JP2003098629A - Material for recording thermally developed image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally developed image recording material that does not cause a planar defect such as a scratch and a failure such as jamming when an automatic transport system exposes and thermally develops the thermally developed image recording material. SOLUTION: In this thermally developed image recording material having at least one image formation layer on a base material and at least one protective layer provided over the image formation layer, the coefficient of dynamic friction between a surface having the image formation layer and the smooth surface of a stainless steel plate at 60 deg.C is <=0.7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable image recording material, and more particularly to a heat-developable photosensitive material for scanners and imagesetters suitable for photoengraving. When heat-developed, it can be smoothly and automatically transported without surface defects such as scratches, has a high Dmax (maximum density), has a high contrast (γ ≧ 10), and is ideal for photoengraving applications with low fog. It relates to a heat-developable image recording material for photoengraving capable of obtaining various images.

[0002]

2. Description of the Related Art Many image recording materials having a photosensitive layer on a support and forming an image by imagewise exposure are known. However, in the fields of medical treatment, printing plate making, etc., the waste liquid associated with the wet processing of the image recording material has been a problem in terms of workability, and in recent years, the reduction of the waste liquid treatment has been strong from the viewpoints of environmental protection and space saving. It has become desired. Therefore, attention is focused on the technology of the photothermographic image recording material for photoengraving, which can be exposed efficiently by a laser scanner or a laser imagesetter and can form a clear black image having high resolution and sharpness. Has been done. Since the heat-developable image recording material does not use a solution-type processing chemical, it is possible to provide a heat-development processing system which is simpler and does not damage the environment.

A method of forming an image by heat development is disclosed in, for example, US Pat. Nos. 3,152,904 and 3,45.
7,075, and D.I. Klostabour (Klos
terboer) “Silver System Heated (Thermal
ly Processed Silver Systems) A "(Imaging Processes and Materials)
ses and Materials) Neblette 8th edition, J. Sturge (S
turge), V. Walworth, A.A. Edited by Shepp, Chapter 9, p. 279, 1989)
It is described in. Such a heat-developable image recording material is
It contains a reducible non-photosensitive silver source (eg organic silver salt), a catalytically active amount of photocatalyst (eg silver halide), and a reducing agent of silver, usually dispersed in an organic binder matrix. The heat-developable image recording material is stable at room temperature, but is redox between a reducible silver source (which functions as an oxidizing agent) and a reducing agent when heated to a high temperature (eg, 80 ° C. or higher) after exposure. Silver is produced through the reaction. This redox reaction is promoted by the catalytic action of the latent image generated by exposure. The silver produced by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas and forms the image.

Although the above-mentioned heat-developable image recording materials have been conventionally known, most of them are image-forming layers formed by applying a coating solution using an organic solvent such as toluene, methyl ethyl ketone (MEK) or methanol as a solvent. Is formed. The use of an organic solvent as a solvent is not only harmful to the human body in the manufacturing process but also disadvantageous in terms of cost because the solvent is recovered.

Therefore, a method of forming an image forming layer by using a coating solution of such a water solvent which does not have such a worry has been considered. For example, JP-A-49-52626 and JP-A-53.
An example using gelatin as a binder is described in, for example, JP-A-116144. In addition, JP-A-50-15113
Japanese Patent No. 8 discloses an example in which polyvinyl alcohol is used as a binder.

Further, JP-A-60-61747 discloses an example in which gelatin and polyvinyl alcohol are used in combination. As another example, JP-A-58-28737
The publication describes an example of an image forming layer using a water-soluble polyvinyl acetal as a binder. Certainly, when such a binder is used, an image forming layer can be formed by using a coating solution of a water solvent, which has great advantages in terms of environment and cost.

However, when a polymer such as gelatin, polyvinyl alcohol or water-soluble polyacetal is used as a binder, dehydration shrinkage and thermal expansion of the binder occur at the same time during thermal development, which is different from the thermal expansion behavior of the support. In particular, in color printing, the registration accuracy deteriorates and color misregistration easily occurs.

Therefore, as a heat-developable image recording material for improving these drawbacks, JP-A-11-84573 proposes to use a polymer latex as a binder for an image forming layer and a protective layer and a back layer. However, when heat-development processing is performed using an automatic conveyance system device that automatically conveys the heat-development image recording material from the exposure device to the heat-development machine, the temperature of the members at the conveyance sites before and after the heat-development section (including preheating section) is The high temperature of 40 ° C. or higher often causes problems that the heat-developable image recording material causes scratches or jamming due to contact friction with the member.

A technique for improving the transportability of a heat-developable image recording material in an exposure / development processing system is disclosed in JP-A-10-4.
No. 8775 and Japanese Patent Laid-Open No. 2000-352788 disclose a technique for improving handling and transportability by setting the dynamic friction coefficient between the side having a photosensitive layer and the opposite side to 0.1 to 0.35, respectively. Described in JP 2000-2
No. 67225 discloses a technique for preventing an increase in Dmin due to contact friction when the coefficient of friction of the outermost layer is 0.4 or less. A technique for improving the continuous processing suitability of photosensitive materials of different sizes having a coefficient of dynamic friction with rubber of 0.5 or less is described.
Japanese Patent Laid-Open No. 023 and Japanese Patent Laid-Open No. 2001-2204 describe a technique for improving the transportability in a thermal developing machine by setting the dynamic friction coefficient of the back layer to 0.05 to 0.5. However, all of these techniques are techniques for lowering the coefficient of friction at a temperature of 30 ° C. or less to improve the transportability, and even if this technique is applied, the above-mentioned transportability problem should be completely solved. There was a strong demand for the development of improved technology.

[0010]

Therefore, the first problem to be solved by the present invention is to carry out exposure and heat development in an automatic transport system using an exposure apparatus such as a scanner and an image setter and a heat development apparatus. , Excellent in heat development processing without causing surface defects such as scratches and obstacles such as jamming, high Dmax (maximum density), and high contrast (γ ≧ 1
The object of the present invention is to provide a heat-developable image recording material for photoengraving capable of obtaining an image suitable for photoengraving which is 0) and has low fog. A second problem to be solved by the present invention is to provide a heat-developable image recording material which can be coated with water, which is advantageous in terms of environment and cost.

[0011]

As a result of intensive studies to solve the above problems, as a result, in an automatic transport system, the dynamic friction coefficient at a specific temperature between a specific member of an apparatus for exposure and thermal development and a thermal development image recording material is determined. It has been found that a heat-developable image recording material and an excellent image-forming method can be provided by solving the above problems by setting the content to a certain value or less, and the present invention has been completed. That is, according to the invention, at least 1
In a heat-developable image recording material having a two-layer image forming layer and at least one protective layer provided on the image forming layer, dynamic friction between the surface having the image forming layer and a smooth surface of a stainless steel plate at 60 ° C. Provided is a heat-developable image recording material having a coefficient of 0.7 or less.

The glass transition temperature of the outermost protective layer constituting the heat-developable image recording material of the present invention is preferably 40 ° C. or higher. Further, the coefficient of dynamic friction between the surface opposite to the side having the image forming layer and the smooth surface of the stainless steel plate at 60 ° C. is preferably 0.3 or less. Further, it is preferable to contain a lubricant and a matting agent in the outermost layer on the side having the image forming layer and / or the side opposite thereto. Further, it is preferable that a polymer latex is used as a binder for the protective layer, and the minimum film-forming temperature of the polymer latex is equal to or lower than the glass transition temperature of the protective layer. The heat-developable image recording material of the present invention has, on a support, an image forming layer containing an organic silver salt, a photosensitive silver halide and a reducing agent, and a back layer, and the support is heat-treated. Is preferred. Further, the heat-developable image recording material preferably contains a high contrast agent.

The present invention also includes an exposure device for exposing the heat-developable image recording material, a heat developing device equipped with a preheating part, a heat developing part, a slow cooling part and a deodorizing device, and an exposure device and a heat developing device. In conclusion, there is also provided an image forming method characterized in that an image of the above-mentioned heat-developable image recording material is formed by using an automatic carrying system device comprising an auto carrier for automatically carrying the heat-developable image recording material from the exposure device to the heat developing machine. provide.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-developable image recording material and image forming method of the present invention will be described in detail below. In addition,
In the present specification, "to" indicates a range including the numerical values described before and after it as the minimum value and the maximum value, respectively. The heat-developable image recording material of the present invention has at least one support on a support.
Layer, and at least one protective layer provided on top of the image forming layer. The present invention is characterized in that the coefficient of dynamic friction between the surface having the image forming layer and the smooth surface of the stainless steel plate at 60 ° C. is 0.7 or less. By having such characteristics, it is possible to obtain a heat-developable image recording material having excellent processability when forming a heat-developable image using an automatic transport system device.

The heat-developable image recording material of the present invention has at least one image forming layer, at least one protective layer on the upper side thereof, and at least one back layer on the opposite side thereof. Is preferred. The coefficient of dynamic friction between the surface having the image forming layer and the smooth surface of the stainless steel plate at 60 ° C. in the present invention is 0.7 or less, preferably 0.5 to
It is 0.05. Dynamic friction coefficient (μk) in the present invention
Can be measured and determined by the same principle as the friction coefficient test method described in JIS-K7125. Specifically, 2
After standing for 30 minutes or more under the condition of 5 ° C. relative humidity 55 ± 5%, the heat-developable image recording material was placed on the smooth surface (center line average roughness: Ra ≦ 0.05) of a stainless steel plate at 60 ° C.
A constant load (contact force: Ft, unit: g) is applied, the smooth surface of the stainless steel plate is slid at a constant speed, and the dynamic friction resistance force (Fk, unit: g) at that time is measured. ) Can be obtained from. Formula (1) μk = Fk / Ft

The coefficient of kinetic friction in the present invention can be appropriately controlled by incorporating a lubricant and a matting agent in the protective layer and using a polymer having a glass transition temperature of 40 ° C. or higher as the binder of the outermost protective layer. . The glass transition temperature of a polymer is, for example, “J. Brandrup, EHI
mmergut Co-authored Polymer Handbook, 2nd Edition, III-139 ~ II
I-192 (1975) ”.

Polymer latex is preferably used as the binder used in the protective layer of the heat-developable image recording material of the present invention. However, the "polymer latex" referred to herein is a polymer in which a water-insoluble hydrophobic polymer is dispersed as fine particles in a water-soluble dispersion medium. As the dispersed state, the polymer is emulsified in the dispersion medium, emulsion-polymerized, micelle-dispersed, or the polymer chain has a partially hydrophilic structure and the molecular chains themselves are molecularly dispersed. You can use any one. Regarding the polymer latex that can be used in the present invention, "Synthetic Resin Emulsion (Taira Okuda, edited by Hiroshi Inagaki, published by Kobunshi Kogyokai (1978))", "Application of synthetic latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki)" , Edited by Keiji Kasahara, published by Kobunshi Kogakukai (1993)), "Chemistry of Synthetic Latex (Souichi Muroi, published by Kobunshi Kogakukai (1970))" and the like. The average particle size of the dispersed particles is 1 to 500.
The range is preferably 00 nm, more preferably 5 to 1000 nm. The particle size distribution of the dispersed particles is not particularly limited, and may be a wide particle size distribution or a monodisperse particle size distribution.

The polymer latex used in the present invention may be a so-called core / shell type latex in addition to the usual polymer latex having a uniform structure. In this case, it may be preferable that the core and the shell have different glass transition temperatures (Tg). In particular, a core / shell type latex in which the Tg of the core is higher than the Tg of the shell provides good film-forming properties.

The glass transition temperature of the outermost protective layer is 40.
The temperature is preferably not lower than 0 ° C, more preferably 45 ° C to 70 ° C. The glass transition temperature of the protective layer is obtained by shaving the protective layer of the heat-developable image recording material by a layered cutting method,
JIS K7121 (Transition temperature measuring method), K712
It can be determined by differential scanning calorimetry (DSC) based on the test method of 2 (transition heat measurement method).

In the present invention, the minimum film forming temperature of the polymer latex of the protective layer is -30 ° C to 70 ° C, more preferably 0 ° C to 50 ° C. Furthermore, the minimum film formation temperature of the polymer latex is preferably not higher than the glass transition temperature of the polymer in the latex. A film forming aid may be added to control the minimum film forming temperature. The film-forming aid is also called a plasticizer and is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of the polymer latex. )"It is described in.

The following compounds may be mentioned as specific examples of the film-forming auxiliary. K-1 benzyl alcohol K-2 2-dimethylammonoethanol K-3 2,2,4-trimethylpentanediol-
1,3-monoisobutyrate K-4 diacetone alcohol K-5 ethylene glycol monobutyl ether K-6 dieterene glycol monobutyl ether acetate K-7 dibutyl phthalate K-8 diethylene glycol

Examples of the polymer species of the polymer latex used for the protective layer include acrylic resin, vinyl acetate resin, polyester resin, polyurethane resin, rubber resin, vinyl chloride resin, vinylidene chloride resin, polyolefin resin, and copolymers thereof. There is. 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 kinds of 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 5,000 to 1,200,000, preferably 1
About 10,000 to 1,000,000 is preferable. 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 formability is poor, which is not preferable.

The following may be mentioned as specific examples of the polymer latex used in the protective layer. Methyl methacrylate / ethyl acrylate / methacrylic acid copolymer latex, methyl methacrylate / butadiene / itaconic acid copolymer latex, ethyl acrylate / methacrylic acid copolymer latex, methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer latex, styrene / Butadiene / acrylic acid copolymer latex, styrene / butadiene / divinylbenzene / methacrylic acid copolymer latex, methylmethacrylate / 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 (mass%)
Copolymer latex of methyl methacrylate / butadiene / itaconic acid = 47.5 / 47.5 / 5 (mass%), copolymer latex of ethyl acrylate / methacrylic acid = 95/5 (mass%), and the like.

Further, such a polymer is commercially available, and the following polymers can be used. For example, as an example of acrylic resin, Sebian A-4635, 4658
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 (above Eastman Chemical) and other polyurethane resins HYDRAN AP10, 20,
LACSTAR 7310K, 330 as a rubber resin such as 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.)
7B, 4700H, 7132C (all manufactured by Dainippon Ink and Chemicals, Inc.), Nipol LX410, 430, 43
5,438C (all manufactured by Nippon Zeon Co., Ltd.), vinyl chloride resin such as G351, G576 (all manufactured by Nippon Zeon Corporation), vinylidene chloride resin L50, etc.
2, L513 (all manufactured by Asahi Kasei Corporation), Aron D7
020, D504, D5071 (Mitsui Toatsu Co., Ltd.)
Chemipearl S12 as an olefin resin
0, SA100 (all manufactured by Mitsui Petrochemical Co., Ltd.) and the like. These polymers may be used alone, or may be used by blending two or more kinds as necessary.

As the binder used in the protective layer, a polymer latex is most preferably used from the viewpoints of environment and dimensional stability, but it is transparent or translucent and generally colorless, and natural polymer synthetic resin or polymer and Copolymers, other film-forming media such as: gelatin, gum arabic, poly (vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinylpyrrolidone), casein, starch, poly (acrylic acid), poly (Methylmethacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal)
(Eg, poly (vinyl formal) and poly (vinyl butyral)), poly (ester) s, poly (urethane) s, phenoxy resin, poly (vinylidene chloride),
Hydrophilic or hydrophobic polymers such as poly (epoxides), poly (carbonates), poly (vinyl acetate) s, cellulose esters, poly (amides) can also be used.

In the present invention, the binder preferably used in the protective layer is a polymer having at least one monomer having a solubility in water at 25 ° C. of 0.1% by mass or more. It is a polymer having an I / O value of 0.55 to 1.0, preferably 0.55 to 0.8 obtained by dividing the inorganic value based on the organic value. If the I / O value is less than 0.55, the compound added to the outside of the film after the heat development treatment is liable to elute, and white powdery stains are likely to occur. Is likely to worsen.
When the protective layer is composed of two or more layers, the polymer I / O value of the protective layer adjacent to the image forming layer is 0.55.
Less than, preferably less than 0.55, 0.10 or more,
Further, at least one layer of I / O not adjacent to the image forming layer
The O value is preferably 0.55 or more and larger than the protective layer adjacent to the image forming layer.

The binder of the protective layer refers to the main binder, which is 60% by mass or more of the total binder. The total amount of binder in the protective layer is 0.2 to 10.0 g /
m ² , preferably in the range of 0.5 to 6.0 g / m ² .

The solubility of the monomer forming the polymer used for the protective layer in water at 25 ° C. is described in “4th Edition Experimental Chemistry Course 1 Basic Operation I” (1990, Maruzen Co., Ltd.).
It can be obtained by the method described in (Issue). Two
The solubility in water at 5 ° C. is 0.1% by mass or more, preferably 0.1% by mass to 10% by mass. Specific examples of the monomer include methyl acrylate, ethyl acrylate,
Examples include n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, methyl methacrylate, vinyl acetate, acrylonitrile, methacrylonitrile, acrylamide, acrylic acid, methacrylic acid, 2-hydroxyethyl methacrylate. .

I / O value of the polymer used for the protective layer,
That is, the value obtained by dividing the inorganic group based on the organic conceptual diagram by the organic group can be obtained by the method described in "Organic conceptual diagram-basic and applied-" (1984, Yoshio Koda, published by Sankyo Publishing Co., Ltd.). .

Here, the organic conceptual diagram means that the properties of the compound are divided into an organic group exhibiting a covalent bond property and an inorganic group exhibiting an ionic bond property, and all organic compounds are named as an organic axis and an inorganic axis. It is shown by locating each point on the orthogonal coordinates, and the inorganicity value based on this is inorganicity, that is, the influence of various substituents on the boiling point is determined based on the hydroxyl group, and the linear alcohol When the distance between the boiling point curve of 1 and the boiling point curve of linear paraffin is taken in the vicinity of 5 carbon atoms, it is about 100 ° C., so the influence of one hydroxyl group is set to 100 numerically. On the other hand, the organic value means that the size of the organic value can be measured by the number of carbon atoms representing the methylene group in the molecule, with the basic number of 1 carbon being The average value of the boiling point increase of 20 ° C. due to the addition of one carbon at around 5 to 10 carbon atoms of the straight chain compound was taken, and the value was set to 20 on the basis of this. The inorganic value and the organic value are determined so as to have a one-to-one correspondence on the graph. The I / O value is calculated from these values.

Specific examples of the compound of the preferable binder used in the protective layer having the image forming layer are shown below, but the invention is not limited to the following compounds.
The composition ratio is mass%, and the molecular weight is 80,000 to 1,000,000 in terms of weight average molecular weight. P-1 methyl methacrylate / methyl acrylate =
55/45 P-2 methyl methacrylate / methyl acrylate =
48/52 P-3 methyl methacrylate / methyl acrylate =
44/56 P-4 methyl methacrylate / methyl acrylate =
38/62 P-5 methyl acrylate / methyl methacrylate /
Styrene = 55/35/10 P-6 methyl acrylate / methyl methacrylate /
Styrene = 45/45/10 P-7 methyl methacrylate / ethyl acrylate =
70/30 P-8 methyl methacrylate / ethyl acrylate =
60/40 P-9 methyl methacrylate / n-butyl acrylate = 75/25 P-10 methyl methacrylate / n-butyl acrylate = 58/42 P-11 methyl acrylate / tert-butyl methacrylate = 60/40 P-12 methyl acrylate / Tert-butyl methacrylate / acrylic acid = 60/39/1 P-13 vinyl acetate / methyl methacrylate / acrylic acid = 80/20/1 P-14 methyl methacrylate / n-butyl acrylate / acrylonitrile = 70/25/5 P-15 methyl methacrylate / ethyl acrylate / acrylamide = 55/40/5 P-16 methyl methacrylate / ethyl acrylate / acrylic acid = 69/39/1 P-17 methyl acrylate / methyl methacrylate / Acrylic acid = 55/44/1 P-18 methyl methacrylate / n-butyl acrylate / acrylic acid = 74/25/1 P-19 Methyl acrylate / styrene / methyl methacrylate / acrylic acid = 73/15/11/1 P- 20 ethyl acrylate / methyl methacrylate / styrene / acrylic acid = 49/45/5/1 P-21 methyl methacrylate / styrene / n-butyl acrylate / acrylic acid = 60/32/5/3 P-22 methyl acrylate / methyl methacrylate / Hydroxyethyl methacrylate / acrylic acid = 54
/ 40/5/1

Polymer latex is preferably used as the binder of the image forming layer and the back layer on the side opposite to the side having the image forming layer. The glass transition temperature (Tg) of the polymer latex has different preferable ranges in the image forming layer and the back layer. In the image forming layer, the temperature is preferably -30 ° C to 40 ° C in order to promote diffusion of the photographic material during heat development. The temperature of the back layer is preferably 25 ° C to 150 ° C because it comes into contact with various devices.

As the polymer species used in the image forming layer and the back layer, a polymer selected from the binder species used in the protective layer can be used. Particularly preferred polymers are latex of styrene / butadiene / acrylic acid copolymer for the image forming layer, Julima-ET410 (manufactured by Nippon Pure Chemical Co., Ltd.), Chemipearl S120 (manufactured by Mitsui Petrochemical Co., Ltd.) for the back layer, Pethresin A520 (manufactured by Takamatsu Yushi Co., Ltd.) and the like.

The image forming layer comprises 50% by weight of all binders.
The polymer latex is preferably used in an amount of not less than 70% by mass, preferably not less than 70% by mass.

The total amount of binder in the image forming layer is 0.2 to 3
0 g / m ^2, preferably in the range of 1.0~15g / m ^2. The total amount of binder in the back layer is 0.01-10.
0 g / m ^2, preferably in the range of 0.05 to 5.0 g / m ^2.

Each of these layers may be provided in two or more layers. When the number of image forming layers is two or more, it is preferable to use polymer latex as a binder for all layers. The back layer is a layer provided above the undercoat layer on the back surface of the support, and there may be two or more layers, but it is preferable to use a polymer latex for at least one layer, particularly the outermost back layer.

In the present invention, each layer has a paragraph number 0023 to 00 in JP-A-2000-19678.
It can also be formed by using the first polymer latex having a functional group described in 41 and a crosslinking agent and / or a second polymer latex having a functional group capable of reacting with the first polymer latex. Specific examples of the functional group include a carboxyl group, a hydroxyl group, an isocyanate group, an epoxy group, an N-methylol group, an oxazolinyl group, an amino group, and a vinylsulfonyl group. Examples of the crosslinking agent include an epoxy compound, an isocyanate compound, and a blocked isocyanate compound. , Methyl compounds, hydroxy compounds, carboxyl compounds, amino compounds, ethyleneimine compounds, aldehyde compounds, halogen compounds and the like. Specific examples of the cross-linking agent include isocyanate compounds: hexamethylene isocyanate, Duranate WB40-80D, WX-1741 (manufactured by Asahi Kasei Co., Ltd.), Bayhijuru 3100 (manufactured by Sumitomo Bayer Urethane Co., Ltd.), Takenate WD725 (Takeda Pharmaceutical Co., Ltd. Co., Ltd.), Aquanate 100, 200 (manufactured by Nippon Polyurethane Co., Ltd.), water-dispersed polyisocyanate described in JP-A-9-160172, amino compound: Sumitex Resin M-3 (Sumitomo Chemical Co., Ltd.) Manufactured by Nagase Chemical Industry Co., Ltd., halogen compound: 2,4 dichloro-6-, epoxy compound: Denacol EX-614B
Hydroxy-1,3,5-triazine sodium and the like.

The slip agent added to the outermost layer of the surface having the image forming layer and / or the surface opposite thereto in the present invention is not particularly limited, and when it is present on the surface of an object, it is compared with the case where it is not present. Any compound that reduces the coefficient of friction on the surface may be used.

As the slipping agent used in the present invention, paragraph Nos. 0061 to 006 of JP-A No. 11-84573 can be used.
4. Paragraph number 00 of Japanese Patent Application No. 2000-47083
49 to 0062. Specific examples of preferable slip agents include Cerosol 524 (main component carnauba wax), polysiloxane, polylon A, 393 and H.
-481 (main component polyethylene wax), High Micron G-110 (main component ethylenebisstearic acid amide), High Micron G-270 (main component stearic acid amide) (above, manufactured by Chukyo Yushi Co., Ltd.), W-1 _{C 16 H 33 -O-SO 3} Na, W-2 C 18 H 37 -O-SO 3 Na W-3 C 17 H 33 CONH (CH 3) , and the like CH ₂ CH ₂ SO ₃ Na. The amount of the slipping agent used is 0.1 to 50% by mass, preferably 0.5 to 30% by mass, based on the amount of the binder in the additive layer.

In the present invention, Japanese Patent Laid-Open No. 2000-1719.
No. 35, JP-A-2001-22024, the preheating unit is conveyed by a counter roller, and the heat development processing unit drives the roller to drive the side having the image forming layer so that the back surface on the opposite side is moved. When using a heat development processing apparatus that slides and conveys on a smooth surface, the ratio of the friction coefficient between the outermost surface layer on the side having the image forming layer of the heat development image recording material and the outermost surface layer of the back surface at the development processing temperature is , 1.5 or more,
The upper limit is not particularly limited, but is about 30. Also,
It is preferable that μb is 1.0 or less, preferably 0.8 to 0.05. This value is calculated by the following formula. Friction coefficient ratio = coefficient of dynamic friction between roller member of heat developing machine and surface having image forming layer (μe) / coefficient of dynamic friction between smooth surface member of heat developing machine and back surface (μb)

The matting agent contained in the outermost layer of the surface having the image forming layer and / or the surface opposite thereto in the present invention is disclosed in paragraph No. 005 of JP-A No. 11-84573.
Those described in 2 to 0059 can be used. The Beck smoothness of at least one of the surface having the image forming layer of the heat-developable image recording material of the present invention and the surface opposite to the surface, preferably both, is 5000 seconds or less, more preferably 100 seconds to 4000 seconds. Is. The Beck's smoothness can be controlled by appropriately changing the particle size & content of the matting agent. Beck's smoothness in the present invention is based on Japanese Industrial Standard (JIS) P8119.
"Smoothness test method for paper and board by Beck tester"
And TAPPI standard method T479.

Regarding the hardness of the coating film on the surface having the image forming layer and / or the surface on the opposite side in the present invention, the Vickers hardness at 40 ° C. is preferably 30 N / mm ² or more, and 40 to 300 N / mm. More preferably, it is mm ² . In particular, the Vickers hardness of the surface having the image forming layer preferably has these values. The Vickers hardness can be determined by the Vickers hardness test method described in JIS Z2244, B7725. Specifically, using a diamond regular pyramid indenter with a facing angle of 136 degrees,
It is determined by the following formula (2) from the test force F (N) when the test surface is dented and the surface area (mm ² ) of the dent. Formula (2) HV = 0.1891 F / d ² Formula WHEREIN: HV: Vickers hardness, F: Test force (N), d:
Average of Diagonal Lengths in Two Directions of Dimples (mm) In the present invention, H100V manufactured by Fisher Scope
Using P, sample temperature 40 ℃, test force: 300mm
N, indentation depth: hardness at 2 μm was measured.

The image forming layer coating solution or the protective layer coating solution in the present invention is preferably a so-called pseudoplastic fluid. Pseudoplasticity refers to the property that the viscosity decreases as the shear rate increases.

The coating liquid for the image forming layer in the present invention has a shear rate of 0.1 s ^{-1 and} 100 mPa · s or more,
It is preferably 100 mPa · s to 10000 mPa · s, and more preferably 200 mPa · s to 5000 m.
Pa · s. And 1 at a shear rate of 1000 s ^-1
The mPa · s to 100 mPa · s is preferable. The coating solution for protective layer in the present invention is 10 at a shear rate of 0.1 s ^-1 .
mPa · s or more and 5000 mPa · s, and preferably 20 mPa · s to 3000 mPa · s.

The viscosity and shear rate in the present invention are defined as follows. Consider a model fluid that exists between two parallel planes. One of these two planes is fixed and the other one is movable, and the distance between them is x. Moving surface (top surface)
If force F acts on and the upper surface slides with respect to the lower surface at velocity v, the fluid layer between the two planes will also have the same lateral displacement.
The top fluid moves the fastest and the bottom fluid moves the slowest. The middle layer moves at the intermediate speed. However, the velocity gradient dv / dx is the same for any part of the fluid. This velocity gradient γ is defined as the shear rate in the present invention. The total force acting on the top surface (area A) is F and its stress is F / A. When this force is defined as shear stress τ, the viscosity η in the present invention is defined by the ratio τ / γ of shear stress and shear rate.

Although any device may be used for the viscosity measurement in the present invention, an RFS fluid spectrometer manufactured by Rheometrics Far East Co., Ltd. is preferably used, and the viscosity is measured at 25 ° C.

In the present invention, a water-soluble polymer is preferably used as a viscosity modifier for imparting coatability to each layer, and it is not limited to a natural product or a synthetic polymer. As natural products, they are starches (corn starch, starch, etc.), seaweed (agar, sodium alginate, carrageenan, etc.), vegetable sticky substances (gum arabic, etc.), animal proteins (such as glue, casein, gelatin, egg white, etc.). , Fermented sticky substances (pullulan, dextrin, etc.) and semi-synthetic polymers such as starches (soluble starch, carboxyl starch, dextran, etc.), celluloses (viscose, methylcellulose, ethylcellulose, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropyl) Cellulose, hydroxypropylmethyl cellulose, etc.), synthetic polymers (polyvinyl alcohol, polyacrylamide, polyvinyl pyrrolidone, polyethylene glycol, poly Ropylene glycol, polyvinyl ether, polyethyleneimine, polystyrenesulfonic acid or its copolymer, polyvinylsulfinic acid or its copolymer, polyacrylic acid or its copolymer, acrylic acid or its copolymer, maleic acid copolymer , Maleic acid monoester copolymer, acryloylmethyl propane sulfonic acid or its copolymer, and the like). These compounds are “Applications and markets of new water-soluble polymers (published by CMC,
"Edited by Shinji Nagatomo, published November 4, 1988)".

Among these, water-soluble polymers preferably used are gelatin, polyvinyl alcohol (for example, PVA-205, PVA-217 manufactured by Kuraray Co., Ltd.,
PVA-224, PVA-235), κ-carrageenan, xanthan gum, locust bean gum, methyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, polycarboxylic acid, polystyrene sulfonic acid, modified polyacrylic sulfonic acid (for example, SAN. NOPCO
LIMITED SN thickener A-818), modified polyacrylic carboxylic acid (for example, SAN NOPCO
Examples include SN thickener A-815 manufactured by LIMITED, poly N-vinylacetamide (BIAC GE-191, GE-167 manufactured by Showa Denko KK), and the like.

The amount of the water-soluble polymer used as the viscosity modifier is not particularly limited as long as the viscosity increases when added to the coating solution. Generally, the concentration in the liquid is 0.01 to 30% by mass.
And more preferably 0.05 to 20 mass%,
It is particularly preferably 0.1 to 10% by mass. The viscosity obtained by these is the value measured by a B-type rotational viscometer (N
o. The viscosity of the coating solution of the image forming layer at 25 ° C. is preferably 15 to 100 mPa · s, and more preferably 30 to 70 mPa · s. On the other hand, the viscosity of the coating liquid of the protective layer is 5 to 75 mPa · s at 25 ° C.
Is preferable, and more preferably 20 to 50 mPa · s. In addition to the coating solution and the like, it is generally desirable to add the viscosity modifier as dilute solution as possible.
In addition, it is preferable to perform sufficient stirring during the addition.

The organic silver salt that can be used in the present invention is
It is relatively stable to light, but forms a silver image when heated to 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. The organic silver salt may be any organic substance containing a source capable of reducing silver ions. Silver salt of organic acid,
In particular (having 10 to 30 carbon atoms, preferably 15 to 28 carbon atoms)
Silver salts of long-chain fatty carboxylic acids are preferred. Ligands 4.0
Complexes of organic or inorganic silver salts having complex stability constants in the range of -10.0 are also preferred. The silver-providing substance can preferably constitute about 5 to 70% by mass of the image forming layer. Preferred organic silver salts include silver salts of organic compounds having a carboxyl group. Examples of these include, but are not limited to, silver salts of aliphatic carboxylic acids and silver salts of aromatic carboxylic acids. Preferred examples of the silver salt of an aliphatic carboxylic acid include silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver caproate,
It includes silver myristate, silver palmitate, silver maleate, silver fumarate, silver tartrate, silver linoleate, silver butyrate and silver camphorate, mixtures thereof and the like.

In the present invention, it is preferable to use the organic acid silver having a silver behenate content of 75 mol% or more, and more preferably 85 mol% or more, among the organic acid silver or the mixture of the organic acid silver mentioned above. Here, the silver behenate content 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 listed above can be preferably used.

The organic acid silver salt preferably used in the present invention is
Alkali metal salts of the organic acids shown above (Na salt, K salt,
It is prepared by reacting silver nitrate with a solution or suspension (such as Li salt). For the preparation method thereof, see paragraph No. 00 of JP-A No. 2000-292882.
The methods described in 19 to 0021 can be used.

In the present invention, a method of preparing an organic acid silver salt can be preferably used by adding an aqueous silver nitrate solution and an organic acid alkali metal salt solution into a means for mixing a sealed liquid. As a method for preparing these, the method described in JP 2001-33907 A can be used.

In the present invention, when the organic silver salt is prepared, a water-soluble dispersant can be added to the silver nitrate aqueous solution and the organic acid alkali metal salt solution or the reaction solution used. Specific examples of the type and amount of the dispersant used are described in JP-A 2000-305214, paragraph No. 00.
52.

The organic silver salt used in the present invention is preferably prepared in the presence of a tertiary alcohol. The tertiary alcohol preferably has a total carbon number of 15 or less,
Particularly preferred is 10 or less. Examples of preferable tertiary alcohols include tert-butanol and the like, but the present invention is not limited thereto.

The tertiary alcohol used in the present invention may be added at any time during the preparation of the organic acid silver salt, but it may be added during the preparation of the organic acid alkali metal salt and used by dissolving the organic acid alkali metal salt. It is preferable. Further, the amount of the tertiary alcohol used can be arbitrarily used within a range of 0.01 to 10 by mass ratio with respect to water as a solvent at the time of preparing the organic silver salt, but within a range of 0.03 to 1. preferable.

The shape and size of the organic silver salt that can be used in the present invention are not particularly limited.
The thing described in paragraph number 0024 of the 882 publication can be used. The shape of the organic silver salt can be measured by a transmission electron microscope image of the organic silver salt dispersion. As another method of measuring the monodispersity, there is a method of obtaining the standard deviation of the volume weighted average diameter of the organic silver salt, and the percentage (variation coefficient) of the value divided by the volume weighted average diameter is preferably 80% or less, It is preferably 50% or less, more preferably 30% or less. As a measuring method, for example, the particle size (volume-weighted average diameter) obtained by irradiating an organic silver salt dispersed in a liquid with laser light and obtaining an autocorrelation function with respect to the time change of the fluctuation of scattered light You can A solid fine particle dispersion having an average particle size of 0.05 μm to 10.0 μm in this measuring method is preferable. More preferably, the average particle size is 0.1 μm
5.0 μm, more preferably 0.1 μm average particle size
It is m-2.0 micrometers.

The organic silver salt that can be used in the present invention is
Preferably desalting can be carried out. The desalting method is not particularly limited, and a known method can be used, but a known filtration method such as centrifugal filtration, suction filtration, ultrafiltration, or floc-forming water washing by a coagulation method can be preferably used. For the ultrafiltration method, see Japanese Patent Application Laid-Open No. 2000-
The method described in Japanese Patent No. 305214 can be used.

In the present invention, for the purpose of obtaining an organic silver salt solid dispersion having a high S / N, a small particle size and no aggregation, an organic silver salt as an image forming medium is contained and a photosensitive silver salt is substantially contained. It is preferable to use a dispersion method in which an aqueous dispersion liquid that does not contain water is converted into a high-speed flow and then the pressure is lowered. As the dispersing method, the method described in paragraph Nos. 0027 to 0038 of JP-A-2000-292882 can be used.

The particle size (volume-weighted average diameter) of the organic silver salt solid fine particle dispersion is determined by, for example, irradiating the solid fine particle dispersion dispersed in a liquid with a laser beam, and the autocorrelation function with respect to the time change of the fluctuation of the scattered light. Can be determined from the particle size (volume-weighted average diameter) and transmission electron microscope image obtained by determining Average particle size 0.0
A solid fine particle dispersion of 5 μm to 10.0 μm is preferable.
More preferably, the average particle size is 0.1 μm to 5.0 μm.
m, more preferably an average particle size of 0.1 μm to 2.
It is 0 μm.

The particle size distribution of the organic silver salt solid fine particle dispersion is preferably monodisperse. Specifically, the percentage (variation coefficient) of the value obtained by dividing the standard deviation of the volume-loaded average diameter by the volume-loaded average diameter is 80% or less, more preferably 50.
% Or less, more preferably 30% or less.

The organic silver salt solid fine particle dispersion used in the present invention comprises at least an organic silver salt and water. The ratio of the organic silver salt and water is not particularly limited, but the ratio of the organic silver salt in 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 dispersion aid, but it is preferable to use the minimum amount within a range suitable for minimizing the grain size, and 0.5 to 30% by mass, particularly 1 to 30% by mass based on the organic silver salt.
The range of 15 mass% is preferable.

In the present invention, the organic silver salt can be used in a desired amount.
However, the silver amount is 0.1-5 g / m ²Is preferred and
Preferably 1 to 3 g / m²Is.

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 the metal ion selected from Ca, Mg, Zn and Ag to the non-photosensitive organic silver salt,
It is preferable to add it in the form of a water-soluble metal salt that is not a halide, and more specifically, it is preferable to add it in the form of nitrate or sulfate. Addition with a halide deteriorates the image storability due to light (indoor light, sunlight, etc.) of the heat-developable image recording material, especially the heat-developable light-sensitive material after processing, which is not preferable. Therefore, in the present invention, it is preferable to add in the form of a water-soluble metal salt that is not a halide.

Ca, Mg, Zn preferably used in the present invention
The metal ion selected from Ag and Ag may be added at any time after particle formation of the non-photosensitive organic silver salt, immediately after particle formation, before dispersion, after dispersion and before and after coating such as before and after preparation of coating solution. Well, preferably after dispersion and before and after preparation of the coating solution.

Ca, Mg, Zn and A in the present invention
The addition amount of the metal ion selected from g is preferably 10 ⁻³ to 10 ⁻¹ mol, and particularly preferably 5 × 10 ^{−3 to} 5 × 10 ⁻² mol per mol of the non-photosensitive organic silver.

The photosensitive silver halide used in the present invention is not particularly limited in halogen composition, and silver chloride, silver chlorobromide, silver bromide, silver iodobromide, silver iodochlorobromide can be used. .. Regarding the grain formation of the photosensitive silver halide emulsion, paragraph 021 of JP-A No. 11-119374 is referred to.
Particles can be formed by the method described in No. 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-shaped, and potato-shaped grains, but in the present invention, cubic grains or tabular grains are particularly preferable. Regarding the characteristics of the particle shape such as the aspect ratio and surface index of the particles, Japanese Patent Application Laid-Open No. 11-119.
It is the same as that described in paragraph No. 0225 of Japanese Patent No. 374. The distribution of the halogen composition may be uniform inside and on the surface of the silver halide grain, the halogen composition may be changed stepwise, or may be continuously changed. 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-fold structure, more preferably a 2- to 4-fold structure, can be used. Further, a technique of localizing silver bromide on the surface of silver chloride or silver chlorobromide grains can also be preferably used.

The grain size distribution of the silver halide grains used in the present invention has a monodispersity value of 30% or less, preferably 1.
-20% or less, and further 5-15%. Here, the monodispersity is defined as the percentage (%) (variation coefficient) of the value obtained by dividing the standard deviation of the particle diameter by the average particle diameter.
For the sake of convenience, the grain size of silver halide grains is represented by the edge length in the case of cubic grains, and other grains (octahedral, tetradecahedral,
Flat plate shape) is calculated by the diameter equivalent to the projected area circle.

The photosensitive silver halide grains contain a metal or metal complex of Group VII or VIII of the periodic table. The metal of Group VII or VIII of the Periodic Table or the central metal of the metal complex is preferably rhodium, rhenium, ruthenium, osmium or iridium. A particularly preferred metal complex is (NH ₄ ) ₃ Rh (H
₂ O) Cl ₅ , K ₂ Ru (NO) Cl ₅ , K ₃ IrCl ₆ , K
₄ is a Fe (CN) _6. One of these metal complexes may be used, or two or more of the same metal complex and different metal complexes may be used in combination. The preferred content is 1 × 10 with respect to 1 mol of silver.
^{The range of -9} mol to 1 × 10 ^-3 mol is preferable, and 1 ×
The range of 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol is more preferable. As a specific structure of the metal complex, JP-A-7-225
A metal complex having a structure described in Japanese Patent No. 449, etc. can be used. Regarding the types and addition methods of these heavy metals, paragraph No. 022 of JP-A No. 11-119374.
7-0240.

The photosensitive silver halide grains can be desalted by washing with water by a method known in the art such as a noodle method and a flocculation method, but in the present invention, it may or may not be desalted. . The photosensitive silver halide emulsion is preferably chemically sensitized. Regarding the chemical sensitization, paragraph numbers 0242 to 025 of JP-A No. 11-119374 are disclosed.
The method described in No. 0 is used. To the silver halide emulsion, a thiosulfonic acid compound may be added according to the method shown in EP 293,917.

The gelatin contained in the photosensitive silver halide used in the present invention is in order to maintain a good dispersion state of the photosensitive silver halide emulsion in an organic silver salt-containing coating solution.
It is preferred to use low molecular weight gelatin. The low molecular weight gelatin has a molecular weight of 500 to 60,000, and preferably a molecular weight of 1,000 to 40,000. These low molecular weight gelatins may be used during grain formation or dispersion after desalting treatment, but are preferably used during dispersion after desalting treatment. Ordinary gelatin (molecular weight of about 100,000) may be used at the time of grain formation, and low molecular weight gelatin may be used at the time of dispersion after desalting treatment.

The concentration of the dispersion medium may be 0.05 to 20% by mass, but a concentration range of 5 to 15% by mass is preferable in terms of handling. Alkali-treated gelatin is usually used as the type of gelatin, but other acid-treated gelatin,
Modified gelatin such as phthalated gelatin can also be used.

The silver halide emulsion in the heat-developable image recording material used in the present invention may be of one kind or two or more kinds (for example, those having different average grain sizes, those having different halogen compositions, and those having crystal habits). Different ones, different chemical sensitization conditions) may be used together.

The amount of photosensitive silver halide used is 0.01 mol of photosensitive silver halide per mol of organic silver salt.
1 to 0.5 mol is preferable, 0.02 mol to 0.3
mol is more preferable, 0.03 mol to 0.25 mo
l is particularly preferred. Regarding the mixing method and mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide grains and organic silver salt are mixed with a high-speed stirrer, a ball mill, a sand mill, a colloid mill, a vibration mill, a homogenizer. And the like, or a method of preparing an organic silver salt by mixing the photosensitive silver halide prepared at any timing during the preparation of the organic silver salt, but the effect of the present invention is sufficient. There is no particular limitation as long as it appears in. Further, mixing two or more organic silver salt aqueous dispersions and two or more photosensitive silver salt aqueous dispersions at the time of mixing is a method preferably used for controlling photographic characteristics.

The sensitizing dye applicable to the present invention is capable of spectrally sensitizing silver halide grains in a desired wavelength region when adsorbed on silver halide grains, and has a spectral sensitivity suitable for spectral characteristics of an exposure light source. The sensitizing dye having can be advantageously selected. For example, as a dye that spectrally sensitizes a wavelength region of 550 nm to 750 nm, there is disclosed in Japanese Patent Laid-Open No. 10-1865.
The dyes represented by the general formula (II) in JP-A-72 are mentioned, and specifically, II-6, II-7, II-14, II.
These are dyes of -15, II-18, II-23, and II-25. Examples of the dye that spectrally sensitizes the wavelength region of 750 to 1400 nm include dyes represented by the general formula (I) in JP-A No. 11-119374, and specifically, (25) and (26). , (30), (32), (36),
(37), (41), (49) and (54) dyes. Further, as a dye forming J-band, US Pat. No. 5,510,236, U.S. Pat. No. 3,871,8
Dye described in Example 5 of Japanese Patent No. 87, JP-A-2-96
Examples of the dyes include those disclosed in JP-A No. 131 and JP-A No. 59-48753. These sensitizing dyes may be used alone or in combination of two or more.

The sensitizing dye may be added by the method described in paragraph No. 0106 of JP-A No. 11-119374, but the method is not particularly limited to this method. The addition amount of the sensitizing dye in the present invention may be a desired amount depending on the sensitivity and fog performance, but it is 1 per 1 mol of silver halide in the photosensitive layer.
0 ^{-6 to 1} mol is preferable, more preferably 10 ^-4 to
It is 10 ^-1 mol.

In order to improve the spectral sensitization efficiency of the present invention,
A supersensitizer can be used. The supersensitizer used in the present invention is described in EP 587,338, US Pat. No. 3,877,943, and EP 4,87.
Examples thereof include compounds disclosed in Japanese Patent No. 3,184, heteroaromatic or aliphatic mercapto compounds, heteroaromatic disulfide compounds, compounds selected from stilbene, hydrazine and triazine. Particularly preferred supersensitizers are heteroaromatic mercapto compounds and heteroaromatic disulfide compounds disclosed in JP-A-5-341432, and general formula (I) or (II) of JP-A-4-182639. A compound represented by:
A stilbene compound represented by the general formula (I) in JP-A-111543 and a compound represented by the general formula (I) in JP-A No. 11-109547. Specifically, JP-A-5
Compounds M-1 to M-24 in JP-A-341432, compounds d-1) to d-14) in JP-A-4-182639, and SS-01 in JP-A-10-111543.
To SS-07 compounds, 31, 32, 37, 38, 41-45, 51-53 of JP-A-11-109547.
Is a compound of.

The addition amount of these supersensitizers is preferably in the range of 10 ^{−4 to} 1 mol per mol of silver halide in the emulsion layer, and more preferably 1 m of silver halide.
The amount is 0.001 to 0.3 mol per ol.

Next, the contrast increasing agent that can be used in the present invention will be described. The type of contrast enhancing agent used in the present invention is not particularly limited, but as a well-known contrast enhancing agent,
A hydrazine derivative represented by the formula (H) described in JP-A-2000-284399 (specifically, Tables 1 to 1 of the publication).
(Hydrazine derivatives described in Table 4), JP-A-10-106
72, JP-A-10-161270, JP-A-10-62898, JP-A-9-304870, JP-A-9-304872, and JP-A-9-304.
871, JP-A-10-31282, US Pat. No. 5,496,695, European Patent Publication EP7.
All of the hydrazine derivatives described in JP 41,320A can be mentioned. In addition, Japanese Patent Laid-Open No. 2000-284
A substituted alkene derivative, a substituted isoxazole derivative and a specific acetal compound represented by the formulas (1) to (3) described in JP-A No. 399, and furthermore, the formula (A) or the formula (B) described in the same publication. A cyclic compound represented by the formula, specifically, Compounds 1 to 72 described in Chemical formulas 8 to 12 of the publication. Compounds represented by the general formulas (H), (G) and (P) described in JP 2001-133924 A, specifically, [Chemical formula 3] to [Chemical formula 9] and [Chemical formula 11] of the same document. ~ [Chemical 53]
Can be mentioned. A plurality of these contrast adjusting agents may be used in combination.

The contrast increasing agent particularly preferably used in the present invention is represented by the general formulas (H-1), (H-2), (H-3) and (H-4) described in JP-A 2001-27790. ,
Hydrazine derivatives represented by (H-5) and (H-1-1) (specifically, compounds H-1-1 to H- described in the publication).
1-28, Compounds H-2-1 to H-2-9, Compound H-
3-1 to H-3-12, Compounds H-4-1 to H-4-2
1, compounds H-5-1 to H-5-5), JP-A-2001-
The substituted alkene derivative represented by the general formula (1) described in Japanese Patent No. 125224 (specifically, [Chemical Formula 1
0] to [Chemical Formula 55]).

The contrast increasing agent is water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide. , Dimethyl sulfoxide, methyl cellosolve, etc. Also, by well-known emulsification and dispersion method, it is dissolved using an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone. However, an emulsified dispersion can be mechanically prepared and used. Alternatively, by a method known as a solid dispersion method, the powder of the contrast-increasing agent may be dispersed in a suitable solvent such as water by a ball mill, a colloid mill, or ultrasonic waves before use.

The contrast-increasing agent may be added to any layer on the image forming layer side of the support, but it is preferably added to the image forming layer or a layer adjacent thereto. The addition amount varies depending on the grain size of the silver halide grains, the halogen composition, the degree of chemical sensitization, the type of the inhibitor, etc., and is not uniform, but about 10 ^{-6 to} 1 mol per 1 mol of silver, especially 1
The range of 0 ^-5 to 10 ^-1 mol is preferable.

In the present invention, in order to form a super-high contrast image, a contrast enhancing agent may be used in combination with the above contrast enhancing agent. For example, amine compounds described in US Pat. No. 5,545,505, specifically AM-1 to AM-5,
Hydroxamic acids described in US Pat. No. 5,545,507, specifically HA-1 to HA-11, acrylonitriles described in US Pat. No. 5,545,507, specifically CN-1 to CN-13, hydrazine compounds described in U.S. Pat. No. 5,558,983, specifically CA-1 to CA-6, JP-A-9-297.
Onium salts described in Japanese Patent No. 368, specifically A-
1 to A-42, B-1 to B-27, C-1 to C-14 and the like can be used.

In a heat-developable image recording 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 image forming layer containing photosensitive silver halide is 5 mmol or less, and further 1 mmo per mol of silver.
It is preferably 1 or less.

In the heat-developable image recording material of the present invention, it is preferable to use an acid formed by hydration of diphosphorus pentaoxide or a salt thereof in combination with a contrast-increasing agent. Examples of the acid formed by hydration of diphosphorus pentoxide or a salt thereof include metaphosphoric acid (salt), pyrophosphoric acid (salt), orthophosphoric acid (salt), triphosphoric acid (salt),
Examples include tetraphosphoric acid (salt) and hexametaphosphoric acid (salt).
Particularly preferably used acids formed by hydration of diphosphorus pentaoxide or salts thereof are orthophosphoric acid (salt) and hexametaphosphoric acid (salt), and specific salts include sodium orthophosphate, sodium dihydrogen orthophosphate, Examples include 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 to the image forming layer from the viewpoint of exhibiting a desired effect in a small amount. The amount of the acid formed by hydration of diphosphorus pentoxide or a salt thereof (application amount per 1 m ^{2 of the} heat-developable image recording material) may be a desired amount depending on the performance such as sensitivity and fog, but is 1 to
Preferably ^{500mg / m 2, 0.5~100mg / m} 2 is more preferable.

The heat-developable image recording material of the present invention preferably contains a reducing agent for the organic silver salt. The reducing agent for the organic silver salt 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 5 to 5 with respect to 1 mol of silver on the surface having the image forming layer.
The content is preferably 0 mol, and more preferably 10 to 40 mol. The reducing agent-containing layer may be any layer on the side having the image forming layer. When added to layers other than the image forming layer, 10 to 50 m per 1 mol of silver
It is preferable to use a large amount of ol. Further, the reducing agent may be a so-called precursor that is derivatized so as to have an effective function only during development.

In the heat-developable image recording material using an organic silver salt, a wide range of reducing agents are used in JP-A-46-6074, JP-A-47-1238, JP-A-47-33621 and JP-A-49-46427. , Ibid. 49-115540
No. 50-14334, No. 50-3611.
No. 0, No. 50-147711, No. 51-32
No. 632, No. 51-32324, No. 51-5.
No. 1933, No. 52-84727, No. 55-
No. 108654, No. 56-146133, No. 57-82828, No. 57-82829,
JP-A-6-3793, U.S. Pat. No. 3,679,4
No. 26, No. 3,751,252, No. 3,751,255, No. 3,761,270
No. 3,782,949, No. 3,782,949
839,048, 3,928,686, 5,464,738, German Patent 2,321,328, European Patent 692,73.
No. 2 specification and the like. For example, phenylamido oxime, 2-thienylamido oxime and p-
Amidooximes such as phenoxyphenylamidooxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehyde azine; such as the combination of 2,2′-bis (hydroxymethyl) propionyl-β-phenylhydrazine and ascorbic acid. A combination of an aliphatic carboxylic acid aryl hydrazide and ascorbic acid; a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine (eg hydroquinone and bis (ethoxyethyl) hydroxylamine, piperidinohexose reductone or formyl. −
4-methylphenylhydrazine combination); hydroxamic acid such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-alininehydroxamic acid; combination of azine and sulfonamidephenol (eg phenothiazine and 2,6-dichloro). -4-benzenesulfonamidephenol); ethyl-α-
Cyano-2-methylphenylacetate, ethyl-α-
Α-Cyanophenylacetic acid derivatives such as cyanophenylacetate; 2,2′-dihydroxy-1,1′-binaphthyl, 6,6′-dibromo-2,2′-dihydroxy-
1,1'-binaphthyl and bis (2-hydroxy-1)
Bis-β-naphthol as exemplified by -naphthyl) methane; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (for example, 2,4-dihydroxybenzophenone or 2 ', 4'-dihydroxyacetophenone) Combinations; 5-pyrazolones such as 3-methyl-1-phenyl-5-pyrazolone; as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone. Reducton; 2,
Sulfonamide phenol reducing agents such as 6-dichloro-4-benzenesulfonamidephenol and p-benzenesulfonamidephenol; 2-phenylindane-1,3-dione and the like; 2,2-dimethyl-7-ter
a chroman such as t-butyl-6-hydroxychroman;
2,6-dimethoxy-3,5-dicarbethoxy-1,
1,4-dihydropyridines such as 4-dihydropyridine; bisphenols (eg, 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, ascorbyl stearate, etc.); and aldehydes and ketones such as benzyl and biacetyl; 3-pyrazolidone and certain indane-1,3
-Dione; chromanol (tocopherol, etc.) and the like. Particularly preferred reducing agents are bisphenol,
It is chromanol.

When the 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 emulsion dispersion. Dispersion of solid fine particles is performed by a known refining means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). Further, a dispersion aid may be used when dispersing the solid fine particles.

In the present invention, as a development accelerator, JP-A-200
Phenol derivatives represented by the formula (A) described in JP-A-0-267222 are preferably used. The phenol derivative represented by the formula (A) exhibits a strong development promoting effect when used in combination with the reducing agent. Specifically, A-1 to A-54 described in the publication are preferably used. The phenol derivative represented by the formula (A) is preferably used in the range of 0.01 to 100 mol, and more preferably in the range of 0.1 to 20 mol with respect to 1 mol of the reducing agent.

The phenol derivative represented by the formula (A) may be added to the layer on the image forming layer side of the support, that is, the image forming layer or any other layer on this layer side. It is preferably added to the contained layer. The phenol derivative represented by the formula (A) may be added by any method such as an aqueous solution, an organic solvent solution, a powder, a solid fine particle dispersion, or an emulsion dispersion. The solid fine particles are dispersed by a known refining means (for example, ball mill, vibrating ball mill, sand mill,
Colloid mill, jet mill, roller mill, etc.). Further, a dispersion aid may be used when dispersing the solid fine particles.

Inclusion of additives known as "toning agents" for improving the image may increase the optical density. Further, the toning agent may be advantageous in forming a black silver image. Toning agent is 1 m silver on the side with the image forming layer
The amount is preferably 0.1 to 50 mol, and more preferably 0.5 to 20 mol per ol. Further, the toning agent may be a so-called precursor which is derivatized so as to have an effective function only during development. In a heat-developable image recording material using an organic silver salt, a wide range of color toning agents are disclosed in JP-A-46-6077 and 47-10.
282, 49-5019, and 49-50.
20 gazette, the same 49-91215 gazette, the same 49-91.
No. 215, No. 50-2524, No. 50-32
No. 927, No. 50-67132, No. 50-6.
No. 7641, No. 50-114217, No. 51
No. 3223, No. 51-27923, and No. 52
No. 14788, No. 52-99813, and No. 5
No. 3-1020, No. 53-76020, No. 5
No. 4-156524, No. 54-156525, No. 61-183642, JP-A-4-5684.
No. 8, Japanese Patent Publication No. 49-10727, No. 54-2.
0333, U.S. Pat. No. 3,080,254, No. 3,446,648, and No. 3,78.
No. 2,941, No. 4,123,282, No. 4,510,236, British Patent No. 1,
380,795, Belgian Patent No. 841,91
No. 0 specification and the like. Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazolin-5-one, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinedione. Cyclic imides such as; naphthalimide (eg N-hydroxy-1,8-naphthalimide); cobalt complex (eg cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4-triazole, 2,4 -Mercaptans exemplified by dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,4-thiadiazole; N- (aminomethyl) aryldi Carboximide, (for example, (N, N-dimethyl Aminomethyl) phthalimide and N, N- (dimethylaminomethyl) - naphthalene-2,3-dicarboximide); and blocked pyrazole, isothiuronium derivatives and certain photobleaching agents (e.g., 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, a phthalazinone derivative or a metal salt, or 4- (1-naphthyl) phthalazinone, 6-chlorophthala Derivatives such as dinone, 5,7-dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione; phthalazinone and phthalic acid derivatives (eg phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachloro) Phthalazine, a phthalazine derivative (eg, 4- (1-naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine, 6-isobutylphthalazine, 6-t).
derivatives such as ert-butylphthalazine, 5,7-dimethylphthalazine, and 2,3-dihydrophthalazine)
Or a metal salt; phthalazine and a derivative thereof and a phthalic acid derivative (for example, phthalic acid, 4-methylphthalic acid,
4-nitrophthalic acid and tetrachlorophthalic anhydride, etc.); quinazolinedione, benzoxazine or naphthoxazine derivatives; function not only as a color-modifying agent but also as a source of halide ions for in situ silver halide formation Rhodium complexes such as ammonium hexachlororhodium (III), rhodium bromide, rhodium nitrate and hexachlororhodium (II
I) Potassium acid and the like; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide;
Benzoxazines such as 1,3-benzoxazine-2,4-dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione -2,4-dione; pyrimidine and asymmetric-triazine (for example, 2,4-dihydroxypyrimidine, 2-hydroxy-4-aminopyrimidine and the like), azauracil, and tetraazapentalene derivative (for example, 3,6-dimercapto). -1,4-diphenyl-1H, 4H-2,3a, 5,6a-tetraazapentalene, and 1,4-di (o-chlorophenyl)
-3,6-dimercapto-1H, 4H-2,3a, 5
6a-tetraazapentalene) and the like.

In the present invention, a color tone adjusting agent is disclosed in JP-A-2000-
The phthalazine derivative represented by the general formula (F) described in Japanese Patent No. 35631 is preferably used. Specifically, A-1 to A-10 described in the publication are preferably used.

When the toning agent is used in the present invention, it may be added by any method such as solution, powder and solid fine particle dispersion. Dispersion of solid fine particles is performed by a known refining means (for example, ball mill, vibrating ball mill, sand mill, colloid mill, jet mill, roller mill, etc.). Further, a dispersion aid may be used when dispersing the solid fine particles.

The film 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. From the viewpoint of reducing the film surface pH, it is preferable to use an organic acid such as a phthalic acid derivative, a non-volatile acid such as sulfuric acid, or a volatile base such as ammonia for adjusting the film surface pH. Ammonia is particularly volatile so that it can be removed before the coating step or heat development, which is preferable for achieving a low film surface pH. The method for measuring the film surface pH is described in paragraph No. 0123 of JP-A No. 2000-284399.

In the heat-developable image recording material of the present invention, the silver halide emulsion or / and the organic silver salt are further protected against the formation of additional fog by the antifoggant, the stabilizer and the stabilizer precursor. In addition, it is possible to stabilize against a decrease in sensitivity during stock storage. Suitable antifoggants that can be used alone or in combination,
Stabilizers and stabilizer precursors are described in US Pat. No. 2,131,
Thiazonium salts described in U.S. Pat. No. 038 and 2,694,716, U.S. Pat. No. 2,886,43.
No. 7, and No. 2,444,605, azaindene, US Pat. No. 2,728,663, mercury salts, and US Pat. No. 3,287,135. Urazol, US Pat. No. 3,235,6
52, sulfocatechol, British Patent No. 6
Oxime, nitrone, nitroindazole described in US Pat. No. 23,448, polyvalent metal salts described in US Pat. No. 2,839,405, US Pat. No. 3,220,83.
The thiuronium salts described in US Pat. No. 9,639, and US Pat. Nos. 2,566,263 and 2,597,
915, palladium, platinum and gold salts,
U.S. Pat. No. 4,108,665 and 4,
Halogen-substituted organic compounds described in 442, 202, U.S. Pat. Nos. 4,128,557 and 4,137,079, 4,138,365 and 4 , 459,350 and the phosphorus compounds described in U.S. Pat. No. 4,411,985.

The heat-developable image recording material of the present invention may contain benzoic acids for the purpose of increasing sensitivity and preventing fog. The benzoic acid used in the present invention may be any benzoic acid derivative, but examples of preferable structures include US Pat. Nos. 4,784,939 and 4,152,160.
Specification, JP-A-9-329863, and JP-A-9-32.
The compounds described in 9864, 9-281637 and the like can be mentioned. The benzoic acid may be added to any layer of the heat-developable image recording material, but it is preferably added to the layer having the image forming layer, and more preferably to the organic silver salt-containing layer. The benzoic acid may be added at any step of the coating solution preparation, and when it is added to the organic silver salt-containing layer, it may be any step from the preparation of the organic silver salt to the preparation of the coating solution, but after the preparation of the organic silver salt. Therefore, immediately before coating is preferable. The benzoic acid may be added by any method such as powder, solution and fine particle dispersion. Also, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent, and a toning agent. Any amount of benzoic acid may be added, but it is 1 per 1 mol of silver.
× 10 ⁻⁶ mol to 2 mol is preferable, and 1 × 10 ⁻³ mo is preferred.
1 to 0.5 mol is more preferable.

Although not essential to the practice of the 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 addition amount of mercury used in the present invention is 1 mol of coated silver.
Preferably 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mo per liter
1, more preferably 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ m
It is in the range of ol.

The antifoggant particularly preferably used in the present invention is an organic halide, for example, US Pat. Nos. 3,874,946 and 4,756,999.
No. 5,340,712, No. 5,340,712
369,000, 5,464,737, JP-A-50-120328, and JP-A-50-
No. 137126, No. 50-89020, No. 5
0-119624, 59-57234,
JP-A-7-2781, JP-A-7-5621, JP-A-9-160164 and JP-A-9-160167,
No. 10-197988, No. 9-244177, No. 9-244178, No. 9-160167, No. 9-319022, and No. 9-258367.
No. 9-265150, No. 9-31902
No. 2, gazette 10-197989, gazette 11-24.
No. 2304, No. 2000-2963, No. 2000-112070, No. 2000-284.
412, JP 2000-284399 A, JP 2000-284410 A, JP 2001-33 A.
Examples thereof include compounds described in JP-A No. 911 and JP-A No. 2001-5144. Among these, particularly preferred organic halides are 2-tribromomethylsulfonylquinoline described in JP-A-7-2781, JP-A-2
2-tribromomethylsulfonylpyridine described in JP-A-001-5144, compounds P-1 to P-31 described in JP-A-2000-112070, and JP-A-2000-
Compounds P-1 to P-73 described in Japanese Patent No. 284410, and P-1 to P-1 described in Japanese Patent Laid-Open No. 2001-33911.
Compounds of P-25 and P′-1 to P′-27, JP-A-200-200
Compounds P-1 to P-118 described in JP-A No. 0-284399, phenyltribromomethylsulfone, and 2-naphthyltribromomethylsulfone. The addition amount of the organic halide is a mol amount (mol
/ MolAg), preferably 1 × 10 ^{−5 to 2} m
ol / molAg, more preferably 5 × 10 ^{−5 to 1} mo
1 / molAg, more preferably 1 × 10 ^{−4 to} 5 × 1
It is 0 ⁻¹ mol / mol Ag. These may be used alone or in combination of two or more.

Further, Japanese Patent Laid-Open No. 2000-284399.
The salicylic acid derivative represented by the formula (Z) described in 1.
It is preferably used as an inhibitor. Specifically, the publication
(A-1) to (A-60) described in (4) are preferably used.
It The addition amount of the salicylic acid derivative represented by the formula (Z) is
Mol amount per mol of Ag (mol / mol Ag)
, Preferably 1 × 10^-Five~ 5 x 10^-1mol /
molAg, more preferably 5 × 10^-Five~ 1 x 10^-1m
ol / molAg, more preferably 1 × 10 ^-Four~ 5x
10^-2It is mol / molAg. These are only one
You may use, or may use 2 or more types together.

Formalin scavenger is effective as an antifoggant preferably used in the present invention. For example, the compound represented by the formula (S) described in JP-A-2000-221634 and its exemplified compound (S-
1) to (S-24).

The antifoggant used in the present invention is water or a suitable organic solvent such as alcohols (methanol, ethanol, propanol, fluorinated alcohol), ketones (acetone, methyl ethyl ketone), dimethylformamide, dimethyl sulfoxide, methyl. It can be used by dissolving it in cellosolve or the like. Further, by well-known emulsion dispersion method, dibutyl phthalate, tricresyl phosphate, oil such as glyceryl triacetate or diethyl phthalate,
It can be dissolved by using an auxiliary solvent such as ethyl acetate or cyclohexanone to mechanically prepare an emulsified dispersion for use. Alternatively, the powder can be dispersed in water by a method known as a solid dispersion method by a ball mill, a colloid mill, a sand grinder mill, a manton golin, a microfluidizer, or ultrasonic waves before use.

The antifoggant used in the present invention may be added to a layer on the image forming layer side of the support, that is, the image forming layer or any other layer on this layer side. It is preferably added to the layer adjacent thereto.
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 heat-developable image recording material of the present invention may contain a mercapto compound, a disulfide compound or a thione compound for the purpose of suppressing or accelerating the development to control the development and improving the storage stability before and after the development. . When the mercapto compound is used in the present invention, it may have any structure, but Ar-SM, Ar-SS-
Those represented by Ar are preferable. In the formula, M is a hydrogen atom or an alkali metal atom, Ar is at least one nitrogen,
An aromatic ring or condensed aromatic ring having a sulfur, oxygen, selenium or tellurium atom. Preferably, the heteroaromatic ring is benzimidazole, nafusuimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotelrazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine. , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring may be, for example, halogen (eg Br and Cl), hydroxy, amino, carboxy, alkyl (eg having 1 or more carbon atoms, preferably 1 to 4 carbon atoms), alkoxy ( For example, having one or more carbon atoms, preferably having 1 to 4 carbon atoms) and aryl (which may have a substituent) selected from the group of substituents. 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,
4-triazole, 4,5-diphenyl-2-imidazolthiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2-mercaptoquinoline, 8-mercaptopurine, 2-mercapto-
4 (3H) -quinazolinone, 7-trifluoromethyl-
4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino-6-hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4 -Thiadiazole, 3
-Amino-5-mercapto-1,2,4-triazole, 4-hydroxy-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 thereof include N ′-{3- (5-mercaptotetrazolyl) phenyl} urea and 2-mercapto-4-phenyloxazole, but the present invention is not limited thereto. The addition amount of these mercapto compounds is 0.0001 to 1.0 mol per mol of silver in the image forming layer.
Is preferable, and more preferably 0.001 to 0.3 mol per mol of silver.

The image forming layer is preferably prepared by applying an aqueous coating solution and then drying it. 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.

Various supports can be used in the heat-developable image recording material of the present invention. Typical supports are polyethylene terephthalate, polyethylene naphthalate,
Such as polyester, cellulose nitrate, cellulose ester, polyvinyl acetal, syndiotactic polystyrene, polycarbonate, a paper support coated on both sides with polyethylene, and the like. Of these, biaxially stretched polyester, especially polyethylene terephthalate (PE
T) is preferable in terms of strength, dimensional stability, chemical resistance and the like. The thickness of the support is 50 in terms of the base thickness excluding the undercoat layer.
It is preferably about 200 μm. The support used in the heat-developable image recording material of the present invention is described in JP-A-10-48772.
JP-A-10-10676, JP-A-10-
10677, JP-A-11-65025, JP-A-11-138648, to alleviate the internal strain remaining in the film during biaxial stretching and to eliminate the heat shrinkage strain generated during the heat development treatment. To 130-185
Polyester, especially polyethylene terephthalate, which has been heat-treated in the temperature range of ° C is preferably used.

12 of the support after such heat treatment
The dimensional change rate by heating at 0 ° C. for 30 seconds is −0.03% to + 0.01% in the machine direction (MD) and 0 in the transverse direction (TD).
It is preferably 0.04%.

Both sides of the support are provided on both sides with JP-A-64-2054.
No. 4, JP-A-1-180537, and JP-A-1-180537.
209443, JP-A 1-285939,
JP-A-1-296243, JP-A-2-24649
Japanese Patent Application Laid-Open No. 24-48648, Japanese Patent Application Laid-Open No. 2-18
No. 4844, No. 3-109545, No. 3-137637, No. 3-141346, No. 3-141347, No. 4-96.
No. 055, U.S. Pat. No. 4,645,731, Japanese Patent Laid-Open No. 4-68344, Registration No. 2,557,
641 publication, P2 right column, 20th line to P3 right column, 30th line, paragraph numbers 0020 to 0 of JP 2000-39684A.
037, Japanese Patent Application No. 2000-47083, paragraph number 0
It is preferable to provide a layer containing a vinylidene chloride copolymer containing 70% by mass or more of the repeating unit of the vinylidene chloride monomer described in 063 to 0080.

When the vinylidene chloride monomer content is less than 70% by mass, sufficient moisture resistance cannot be obtained, and the dimensional change over time after heat development becomes large. Further, the vinylidene chloride copolymer preferably contains a repeating unit of a carboxyl group-containing vinylden monomer as a constitutional repeating unit other than the vinylidene chloride monomer. The inclusion of such a constitutional repeating unit causes the polymer (polymer) to crystallize only with the vinylden chloride monomer,
This is because it becomes difficult to form a uniform film when the moisture-proof layer is applied, and the carboxyl group-containing vinylden monomer is indispensable for stabilizing the polymer. The vinylidene chloride copolymer has a weight average molecular weight of 450.
00 or less, more preferably 10,000 to 45,000. When the molecular weight is large, the adhesion between the vinylidene chloride copolymer layer and the support layer such as polyester is deteriorated.

The content of the vinylidene chloride copolymer is 0.3 μm or more, preferably 0.3 μm, as the total film thickness per one side of the layer containing the vinylidene chloride copolymer.
Is in the range of ˜4 μm.

The vinylidene chloride copolymer layer may be provided on the undercoat layer as the first layer or the undercoat layer directly provided on the support. Usually, one layer is provided on each side, but in some cases, two or more layers may be provided. When a multi-layered structure having two or more layers is used, the total amount of vinylidene chloride copolymer may be within the range of the present invention. In addition to vinylidene chloride copolymer,
You may contain a crosslinking agent, a matting agent, etc.

If necessary, the support may be coated with a vinylidene chloride copolymer layer or an undercoat layer containing SBR, polyester, gelatin or the like as a binder. These undercoat layers may have a multi-layered structure and may be provided on one side or both sides of the support. The general thickness (per layer) of the undercoat layer is 0.01 to 5 μm, more preferably 0.05 to 1 μm.

The heat-developable image recording material of the present invention has the purpose of reducing dust adhesion, preventing the occurrence of static marks, and preventing conveyance defects in the automatic conveying process.
Antistatic can be achieved by using the conductive metal oxides and / or fluorine-based surfactants described in paragraphs 0040 to 0051 of the publication. As the conductive metal oxide,
U.S. Pat. No. 5,575,957, JP-A-11-
No. 223901, paragraphs 0012 to 0020, needle-shaped conductive tin oxide doped with antimony,
The fibrous tin oxide doped with antimony described in JP-A-4-29134 is preferably used.

Surface Resistivity of Metal Oxide-Containing Layer (Surface Resistance
Rate) is 10 in an atmosphere of 25 ° C. and 20% relative humidity.¹²Ω or less
under. Preferably 10¹¹Ω or less is preferable. This makes it better
Antistatic property can be obtained. The lower limit of surface resistivity at this time is
Although not particularly limited, usually 10 ⁷It is about Ω.

The surfactant used in the present invention is described below. Surfactants are classified into dispersants, coating agents, wetting agents, antistatic agents, photographic control agents, etc., depending on the purpose of use, but those objects can be achieved by appropriately using the surfactants described below. it can. 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 are:
Polyoxyethylene, polyoxypropylene, polyoxybutylene, polyglycidyl or sorbitan is a surfactant having a nonionic hydrophilic group, specifically, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxy Examples thereof include ethylene-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. .

The anionic surfactants include carboxylates, sulfates, sulfonates and phosphates,
Typical examples are fatty acid salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl sulfonates, α-olefin sulfonates, dialkyl sulfosuccinates, α-sulfonated fatty acid salts, N-methyl-N-oleyl taurine. , Petroleum sulfonate, alkyl sulfate, sulfated oil, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate, polyoxyethylene styrenated phenyl ether sulfate, alkyl phosphate, polyoxyethylene alkyl Examples thereof include ether phosphates and naphthalene sulfonate formaldehyde condensates.

As the cationic surfactant, an amine salt,
Examples thereof include quaternary ammonium salts and pyridinium salts. First to third fatty amine salts, quaternary ammonium salts (tetraalkylammonium salts, trialkylbenzylammonium salts, alkylpyridinium salts, alkylimidazolium salts, etc.) ) Can be mentioned.

The betaine-based surfactants include carboxybetaine, sulfobetaine, N-trialkyl-N-carboxymethylammonium betaine and N-.
Trialkyl-N-sulfoalkylene ammonium betaine and the like.

These surface active agents are described in "Application of surface active agents (Koushobo, Takao Karime, published September 1, 1980)."
It is described in. In the present invention, the preferred amount of the surfactant is not particularly limited as long as it is used, as long as the desired surfactant properties are obtained. The coating amount of the fluorine-containing surfactant is 250 mg / m ^{2 or} more.
0.01 mg is preferred.

Specific examples of the surfactant will be described below, but the surfactant is not limited thereto (wherein —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) naphthalene sulfonate WA-5: Sodium tri (isobutyl) naphthalene sulfonate WA-6: Sodium dodecyl sulfate WA-7: α-sulfa succinic acid di (2-ethylhexyl) ester sodium salt 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) WA -18: C ₈ F ₁₇ CH ₂ CH ₂ SCH ₂ CH ₂ CH ₂ COOLi WA-19: (C ₄ F ₉ ) COOCH ₂ CH (SO ₃ Na) COOCH ₂ CH ₂ (C ₄ F ₉ ) WA-20: C ₈ H ₁₇ COOCH ₂ CH (SO ₃ Na) COOCH ₂ CH ₂ (C ₄ F ₉ )

In the present invention, the image forming layer, the protective layer for the image forming layer, the undercoat layer and the back layer are disclosed in JP-A-11-84.
Paragraph Nos. 0204 to 0208 of Japanese Patent No. 573, Japanese Patent Application No. 20
00-47083, paragraph numbers 0240-024
1, JP-A-8-278595, JP-A-7-102
A dye can be contained for the purpose of preventing halation as described in JP-A-179 and JP-A-9-509503.

Various dyes and pigments can be used in the image forming layer from the viewpoint of improving the color tone and preventing irradiation. Any dyes and pigments may be used in the image forming layer. For example, compounds described in paragraph No. 0297 of JP-A No. 11-119374 can be used. As a method for adding these dyes, any method such as a solution, an emulsion, a solid fine particle dispersion, or a state of being mordanted with a polymer mordant may be used. The amount of these compounds used is determined depending on the desired absorption amount, but it is generally preferable to use it in the range of 1 × 10 ⁻⁶ g to 1 g per 1 m ² .

When the antihalation dye is used in the present invention, the dye has a desired absorption in a desired range, has a sufficiently small absorption in the visible region after the treatment, and has a preferable absorbance spectrum shape of the back layer. Any compound may be used as long as it is possible. For example, the compound described in paragraph No. 0300 of JP-A No. 11-119374 can be used. Further, as described in Belgian Patent No. 733,706, a method of decreasing the density by a dye by heat erasing, and the density is decreased by light erasing as described in JP-A-54-17833. It is possible to use such a method.

The photographic emulsion coating solution, which is a viscous solution containing silver halide and containing gelatin as a base material, has been used in the past because bubbles were dissolved and disappeared in the solution only by feeding under pressure. Even when the pressure is returned to atmospheric pressure, bubbles hardly precipitate. However, in the case of the image forming layer coating solution containing the organic silver salt dispersion and the polymer latex, which are preferably used in the present invention, defoaming tends to be insufficient only by pressure feeding, so that a gas-liquid interface does not occur. It is preferable to defoam by applying ultrasonic vibration while feeding the solution.

In the present invention, defoaming of the coating liquid is performed by degassing under reduced pressure before applying the coating liquid, and further 1.5 kg / cm ²
It is preferable to use a system in which ultrasonic vibration is applied while continuously feeding the liquid while maintaining the above pressurized state and preventing the gas-liquid interface from occurring. Specifically, Japanese Examined Patent Publication No. 55-6405 (4
The method described in page 20, line 7 to page 7, line 11) is preferred. As a device for performing such defoaming, Japanese Patent Laid-Open No. 2000-2000
Embodiment of Japanese Patent Publication No. -98534 The structure shown in FIG. 3 can be preferably used.

As the pressurizing condition, 1.5 kg / cm ² or more,
It is preferably 1.8 kg / cm ² or more. The upper limit is not particularly limited, but is usually about 5 kg / cm ² . The sound pressure of the ultrasonic waves applied is 0.2 V or higher, preferably 0.
It is 5 V to 3.0 V, and it is generally preferable that the sound pressure is high. However, if the sound pressure is too high, a high temperature is partially caused by the capitation, which causes fog. The frequency is not particularly limited, but usually 10 kHz or higher, preferably 20
kHz to 200 kHz. Note that the depressurization degassing refers to hermetically depressurizing the inside of the tank (usually, the preparation tank or the storage tank) to increase the bubble diameter in the coating solution, depressurizing the buoyancy, and degassing. Decompression condition is -200
mmHg or lower pressure condition, preferably -2
The pressure condition is 50 mmHg or lower, and the lowest pressure condition is not particularly limited, but is usually -800 mmH.
It is about g. Decompression time is 30 minutes or more, preferably 45
There is no particular upper limit for more than a minute.

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. However, for the purpose of improving productivity, these plural layers may be water-based. At the same time, multi-layer coating is performed. Examples of the coating method include extrusion coating, slide bead coating, curtain coating, and the like, and the slide bead coating method disclosed in FIG. 1 of the specification of JP 2000-2964 A is particularly preferable. In the case of a silver halide photographic light-sensitive material using gelatin as the main binder, it is rapidly cooled in the first drying zone provided downstream of the coating die, resulting in gelatinization of gelatin, and the coating film is cooled and solidified. . The coating film which has been solidified by cooling and stopped flowing is guided to the subsequent second drying zone, and the solvent in the coating liquid is volatilized in the subsequent drying zone to form a film. As the drying method after the second drying zone, an air loop method in which a jet is blown from a U-shaped duct onto a roller-supported support body, or a support body is wound around a cylindrical duct in a spiral shape, and is dried. A firewood method (air floating method) and the like can be mentioned.

With a coating solution in which the main component of the binder is a polymer latex, the flow of the coating solution cannot be stopped by rapid cooling, so pre-drying may be insufficient only in the first drying zone. In this case, a drying method such as a silver halide photographic light-sensitive material causes unevenness in flow and unevenness in drying, so that serious defects are likely to occur on the coated surface.

A preferred drying method in the present invention is at least 1/4 or more of the constant rate drying period regardless of the first drying zone and the second drying zone as described in JP-A-2000-2964. Is preferably a method of drying in a horizontal drying zone. The support may be conveyed immediately after coating until it is guided to the horizontal drying zone either horizontally or not, and the rising angle of the coating machine with respect to the horizontal direction may be 0 to 70 °. . Further, the horizontal drying zone in the present invention does not mean horizontal transportation as long as the support is vertically transported within ± 15 ° with respect to the horizontal direction of the coating machine. The dry air in the constant rate drying period has a wind speed of 1 to 1 on the surface of the coating liquid film.
It is preferable to dry at 30 m / s, preferably 2 to 20 m / s. More preferably, the first drying zone is a low speed air drying area, and the wind speed is 15 m / s or less, preferably 2 to 10 m / s on the support surface for a time within 1/2 of the constant rate drying period in this area. In the second drying zone thereafter, the wind speed is 5 to 30 m / s, preferably 10 to 20 m / s, so that there is no unevenness in drying and the productivity can be improved.

The constant rate drying in the present invention means a drying process in which the liquid film temperature is constant and all the inflowing heat quantity is used for evaporation of the solvent. Decreasing rate drying means that at the end of drying, the drying rate decreases due to various factors (moisture transfer inside the material is rate-determining, evaporation surface receding, etc.), and the heat applied is also used to raise the liquid film temperature. Means the drying process performed. When the constant rate drying is finished, the drying proceeds sufficiently until the flow stops, so that a drying method such as a silver halide photographic light-sensitive material can also be adopted.

The preferable drying conditions in the present invention are the minimum film forming temperature (MFT) of the polymer latex in which the liquid film surface temperature at the constant rate drying is used as the drying conditions for forming the image forming layer and / or the protective layer. As described above, the temperature is usually 25 ° C to 45 ° C in most cases due to the limitation of manufacturing equipment.
Further, the dry-bulb temperature at the time of rate reduction drying is preferably a temperature lower than Tg of the support used (usually 80 ° C. or lower in the case of PET). The liquid film surface temperature in the present invention refers to the surface temperature of the coating liquid film applied to the support, and the dry-bulb temperature means the temperature of the dry air in the drying zone.

When the drying is carried out under the condition that the surface temperature of the liquid film during constant rate drying becomes low, the drying tends to be insufficient. For this reason, the film-forming property of the protective layer is remarkably reduced, and cracks are likely to occur on the film surface. In addition, the film strength becomes weak, and serious problems such as scratches are likely to occur during conveyance by an exposure machine or a heat development machine. Further, when excessive heat higher than the Tg of the support (base) is applied, the dimensional stability, curl resistance, etc. of the heat-developable image recording material deteriorate.

The winding after drying is preferably carried out under the conditions of a temperature of 20 to 30 ° C. and a relative humidity of 45 ± 20%. Good, or inside. Further, when the processed form is a roll product, it is also preferable to use a roll form wound on the side opposite to the wound form at the time of processing in order to remove the curl generated in the wound form. The environmental conditions during packaging of the heat-developable image recording material are 20 to 30 ° C. and a relative humidity of 20 to 30 ° C.
The range of 65% is preferable, and the relative humidity in the packaging bag is 20
It is preferably controlled in the range of 55% (measured at 25 ° C). The heat-developable image recording material of the present invention is disclosed in JP-A-6-17.
5291, JP-A-6-214350, JP-A-7-92618, JP-A-8-62783, JP-A-8-254793, and JP-A-11-32.
7089, JP 2000-181017 A,
JP-A-2000-171942, JP-A-2000-
It can be packaged by using the packaging material and the packaging method described in JP206653B and JP 2001-13632A.

In the image forming method of the present invention, the heat-developable image recording material is first exposed to light having a wavelength of 750 to 800 nm. Used for the exposure exposure apparatus capable of exposure exposure time is less than 10 ^-7 seconds laser diode (L
An exposure device using D) as a light source is used. Any of these light sources may be used as long as it can generate light having an electromagnetic wave spectrum in a target wavelength range. For example, a dye laser, a gas laser, a solid-state laser, a semiconductor laser and the like can be used, but the semiconductor laser is particularly preferably used from the viewpoint of space saving and cost saving.

In the image forming method of the present invention, it is preferable to expose the heat-developable image recording material by overlapping the light beams of the light source. The overlap means that the sub-scanning pitch width is smaller than the beam diameter. The overlap refers to, for example, the beam diameter and the full width at half maximum (FWH) of the beam intensity.
When expressed by M), it can be quantitatively expressed by FWHM / sub-scanning pitch width (overlap coefficient). In the present invention, this overlap coefficient is preferably 0.2 or more.

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, etc. can be used. Also,
The channel of the light source may be a single channel or a multi-channel, but a multi-channel equipped with two or more laser heads is preferable in that high output can be obtained and the writing time can be shortened. Particularly, in the case of the cylindrical outer surface type, a multi-channel in which several to several tens or more laser heads are mounted is preferably used.

The heat-developable image recording material to be exposed is
When the haze at the time of exposure is low, interference fringes tend to occur, so it is preferable to prevent this. A technique for preventing the occurrence of interference fringes is disclosed in Japanese Patent Laid-Open No. 11354/1993.
The technique disclosed in Japanese Patent Publication No. 8 and the like, in which laser light is obliquely incident on the heat-developable image recording material, and International Publication W
Methods using a multimode laser disclosed in O95 / 31754 and the like are known, and it is preferable to use these techniques.

The scanning system of the light source of the exposure apparatus preferably used in the present invention is the inner drum system (cylindrical inner surface scanning system). The exposure is performed by scanning the laser light generated from the laser diode through the polygon mirror (prism) onto the surface of the heat-developable image recording material conveyed to the inner drum portion. The exposure time in the main scanning direction is determined by the rotation speed of the polygon mirror and the inner diameter of the drum.
The main scanning speed on the surface of the heat-developable image recording material of the present invention is 50.
It is preferably 0 m / sec to 1500 m / sec. A more preferable main scanning speed is 630 m / sec to 1410 m / sec.

The heat-developable image recording material to be exposed is
When the haze at the time of exposure is low, interference fringes tend to occur, so it is preferable to prevent this. A technique for preventing the occurrence of interference fringes is disclosed in Japanese Patent Laid-Open No. 11354/1993.
The technique disclosed in Japanese Patent Publication No. 8 and the like, in which laser light is obliquely incident on the heat-developable image recording material, and International Publication W
Methods using a multimode laser disclosed in O95 / 31754 and the like are known, and it is preferable to use these techniques.

In the image forming method of the present invention, the heat-developable image recording material is exposed to light to form a latent image, and then developed by a heat developing machine having a preheating section, a heat developing section and a slow cooling section. . The development temperature by the heat developing machine is preferably 80 to 250 ° C, and more preferably 100 to 140 ° C. The total developing time by the heat developing machine is 1 to 18
It is preferably 0 seconds, more preferably 5 to 90 seconds. Further, the processing speed of the heat developing section by the heat developing machine is preferably 21 to 100 mm / sec, and 24
More preferably, it is ˜50 mm / sec.

The exposed heat-developable image recording material is
It is heated in the preheating section. The preheating section is provided for the purpose of preventing uneven processing due to dimensional change of the heat-developable image recording material during heat development. The heating in the preheating section is
It is desirable to set the temperature and time lower than the heat development temperature (for example, about 10 to 30 ° C. lower) and sufficient to evaporate the solvent remaining in the heat development image recording material. Body glass transition temperature (T
It is preferable to set the temperature higher than that of g) so that development unevenness does not occur. Generally, it is preferable to heat at 80 ° C. or higher and lower than 115 ° C. for 5 seconds or longer.

The photothermographic material which has been heated in the preheating section is subsequently heated in the heat developing section. In the image forming method of the present invention, the heat developing section is provided with heating members on the image forming layer side and the back layer side with respect to the conveyed heat developable image recording material, and a conveying roller is provided only on the image forming layer side. Prepare For example, when the heat-developable image recording material is conveyed with the image forming layer on the upper side, there is no conveyance roller on the lower side (back layer side of the heat-developable image recording material) with respect to the conveyance direction of the heat-developable image recording material. The transport roller is provided only on the side of the image forming layer of the heat developable image recording material. In the present invention, the heat developing section is configured as described above to prevent density unevenness and physical deformation.

In the heat development section, the heat development image recording material is heated by a heating member such as a heater. The heating temperature in the heat development section is a temperature sufficient for heat development, and is generally 110 ° C to 140 ° C. Since the heat-developable image recording material is exposed to a high temperature of 110 ° C. or higher in the heat-development section, some of the components contained in the material or some of the decomposed components by heat development may volatilize. . These volatile components cause uneven development, corrode the components of the thermal developing machine, and deposit at low temperature,
It is known that foreign matter may cause deformation of the screen, stains adhered to the screen, and various other adverse effects. As a method for eliminating these influences, a method is known in which a filter is installed in the heat developing machine and the air flow in the heat developing machine is optimally adjusted. These methods can be effectively used in combination. For example, International Publication WO95 / 30933, the same 97/2.
No. 1150 and Japanese Patent Publication No. 10-5000496, a filter cartridge having a first opening having bound absorbent particles for introducing volatile matter and a second opening for discharging volatile matter is contacted with a film. It is described to be used in a heating device for heating by heating. In addition, international publication WO96 / 12
In Japanese Patent No. 213 and Japanese Patent Publication No. 10-507403,
It is described to use a filter in which a heat conductive condensing collector and a gas absorbing particulate filter are combined. In the present invention, these can be preferably used. Also,
U.S. Pat. No. 4,518,845, Japanese Patent Publication No. 3-5
Japanese Patent No. 4331 describes a configuration including a device for removing vapor from a film, a pressurizing device for pressing the film against the heat transfer member, and a device for heating the heat transfer member. In addition, International Publication WO98 / 27458 discloses that a component that increases volatilization fog from a film is removed from the film surface. These can also be preferably used in the present invention.

The temperature distribution of heating in the preheating section and the heat developing section is preferably ± 1 ° C. or less,
It is more preferably 0.5 ° C. or lower.

The heat-developable image recording material heated in the heat developing section is then cooled in the slow cooling section. Cooling is preferably performed gradually so that the heat-developable image recording material is not physically deformed, and the cooling rate is preferably 0.5 to 10 ° C./sec.

An example of the constitution of the heat developing machine used in the image forming method of the present invention is disclosed in JP-A-2000-171935,
JP-A-2000-267226, JP-A-2001-2
The preheating described in JP-A-2024 is conveyed by an opposite roller, and the heat development processing section is arranged such that the side having the image forming layer is a roller.
A heat development processing apparatus is preferably used in which the back surface on the opposite side is slid to a smooth surface and is conveyed by driving.

In the image forming method of the present invention, exposure and heat development are carried out by an online system of an exposure device (plotter), an auto carrier and a heat developing device (processor). The auto carrier automatically conveys the exposed heat-developable image recording material to the processor (heat processor), and the conveyance mechanism may be any method such as a belt conveyer and a roller conveyer.
Roller transport is preferred. Further, it is preferable to provide a mechanism for the auto carrier so that heat does not enter from the heat developing machine side to the exposing device side. For example, there is a system in which air is blown into the exposing device and the heat developing device from the lower center of the auto carrier.

The heat-developable image recording material has, for example, a width of 5
A sheet-like member having a length of 50 to 650 mm and a length of 1 to 65 m is used, and a part or all of the sheet-like member is wound into a cylindrical core member with the image forming layer as the outer side and incorporated in a heat developing system.

When the heat-developable image recording material of the present invention is used as a mask after the heat development for producing a printing plate with a PS plate, the heat-developable image recording material after the heat development is applied to the PS plate in a plate making machine. Information for setting exposure conditions and information for setting plate-making conditions such as transport conditions for mask originals and PS plates are carried as image information. Therefore, the concentration (use amount) of the above-mentioned irradiation dye, halation dye, and filter dye is limited to read them. Since this information is read by the LED or laser, the 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. is used as a detector and bar code reader for detecting registration marks 670n.
A light source with a wavelength of m is used. Also, manufactured by Shimizu Manufacturing Co., Ltd.
6 as bar code reader for plate making machine APML series
A 70 nm light source is used. That is, when Dmin (minimum density) near 670 nm is high, the information on the film cannot be accurately detected, and a work error occurs in the plate making machine such as conveyance failure or exposure failure. Therefore, in order to read information with a light source of 670 nm, Dmin near 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 0.2
It is 5 or less. The lower limit is not particularly limited, but usually
It is about 0.10.

In the present invention, the exposure device used for imagewise exposure may be any device as long as it can perform exposure with an exposure time of less than 10 ⁻⁷ seconds. Generally, a laser diode (LD),
An exposure apparatus using a light emitting diode (LED) as a light source is preferably used. In particular, LD is more preferable in terms of high output and high resolution. Any of these light sources may be used as long as it can generate light having an electromagnetic wave spectrum in a target wavelength range. For example, as the LD, a dye laser, a gas laser, a solid laser, a semiconductor laser, or the like can be used.

[0151]

EXAMPLES The features of the present invention will be described more specifically below with reference to examples and comparative examples. Materials shown in the following examples,
The usage amount, ratio, processing content, processing procedure, etc. can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be limitedly interpreted by the following specific examples.

<Example 1><< Preparation of silver halide emulsion A >> 700 ml of water was treated with alkali-treated gelatin (calculated to have a calcium content of 2700 pp).
m or less) 11 g, potassium bromide 30 mg and sodium 4-methylbenzenesulfonate 1.3 g are dissolved,
The pH was adjusted to 6.5 at 40 ° C. Then silver nitrate 1
159 ml of an aqueous solution containing 8.6 g and 1 part of potassium bromide
mol / L, (NH ₄ ) ₂ RhCl ₅ (H ₂ O) 5 × 10
^-6 mol / L and K ₃ IrCl ₆ at 2 × 10 ^-5 mol / L
The aqueous solution containing L was added by the control double jet method over 6 minutes and 30 seconds while keeping the pAg at 7.7.
Then, 476 ml of an aqueous solution containing 55.5 g of silver nitrate,
1 mol / L potassium bromide and 2 × K ₃ IrCl ₆
Aqueous halogen salt solution containing 10 ⁻⁵ mol / L was added to pAg
2 by control double jet method while keeping at 7.7
It was added over 8 minutes and 30 seconds. Then, the pH was lowered to cause coagulation and sedimentation, desalting treatment, and 51.1 g of low-molecular weight gelatin having an average molecular weight of 15,000 (calcium content of 20 ppm or less) was added to adjust 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 obtained silver halide grains were heated to 60 ° C., 76 μmol of sodium benzenethiosulfonate was added per 1 mol of silver, 71 μmol of triethylthiourea was added after 3 minutes, and the mixture was aged for 100 minutes. −
After adding 5 × 10 ⁻⁴ mol of hydroxy-6-methyl-1,3,3a, 7-tetrazaindene and 0.17 g of compound A, the temperature was lowered to 40 ° C. Then, the temperature was kept at 40 ° C., and 4.7 × 10 ⁻² m was added to 1 mol of silver halide.
ol potassium bromide (added as an aqueous solution), 12.8x
10 ⁻⁴ mol of sensitizing dye A (added as ethanol solution) and 6.4 × 10 ⁻³ mol of compound B (added as methanol solution) were added with stirring, and after 20 minutes, 30
The preparation of Silver Halide Emulsion A was completed by rapidly cooling to ° C. The obtained silver halide emulsion A was used for preparing the following coating solution.

[0154]

[Chemical 1]

<< Preparation of Silver Behenate Dispersion A >> 87.6 kg of behenic acid (Edenor C22-85R, manufactured by Henkel), distilled water 423 L, 5 mol / L NaOH aqueous solution 49.2.
L, tert-butyl alcohol 120L, mixed,
The mixture was stirred at 5 ° C. for 1 hour for reaction to obtain a sodium behenate solution. Separately from this, 206.2 L of an aqueous solution of 40.4 kg of silver nitrate was prepared and kept at 10 ° C. 635
The reaction vessel containing L of distilled water and 30 L of tert-butyl alcohol was kept at 30 ° C., and while stirring, the total amount of the sodium behenate solution and the total amount of the silver nitrate aqueous solution were kept constant at 62 minutes, 10 seconds and 60 minutes, respectively. Added over minutes.
At this time, only the silver nitrate aqueous solution was added for 7 minutes and 20 seconds after the addition of the silver nitrate aqueous solution was started, and then the addition of the sodium behenate solution was started, and after the addition of the silver nitrate aqueous solution was completed, 9
Only the sodium behenate solution was added for 30 minutes. At this time, the temperature inside the reaction vessel was set to 30 ° C. and controlled so that the liquid temperature did not rise. Also,
The piping of the sodium behenate solution addition system was kept warm by steam tracing, and the liquid temperature at the outlet of the addition nozzle tip was 7
The amount of steam was controlled so as to be 5 ° C. Further, the piping of the addition system of the silver nitrate aqueous solution was kept warm by circulating cold water outside the double tube. The position of addition of the sodium behenate solution and the position of addition of the aqueous silver nitrate solution were symmetrically arranged around the stirring axis, and the height was adjusted so as not to come into contact with the reaction solution. After adding the sodium behenate solution, stir at the same temperature for 20 minutes and leave at 25 ° C.
The temperature dropped to. Then, the solid content was separated by centrifugal filtration, and the solid content was washed with water until the conductivity of the filtered water reached 30 μS / cm. The solid content thus obtained was stored as a wet cake without being dried. When the morphology of the obtained silver behenate particles was evaluated by electron microscopic photography, it was found to be a scaly crystal having an average projected area diameter of 0.52 μm, an average grain thickness of 0.14 μm, and a variation coefficient of 15% of the average sphere-equivalent diameter. It was

Next, a dispersion of silver behenate was prepared by the following method. Polyvinyl alcohol (Kuraray Co., Ltd., PVA) was used for a wet cake having a dry solid content of 100 g.
-217, average degree of polymerization: about 1700) (7.4 g) and water were added to adjust the total amount to 385 g, and then predispersed with a homomixer. Then, the pre-dispersed stock solution was dispersed by a microfluidizer (Microfluidizer M-110S-E, manufactured by Microfluidex International Corporation).
The pressure in the H and G10Z interaction chambers) was adjusted to 1750 kg / cm ² , and the treatment was performed 3 times to obtain a silver behenate dispersion A. At this time, a desired heat dispersal temperature was set by mounting a spiral tube heat exchanger before and after the interaction chamber and adjusting the temperature of the refrigerant. The silver behenate particles contained in the obtained silver behenate dispersion A had a volume weighted average diameter of 0.52 μm and a coefficient of variation of 15
% Particles. Particle size is measured by Malvern Instr
It was performed with MasterSizer X manufactured by uments Ltd. When evaluated by electron micrograph, the ratio of long side to short side is 1.
5, the grain thickness was 0.14 μm, and the average aspect ratio (ratio between the equivalent circle diameter of the projected area of the grain and the grain thickness) was 5.1. The obtained silver behenate dispersion A was used for the preparation of the coating liquid described below.

<< Preparation of Solid Fine Particle Dispersion of Reducing Agent >> Reducing agent [1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane] 10k
400 g of Surfynol 104E (manufactured by Nissin Chemical Co., Ltd.), 640 g of methanol, and 16 kg of water were added to 10 kg of a 20 mass% aqueous solution of g and denatured polyvinyl alcohol (Kuraray Co., Ltd., Poval MP203) and mixed well. Into a slurry. This slurry was sent by a diaphragm pump and filled with zirconia beads having an average diameter of 0.5 mm (manufactured by Aimex Co., U
After dispersing for 3 hours and 30 minutes with VM-2), 4 g of benzoisothiazolinone sodium salt and water are added to adjust the concentration of the reducing agent to 25% by mass, and a solid fine particle dispersion of the reducing agent is obtained. It was The reducing agent particles contained in the obtained dispersion have a median diameter of 0.44 μm and a maximum particle diameter of 2.0 μ.
The average particle size variation coefficient was 19% or less. The obtained dispersion is filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust,
It was used for the preparation of the following coating liquid.

<< Preparation of Solid Fine Particle Dispersion of Organic Polyhalogen Compound A >> 10 kg of organic polyhalogen compound A [tribromomethyl (4- (2,4,6-trimethylphenylsulfonyl) phenyl) sulfone], modified polyvinyl alcohol ( Kuraray Co., Ltd., Poval MP203) 20% by mass aqueous solution 10 kg, sodium triisopropylnaphthalenesulfonate 20% by mass aqueous solution 639 g,
Surfynol 104E (Nissin Chemical Co., Ltd.) 400
g, 640 g of methanol and 16 kg of water are added,
Mix well to form a slurry. A horizontal bead mill (IMEX Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm by sending this slurry with a diaphragm pump.
Manufactured by UVM-2) and dispersed for 5 hours, and then water was added to adjust the concentration of the organic polyhalogen compound A to 25% by mass to obtain a solid fine particle dispersion of the organic polyhalogen compound A. The organic polyhalogen compound particles contained in the obtained dispersion had a median diameter of 0.36 μm, a maximum particle diameter of 2.0 μm or less, and an average particle diameter variation coefficient of 18%. The obtained dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, and then used for the preparation of the following coating solution.

<< Preparation of Solid Fine Particle Dispersion of Organic Polyhalogen Compound B >> 5 kg of organic polyhalogen compound B [tribromomethylnaphthyl sulfone], modified polyvinyl alcohol (Kuraray Co., Ltd., Poval MP203) 20
A 2.5% by weight aqueous solution, 213 g of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate and 10 kg of water were added and mixed well to obtain a slurry. This slurry was sent by a diaphragm pump and dispersed for 5 hours in a horizontal bead mill (UVM-2, manufactured by Aimex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm, and then benzoisothiazolinone sodium salt 2. 5 g and water were added to adjust the concentration of the organic polyhalogen compound B to be 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 obtained dispersion had a median diameter of 0.38 μm, a maximum particle diameter of 2.0 μm or less, and a coefficient of variation of average particle diameter of 20%. The resulting dispersion is
After filtering with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, it was used for the preparation of the following coating solution.

<< Preparation of Organic Polyhalogen Compound C Aqueous Solution >> While stirring at room temperature, 75.0 ml of water and sodium tripropylnaphthalenesulfonate (20% aqueous solution)
8.6 ml, sodium dihydrogen orthophosphate dihydrate (5% aqueous solution) 6.8 ml, potassium hydroxide (1 mol
/ L aqueous solution) was sequentially added, and the mixture was stirred and mixed for 5 minutes after the addition was completed. Further, 4.0 g of a powder of the organic polyhalogen compound C [3-tribromomethanesulfonylbenzoylaminoacetic acid] was added with stirring and uniformly dissolved to obtain 100 g of a transparent solution. The resulting aqueous solution is 20
After filtering with a 0 mesh polyester screen to remove foreign matters such as dust, it was used for the preparation of the following coating liquid.

<< Preparation of Emulsified Dispersion of Compound Z >> Compound Z
1 of R-054 (manufactured by Sanko Co., Ltd.) containing 85% by mass of
After mixing 0 kg and 11.66 kg of MIBK, the atmosphere was replaced with nitrogen and the mixture was dissolved at 80 ° C. for 1 hour. Add 25.5 water to this liquid.
2 kg, modified polyvinyl alcohol (manufactured by Kuraray Co., Ltd.,
20-40% by weight of a 20% by weight aqueous solution of MP-203) and 0.44 kg of a 20% by weight aqueous solution of sodium triisopropylnaphthalenesulfonate are added to the mixture to give 20-40%.
It was emulsified and dispersed at 3600 rpm at 60 ° C. for 60 minutes. Furthermore, Surfynol 104E (Nisshin Chemical Co., Ltd.)
0.08 kg of water and 47.94 kg of water were added and distilled under reduced pressure to remove MIBK, and then the concentration of the compound Z was adjusted to 10% by mass. The particles of compound Z contained in the thus obtained dispersion have a median diameter of 0.19 μm, a maximum particle diameter of 1.5 μm or less, and a coefficient of variation of particle diameter of 17%.
Met. The obtained dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, and then used for the preparation of the following coating solution.

[0162]

[Chemical 2]

<< Preparation of 6-Isopropylphthalazine Compound Dispersion >> Denatured polyvinyl alcohol (Kuraray Co., Ltd., Poval MP) while stirring 62.35 g of water at room temperature.
203) 2.0 g was added so as not to form a lump, and mixed by stirring for 10 minutes. After that, the mixture was heated to raise the internal temperature to 50 ° C., and then stirred at an internal temperature of 50 to 60 ° C. for 90 minutes to uniformly dissolve it. The inner temperature was lowered to 40 ° C. or lower, and polyvinyl alcohol (Kuraray Co., Ltd., PVA-21
7, 10 mass% aqueous solution) 25.5 g, sodium tripropylnaphthalene sulfonate (20 mass% aqueous solution) 3.
0 g and 7.15 g of 6-isopropylphthalazine (70% by mass aqueous solution) were added, and the mixture was stirred for 30 minutes and the transparent dispersion liquid 10 was added.
0 g was obtained. The obtained dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, and then used for the preparation of the following coating solution.

<< Preparation of Solid Fine Particle Dispersion of Hardening Agent X >>
1 kg of polyvinyl alcohol (Poval PVA-217 manufactured by Kuraray Co., Ltd.) against 4 kg of the contrast enhancing agent X
And 36 kg of water were added and mixed well to form a slurry. This slurry was sent by a diaphragm pump, and a horizontal bead mill (UVM-2, manufactured by Aimex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm was used.
After time-dispersion, 4 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the contrast-improving agent to 10% by mass, and a solid fine particle dispersion of the contrast-increasing agent was obtained. The particles of the contrast-increasing agent contained in the thus obtained dispersion had a median diameter of 0.34 μm, a maximum particle diameter of 3.0 μm or less, and a coefficient of variation of particle diameter of 19%. The obtained dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, and then used for the preparation of the following coating solution.

<< Preparation of Solid Fine Particle Dispersion of Development Accelerator W >> 10 kg of the development accelerator W, 10 kg of a 20% by mass aqueous solution of modified polyvinyl alcohol (POVAL MP203 manufactured by Kuraray Co., Ltd.) and 20 kg of water were added, Mix well to form a slurry. This slurry was sent by a diaphragm pump and filled with zirconia beads having an average diameter of 0.5 mm (manufactured by Aimex Co., U
After being dispersed in VM-2) for 5 hours, water was added to adjust the concentration of the development accelerator W to 20% by mass to obtain a solid fine particle dispersion of the development accelerator W. The development accelerator particles contained in the thus obtained dispersion have a median diameter of 0.5 μm.
m, the maximum particle diameter was 2.0 μm or less, and the variation coefficient of the average particle diameter was 18%. The resulting dispersion has a pore size of 3.0μ
After being filtered with a polypropylene filter of m to remove foreign matters such as dust, it was used for the preparation of the following coating liquid.

<< Preparation of Solid Fine Particle Dispersion of Organic Polyhalogen Compound D >> 6 kg of the organic polyhalogen compound D and modified polyvinyl alcohol (POVAL M manufactured by Kuraray Co., Ltd.)
P203) 10% by weight aqueous solution 12 kg, sodium triisopropylnaphthalene sulfonate 20% by weight aqueous solution 240 g, and water 0.18 kg were added and mixed well to form a slurry. This slurry was sent by a diaphragm pump, and a horizontal bead mill (made by Aimex Co., Ltd., UV) filled with zirconia beads having an average diameter of 0.5 mm was used.
After being dispersed in M-2) for 5 hours, 2 g of benzoisothiazolinone sodium salt and water were added to adjust the concentration of the organic polyhalogen compound D to 30% by mass. A fine particle dispersion was obtained. Organic polyhalogen compound particles contained in the obtained dispersion,
The median diameter was 0.40 μm, the maximum particle diameter was 2.0 μm or less, and the variation coefficient of the average particle diameter was 20%. The obtained dispersion was filtered through a polypropylene filter having a pore size of 3.0 μm to remove foreign matters such as dust, and then used in the preparation of the coating liquid described below.

[0167]

[Chemical 3]

<< Preparation of Coating Solution for Image Forming Layer >> To 1 mol of silver of silver behenate dispersion A, the following binder, materials and silver halide emulsion A were added, and water was added to form an image forming layer. It was used as a coating liquid. After completion, vacuum degassing was performed for 45 minutes at a pressure of 0.54 atm. The pH of the coating solution is 7.
The viscosity was 3 to 7.7 and the viscosity was 40 to 50 mPa · s at 25 ° C. Binder: SBR latex (St / Bu / AA = 68/29/3 (mass%), glass transition temperature: 17 ° C. (calculated value), using Na ₂ S ₂ O ₈ as a polymerization initiator, pH: NaOH Adjusted to 6.5, average particle size: 118 nm) 397 g as solid content 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane solid content 118.2 g Organic polyhalogen compound A as solid content 20.0 g Organic polyhalogen compound B as solid content 6.0 g Organic polyhalogen compound C as solid content 2.0 g Organic polyhalogen compound D as solid content 34.4 g Development accelerator W solid content 11.5 g sodium ethylthiosulfonate 0.3 g benzotriazole 1.2 g polyvinyl alcohol (Kuraray Co., Ltd., PVA-235) 10.8 g 6-isopropylphthalazine 14.0 g Compound Z As solid content 9.6 g Compound C 0.2 g Contrast agent X 8.9 g Dye A (low molecular weight of average molecular weight 15,000) Addition as a mixed solution with gelatin) Coating amount at which the optical density at 783 nm becomes 0.3 (solid content 0.40 g as a standard) Silver halide emulsion A 0.06 mol as Ag amount Compound A as preservative 40 ppm in coating liquid (2.5 mg / m ² as coating amount) 1% by mass as the total amount of solvent in the coating liquid of methanol 2% by mass as the total amount of solvent in the coating liquid of ethanol NaOH was used as the pH adjuster.

<< Preparation of Coating Solution for Lower Layer of Protective Layer >> n-butyl acrylate / methyl methacrylate = 42/58 (mass% ratio, I / O value = 0.52, Tg = 30 ° C .: DSC measurement value, MFT = 22 Water was added to 900 g of a polymer latex solution (having a solid content concentration of 28.0% and containing 100 ppm of compound A) having an average particle size of 150 nm and a mass average molecular weight of 800,000, and 0.2 g of compound E and polyvinyl alcohol ( Kuraray Co., Ltd. product, PVA-235) was added as solid content of 30 g, and water was further added to obtain 2.35.
L coating liquid (containing 0.5% by mass of a methanol solvent) was prepared. After completion, vacuum degassing is performed at a pressure of 0.47 atm 60
I went for a minute. The coating solution has a pH of 5.2 and a viscosity of 3 at 25 ° C.
It was 5 mPa · s.

<< Preparation of Coating Solution for Upper Layer of Protective Layer >> The polymer latex solution shown in Table 1 (as solid content concentration 28.0)
%, Compound A 100 ppm, containing the film-forming auxiliary in the amount shown in Table 1) 900 g, as a slipping agent, carnava wax (Chukyo Yushi Co., Ltd., Cerosol 524: less than 5 ppm as silicone content) 30 mass % Solution was added as described in Table 1, and further 0.3 g of compound C, 2.5 g of compound E, 35 g of compound F, 6 g of compound H, matting agent (polystyrene particles, average particle size 7 μm, average 10 g of variation coefficient of particle size) and 35 g of polyvinyl alcohol (PVA-235, manufactured by Kuraray Co., Ltd.) were added, and water was further added to apply 2.65 L of coating liquid (containing 1.5% by mass of methanol solvent). Was prepared. After completion, vacuum degassing was performed for 60 minutes at a pressure of 0.47 atm. The coating solution had a pH of 2.2 and a viscosity of 38 mPa · s at 25 ° C.

[0171]

[Chemical 4]

<< Preparation of polyethylene terephthalate (PET) support with back / undercoat layer >> (1) Preparation of PET support Using terephthalic acid and ethylene glycol, an 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, melted at 300 ° C and
After extruding from the die, it is cooled rapidly 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, transverse stretching was carried out 4.5 times with a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After that, after heat setting at 240 ° C. for 20 seconds, 4% relaxation was carried out in the lateral direction at the same temperature. After this, after slitting the chuck part of the tenter, both ends are knurled and 4.8k
It was wound up at g / cm ² . Thus, the width 2.4
m, length 3500 m, thickness 120 μm PE roll
A T support was obtained.

(2) Preparation of undercoat layer and back layer Undercoat first layer A coating solution having the composition shown below was coated on a support at a rate of 6.2 ml / m ^2, and the temperature was 125 ° C. for 30 seconds and 150 ° C. 30
Second, dried at 185 ° C. for 30 seconds. [Coating Liquid] Latex-A 280 g KOH 0.5 g Polystyrene fine particles (average particle size: 2 μm, coefficient of variation of average particle size 7%) 0.03 g 2,4-dichloro-6-hydroxy-s-triazine 1.8 g Distillation Amount of water totaling 1000g

Undercoating second layer A coating solution having the composition shown below was applied on the undercoating first layer so as to have a concentration of 5.5 ml / m ^2, and the mixture was heated at 125 ° C. for 30 seconds for 150 seconds.
It was dried at 30 ° C. for 30 seconds and at 170 ° C. for 30 seconds. [Coating liquid] Deionized gelatin (Ca ²⁺ content 0.6 ppm, jelly strength 230 g) 10 g Acetic acid (20% aqueous solution) 10 g Compound-Bc-A 0.04 g Methylcellulose (2% aqueous solution) 25 g Emalex 710 (Japan emulsion) (Manufactured by Co., Ltd.) 0.3 g distilled water Total amount of 1000 g

Back first layer 0.375 kV · on the surface opposite to the surface coated with the undercoat layer.
A · min / m ² corona discharge treatment was applied, and a coating solution having the composition shown below was applied to the surface so as to be 13.8 ml / m ^2, and the temperature was 125 ° C. for 30 seconds and 150 ° C. for 30 seconds. It was dried at 30 ° C. for 30 seconds. [Coating Liquid] Pethresin A520 (30% aqueous dispersion, manufactured by Takamatsu Yushi Co., Ltd.) 46 g Alkali-treated gelatin (molecular weight about 10,000, Ca ²⁺ content 30 ppm) 4.44 g Deionized gelatin (Ca ²⁺ content 0.6 ppm) ) 0.84 g Compound-Bc-A 0.02 g Dye-Bc-A (adjusted so as to have an optical density of 783 nm of 1.3 to 1.4) 0.88 g Polyoxyethylene phenyl ether 1.7 g Water-soluble Melamine compound (Sumitomo Chemical Co., Ltd., Sumitex Resin M-3, 8% aqueous solution) 15 g Sb-doped SnO ₂ acicular particle water dispersion (Ishihara Sangyo Co., Ltd., FS-10D) 24 g Polystyrene Fine particles (average particle size 2 μm, coefficient of variation of average particle size 7%) 0.03 g Distilled water Total amount is 1000 g

Back second layer A coating solution having the composition shown below was applied onto the back first layer so that the coating solution had a concentration of 9.7 ml / m ^2, and the temperature was set at 125 ° C. for 30 seconds for 150 seconds.
It was dried at 30 ° C. for 30 seconds and at 170 ° C. for 30 seconds. [Coating Liquid] 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 Distillation Amount of water totaling 1000g

Back third layer 12.5 ml / m of a coating solution having the composition described above and below.
Apply it to the second layer of the back so that it becomes ^2, and apply 3 at 125 ° C.
It was dried for 0 seconds, 150 ° C. for 30 seconds, and 170 ° C. for 30 seconds. [Coating liquid] Deionized gelatin (Ca ²⁺ content 0.6 ppm, jelly strength 230 g) 10 g Acetic acid (20% aqueous solution) 10 g Compound-Bc-A 0.04 g Methylcellulose (2% aqueous solution) 25 g Emalex 710 (Japan emulsion) 0.3 g potassium chloride 1.0 g potassium bromide 1.0 g distilled water Total amount of 1000 g

Back fourth layer A coating solution having the composition shown below was applied onto the back third layer so as to have a concentration of 13.8 ml / m ^2, and the mixture was heated at 125 ° C. for 30 seconds for 150 seconds.
It was dried at 30 ° C. for 30 seconds and at 170 ° C. for 30 seconds. [Coating liquid] Julimer ET410 (30% water dispersion, manufactured by Nippon Pure Chemical Industries, Ltd.) 23 g Chemipearl S120 (27% water dispersion, manufactured by Mitsui Petrochemical Co., Ltd.) 135 g Alkali-treated gelatin (molecular weight about 10,000, Ca ^{2 +} Content 30 ppm) 12.7 g Compound-Bc-D 0.25 g Cerosol 524 (30% aqueous solution, manufactured by Chukyo Yushi Co., Ltd.) 12 g Water-soluble epoxy compound (Denacol EX521 manufactured by Nagase Kasei Co., Ltd.) 1.8 g Poly Methyl methacrylate particles (10% water dispersion, average particle size 5 μm, coefficient of variation of average particles 7%) 7.7 g Distilled water Total amount is 1000 g

[0179]

[Chemical 5]

Latex-A: core-shell type latex having a core portion of 90% by weight and a shell portion of 10% by weight (weight average molecular weight 38000) 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 (mass%)

(3) Heat Treatment for Transporting (3-1) Heat Treatment PE thus prepared and having a back / undercoat layer
The T support was put in a heat treatment zone having a total length of 200 m and set at 160 ° C., and was conveyed at a tension of 2 kg / cm ² and a conveying speed of 20 m / min. (3-2) Post-heat treatment Subsequent to the above heat treatment, it was passed through a zone at 40 ° C for 15 seconds to perform post-heat treatment and wound. The winding tension at this time was 10 kg / cm ² .

<Preparation of heat-developable image recording material> As described above, a back layer and an undercoat layer were applied, and heat-treated under transport to form an undercoat layer on a PET support.
No. 64 gazette, the slide bead coating method disclosed in FIG.
5 g / m so as to be ^2, on which the solid content coating amount of the polymer latex protective layer underlying coating solution is 1.0 g / m ²
In addition, the above-mentioned coating solution for the upper layer of the protective layer was further applied onto the image forming layer, the lower layer of the protective layer and the upper layer of the protective layer in such a manner that the solid coating amount of the polymer latex was 1.3 g / m ^2.
The layers were simultaneously multilayer coated.

The drying conditions at the time of application are as follows: the first drying zone (low speed air drying area) has a dry-bulb temperature of 70 to 75 ° C. and a dew point of 9 to 23.
C., the air velocity on the support surface is 8 to 10 m / s, and the liquid film surface temperature is 35 to 40.degree. C., and the second drying zone (high speed air drying region) has a dry bulb temperature of 65 to 70.degree. C. and a dew point of 20. ~ 23
And the wind speed on the support surface was 20 to 25 m / s. The residence time in the first drying zone was ⅔ of the constant rate drying period in this zone, and it was transferred to the second drying zone and dried. The first drying zone is a horizontal drying zone (support has an angle of 1.5 ° to 3 ° with respect to the horizontal direction of the coating machine).
Is. The coating speed was 60 m / min. Winding after drying was performed under the conditions of a temperature of 23 ± 3 ° C. and a relative humidity of 45 ± 5%. The winding shape was adjusted to the subsequent processing form (outer winding of the image forming layer side), and the image forming layer side was outside. In addition,
The relative humidity of the heat-developable image recording material is 20-40%.
The pH of the film surface on the image forming side of the obtained heat-developable image recording material was 5.0 (measured at 25 ° C.), and the film surface pH on the opposite side was 5.9.
Met. Then, a package of the roll-shaped heat-developable image recording material was prepared according to the following conditions under the environmental conditions of 23 ° C. ± 3 ° C. and relative humidity of 63 ± 5%.

<< Production of Light-Shielding Leader >> A light-shielding film (a low-density polyethylene sheet having a thickness of 30 μm containing 5% by mass of carbon black) is provided on both sides of a shrink film having a thickness of 30 μm (TNS, manufactured by Gunze Co., Ltd.). The pieces were laminated to produce a heat-shrinkable light-shielding film strip. The heat shrinkage rate of the obtained heat-shrinkable light-shielding film strip is 10
At 0 ° C., 13.3% in the length direction and 11. in the width direction.
9%, and the Elmendorf tear load in the longitudinal direction was 0.
It was 43N. This heat-shrinkable light-shielding film strip,
A light-shielding sheet made by laminating a low-density polyethylene sheet having a thickness of 40 μm in which 5% by mass of carbon black is mixed on both side surfaces of a PET sheet having a thickness of 100 μm, along both side edges so as to protrude in the width direction. Then, they were attached to each other to manufacture a light-shielding reader.

<< Production of Light-Shielding Heat-Developable Image-Recording Material Roll >> The above-mentioned heat-developable image-recording material is cut out into a width of 610 mm and a winding length of 59 m with the light-shielding leader being the outside with the surface having the image forming layer on the outside. It was wrapped around a paper core having a diameter of 3 inches. Then, disc-shaped light-shielding members were attached to both ends of the heat-developable image recording material roll. Then, a light-shielding leader is attached to the roll-shaped heat-developable image recording material with an adhesive tape, and while being wrapped around the heat-developable image-recording material roll, hot air at 270 ° C. is applied to the surface of the heat-shrinkable light-shielding film strip of the light-shielding leader. The thin pieces of heat-shrinkable light-shielding film of the light-shielding leader were sprayed onto the outer surface of the disc-shaped light-shielding member to contact the outer surface in a heat-shrinkable state. Then, the end of the light-shielding leader at the end of winding and the outer surface of the light-shielding leader before one revolution is sealed with an adhesive tape, and then a thin film of a heat-shrinkable light-shielding film that is in close contact with the outer surface of the disc-shaped light-shielding member. A heater heated to 130 ° C. was pressed against the surface of the piece to fuse the outer surface of the disk-shaped light-shielding member and the heat-shrinkable light-shielding film strip.

<< Measurement and Evaluation >> The roll-shaped heat-developable image recording material obtained above was measured and evaluated according to the following method. Vickers hardness: Determined by the Vickers hardness test method described in JIS Z2244, B7725. The specific measuring method is as described above, and it was determined by the above formula (2).

The dynamic friction coefficient sample was allowed to stand for 30 minutes at 25 ° C. and a relative humidity of 55 ± 5%, and then a surface property measuring instrument (manufactured by Shinto Scientific Co., Ltd., HEIDO
N Tribogear TYPE: 14DR), 60 ℃
The heat-developable image recording material was placed on the smooth surface of the stainless steel plate (SUS32), and a load of 100 g was applied, the smooth surface of the stainless steel plate was slid at a speed of 20 mm / sec, and the dynamic friction resistance at that time was measured. The dynamic friction coefficient was calculated from the equation (1).

Transportability (Scratches / Jamming) As an automatic transport system from exposure to heat development, the following image forming apparatuses of A1 size and A2 size are used to perform image forming processing under standard processing conditions to prevent scratches and the like. The occurrence of surface defects and jamming were evaluated. (1) A1 size exposure apparatus: NEC Corporation FT-296R, Conveyor: Fuji Photo Film Co., Ltd., Dry System Auto Carrier FDS-C1100 Thermal development processor: Fuji Photo Film Co., Ltd., Dry System Processor FDS-6100X (2) A2 size exposure device: NEC Corporation, FT-286R Conveyor: Fuji Photo Film Co., Ltd., Dry System Auto Carrier FDS-C1000 Thermal processor: Fuji Photo Film Co., Ltd. ), Dry System Processor FDS-6100X

The results obtained are shown in Table 1. From the results of Table 1, sample Nos. 1 to 14 satisfying the conditions of the present invention have no jamming during the processing from exposure to heat development in the image forming processing system apparatus of automatic conveyance, and the surface of the heat development image recording material is not generated. It can be seen that there is no shape defect and the transportability is excellent. In addition, sample numbers 1 to 14 satisfying the conditions of the present invention
Has a high Dmax (maximum density) and has a high contrast (γ ≧
10) and the fog was low.

[0190]

[Table 1]

[0191]

INDUSTRIAL APPLICABILITY The heat-developable image recording material of the present invention is excellent in heat-development processing suitability since it does not cause surface defects such as scratches or obstacles such as jamming when exposed to heat and developed by an automatic transport system. , Dmax (maximum density) is high, the contrast is high (γ ≧ 10) and the fog is low, and it is possible to obtain an image most suitable for photoengraving. Therefore, the photothermographic material of the invention is suitable for photolithography. Further, the heat-developable image recording material of the present invention can be prepared by water-based coating which is advantageous in terms of environment and cost.

Continued front page    F term (reference) 2H112 AA03 BA00 BC22 BC24                 2H123 AB00 AB03 AB23 AB28 BA00                       BA14 BA47 BA48 BA49 BB00                       BB15 BB17 BB20 BB31 CB00                       CB03 CB20

Claims (8)

[Claims] 1. A heat-developable image recording material having at least one image forming layer on a support and at least one protective layer provided on the image forming layer, the surface having the image forming layer. A heat-developable image recording material, which has a coefficient of dynamic friction with a smooth surface of a stainless steel plate at 60 ° C. of 0.7 or less. 2. The glass transition temperature of the outermost protective layer is 40.
The heat-developable image recording material according to claim 1, which has a temperature of not less than ° C. 3. The dynamic friction coefficient between the surface on the side opposite to the side having the image forming layer and the smooth surface of a stainless steel plate at 60 ° C. is 0.3 or less. Thermal development image recording material. 4. The heat-developable image according to claim 1, wherein the outermost layer on the side having the image forming layer and / or the side opposite thereto contains a lubricant and a matting agent. Recording material. 5. A polymer latex is used as a binder for the protective layer, and the minimum film-forming temperature of the polymer latex is not higher than the glass transition temperature of the protective layer. The heat-developable image recording material as described in 1 above. 6. The heat-developable image recording material comprises an image-forming layer containing an organic silver salt, a photosensitive silver halide and a reducing agent and a back layer on a support, and the support is heat-treated. Any one of claims 1 to 5 characterized in that
The heat-developable image recording material according to the item. 7. The heat-developable image recording material contains a high contrast agent.
The heat-developable image recording material according to the item. 8. An exposure device for exposing a heat-developable image recording material, a heat developing device equipped with a preheating part, a heat developing part, a slow cooling part and a deodorizing device, and an exposure device connected to the heat developing device. Forming an image of the heat-developable image recording material according to any one of claims 1 to 7 by using an automatic conveying system device comprising an auto carrier for automatically conveying the heat-developable image recording material from the heat developing machine to the heat developing machine. And an image forming method.