH WA-2: C 9 H 19 -C 6 H 4 - (OCH 2 CH 2) 12 OH WA-3: sodium dodecylbenzene sulfonate WA-4 : Sodium tri (isopropyl) naphthalenesulfonate WA-5: sodium tri (isobutyl) naphthalenesulfonate WA-6: sodium dodecyl sulfate WA-7: sodium salt of α-sulfosuccinic acid di (2-ethylhexyl) ester WA-8: C _{8 H 17 -C 6 H 4 -} (CH 2 CH 2 O) 3 (CH 2) 2 SO 3 K WA-10: cetyltrimethylammonium chloride _{WA-11: C 11 H 23} CONHCH 2 CH 2 N (+) ( CH ₃ ) ₂ -CH ₂ COO ^(-) WA-12: C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ CH ₂ O) ₁₆ H WA-13: C ₈ F ₁₇ SO ₂ N (C _{3 H 7) CH 2 COOK WA} -14: C 8 F 17 SO 3 K WA-15: C 8 F 17 SO 2 N (C 3 H 7) (CH 2 CH 2 O) 4 (CH 2) 4 SO 3 Na WA-16: C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ ) ₃ OCH ₂ CH ₂ N ⁽⁺⁾ (C
H ₃ ) ₃ -CH ₃ · C ₆ H ₄ -SO ₃ ^(-) WA-17: C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) CH ₂ CH ₂ CH ₂ N ⁽⁺⁾ (CH ₃ ) ₂ -C
H ₂ COO ^(-)

In a preferred embodiment of the present invention, an intermediate layer may be provided, if necessary, in addition to the image forming layer and the protective layer. For the purpose of improving productivity and the like, it is preferable that these multiple layers are simultaneously coated in an aqueous system. The coating method includes extrusion coating, slide bead coating, curtain coating, and the like.
The slide bead coating method shown in FIG. In the case of a silver halide photographic material using gelatin as a main binder, the material is rapidly cooled in a first drying zone provided downstream of a coating die, and as a result, gelatinization of gelatin occurs and the coating film is cooled and solidified. . The coating film that has been cooled and solidified and has stopped flowing is guided to the subsequent second drying zone, where the solvent in the coating solution is volatilized and formed into a film in the subsequent drying zone. As a drying method after the second drying zone, an air loop method in which a jet is blown from a U-shaped duct to a roller-supported support, or a support in which the support is wound around a cylindrical duct in a helical shape, and conveyed and dried. A fire method (air floating method) and the like can be mentioned. When a layer is formed using a coating liquid in which the main component of the binder is a polymer latex, the flow of the coating liquid cannot be stopped by rapid cooling, so that the preliminary drying may be insufficient only in the first drying zone. . In this case, a drying method such as that used for a silver halide photographic light-sensitive material causes flow unevenness and drying unevenness, and easily causes a serious defect in the coated surface.

The preferred drying method in the present invention is a horizontal drying method at least until the constant-rate drying is completed, regardless of the first drying zone or the second drying zone as described in JP-A-2000-2964. This is a method of drying in a drying zone. The transfer of the support from the time immediately after the coating until the support is guided to the horizontal drying zone may or may not be horizontal, and the rising angle of the coating machine with respect to the horizontal direction may be between 0 and 70 °. In addition, the horizontal drying zone in the present invention only needs to be conveyed within ± 15 ° up and down with respect to the horizontal direction of the coating machine, and does not mean horizontal conveyance.

The constant-rate drying in the present invention means a drying process in which the liquid film temperature is constant and all the heat flowing in is used for evaporating the solvent. At the end of drying, the rate of drying decreases at the end of drying due to various factors (such as the rate of diffusion of the material inside the material that controls the movement of water and the retreat of the evaporation surface), and the applied heat is also used to raise the liquid film temperature. Drying process. The critical water content at which the transition from the constant rate process to the rate reduction process is 200-3
00%. When constant-rate drying is completed, drying proceeds sufficiently until the flow stops, and a drying method such as a silver halide photographic light-sensitive material can also be employed. It is preferable to dry in a horizontal drying zone up to the drying point. The drying conditions when forming the image forming layer and / or the protective layer are such that the liquid film surface temperature during constant rate drying is the minimum film forming temperature (MT) of the polymer latex.
F; usually 3-5 ° C. higher than the glass transition temperature Tg of the polymer). Usually, the temperature is often set to 25 ° C. to 40 ° C. due to the limitation of manufacturing equipment. Further, the dry-bulb temperature during the rate-decreasing drying is preferably a temperature lower than the Tg of the support (usually 80 ° C. or lower in the case of PET). The liquid film surface temperature in this specification refers to the solvent liquid film surface temperature of the coating liquid film applied to the support, and the dry bulb temperature refers to the temperature of the drying air in the drying zone. When the drying is performed under the condition that the liquid film surface temperature during the constant-rate drying is low, the drying tends to be insufficient. For this reason, particularly, the film forming property of the protective layer is significantly reduced, and cracks are easily generated on the film surface. In addition, the film strength is weakened, and serious problems such as susceptibility to damage during transport in an exposure machine or a heat developing machine are likely to occur.

On the other hand, when dried under the condition that the liquid film surface temperature becomes high, the protective layer mainly composed of polymer latex quickly forms a film, while the lower layer such as the image forming layer has fluidity. Since the surface is not stopped, irregularities are likely to be generated on the surface. Further, when an excessive heat higher than Tg is applied to the support (base), the dimensional stability and the curl resistance of the photosensitive material tend to deteriorate. The same applies to the sequential coating in which the lower layer is applied and then dried and then the upper layer is applied. The pH difference between the coating solution for the image forming layer and the coating solution for the protective layer is preferably 2.5 or less, and the smaller the pH difference, the better. When the pH difference of the coating solution is large, micro-aggregation is likely to occur at the interface of the coating solution, and a serious surface failure such as a coating streak is likely to occur during long continuous coating.

The coating liquid viscosity of the image forming layer is 15 to 25 ° C.
100 mPa · s is preferred, and more preferably 30 to
70 mPa · s. On the other hand, the coating liquid viscosity of the protective layer is 2
The temperature is preferably 5 to 75 mPa · s at 5 ° C., and more preferably 20 to 50 mPa · s. These viscosities are measured by a B-type viscometer. Winding after drying is 20 ~
It is preferable to carry out under the conditions of 30 ° C. and a relative humidity of 45 ± 20%, and the winding form may be on the image forming layer side outside or on the inside depending on the subsequent processing form. Further, when the processing form is a roll product, it is also preferable to use a roll form wound on the side opposite to the winding form at the time of processing in order to remove the curl generated in the winding form. It is preferable that the relative humidity of the photosensitive material is controlled in the range of 20 to 55% (measured at 25 ° C.).

In a conventional photographic emulsion coating solution which is a viscous solution containing a silver halide and containing a silver halide, bubbles are dissolved and disappear in the solution simply by sending the solution under pressure. Even when returned, there is almost no bubble deposition. However, in the case of an image forming layer coating solution containing an organic silver salt dispersion and a polymer latex, which are preferably used in the present invention, the defoaming tends to be insufficient only by pressurized liquid feeding, so that a gas-liquid interface does not occur. It is preferable to remove the bubbles by applying ultrasonic vibration while feeding the solution. In the present invention, the defoaming of the coating liquid is performed by deaeration under reduced pressure before the coating liquid is applied, and further, while maintaining the pressurized state of 1.5 kg / cm ² or more, and without generating a gas-liquid interface. It is preferable to apply ultrasonic vibration while feeding the liquid to the container. Specifically, the method described in JP-B-55-6405 (page 4, line 20 to page 7, line 11) is preferable. As an apparatus for performing such defoaming, an apparatus shown in the embodiment of JP-A-2000-98534 and the apparatus shown in FIG. 3 can be preferably used.

The pressure is preferably 1.5 kg / cm ² or more, more preferably 1.8 kg / cm ² or more. There is no particular upper limit, but usually 5 kg / cm ²
It is about. The applied ultrasonic sound pressure is 0.2V or more,
The sound pressure is preferably 0.5 V to 3.0 V, and in general, it is preferable that the sound pressure be high. However, if the sound pressure is too high, the temperature becomes partially high due to caption, which causes fogging. The frequency is not particularly limited, but is usually 10 kHz or more,
Preferably, it is 20 kHz to 200 kHz. In addition, decompression degassing refers to deaeration by increasing the bubble diameter in the coating solution, increasing the buoyancy, and deaeration by reducing the pressure inside the tank (usually a liquid preparation tank or a storage tank). Depressurization conditions are -200 mmHg or lower pressure conditions,
The pressure condition is preferably -250 mmHg or lower, and the lowest pressure condition is not particularly limited, but is usually about -800 mmHg. Decompression time is 30 minutes or more,
It is preferably 45 minutes or more, and the upper limit is not particularly limited.

In the present invention, the image forming layer, the protective layer of the image forming layer, the undercoat layer and the back layer are described in JP-A-11-84.
No. 573, paragraphs 0204 to 0208, Japanese Patent Application No.
Paragraph Nos. 0240 to 024 of 1-106881 specification
A dye can be contained for the purpose of preventing halation as described in 1. Various dyes and pigments can be used in the image forming layer from the viewpoints of color tone improvement and irradiation prevention. Although any dyes and pigments can be used for the image forming layer, see, for example, JP-A-11-11937.
The compound described in paragraph No. 0297 of JP-A No. 4 can be used. As a method of adding these dyes,
Any method such as a solution, an emulsion, a dispersion of solid fine particles, and a state in which it is mordanted with a polymer mordant may be used. The amount of these compounds to be used is determined depending on the desired absorption amount, but it is generally preferable to use them in the range of 1 × 10 ⁻⁶ g to 1 g per 1 m ² . When an antihalation dye is used in the present invention, the dye has a desired absorption in a desired range, has a sufficiently low absorption in the visible region after the treatment, and has a desired absorbance spectrum shape of the back layer. It may be a compound. For example, a compound described in paragraph No. 0300 of JP-A-11-119374 can be used. Further, as described in Belgian Patent No. 733,706, a method in which the concentration of a dye is reduced by discoloration by heating, or by discoloration by light irradiation as described in JP-A-54-17833. A method of reducing the concentration and the like can also be used.

When the heat-developable image-recording material of the present invention is used as a mask when preparing a printing plate using a PS plate after heat-development, the heat-developable image-recording material after heat development is applied to a PS plate by a plate making machine. Information for setting exposure conditions and information for setting plate making conditions such as mask original and PS plate transfer conditions are carried as image information. Therefore, the concentration (use amount) of the irradiation dye, the halation dye, and the filter dye is limited in order to read them. Since such information is read by an LED or a laser, Dmin (minimum concentration) in the wavelength range of the sensor needs to be low, and the absorbance needs to be 0.3 or less. For example, a plate making machine S-FNRIII manufactured by Fuji Photo Film Co., Ltd. has a 670 nm as a detector and a barcode reader for detecting a register mark.
The light source of the wavelength is used. Also, as a bar code reader for the plate making machine APML series manufactured by Shimizu Seisakusho,
A 0 nm light source is used. That is, when Dmin (minimum density) around 670 nm is high, information on the film cannot be detected accurately, and a work error such as a conveyance failure or an exposure failure occurs in a plate making machine. Therefore, in order to read information with a 670 nm light source, Dmin around 670 nm needs to be low, and the absorbance at 660 to 680 nm after thermal development needs to be 0.3 or less. More preferably 0.25
It is as follows. Although the lower limit is not particularly limited, it is usually 0.1.
It is about 10.

In the present invention, any exposure apparatus used for imagewise exposure may be used as long as it can perform exposure with an exposure time of 10 ^-7 seconds or less. An exposure apparatus using (LED) as a light source is preferably used. In particular, LD has high output,
More preferable in terms of high resolution. Any of these light sources may be used as long as it can generate light of an electromagnetic wave spectrum in a target wavelength range. For example, in the case of LD, a dye laser, a gas laser, a solid laser, a semiconductor laser, or the like can be used. In particular, a semiconductor laser is preferable, and specific examples thereof include In1-x Gax P (to
700 nm), GaAs1-x Px (610-900 n)
m), Ga1-x Alx As (690-900 nm), I
nGaAsP (1100-1670 nm) AlGaAs
A semiconductor laser using a material such as Sb (1250 to 1400 nm) is given. Irradiation of light to the color photosensitive material in the present invention may be a YAG laser (1064 nm) that excites a Nb: YAG crystal with a GaAsx P (1-x) light emitting diode, in addition to the above semiconductor laser. Preferably, 670, 680, 750,
It is preferable to select from 780, 810, 830, and 880 nm semiconductor laser beams.

In the present invention, the second harmonic generation element (SHG element) converts the wavelength of a laser beam to one half by applying a nonlinear optical effect. Examples include those using CD * A and KD * P (Laser Handbook, edited by The Laser Society of Japan, published December 15, 1982, pages 122 to 13).
See page 9.) It is also possible to use a LiNbO3 optical waveguide element in which an optical waveguide in which Li + is ion-exchanged with H + in a LiNbO3 crystal is formed (NIKKEIELECT).
RONICS 1986.7.14 (No. 399) pp. 89-90). In the present invention, JP-A-63-22655 is disclosed.
The output device described in the specification of No. 2 can be used.

The exposure is performed by overlapping the light beams of the light source. Overlap means that the sub-scanning pitch width is smaller than the beam diameter. The overlap can be quantitatively expressed by FWHM / sub-scanning pitch width (overlap coefficient), for example, when the beam diameter is represented by a half width of beam intensity (FWHM). In the present invention, the overlap coefficient is preferably 0.2 or more. The energy density at the time of exposure is several μJ / cm
It is preferably from ² to several hundred μJ / cm ² . Further, it is preferable that the number μJ / cm ² ~ number 10μJ / cm ^2S. The scanning method of the light source of the exposure apparatus used in the present invention is not particularly limited, and a cylinder outer surface scanning method, a cylinder inner surface scanning method, a plane scanning method, or the like can be used. The channel of the light source may be a single channel or a multi-channel, but in the case of a cylindrical outer surface type, a multi-channel is preferably used.

The image recording material of the present invention has a low haze at the time of exposure and tends to cause interference fringes. As a technique for preventing the occurrence of this interference fringe, a technique disclosed in Japanese Patent Application Laid-Open No. 5-113548, for example, in which a laser beam is obliquely incident on a photosensitive material, and a technique disclosed in International Publication WO 95/31754.
There is known a method using a multi-mode laser disclosed in, for example, Japanese Patent Application Laid-Open Publication No. H10-209, and it is preferable to use these techniques.

The heat development step of the image forming method using the image recording material of the present invention may be any method, but usually, the heat-developable image recording material exposed imagewise is heated and developed. A preferred embodiment of the heat developing machine used is a type in which the heat-developable image recording material is brought into contact with a heat source such as a heat roller or a heat drum.
No. 6499, Japanese Patent Application Laid-Open No. 9-292695, Japanese Patent Application Laid-Open No. 9-297385 and International Publication WO95 / 3.
Japanese Patent Application Laid-Open No. Hei 7-13294 as a non-contact type heat developing machine described in Japanese Patent Application Laid-open No.
JP-A-28489, JP-A-97 / 28488 and JP-A-97 / 28487 disclose a thermal developing machine. A particularly preferred embodiment is a non-contact type thermal developing machine. The preferred development temperature is 80 to 250C, more preferably 100 to 140C. The development time is 1
It is preferably from 180 to 180 seconds, more preferably from 5 to 90 seconds.
The line speed is preferably 140 cm / min or less.

As a method for preventing processing unevenness due to a dimensional change of the heat-developable image recording material during heat development, an image is not formed at a temperature of 80 ° C. or more and less than 115 ° C., and after heating for 5 seconds or more, 110 ° C. It is effective to employ a method of forming an image by heat development at a temperature of 140 ° C. (so-called multi-stage heating method). When the heat-developable image-recording material of the present invention is subjected to heat-development processing, it is exposed to a high temperature of 110 ° C. or more, so that a part of the components contained in the material or a part of the decomposed components by the heat development are volatilized. Come. These volatile components may cause uneven development, corrode the components of the heat developing machine, precipitate at low temperatures, cause deformation of the screen as foreign matter, and adhere to the screen and become dirty. Is known to have a bad effect. As a method for eliminating these effects, it is known to install a filter in the heat developing machine and optimally adjust the flow of air in the heat developing machine. These methods can be used effectively in combination.

International Publication Nos. WO95 / 30933, WO97 / 21150, and JP-T10-500496 disclose first and second openings for binding and introducing volatile components and volatile components. It is described that a filter cartridge having an opening is used as a heating device for heating in contact with a photothermographic material. In addition, international publication W
O96 / 12213, Tokuhyohei 10-507403
Japanese Patent Application Laid-Open Publication No. H11-176,086 describes that a filter combining a heat-conductive condensation collector and a gas-absorbing fine particle filter is used. In the present invention, these can be preferably used. U.S. Pat. No. 4,518,845 and JP-B-3-54331 disclose a device for removing vapor from a photothermographic material and a pressurizing device for pressing the photothermographic material against a heat transfer member. And a device for heating the heat transfer member. In addition, International Publication WO98 / 2
JP-A-7458 describes that a component which increases fog volatilized from the photothermographic material is removed from the surface of the photothermographic material. These can also be preferably used in the present invention.

FIG. 1 shows an example of the configuration of a heat developing machine used in the heat development of the heat-developable image recording material of the present invention. FIG. 1 is a side view of the heat developing machine. The heat developing machine of FIG. 1 carries in a pair of carry-in rollers 11 for carrying the heat-developable image recording material 10 into a heating section while correcting and preheating the heat-developable image recording material 10 (the upper roller is a silicon rubber roller and the lower roller is an aluminum heat roller). And a carry-out roller pair 12 for carrying out the heat-developed image recording material 10 from the heating unit while correcting the heat-developed image recording material 10 into a flat shape. The thermally developed image recording material 10 is thermally developed while being transported from the carry-in roller pair 11 to the carry-out roller pair 12. In the conveying means for conveying the heat-developable image recording material 10 during the heat development, a plurality of rollers 13 are provided on the side in contact with the surface having the image forming layer, and the non-woven fabric ( For example, a smooth surface 14 to which an aromatic polyamide or Teflon (registered trademark) is attached is provided. The heat-developable image recording material 10 is conveyed while the back surface is slid over the smooth surface 14 by driving a plurality of rollers 13 that come into contact with the surface having the image forming layer. Upper part of roller 13 and smooth surface 1
At the lower part of 4, a heater 15 is provided so as to be heated from both sides of the heat-developable image recording material 10. As a heating means in this case, a plate heater or the like can be used. Although the clearance between the roller 13 and the smooth surface 14 varies depending on the member of the smooth surface, the clearance is appropriately adjusted to allow the heat-developable image recording material 10 to be transported. Preferably 0 to 1 mm
It is.

Material of Roller 13 Surface and Smooth Surface 1
The member No. 4 is durable at high temperature and is a heat-developable image recording material 1
Any material may be used as long as it does not hinder the conveyance of 0, but the material of the roller surface is preferably silicone rubber, and the material of the smooth surface is preferably a nonwoven fabric made of aromatic polyamide or Teflon (PTFE).
It is preferable that a plurality of heaters be used as the heating means, and that the heating temperature be set freely. The heating unit includes a pre-heating unit A having the carry-in roller pair 11 and a heat development heating unit B including the heating heater 15. The pre-heating unit A upstream of the heat development processing unit B includes: It is desirable to set the temperature and time lower than the heat development temperature (for example, about 10 to 30 ° C.) and sufficient for evaporating the amount of water in the heat development image recording material 10. It is preferable to set the temperature at a temperature higher than the glass transition temperature (Tg) of the support so that development unevenness does not occur. The temperature distribution of the preheating section and the heat development processing section is ±
The temperature is preferably 1 ° C or lower, more preferably ± 0.5 ° C or lower.

A guide plate 16 is provided downstream of the thermal development processing section B, and a slow cooling section C having a pair of unloading rollers 12 and the guide plate 16 is provided. The guide plate 16 is preferably made of a material having a low thermal conductivity, and it is preferable to gradually cool the heat-developable image recording material 10 so that the heat-developable image recording material 10 is not deformed. Seconds are preferred. Although the description has been given with reference to the illustrated example, the invention is not limited to this example. In the case of the multi-stage heating method preferably used in the present invention, in the above-described apparatus, two or more heat sources having different heating temperatures may be provided, and heating may be performed continuously at different temperatures. Hereinafter, the present invention will be described more specifically with reference to examples. Materials, reagents, ratios, operations, and the like shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples.

[0104]

EXAMPLES Example 1 << Preparation of Silver Halide Emulsion A >> Alkali-treated gelatin (2700 ppm in terms of calcium content) was added to 700 ml of water.
The following) 11 g, 30 mg of potassium bromide and 1.3 g of sodium 4-methylbenzenesulfonate were dissolved, the pH was adjusted to 6.5 at a temperature of 40 ° C., and then 18.6 of silver nitrate.
g of aqueous solution, potassium bromide at 1 mol / l (NH ₄ ) ₂ RhCl ₅ (H ₂ O) at 5 × 10 ^-6 mol / l and K ₃ IrCl ₆ at 2 × 10 ^-5 mol / l. The aqueous solution containing the solution was added over 6 minutes and 30 seconds by the control double jet method while maintaining the pAg at 7.7. Then, 476 ml of an aqueous solution containing 55.5 g of silver nitrate, 1 mol / l of potassium bromide and 2 × 1 of K ₃ IrCl ₆ were added.
PAg halogen salt aqueous solution containing 0 ^-5 mol / l
Controlled by the double jet method while maintaining at 7.7
It was added over 8 minutes and 30 seconds. Thereafter, the pH was lowered to perform coagulation sedimentation and desalting treatment, and 51.1 g of low molecular weight gelatin having an average molecular weight of 15,000 (calculated as 20 ppm or less) was added to adjust the pH to 5.9 and pAg to 8.0. The obtained particles were cubic particles having an average particle size of 0.08 μm, a projected area variation coefficient of 9%, and a (100) plane ratio of 90%.

The silver halide grains thus obtained were heated to 60 ° C., and 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver, and after 3 minutes, 71 μmol of triethylthiourea was added, followed by aging for 100 minutes. After adding 5 × 10 ^-4 mol of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene and 0.17 g of compound A, the mixture was cooled to 40 ° C. Thereafter, the temperature was maintained at 40 ° C., and 4.7 × 10 ⁻² mol of potassium bromide (added as an aqueous solution) and 12.8 × 10 ⁻⁴ per mol of silver halide.
Moles of the following sensitizing dye A (added as an ethanol solution),
6.4 × 10 ⁻³ mol of compound B (added as a methanol solution) was added with stirring, and after 20 minutes, the mixture was rapidly cooled to 30 ° C. to complete the preparation of silver halide emulsion A.

[0106]

Embedded image

<< Preparation of Silver Behenate Dispersion A >> Behenic acid (Edenor C22-85R, manufactured by Henkel)
6 kg, 423 liters of distilled water, 49.2 liters of 5 mol / L NaOH aqueous solution, tert-butyl alcohol 1
Twenty liters were mixed and reacted by stirring at 75 ° C. for 1 hour to obtain a sodium behenate solution. Separately, silver nitrate 4
Prepare 206.2 liters of a 0.4 kg aqueous solution, and prepare 10
The temperature was kept at ℃. A reaction vessel containing 635 liters of distilled water and 30 liters of tert-butyl alcohol
While maintaining the temperature at 0 ° C. and stirring, the total amount of the sodium behenate solution and the total amount of the silver nitrate aqueous solution were each adjusted to 6 at a constant flow rate.
It was added over 2 minutes 10 seconds and 60 minutes. At this time, only the silver nitrate aqueous solution was added for 7 minutes and 20 seconds after the start of the silver nitrate aqueous solution addition, and then the sodium behenate solution was started to be added. After 9 minutes and 30 seconds after the completion of the silver nitrate aqueous solution addition, only the sodium behenate solution was added. It was made to be added. At this time, the temperature in the reaction vessel was set to 30 ° C., and the temperature was controlled so as not to rise. Further, the piping of the addition system of the sodium behenate solution was kept warm by steam tracing, and the amount of steam was controlled so that the liquid temperature at the outlet at the tip of the addition nozzle became 75 ° C. The piping of the silver nitrate aqueous solution addition system was kept warm by circulating cold water outside the double pipe. The addition position of the sodium behenate solution and the addition position of the aqueous silver nitrate solution were arranged symmetrically with respect to the stirring axis, and were adjusted to a height such that they did not come into contact with the reaction solution. After the completion of the addition of the sodium behenate solution, the mixture was left to stir at the same temperature for 20 minutes, and the temperature was lowered to 25 ° C. Then, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of the filtrate became 30 μS / cm. The solid thus obtained was stored as a wet cake without drying. The morphology of the obtained silver behenate particles was evaluated by electron microscopic photographing, and the average projected area diameter was 0.52 μm.
m, the average particle thickness was 0.14 μm, and the average spherical equivalent diameter was a scale-like crystal with a variation coefficient of 15%.

Next, a dispersion of silver behenate was prepared by the following method. For a wet cake having a dry solid content of 100 g, polyvinyl alcohol (Kuraray Co., Ltd., PV
A-217, average degree of polymerization: about 1700) and water were added to make a total amount of 385 g, and the mixture was predispersed with a homomixer. Next, the predispersed undiluted solution is dispersed in a dispersing machine (Microfluidizer M-110S manufactured by Microfluidics International Corporation).
-EH, using G10Z interaction chamber) at a pressure of 1750 kg / cm ² and treating three times,
A silver behenate dispersion A was obtained. In the cooling operation, a coiled heat exchanger was mounted before and after the interaction chamber, and the temperature of the refrigerant was adjusted to a desired dispersion temperature.
The silver behenate particles contained in the silver behenate dispersion A thus obtained had a volume-weighted average diameter of 0.52 μm and a coefficient of variation of 15%.
Particles. For particle size measurement, use MasterSizerX
(Malvern Instruments Ltd.). When evaluated by electron microscopy, the ratio of the long side to the short side was 1.
5, the grain thickness was 0.14 μm, and the average aspect ratio (the ratio of the circle equivalent diameter of the projected area of the grain to the grain thickness) was 5.1.

<< 1,1-bis (2-hydroxy-3,5)
-Dimethylphenyl) -3,5,5-trimethylhexane: Preparation of solid fine particle dispersion of reducing agent >> 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,
Surfynol 104E was added to 10 kg of 5,5-trimethylhexane and 10 kg of a 20% by mass aqueous solution of modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.).
400 g (manufactured by Nissin Chemical Co., Ltd.) and 640 methanol
g and 16 kg of water were added and mixed well to form a slurry. The slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2, manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes, and then benzoisothiazolinone sodium salt was added. 4 g and water were added to adjust the concentration of the reducing agent to 25% by mass to obtain a solid fine particle dispersion of the reducing agent. The reducing agent particles contained in the dispersion thus obtained had a median diameter of 0.44 μm, a maximum particle diameter of 2.0 μm or less, and a coefficient of variation of the average particle diameter of 19%. The resulting dispersion has a pore size of 3.
After filtration through a 0 μm polypropylene filter,
Foreign matter such as dust was removed and stored.

<< Preparation of Solid Fine Particle Dispersion of Organic Polyhalogen Compound-A >> Organic Polyhalogen Compound-A: 10 kg of tribromomethyl (4- (2,4,6-trimethylphenylsulfonyl) phenyl) sulfone and modified polyvinyl Alcohol (Poval MP20, manufactured by Kuraray Co., Ltd.)
10 kg of a 20% by mass aqueous solution of 3) and a 20% by mass aqueous solution of sodium triisopropylnaphthalenesulfonate 6
39g and Surfynol 104E (Nissin Chemical Co., Ltd.)
), 640 g of methanol and 16 kg of water, and mixed well to form a slurry. The slurry was sent by a diaphragm pump, dispersed in a horizontal sand mill (UVM-2, manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 5 hours, and water was added thereto to add an organic polyhalogen compound A. Was adjusted to be 25% by mass to obtain a solid fine particle dispersion of the organic polyhalogen compound-A. The organic polyhalogen compound particles contained in the dispersion thus obtained have a median diameter of 0.36 μm,
Maximum particle diameter 2.0 μm or less, variation coefficient of average particle diameter 18
%Met. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Solid Fine Particle Dispersion of Organic Polyhalogen Compound-B >> Organic polyhalogen compound B: 20 parts of 5 kg of tribromomethylnaphthyl sulfone and modified polyvinyl alcohol (Poval MP203, manufactured by Kuraray Co., Ltd.)
2.5 kg of a 20% by weight aqueous solution and 213 g of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate
And 10 kg of water were added and mixed well to form a slurry. This slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2, manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 5 hours, and then benzoisothiazolinone sodium salt was added. 5 g and water were added to adjust the concentration of the organic polyhalogen compound B to 23.5% by mass to obtain a solid fine particle dispersion of the organic polyhalogen compound B. The organic polyhalogen compound particles contained in the dispersion thus obtained had a median diameter of 0.38 μm, a maximum particle diameter of 2.0 μm or less, and a coefficient of variation of the average particle diameter of 20%. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Aqueous Solution of Organic Polyhalogen Compound-C >> Preparation formula (ratio per 100 ml of completed amount) and preparation procedure. Water 75.0 ml 20% aqueous solution of sodium tripropylnaphthalenesulfonate 8.6 ml 5% aqueous solution of sodium dihydrogen orthophosphate dihydrate 6.8 ml 1 mol / L aqueous solution of potassium hydroxide 9.5 ml organic polyhalogen compound- C (3-tribromomethanesulfonylbenzoylaminoacetic acid) 4.0 g The preparation procedure was performed as follows. 1. While stirring at room temperature, was added sequentially, and the mixture was stirred and mixed for 5 minutes after the addition. 2. Further, the powder was added while stirring, and was uniformly dissolved until the solution became transparent. 3. The obtained aqueous solution was filtered through a 200-mesh polyester screen to remove foreign substances such as dust, and stored.

<< Preparation of Emulsified Dispersion of Compound Z >> Compound Z
R-054 (manufactured by Sanko Co., Ltd.) containing 85% by mass of
After mixing 0 kg and 11.66 kg of MIBK, the mixture was replaced with nitrogen and dissolved at 80 ° C. for 1 hour. 25.52k of water
g and MP polymer (MP-203, manufactured by Kuraray Co., Ltd.)
12.76 kg of a 0% by weight aqueous solution and 0.4% of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate
Add 4 kg and add 6 kg at 20-40 ° C. and 3600 rpm.
Emulsified and dispersed for 0 minutes. Further, 0.08 kg of Surfynol 104E (manufactured by Nissin Chemical Co., Ltd.) and water 47.
After adding 94 kg and distilling under reduced pressure to remove MIBK, the concentration of compound Z was adjusted to be 10% by mass. The particles of compound Z contained in the dispersion thus obtained had a median diameter of 0.19 μm, a maximum particle diameter of 1.5 μm or less, and a coefficient of variation in particle diameter of 17%. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of 6-Isopropylphthalazine Compound Dispersion >> Preparation Formula (Ratio per 100 g of Complete Dispersion) and Preparation Procedure. Water 62.35 g Modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Poval MP203) 2.0 g Polyvinyl alcohol (manufactured by Kuraray Co., Ltd., PVA-217, 10% by mass aqueous solution) 25.5 g Sodium tripropylnaphthalenesulfonate (20 mass%) % Aqueous solution) 3.0 g 6-isopropylphthalazine (70% by mass aqueous solution) 7.15 g The dispersion was prepared by the following steps. 1. While stirring at room temperature, the mixture was added so as not to form a lump, and mixed by stirring for 10 minutes. 2. Thereafter, the mixture was heated and heated up to an internal temperature of 50 ° C., and then stirred for 90 minutes at an internal temperature of 50 to 60 ° C. to be uniformly dissolved. 3. The internal temperature is lowered to 40 ° C. or less, and is added,
The mixture was stirred for 30 minutes to obtain a transparent dispersion. 4. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Solid Fine Particle Dispersion of Nucleating Agent >> Table 1
1 kg of polyvinyl alcohol (Poval PVA-217, manufactured by Kuraray Co., Ltd.) for 4 kg of the nucleating agent described in
And 36 kg of water were added and mixed well to form a slurry. This slurry was sent by a diaphragm pump, and was fed to a horizontal sand mill (UVM-2, manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm.
After dispersion for a time, 4 g of benzoisothiazolinone sodium salt and water were added to adjust the nucleating agent concentration to 10% by mass to obtain a solid fine particle dispersion of the nucleating agent. The particles of the nucleating agent contained in the dispersion thus obtained had a median diameter of 0.3.
The particle size was 4 μm, the maximum particle size was 3.0 μm or less, and the variation coefficient of the particle size was 19%. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Solid Fine Particle Dispersion of Development Accelerator A >> 10 kg of development accelerator A, 10 kg of a 20% by mass aqueous solution of modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd., Poval MP203) and 20 kg of water were added. Mix well to form a slurry. This slurry was fed by a diaphragm pump and filled with zirconia beads having an average diameter of 0.5 mm in a horizontal sand mill (manufactured by Imex Co., Ltd., UV
After dispersing for 5 hours in M-2), water was added to adjust the concentration of the development accelerator A to 20% by mass to obtain a solid fine particle dispersion of the development accelerator A. The development accelerator particles contained in the dispersion thus obtained had a median diameter of 0.5 μm, a maximum particle diameter of 2.0 μm or less, and a coefficient of variation of the average particle diameter of 18%. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of Image Forming Layer Coating Solution >> The following binder, material, and silver halide emulsion A were added to 1 mol of silver of the silver behenate dispersion A prepared above.
Water was added to obtain an image forming layer coating solution. After completion, degassing under reduced pressure was performed at a pressure of 0.54 atm for 45 minutes. Coating liquid p
H was 7.7 and viscosity was 50 mPa · s at 25 ° C.

Binder; Luck Star 3307B (manufactured by Dainippon Ink and Chemicals, Incorporated, SBR latex, glass transition temperature 17 ° C.) 397 g as solid content 1-bis (2-hydroxy-3,5-dimethylphenyl) -3 5,5-trimethylhexane 149.5 g as solid content Organic polyhalogen compound B 36.3 g as solid content Organic polyhalogen compound C 2.34 g as solid content Sodium ethylthiosulfonate 0.47 g Benzotriazole 1.02 g Polyvinyl alcohol (Kuraray Co., Ltd., PVA-235) 10.8 g 6-isopropylphthalazine 15.0 g Compound Z 9.7 g as solid content Nucleating agent shown in Table 1 Amount shown in Table 1 Dye A (average molecular weight 15, (Added as a mixture with low molecular weight gelatin of 000) 783 nm light Coating amount at which the chemical concentration is 0.3 (solids 0.40 g as a guide) Silver halide emulsion A Ag amount 0.06 mol Compound A as a preservative 40 ppm in coating solution (2.5 mg / m2 coating amount) ² ) 1% by mass as the total solvent amount in the coating solution of methanol ² % by mass as the total solvent amount in the coating solution of ethanol (The glass transition temperature of the coating film was 17 ° C.)

[0119]

Embedded image

<< Preparation of Coating Solution for Protective Layer >> Methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2
-Hydroxyethyl methacrylate / acrylic acid = 5
8.9 / 8.6 / 25.4 / 5.1 / 2 (% by mass) of a polymer latex solution (copolymer having a glass transition temperature of 46
° C (calculated value), 21.5% by mass as a solid content, 100 ppm of compound A, and 15% by mass of a compound D as a film-forming aid with respect to the solid content of the latex. Was adjusted to 24 ° C., and water was added to 943 g of an average particle diameter of 116 nm to give Compound E at 1.62.
g, aqueous solution of organic polyhalogen compound-C 114.8
g, organic polyhalogen compound-A as solid content 17.
0 g, 0.69 g of sodium dihydrogen orthophosphate dihydrate as a solid content, and 1 g of the development accelerator A as a solid content.
1.55 g, matting agent (polystyrene particles, average particle size 7
μm, 1.58 g of average particle diameter variation coefficient 8%) and polyvinyl alcohol (PVA-235, manufactured by Kuraray Co., Ltd.)
29.3 g was added, and water was further added to prepare a coating solution (containing 0.8% by mass of a methanol solvent). After completion, deaeration under reduced pressure was performed at a pressure of 0.47 atm for 60 minutes. The coating solution had a pH of 5.5 and a viscosity of 45 mPa · s at 25 ° C.

<< Preparation of Coating Solution for Lower Overcoat Layer >> Methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2
(Mass%) of a polymer latex solution (copolymer, glass transition temperature: 46 ° C. (calculated value), solid content: 21.
5% by mass, 100 ppm of compound A, and compound D as a film-forming auxiliary in an amount of 1% based on the solid content of the latex.
5% by mass, the glass transition temperature of the coating solution was 24 ° C., and an average particle diameter of 74 nm) was added to 625 g of water. 2.7 g of compound H and 11.5 g of polyvinyl alcohol (PVA-235, manufactured by Kuraray Co., Ltd.)
Was added, and water was further added to prepare a coating solution (containing 0.1% by mass of a methanol solvent). After completion, deaeration under reduced pressure was performed at a pressure of 0.47 atm for 60 minutes. The coating solution had a pH of 2.6 and a viscosity of 30 mPa · s at 25 ° C.

<< Preparation of Coating Solution for Upper Overcoat Layer >> Methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2
(Mass%) of a polymer latex solution (copolymer, glass transition temperature: 46 ° C. (calculated value), solid content: 21.
5% by mass, 100 ppm of compound A, and compound D as a film-forming auxiliary in an amount of 1% based on the solid content of the latex.
Water was added to 649 g of 5% by mass and an average particle diameter of 116 nm (the glass transition temperature of the coating solution was set at 24 ° C.), and carnava wax (manufactured by Chukyo Yushi Co., Ltd., Cellosel 52)
4, silicone content less than 5 ppm) 30% by mass
18.4 g of solution, 0.23 g of compound C, 1.85 g of compound E, 1.0 g of compound G, matting agent (polystyrene particles, average particle diameter 7 μm, coefficient of variation of average particle diameter 8%)
3.45 g and polyvinyl alcohol (Kuraray Co., Ltd.)
Co., PVA-235) was added, and water was further added to prepare a coating solution (containing 1.1% by mass of a methanol solvent). After completion, vacuum degassing is performed at a pressure of 0.47 atm for 60
Minutes. The coating solution has a pH of 5.3 and a viscosity of 2 at 25 ° C.
It was 5 mPa · s.

[0123]

Embedded image

<< Preparation of Polyethylene Terephthalate (PET) Support with Back / Undercoat Layer >> (1) Preparation of PET Support Using terephthalic acid and ethylene glycol, the intrinsic viscosity IV = 0.66 (phenol / Tetrachloroethane = 6/4 (mass ratio) at 25 ° C.) to obtain polyethylene terephthalate. This was pelletized, dried at 130 ° C. for 4 hours, and then melted at 300 ° C.
After being extruded from the die, it is quenched and the film thickness after heat setting is 12
An unstretched film having a thickness of 0 μm was produced.
This is longitudinally stretched 3.3 times using rolls with different peripheral speeds.
Then, a transverse stretching was performed 4.5 times with a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After that, it was heat-set at 240 ° C. for 20 seconds, and relaxed 4% in the horizontal direction at the same temperature. Then, after slitting the chuck portion of the tenter, knurling is performed on both ends, and 4.8 k
g / cm ² . Thus, the width 2.4
m, length 3500 m, thickness 120 μm, roll-shaped PE
A T support was obtained.

(2) Preparation of Undercoat Layer and Back Layer Undercoat First Layer After subjecting the PET support to a corona discharge treatment at 0.375 kV · A · min / m ² , a coating solution having the following composition was applied to the PET support. .2 ml / m ² on a support,
C. for 30 seconds, 150.degree. C. for 30 seconds, and 185.degree. C. for 30 seconds.

Latex-A 280 g KOH 0.5 g Polystyrene fine particles (average particle diameter: 2 μm, coefficient of variation of average particle diameter 7%) 0.03 g 2,4-dichloro-6-hydroxy-s-triazine 1.8 g Compound Bc -C 0.097g Distilled water Amount that total amount becomes 1000g

Second layer of undercoat A coating solution having the composition shown below was applied on the first layer of undercoat so as to have a concentration of 5.5 ml / m ^2.
It dried at 30 degreeC for 30 second and 170 degreeC for 30 second.

Deionized gelatin (Ca ²⁺ content: 0.6 ppm, jelly strength: 230 g) 10 g Acetic acid (20% by mass aqueous solution) 10 g Compound-Bc-A 0.04 g Methyl cellulose (2% by mass aqueous solution) 25 g Polyethyleneoxy compound 3g Distilled water Amount that totals 1000g

Back first layer: 0.375 kV · V on the surface opposite to the undercoat layer application surface
A · min / m ² of corona discharge treatment is applied, and a coating solution having the following composition is applied to the surface so as to be 13.8 ml / m ^2, and is applied at 125 ° C. for 30 seconds, 150 ° C. for 30 seconds, 185 Dry at 30 ° C. for 30 seconds.

23 g of Julimer ET410 (30 mass% aqueous dispersion, manufactured by Nippon Pure Chemical Co., Ltd.) 23 g of alkali-treated gelatin (molecular weight: about 10,000, Ca ²⁺ content: 30 ppm) 4.44 g deionized gelatin (Ca ²⁺ content: 0.4%) 0.84 g Compound-Bc-A 0.02 g Dye-Bc-A (adjusted to an optical density of 1.33 to 1.4 at 783 nm) As a guide 0.88 g Polyoxyethylene phenyl ether 1.7 g Water-soluble melamine compound (Sumitomo Chemical Industries, Ltd., Sumitex Resin M-3, 8% by mass aqueous solution) 15 g FS-10D (Sb-doped SnO ₂ aqueous dispersion of needle-like particles, manufactured by Ishihara Sangyo Co., Ltd.) 24 g Polystyrene fine particles (average particle diameter 2 μm, coefficient of variation of average particle diameter 7%) 0.03 g Distilled water The amount that the total amount becomes 1000 g

Back second layer A coating solution having the composition shown below was applied on the first back layer so as to have a concentration of 5.5 ml / m ^2, and was applied at 125 ° C. for 30 seconds at 150 ° C.
For 30 seconds and 170 ° C. for 30 seconds.

Julimer ET410 (30% by mass aqueous dispersion, manufactured by Nippon Pure Chemical Co., Ltd.) 57.5 g Polyoxyethylene phenyl ether 1.7 g Water-soluble melamine compound (Sumitec Resin M-, manufactured by Sumitomo Chemical Co., Ltd.) 3,8% by mass aqueous solution) 15g Cellosol 524 (30% by mass aqueous solution, manufactured by Chukyo Yushi Co., Ltd.) 6.6g Distilled water Amount that gives a total amount of 1000g

Back Third Layer The same coating solution as that for the first undercoat layer was applied onto the second back layer at a concentration of 6.2 ml / m ^2, and then applied at 125 ° C. for 30 seconds for 150 seconds.
C. for 30 seconds and 185.degree. C. for 30 seconds.

Fourth Back Layer A coating solution having the composition shown below was applied on the third back layer so as to have a concentration of 13.8 ml / m ^2, and was applied at 125 ° C. for 30 seconds for 150 seconds.
It dried at 30 degreeC for 30 second and 170 degreeC for 30 second.

Latex-B 286 g Compound-Bc-B 2.7 g Compound-Bc-C 0.6 g Compound-Bc-D 0.5 g 2,4 dichloro-6-hydroxy-s-triazine 2.5 g Polymethyl methacrylate (10 Mass% aqueous dispersion, average particle diameter 5 μm, coefficient of variation of average particles 7%) 7.7 g distilled water Total amount of 1000 g

[0136]

Embedded image

(Latex-A) A core-shell type latex having a core portion of 90% by mass and a shell portion of 10% by mass. Core portion vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic acid = 93.
/3/3/0.9/0.1 (mass%) Shell part vinylidene chloride / methyl acrylate / methyl methacrylate / acrylonitrile / acrylic acid = 8
8/3/3/3/3 (% by mass) Weight average molecular weight 38000 (Latex-B) Methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate /
Acrylic acid = 59/9/26/5/1 (% by mass of copolymer)

(3) Heat treatment for transportation (3-1) Heat treatment PE thus prepared with a back / undercoat layer
The T support was placed in a heat treatment zone with a total length of 200 m set at 160 ° C., and transported at a tension of 2 kg / cm ² and a transport speed of 20 m / min. (3-2) Post-heat treatment After the heat treatment, post-heat treatment was performed by passing through a zone at 40 ° C for 15 seconds, and winding was performed. The winding tension at this time was 10 kg / cm ² .

<< Preparation of Photothermographic Material >> On the undercoat layer of the PET support on which the first undercoat layer and the second undercoat layer have been applied, FIG. 1 of JP-A-2000-2964 is disclosed. Using the slide beat coating method, the above-mentioned coating solution for the image forming layer was coated so as to have a coating silver amount of 1.5 g / m ² . Further, the coating solution for the protective layer was simultaneously and multi-layer coated with the coating solution for the image forming layer so that the solid content of the polymer latex was 1.29 g / m ² . Thereafter, the lower layer overcoat layer coating solution was coated on the protective layer with a solid content of polymer latex of 1.97 g / m ² and the upper overcoat layer coating solution was coated with a polymer latex solid content of 1.07 g / m ^2. m ² was applied simultaneously with the lower layer overcoat coating solution to form a photothermographic material. Drying at the time of application, the dew point is 14 to 25 ° C, and the liquid film surface temperature is 35 to 40 ° C in both the constant rate process and the deceleration process.
The drying was performed in a horizontal drying zone (at an angle of 1.5 ° to 3 ° with respect to the horizontal direction of the coating machine) up to the vicinity of the drying point at which the flow of the coating liquid almost disappeared. Also, the dry bulb temperature (T
1 to T6) and drying time were changed as shown in Table 1 and dried. Winding after drying is carried out under the conditions of a temperature of 23 ± 5 ° C. and a relative humidity of 45 ± 5%, and the winding form is adjusted to the subsequent processing form (image forming layer side outer winding), with the image forming layer side facing out. did. The humidity of the wrapping of the photosensitive material is 20 to relative humidity.
At 40% (measured at 25 ° C.), the film surface pH on the image forming side of the obtained photothermographic material was 5.0, the Beck smoothness was 850 seconds, and the film surface pH on the opposite side was 5.9. Smoothness is 5
60 seconds.

<< Evaluation of Actual Density >> The obtained photothermographic material was treated with a beam diameter (FWHM of ビ ー ム of the beam intensity) of 1
2.56 μm, laser output 50 mW, output wavelength 783
Using a single-channel cylindrical inner surface type laser exposure device equipped with a
Exposure was performed at 00 rpm for an exposure time of 1.2 × 10 ⁻⁸ seconds. The overlap coefficient at this time was 0.449, and the laser energy density on the photothermographic material surface was 7
5 μJ / cm ² . Using the laser exposure apparatus described above, test steps were output while changing the light amount at 175 lines / inch, and the following heat development processing was performed.
%, And the Dmax (maximum density) portion when the exposure was performed at an LV value of% was measured and defined as the actual density.

<< Evaluation of Development Humidity Dependence >> When a photothermographic material left to stand for 16 hours in an environment of 25 ° C. and a relative humidity of 80% is exposed to a line width of 60 μm under the above-mentioned conditions in the environment and subjected to heat development. And 1 in an environment of 25 ° C and 10% relative humidity.
When the photothermographic material left to stand for 6 hours was similarly exposed and heat-developed under the same environment, the line width and D
The min (fog) and Dmax (maximum density) were evaluated.
The density measurement was performed with a Macbeth TD904 densitometer (visible density). The line width fluctuation was calculated by the following equation. Line width variation =
Line width (25 ° C, relative humidity 80%)-line width (25 ° C, relative humidity 10%)

(Heat Developing Process) The exposed photothermographic material was subjected to a heat developing process using the heat developing machine shown in FIG. The roller surface material of the thermal development processing section is silicon rubber,
The smooth surface was made of Teflon nonwoven fabric, and the line speed of the conveyance was set at 150 cm / min. Preheating section 12.2
Seconds (The drive systems of the preheating unit and the heat development unit are independent, and the speed difference between the heat development unit and the heat development unit is set to -0.5% to -1%.
The temperature setting and time of the metal roller in each preheating section are as follows: the first roller temperature is 67 ° C, 2.0 seconds, the second roller temperature is 82 ° C,
2.0 seconds, third roller temperature 98 ° C, 2.0 seconds, fourth roller temperature 107 ° C, 2.0 seconds, fifth roller temperature 115 ° C, 2.0 seconds, sixth roller temperature 120 ° C, .
0 sec), a heat development process was performed at 120 ° C. (surface temperature of the photothermographic material) for 17.2 seconds, and a slow cooling unit was performed for 13.6 seconds. The temperature accuracy in the width direction was ± 0.5 ° C. The temperature of each roller was set to be 5 cm longer on both sides than the width of the photothermographic material (for example, 61 cm in width), and the temperature was applied to that portion so that the temperature accuracy was improved.
In addition, the temperature drop is sharp at both ends of each roller,
The part that is 5 cm longer than the width of the photothermographic material is set so that the temperature is 1-3 ° C. higher than the center of the roller,
Care was taken so that the image density of the photothermographic material (for example, within a width of 61 cm) was uniform. Table 1 shows the results of the above evaluations performed on each photothermographic material.

[0143]

[Table 1]

From the results shown in Table 1, it can be seen that the photothermographic material of the present invention shows a stable Dmax and Dm in both low and high humidity environments.
in, line width can be obtained.

<Example 2> Evaluation was carried out in the same manner as in Example 1 except that the preparation of the photosensitive material was as described below.
The same effect as in Example 1 was obtained. (Preparation of organic silver salt emulsion B) 840 g of behenic acid and 95 g of stearic acid were added to 12 liters of water, and while maintaining at 90 ° C., 48 g of sodium hydroxide and 63 g of sodium carbonate.
Was dissolved in 1.5 liters of water. 30
After stirring for 50 minutes, the temperature was raised to 50 ° C., 1.1 L of a 1% aqueous solution of N-bromosuccinimide (C-12) was added, and 2.3 L of a 17% aqueous solution of silver nitrate was gradually added with stirring. Further, the liquid temperature was set at 35 ° C., 1.5 liters of a 2% aqueous solution of potassium bromide was added over 2 minutes with stirring, and the mixture was stirred for 30 minutes, and 2.4 liters of a 1% aqueous solution of N-bromosuccinimide was added. To this aqueous mixture, 3300 g of a 1.2% by mass polyvinyl acetate butyl acetate solution was added with stirring, and the mixture was allowed to stand for 10 minutes to be separated into two layers, the aqueous layer was removed, and the remaining gel was washed twice with water. did. The gel-like mixture of behenic acid / silver stearate and silver bromide thus obtained was mixed with polyvinyl butyral (Denka Butyral # 3000, manufactured by Denki Kagaku Kogyo KK).
-K) in 1800 g of a 2.6% butanone solution,
Furthermore, polyvinyl butyral (manufactured by Denki Kagaku Kogyo Co., Ltd.
It was dispersed together with 600 g of denkabutyral # 4000-2) and 300 g of isopropyl alcohol to obtain an organic acid silver salt emulsion (needle-shaped particles having an average minor axis of 0.05 μm, an average major axis of 1.2 μm, and a variation coefficient of 25%).

(Preparation of Coating Solution for Emulsion Layer) Each chemical was added to the organic silver salt emulsion obtained above in the following amount per mole of silver. At 25 ° C., sodium phenylthiosulfonate 10 mg, sensitizing dye B 20 mg, sensitizing dye C 25 mg, sensitizing dye D 15 mg, 2-mercapto-5-methylbenzimidazole (C-1) 2 g, 2-mercapto 1 g of -5-methylbenzothiazole (C-2), 21.5 g of 4-chlorobenzophenone-2-carboxylic acid (C-3) and 2
-580 g of butanone and 220 g of dimethylformamide were added with stirring and left for 3 hours. Then,
Ditrichloromethyl-2-phenyltriazine (C-
4) 4.5 g, 2 g of disulfide compound A, 1,1-
Bis (2-hydroxy-3,5-dimethylphenyl)-
160 g of 3,5,5-trimethylhexane (C-5),
15 g of phthalazine (C-6), 5 g of tetrachlorophthalic acid (C-7), a nucleating agent used in Example 1, and a fluorinated surfactant (manufactured by Dainippon Ink and Chemicals, Megafax F-176P) ) 1.1 g, 2-butanone 590 g,
10 g of methyl isobutyl ketone were added with stirring.

(Preparation of Coating Solution for Emulsion Surface Protective Layer) Cellulose acetate butyrate (manufactured by Eastman Chemical Co., Ltd., CAB17)
1-15S) 75 g, 4-methylphthalic acid (C-8)
5.7 g, tetrachlorophthalic anhydride (C-9)
5 g, 10 g of 2-tribromomethylsulfonylbenzothiazole (C-10), 2 g of phthalazone (C-11), 0.3 g of Megafax F-176P, Sildex H
31 (manufactured by Dokai Chemical Co., Ltd., average spherical silica size: 3 μm)
5 g of polyisocyanate (sumidur N3500, manufactured by Sumitomo Bayer Urethane Co., Ltd.) in 2-butanone 3070
g and 30 g of ethyl acetate.

(Preparation of Support Having Back Surface) 6 g of polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo KK), Sildex H121 (manufactured by Dokai Chemical Co., Ltd., average spherical silica size: 12 μm) ) 0.2
g, Sildex H51 (manufactured by Dokai Chemical Co., Ltd., 0.2 g of true spherical silica) and 0.1 g of Megafax F-176P were added to 64 g of 2-propanol while stirring, and dissolved and mixed. Further, a mixed solution of 420 mg of Dye A dissolved in 10 g of methanol and 20 g of acetone and a solution of 0.8 g of 3-isocyanatomethyl-3,5,5, -trimethylhexyl isocyanate dissolved in 6 g of ethyl acetate were added thereto. Was prepared. The back surface coating solution was coated on a polyethylene terephthalate film having a moisture-proof undercoat containing vinylidene chloride on both sides at 633 nm.
Was applied so as to have an optical density of 0.7.

After the emulsion layer coating solution was coated on the support prepared as described above so that the silver content was 2 g / m ² , the emulsion surface protective layer coating solution was dried on the emulsion surface to a dry thickness of 5 μm. To obtain a sample of the heat-developable recording material. The structural formula of the compound used above is shown below. Further, some of them are used in Example 3, and the structural formulas of the compounds used only in Example 3 are also shown.

[0150]

Embedded image

[0151]

Embedded image

<Example 3> (Preparation of silver halide grains C) 7.5 g of inert gelatin and 10 mg of potassium bromide were dissolved in 900 ml of water, the pH was adjusted to 3.0 at a temperature of 35 ° C, and then silver nitrate was added. 74g
370 ml of an aqueous solution containing potassium bromide and potassium iodide in a molar ratio of 94: 6 and containing K ₃ [IrCl ₆ ] were added over 10 minutes by the control double jet method while maintaining the pAg at 7.7. . [IrCl6] ^3- was added in an amount of 3 × 10 ^-7 mol per mol of silver.
Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7-
0.3 g of tetrazaindene is added and the pH is adjusted to 5 with NaOH.
Adjusted to average size 0.06μm Projected area variation coefficient 8
%, And a {100} plane ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, desalted, and then 0.1 g of phenoxyethanol was added thereto.
9, adjusted to pAg 7.5.

(Preparation of Organic Acid Silver Emulsion C) Behenic acid
6 g and 300 ml of distilled water were mixed at 90 ° C. for 15 minutes, 31.1 ml of a 1 mol / L NaOH aqueous solution was added over 15 minutes with vigorous stirring, and the mixture was allowed to stand for 1 hour.
The temperature was lowered to ° C. Next, a 0.33 mol / L phosphoric acid aqueous solution 7m
After adding 0.13 g of N-bromosuccinimide (C-12) shown in the above formula (24) while stirring more vigorously, the silver halide grains B prepared in advance were adjusted to a silver halide amount of 2.5 m. It was added in molar amounts.
Further, 25 ml of a 1 mol / L silver nitrate aqueous solution was continuously added over 2 minutes, and stirring was continued for 90 minutes. 37 g of a 1.2% by mass solution of polyvinyl acetate in butyl acetate was added to the aqueous mixture to form flocs of the dispersion. The water was removed, followed by two additional water washes and water removal, followed by polyvinyl butyral. 20 g of a mixed solution of 2.5% by mass of butyl acetate and isopropyl alcohol (1: 2) of (Denka Butyral # 3000-K, manufactured by Denki Kagaku Kogyo Co., Ltd.) was added with stirring, and the thus obtained gelled organic material was obtained. To a mixture of acid and silver halide, polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo KK) 7.8
g and 2-butanone (57 g) were added and dispersed with a homogenizer to obtain a silver behenate emulsion (acicular particles having an average minor axis of 0.04 μm, an average major axis of 1 μm, and a variation coefficient of 30%).

(Preparation of Coating Solution for Emulsion Layer) Each chemical was added to the organic silver salt emulsion obtained above in the following amount per mole of silver. At 25 ° C., sodium phenylthiosulfonate 10 mg, sensitizing dye B 25 mg, sensitizing dye C 20 mg, sensitizing dye D 18 mg, 2-mercapto-5-methylbenzimidazole (C-1) 2 g, 4-chloro 21.5 g of benzophenone-2-carboxylic acid (C-3), 580 g of 2-butanone and 220 g of dimethylformamide were added with stirring, and the mixture was left for 3 hours. Then, 4 g of 4,6-ditrichloromethyl-2-phenyltriazine (C-4),
2 g of disulfide compound A, 170 g of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane (C-5), 5 g of tetrachlorophthalic acid (C-7), 15 g of phthalazine (C-6),
Nucleating agent and fluorinated surfactant used in Example 1 (Megafax F-176 manufactured by Dainippon Ink and Chemicals, Inc.)
P) 1.1 g, 2-butanone 590 g, and methyl isobutyl ketone 10 g were added with stirring.

(Preparation of Coating Solution for Emulsion Surface Protective Layer) Cellulose acetate butyrate (manufactured by Eastman Chemical Co., Ltd., CAB17)
1-15S) 75 g, 4-methylphthalic acid (C-8)
5.7 g, tetrachlorophthalic anhydride (C-9)
5 g, 5-tribromomethylsulfonyl-2-methylthiadiazole (C-13) 8 g, 2-tribromomethylsulfonylbenzothiazole (C-10) 6 g, phthalazine (C-11) 3 g, 0.3 g of Megafax F -1
A solution prepared by dissolving 2 g of 76P, Sildex H31 (manufactured by Dokai Chemical Co., Ltd., average spherical particle size 3 μm) and 6 g of polyisocyanate (sumidur N3500, manufactured by Sumitomo Bayer Urethane Co., Ltd.) in 3070 g of 2-butanone and 30 g of ethyl acetate was prepared. .

(Preparation of support having back surface) 6 g of polyvinyl butyral (Denka Butyral # 4000-2, manufactured by Denki Kagaku Kogyo KK), Sildex H121
(Tokai Chemical Co., Ltd., average spherical silica size 12μm)
0.2 g of Sildex H51 (manufactured by Dokai Chemical Co., Ltd., spherical silica average size 5 μm) and 0.1 g of Megafax F-176P were added to 64 g of 2-propanol while stirring, and dissolved and mixed. . In addition, 420
mg of dye A dissolved in 10 g of methanol and 20 g of acetone and 3-isocyanatomethyl-3,5,5
A coating solution prepared by dissolving 0.8 g of 5, -trimethylhexyl isocyanate in 6 g of ethyl acetate was added.

A coating solution for the back side was applied to a polyethylene terephthalate film having a moisture-proof undercoat containing vinylidene chloride on both sides so as to have an optical density of 688 nm of 0.7. The emulsion layer coating solution was coated on the support prepared as described above so that the silver content was 2 g / m ^2, and then the emulsion surface protective layer coating solution was coated on the emulsion surface to a dry thickness of 5 μm. Thus, a sample of the heat development recording material was obtained. When evaluated in the same manner as in Example 1, the photothermographic material of the present invention showed a stable Dmax and Dm both in a low humidity environment and in a high humidity environment as in Example 1.
in and line width could be obtained.

[0158]

According to the present invention, it has become possible to provide an image recording material having high sensitivity, small fog, stable against fluctuations in development processing conditions, and excellent image storage stability.

[Brief description of the drawings]

FIG. 1 is a side view showing a configuration example of a heat developing machine suitably used when the image recording material of the present invention is used as a heat-developable image recording material.

[Description of Signs] 10 Heat-developable image recording material 11 Carry-in roller pair 12 Carry-out roller pair 13 Roller 14 Smooth surface 15 Heater 16 Guide plate A Preheating unit B Heat development processing unit C Slow cooling unit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshihide Ezoe 210 Nakanakanuma, Minamiashigara, Kanagawa Prefecture Inside Fuji Photo Film Co., Ltd. (72) Inventor Tetsuo Yamaguchi 210 Nakanakanuma, Minamiashigara, Kanagawa Prefecture Fuji Photo Film Co. Reference) 2H123 AB00 AB02 AB22 AB28 BB00 BB27 CB00 CB03

Claims (1)

[Claims] 1. A support comprising at least (1) a photosensitive silver halide, (2) a reducible silver salt, (3) a reducing agent,
A heat-developable image recording material comprising (4) a binder and (5) at least one compound represented by the following formula (1). Embedded image [In the formula (1), X represents an alkoxy group, an aryloxy group, an amino group, or an alkylamino group;
Represents an alkyl group, an aryl group, or a heterocyclic group, and M represents a cation other than a hydrogen ion. ]