JP2003315958A - Heat-developable material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-developable material which prevents falling of a matting agent in a process of producing the heat-developable material or during conveyance on rollers in a heat developing machine and repairs image defects caused by a fallen material. <P>SOLUTION: In the heat-developable material comprising on a support at least photosensitive silver halide grains, an organic silver salt, a reducing agent and a binder, fine particles having a silsesquioxane structure surface-substituted by fluorine atoms are comprised. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-developable material for forming an image by post-exposure heat development, and more specifically, a heat-development for forming an image by post-exposure heat development with improved transportability in a production process or a developing processor. It is about materials.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of environmental protection and workability in the medical field, there has been a strong demand for a photographic material capable of forming an image by light or heat treatment which does not generate waste liquid associated with a wet process, and particularly, both of light and heat are required. A technique relating to a photothermographic material capable of forming a clear black image with high resolution by utilizing development has been commercialized and rapidly spread. Since these photothermographic materials are usually developed at a temperature of 80 ° C. or higher, they are called thermal development materials in distinction from conventional wet photosensitive materials which are liquid-developed in the range of 25 ° C. to 45 ° C.

Conventionally, this type of heat-developable material contains a reducing agent and an organic silver salt as essential components in addition to the photosensitive silver halide, so that a large amount of photographic additives are contained in the photosensitive layer. The role of the binder to hold becomes important. However, since only one photosensitive layer cannot sufficiently prevent adhesion of stains and scratches due to rubbing due to handling at the time of photographing and reading after being shipped as a product or as a product, at least one layer is provided on the photosensitive layer. A protective layer is provided. The protective layer not only prevents scratches due to abrasion during transportation of the heat developing material in the production process or developing processor, but also prevents friction or peeling electrification due to transportation, and the heat developing material is cut into a certain size to form a plurality of sheets. It has the role of preventing sticking when stacked and wrapped. Therefore, inorganic or organic fine particles for making the surface uneven, a so-called matting agent, an antistatic agent for preventing the accumulation of static electricity, a lubricant for controlling the friction coefficient and the like are added. However, since the conventional matting agent is present as protrusions on the surface, peeling or peeling occurs during high-speed transportation during the production process or development processing of the heat developing material, and the contamination of the peeled material may occur on the surface of the heat developing material. Causes image defects. Even if it does not adhere to the surface, if the transport roller is contaminated, the flatness of the roller is impaired, causing uneven coating and poor transport. To prevent this, it is better to use contactless conveyance for coating drying and cutting, but it is too costly to contactlessly perform all the steps, so some of them must be brought into contact with rollers. The method of transportation is adopted. Therefore, there has been a demand for a matting agent that does not peel or peel off or a method of using a matting agent.

The stripping of the matting agent causes stress during transportation because the fine particles to be used are organic or inorganic fine particles which are hard to be fixed to the binder and stick out to the surface of the heat developing material. A crack is formed in the part and causes peeling. Therefore, it has been attempted to use a functional group existing on the surface of the matting agent to bind to and immobilize it on the binder through a crosslinking agent in order to immobilize it on the binder.
However, when a reactive group is introduced, cross-linking occurs between matting agents, which causes a problem of easy aggregation. In addition, since the matting agent is peeled off due to the frictional force with the transport roller, a method of adding a lubricant has been proposed, but the lubricant easily transfers to the roller and causes a lubricant stain, which may impair the uniformity of application. There was a drawback that

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a matting agent during the process of producing a heat-developable material or during transportation on a roller in a heat-development processor. It is an object of the present invention to provide a heat-developable material capable of preventing peeling and improving image defects caused by the peeling substance.

[0006]

The above object of the present invention can be achieved by the following constitutions.

1. A heat-developable material containing at least a photosensitive silver halide grain, an organic silver salt, a reducing agent and a binder on a support, and containing fine particles having a silsesquioxane structure whose surface is substituted with a fluorine atom. A heat developing material characterized by:

2. 2. The heat-developable material as described in 1 above, wherein the fine particles having a silsesquioxane structure have an average particle diameter of 0.7 nm to 10 μm.

3. 3. The heat-developable material as described in 1 or 2 above, wherein the fine particles having the silsesquioxane structure are contained in the outermost layer or the undercoat layer.

4. 4. The heat-developable material according to any one of 1 to 3, wherein the fine particles having a silsesquioxane structure are covalently bonded to the binder.

5. The fine particles having the silsesquioxane structure are covalently bonded to the binder via a crosslinking agent having an isocyanate group, a vinylsulfonyl group, an epoxy group or an alkoxysilane group, and are immobilized. The heat-developable material as described in 4 above.

6. 6. The heat according to any one of 1 to 5 above, wherein the layer containing the fine particles having the silsesquioxane structure contains a surfactant having an organic group having a fluorine atom in the molecule. Development material.

The present invention will be described in detail below. The heat developable material of the present invention is a heat developable material containing at least a photosensitive silver halide grain, an organic silver salt, a reducing agent and a binder on a support, and a silsesquioxane having a surface substituted with a fluorine atom. It is characterized by containing fine particles having a structure. The heat-developable material of the present invention comprises at least four undercoat layers on a support, a photosensitive layer containing silver halide grains, and a photosensitive layer protective layer adjacent to the photosensitive layer. It is preferable that at least one of the undercoat layers or the photosensitive layer protective layer or the backing layer protective layer contains fine particles having a silsesquioxane structure whose surface is substituted with a fluorine atom.

The light-sensitive layer of the heat-developable material contains light-sensitive silver halide grains which may be sensitized with a spectral sensitizing dye, and the light-sensitive layer or its adjacent layer further contains an organic material serving as a silver source. A silver salt and a reducing agent for developing the silver salt to form a silver image are contained.

Hereinafter, fine particles having a silsesquioxane structure in which the surface used for the undercoat layer or the protective layer for the photosensitive layer of the heat-developable material of the present invention is substituted with a fluorine atom, a photosensitive silver halide grain, and an organic silver. The salt, reducing agent, binder, crosslinking agent and the like will be described in detail.

The fine particles having a silsesquioxane structure whose surface is substituted with a fluorine atom according to the present invention are a method in which fluorinated organotrichlorosilane is added to a saturated aqueous solution of hydrogen chloride to cause hydrolysis and condensation reaction; Method of adding trialkoxysilane to an acidic or alkaline aqueous solution containing an ionic surfactant to cause hydrolysis and condensation reaction; Fluorinated organotrialkoxysilane and / or its partially hydrolyzed condensate are nonionic surfactants and cations Of emulsifying and dispersing in water in the presence of a water-soluble surfactant, and adding an alkali for hydrolysis and condensation reaction; a method of neutralizing and condensing a fluorinated organosilanol alkali metal salt with an acid in an aqueous solution; fluorinated organo Interfacial activation of trialkoxysilane and / or its partial hydrolysis-condensation product Method of gradually dropping into aqueous solution containing agent to cause hydrolysis and condensation reaction; hydrolysis and condensation after suspension in dispersion medium in the presence of basic catalyst or acidic catalyst using nonionic surfactant as dispersant Method of reacting;
A method in which a fluorinated organopolysiloxane is dissolved in an aqueous solution of an alkali hydroxide, cations are removed by an ion exchange method, and the resulting solution is subjected to a condensation reaction at 50 ° C. or higher and pH 10 or higher (JP-A-6-279589). ); Add organotrialkoxysilane to an aqueous solution of alkali metal hydroxide, ammonia or amine with stirring,
Method of hydrolysis and condensation reaction (Japanese Patent Publication No. 40-1691)
No. 7); organotrialkoxysilane and / or its partial hydrolysis-condensation product is added to an aqueous solution of an alkaline earth metal hydroxide or an alkali metal carbonate for hydrolysis,
Condensation reaction method (Japanese Patent Publication No. 56-39808): Organotrialkoxysilane or its partial hydrolyzed condensate is hydrolyzed and condensed in an aqueous solution of ammonia or amine, and heated at a temperature of 70 to 80 ° C. After promoting the condensation with and washing the product,
A method of pulverizing (Japanese Patent Publication No. 22767/1990); a method of dissolving organotrialkoxysilane in an organic carboxylic acid aqueous solution and then conducting a condensation reaction in an alkaline aqueous solution (Japanese Patent Laid-Open No. 3-244636); A method in which silane is dissolved in an organic solvent, then mixed with an acidic aqueous solution to be hydrolyzed, and then a base is added to cause a condensation reaction; a hydrolyzable organic metal compound is composed of a hydrolysis catalyst, water, an electrolyte and a solvent. Method of hydrolyzing and condensing in a solution; Method of hydrolyzing and condensing fluorinated organoalkoxysilane in the presence of an aqueous solution containing a nonionic surfactant and ammonia and / or amine; Anion of fluorinated organoalkoxysilane Hydrolyzing in an aqueous solution containing a surfactant and ammonia and / or amine Solution, it is possible to obtain a polyorganosilsesquioxane particles of suitable particle size by the method is a condensation reaction or the like. In order to obtain a larger particle size, for example, when methyltrimethoxysilane is used as a raw material, the average particle size can be adjusted by adjusting the amount of the catalyst (alkali), fluorinated organotrialkoxysilane and / Or a partial hydrolysis-condensation product thereof and an aqueous solution of ammonia or amine are stirred at a low speed, and a fluorinated organotrialkoxysilane and / or a partial hydrolysis-condensation product thereof is used as an upper layer to carry out hydrolysis and condensation reaction while maintaining a two-layer state. Method: Fluorinated organotrialkoxysilane and / or its partial hydrolysis-condensation product and water are stirred to form a uniform solution, and then alkali is added for hydrolysis and condensation reaction; To a water / alcohol solution, then add an alkaline aqueous solution, and then stand still And a method of condensing the. The particularly preferred fine particles having a silsesquioxane structure whose surface is substituted with a fluorine atom according to the present invention have the following three-dimensional structure as a minimum unit, and have eight R ^{1 to} R ⁸ substituents in any form. Can have The number of fluorinated organic groups on the outermost surface increases as the particle size increases.

[0017]

[Chemical 1]

In the formula, R ^{1 to} R ⁸ represent a substituent of the silsesquioxane mother nucleus, and examples thereof include a hydrogen atom, a halogen atom (eg, chlorine atom, fluorine atom, etc.), a chain or branched alkyl group. Group (for example, methyl group, ethyl group, propyl group, i-propyl group, butyl group, i-butyl group, cyclohexyl group, etc.), alkenyl group (propenyl group, butenyl group, octenyl group, etc.), alkoxy group (methoxy group) ,
Ethoxy group, butoxy group, etc.), hydroxyl group, amino group, aryl group (phenyl group, naphthyl group, etc.), heterocyclic group (pyridyl group, furyl group, thiophenyl group, etc.) and the like. At least one of the substituents R ^{1 to} R ⁸ is preferably an organic substituent J-1 to J-16 substituted with the following fluorine atom.

[0019]

[Chemical 2]

Further, if not substituted by a fluorine atom,
Examples of organic substituents that are reactive groups with the crosslinking agent are shown below.

[0021]

[Chemical 3]

Specific examples (combination examples) of the substituents R ^{1 to} R ⁸ of the silsesquioxane mother nucleus having the three-dimensional structure are shown below.

[0023]

[Chemical 4]

* Reactive group: Reactive group with crosslinker In the above, the substituents R ^{1 to} R ⁸ are M-8 and / or M-9.
In the case of, it is possible to polymerize by polymerization, and a molecular weight of 2000 to 10 is obtained by using an ordinary radical polymerization initiator.
It can be synthesized within the range of 0,000. Also, M-1 to
When it has at least one of the substituents such as M-7, it has a chemical organic bond (that is, the following) with a crosslinking agent having an isocyanate group, a vinylsulfonyl group, an epoxy group or the like.
Covalent bond). As the binder, those having an amino group, a hydroxyl group, a carboxyl group, an epoxy group or the like which react with these groups, which will be described later, are preferable.

The fine particles having a silsesquioxane structure whose surface is substituted with a fluorine atom according to the present invention include alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone and acetone, aromatic compounds such as toluene and xylene, and You may add it after melt | dissolving in an organic solvent, such as non-aromatic type | system | groups, such as normal hexane and decane, or fine particle dispersion. The amount in the protective layer of the undercoat layer or the photosensitive layer protection layer or the backing layer and a backing layer of, it is preferable that both the sum of one side of the amount of the support is ^{1mg / m 2 ~100g / m 2} . If it is less than this range, the effect of improving the transportability by the fine particles having a silsesquioxane structure in which the surface of the present invention is substituted with a fluorine atom cannot be obtained, and if it exceeds this range, haze, color tone, etc. are impaired. Absent.

The surfactant having an organic group having a fluorine atom in the molecule which is preferably used in the present invention is an organic group in which a part or all of an alkyl group and an alkenyl group which may be substituted are substituted with a fluorine atom. It is a surfactant having a hydrophobic portion, and the hydrophilic portion may be an anionic group, a cationic group or a nonionic group, but an anionic group is preferable. As the alkyl group, for example, a perfluorooctyl group, a perfluorononenyl group, a perfluorohexyl group and the like are preferable. As the anionic group, for example, a sulfonic acid group, a carboxylic acid group, a phosphoric acid group or their sodium salts, potassium salts, lithium salts and the like are preferable. The anionic group, which is a hydrophilic group, and the hydrophobic organic group containing a fluorine atom may be bonded via a divalent or trivalent linking group. Preferred examples of the divalent or trivalent linking group are a divalent group derived from an aromatic ring such as a benzene ring or a naphthalene ring; a monovalent acid residue such as succinic acid, itaconic acid or maleic acid; And a trivalent group derived from succinic acid, itaconic acid, maleic acid and the like. Preferred specific examples are shown below.

[0027]

[Chemical 5]

The addition amount of the above-mentioned surfactant having an organic group having a fluorine atom in the molecule is 1 μm per square meter.
The range of g to 10 g is preferable, and the range of 1 mg to 1 g is particularly preferable. If it is less than this range, it is difficult to obtain the effect of improving the transportability. Further, if it exceeds this range, the moisture resistance and the like deteriorate. The method for adding the above surfactant is to dissolve in alcohols such as methanol and ethanol, ketones such as methyl ethyl ketone and acetone, aromatic solvents such as toluene and xylene, and non-aromatic solvents such as normal hexane and decane. Alternatively, fine particles may be dispersed and added.

(Photosensitive silver halide grains) The photosensitive silver halide contained in the photosensitive layer of the heat-developable material of the present invention is
Preliminarily prepared by any method known in the field of photographic technology such as a single jet method or a double jet method, for example, an ammonia method emulsion, a neutral method, an acidic method or the like, and then added with other components of the present invention. It can be mixed and introduced into the composition used in the present invention. In this case, in order to sufficiently bring the photosensitive silver halide into contact with the organic silver salt,
For example, U.S. Pat. Nos. 3,706,564 and 3,7 have been used as protective polymers when preparing photosensitive silver halides.
No. 06,565, No. 3,713,833, No. 3,
748,143 and British Patent No. 1,362,970, means for using polymers other than gelatin such as polyvinyl acetals, and British Patent Nos. 1,3.
54,186 means for enzymatically decomposing gelatin in a light sensitive silver halide emulsion, or light sensitive silver halide grains as described in US Pat. No. 4,076,539. Each means such as a means for omitting the use of the protective polymer can be applied by preparing the compound in the presence of a surfactant.

The photosensitive silver halide preferably has a small grain size in order to suppress white turbidity after image formation and to obtain a good image quality. The average particle size is usually 0.1 μm or less, preferably 0.01 to 0.1 μm, and more preferably 0.02 to 0.08 μm. Further, the shape of silver halide is not particularly limited, and so-called normal crystal such as cubic or octahedron or non-normal crystal spherical, rod-shaped or tabular silver halide grains can be mentioned. The silver halide composition is also not particularly limited and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide and silver iodide.

The amount of the above-mentioned silver halide is usually 50% by mass or less, preferably 25 to 0.1% by mass, more preferably 15 to 0.1% with respect to the total amount of silver halide and the organic silver salt described below.
It is 1% by mass.

Further, a part of the organic silver salt can be converted into silver halide by using the above-mentioned silver halide composition component, and various conditions such as reaction temperature, reaction time, reaction pressure and the like in the process at that time. Can be appropriately set according to the purpose of production. Usually, it is preferable that the reaction temperature is −23 ° C. to 74 ° C., the reaction time is 0.1 second to 72 hours, and the reaction pressure is atmospheric pressure.

The photosensitive silver halide prepared by the above-mentioned various methods includes, for example, sulfur-containing compounds, gold compounds,
Platinum compound, palladium compound, silver compound, tin compound,
It can be chemically sensitized with a chromium compound or a combination thereof. Regarding the method and procedure of this chemical sensitization, for example, US Pat. No. 4,036,650, British Patent No. 1,518,850, and the like, JP-A-51-22430.
No. 51-78319, No. 51-81124 and the like.

The silver halide used in the present invention can be sensitized with a spectral sensitizing dye, if necessary. For example, JP-A Nos. 63-159841, 60-140335, 63-231437, 63. -259651, 6
3-304242, 63-15245, U.S. Pat. Nos. 4,639,414, 4,740,455,
No. 4,741,966, No. 4,751,175
Nos. 4,835,096 and the like can be used. The useful sensitizing dyes used in the present invention are, for example, JP-A Nos. 9-34078 and 9-54.
The compounds described in Nos. 409 and 9-80679 can be preferably used.

(Organic Silver Salt) The organic silver salt contained in the heat-developable material of the present invention is a reducible silver source, and silver of an organic acid, a heteroorganic acid and an acid polymer containing a reducible silver ion source. Salt or the like is used. Also, the ligand is 4.0-1
Organic or inorganic silver salt complexes having a total stability constant for silver ions of 0.0 are also useful. Examples of silver salts include silver salts of organic acids (eg, silver salts such as gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, and lauric acid).

(Reducing Agent) Examples of preferable reducing agents contained in the heat developing material of the present invention are described in US Pat. No. 3,770,44.
No. 8, No. 3,773, 512, No. 3, 593, 863
Although the compounds described in the above publications are applicable, specific examples of preferable reducing agents are shown below. (K-1) 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane (K-2) bis (2-hydroxy-3-t-butyl-5)
-Methylphenyl) methane (K-3) 2,2-bis (4-hydroxy-3-methylphenyl) propane (K-4) 4,4-ethylidene-bis (2-t-butyl-6-methylphenol) (K-5) 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane The compound shown above is used by being dispersed in water or dissolved in an organic solvent. As the organic solvent, alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, and aromatic solvents such as toluene and xylene can be arbitrarily selected and used. The amount of reducing agent used is
It is usually 1 × 10 ^-2 to 10 mol, preferably 1 per mol of silver.
× 10 ^{-2 to} 1.5 mol. When it is less than this range, the developability is deteriorated. Further, if it exceeds this range, fogging increases and storage stability deteriorates.

(Binder) As the polymer binder which is a binder used in the photosensitive layer or the non-photosensitive layer of the heat-developable material of the present invention, polyvinyl butyral, polyacrylamide, polystyrene, polyvinyl acetate, polyurethane, polyacryl is used. Examples thereof include acid esters, styrene-butadiene copolymers, acrylonitrile-butadiene copolymers, vinyl chloride-vinyl acetate copolymers, styrene-butadiene-acrylic copolymers. After further drying, after forming a film, it is preferable that the equilibrium water content of the coating film is low, as particularly low water content, for example, cellulose acetate of the organic solvent system, cellulose acetate butyrate and polyacetal. You can Polyacetal means a polymer obtained by producing polyvinyl alcohol by saponifying polyvinyl acetate and acetalizing the polyvinyl alcohol with an aldehyde compound, but as a preferred polyacetal in the present invention, acetalization with butyraldehyde is performed. Polybutyral and polyacetal acetalized with acetaldehyde (polyacetal in a narrow sense) are preferable. The acetalization degree theoretically exists up to 1 to 100%, but 20 to 95% is preferable for practical use. When the degree of acetalization is low, the number of hydroxyl groups increases, and the photographic performance becomes weak to humidity. In addition, when the degree of acetalization is high, the reaction temperature and time become excessive, and the cost and productivity deteriorate.

As the binder for water-based coating, a copolymer of styrene and butadiene which is a water-dispersed polymer, a copolymer of styrene and alkyl acrylate or alkyl methacrylate, and alkyl acrylate are used. Examples thereof include copolymers of methacrylic acid alkyl esters. The water-dispersible polymer is preferably fine particles having an average particle diameter of 1 nm to several μm and dispersed in an aqueous dispersion medium. Although the water-dispersed polymer is widely used as a binder for water-based coating, it is particularly preferable that it is hydrophobic from the viewpoint of improving water resistance. The degree of polymerization of the water-dispersed polymer can be freely selected from about 10 to about 10,000, but 100
˜6000 is preferable from the viewpoint of coating property and productivity in synthesis.

(Crosslinking Agent) The binder can maintain the adhesion to the lower layer and the upper layer and obtain a film strength that is less likely to be damaged by forming a film by itself. It is possible to improve film adhesion and film strength. Also,
The cross-linking agent that cross-links between the binders reacts with the organic or inorganic fine particles having a reactive group used in the present invention and chemically bonds (covalently bonds) with the binder to allow the fine particles to pass through the cross-linking agent. Immobilized on the binder. Preferred cross-linking agents used in the present invention include cross-linking agents having an isocyanate group, a vinylsulfonyl group, an epoxy group and an alkoxysilane group. Particularly preferred cross-linking agents include polyfunctional cross-linking agents having at least two isocyanate groups, vinylsulfonyl groups and epoxy groups in one molecule. Specific examples of preferred crosslinking agents used in the present invention are shown below.

[0040] (H-1) Hexamethylene diisocyanate (H-2) hexamethylene diisocyanate trimer (H-3) Tolylene diisocyanate (H-4) Phenylene diisocyanate (H-5) Xylylene diisocyanate

[0041]

[Chemical 6]

[0042]

[Chemical 7]

The above-mentioned cross-linking agent may be dissolved in water, alcohols, ketones or non-polar organic solvents and added,
You may add and use it as a solid in a coating liquid. The amount used is preferably equivalent to the crosslinkable group, but may be increased up to 10 times equivalent or may be decreased up to 1/10 equivalent.
If the amount exceeds the above range and the amount is too small, the crosslinking becomes insufficient. Further, if the amount is too large, the unreacted crosslinking agent deteriorates the photographic performance, which is not preferable.

(Dye Used in AH Layer or BC Layer as Necessary) The heat-developable material of the present invention may optionally contain an antihalation layer (AH) for preventing halation of the heat-developable material.
Layer) or a back coating layer (BC layer),
The dye used in the AH layer or BC layer may be any dye that absorbs image exposure light, and preferable examples thereof include JP-A-2-216140, JP-A-7-13295, and JP-A-7-1.
The dyes described in 1432, U.S. Pat. No. 5,380,380,635 and the like can be mentioned.

(Support) The support is preferably a support such as polyethylene terephthalate, polyethylene naphthalate or syndiotactic polystyrene.
It is preferably axially stretched or heat-fixed and has a thickness of 50 to 400 μm, which has high optical isotropy and good dimensional stability.

<Image exposure> As an exposure method, Japanese Patent Application Laid-Open No. 9-29242
No. 304869, No. 9-311403 and JP-A-2
Laser exposure can be carried out by the method described in No. 000-10230. For exposing the heat-developable material of the present invention, it is desirable to use a light source suitable for the color sensitivity imparted to the photosensitive material. For example, when the sensitive material is made to be sensitive to infrared light, it can be applied to any light source in the infrared light range, but the laser power is high power,
Infrared semiconductor lasers (780 nm, 820 nm) are more preferably used from the viewpoint that the photosensitive material can be made transparent.

<Heat Developing Device> As a device for developing a heat developing material, the devices described in JP-A Nos. 11-65067, 11-72897 and 811-4619 can be used.

[0048]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

[0049] Example 1 subjected to corona discharge treatment at 12W / m ² · min on both sides of a polyethylene terephthalate support having a thickness of 175 .mu.m <Preparation of undercoating already support> Undercoat coating solution a-1 on one side
Is coated to a dry film thickness of 0.6 μm and dried to form an undercoat layer A-1, and the undercoat coating solution b described below is provided on the opposite surface.
-1 was applied so as to have a dry film thickness of 0.6 μm and dried to form an undercoat layer B-1.

<< Undercoat coating liquid a-1 >> Butyl acrylate (30% by mass) t-Butyl acrylate (20% by mass) Styrene (25% by mass) 2-Hydroxyethyl acrylate (25% by mass) Copolymer latex liquid ( Dilute solids 30%) 15 times.

<< Undercoating Coating Liquid b-1 >> Butyl acrylate (40% by mass) Styrene (20% by mass) Glycidyl acrylate (40% by mass) Copolymer latex liquid (solid content 30%) is diluted 15 times.

Subsequently, undercoat layer A-1 and undercoat layer B-1
12 W / m ² · min of corona discharge is applied to the upper surface of the undercoat layer A-1, and the following undercoat upper layer coating solution a-2 is applied and dried on the undercoat upper layer A-2 (photosensitive layer side). Was applied to the undercoat layer B-1, and the following undercoat upper layer coating solution b-2 was applied and dried to provide an undercoat upper layer B-2 (for BC layer) having an antistatic function.

[0053]   << Undercoat upper layer coating liquid a-2 >>   1: 2 copolymer of styrene and butadiene 0.4g / m²   Butyl acrylate (30% by mass)     t-Butyl acrylate (20 mass%)     Styrene (25% by mass)     2-hydroxyethyl acrylate (20% by mass)     Methacrylic acid (5% by mass)     Copolymer latex liquid (solid content 30%) 0.3 g / m²   Silsesquioxane fine particles of the present invention (described in Table 1) 0.10 g / m²   << Undercoat upper layer coating liquid b-2 >>   1: 2 copolymer of styrene and butadiene 0.4g / m²   Conductive tin oxide fine particles (average particle diameter 16 nm) 0.023 g / m²   Butyl acrylate (30% by mass)     t-Butyl acrylate (20 mass%)     Styrene (25% by mass)     2-hydroxyethyl acrylate (20% by mass)     Methacrylic acid (5% by mass)     Copolymer latex liquid (solid content 30%) 0.3 g / m²   Silsesquioxane fine particles of the present invention (described in Table 1) 0.12 g / m² <Preparation of silver halide grain emulsion A>
Dissolve 7.5 g of nato gelatin and 10 mg of potassium bromide
After unraveling and adjusting the temperature to 28 ° C and pH to 3.0, silver nitrate
Molar ratio of 370 ml aqueous solution containing 74 g and (98/2)
PAg of an aqueous solution containing potassium bromide and potassium iodide
Controlled double jet method while keeping at 7.7
Added over 10 minutes. In sync with the addition of silver nitrate
1 × 10 sodium salt of sachloroiridium ^-6Mol /
1 mol of silver was added. Then 4-hydroxy-6-methyl
Add 0.3g of -1,3,3a, 7-tetrazaindene
Then adjust the pH to 5 with NaOH and average particle size 0.0
36 μm, variation coefficient of projected diameter area 8%, [100] plane
Cubic silver iodobromide grains having a ratio of 87% were obtained. This emulsion
After demineralization and coagulation and sedimentation using a Latin coagulant, add water.
I finished it to 160 ml.

<Preparation of Organic Silver Salt A> 111.4 g of behenic acid, 83.8 g of arachidic acid and 54.9 g of stearic acid were dissolved in 3980 ml of pure water at 80 ° C. Next, while stirring at high speed, a 1.5 molar sodium hydroxide aqueous solution 54
After adding 0.2 ml and 6.9 ml of concentrated nitric acid,
Cooled to 0 ° C. to give a sodium acidate solution. While maintaining the temperature of the above-mentioned sodium salt of an organic acid at 55 ° C., 420 ml of pure water was added to the silver halide grain emulsion A (containing 0.038 mol of silver) and stirred for 5 minutes. Next, 760.6 ml of a 1 mol silver nitrate solution was added over 2 minutes, the mixture was stirred for 20 minutes, and water-soluble salts were removed by filtration. Thereafter, washing with deionized water and filtration were repeated until the electric conductivity of the filtrate reached 2 μS / cm, and finally centrifugal dehydration and drying were performed.

<Preparation of Thermal Development Material> The silsesquioxane fine particles of the present invention (shown in Table 1) are contained on the undercoated support on the photosensitive layer side and the BC layer side as shown in Table 1. As described below, the photosensitive layer side coating and the BC layer side coating are performed, and the drying is performed on both the photosensitive layer side and the BC layer side by 45 times.
The heat development materials 101-123 were produced by carrying out at 1 ° C. for 1 minute.

<< Coating on BC layer side >> The following BC is applied on the back surface side.
A coating solution prepared as a methyl ethyl ketone (MEK) solution so as to have a layer composition and a BC layer protective layer composition was simultaneously multi-layered and dried in the following amounts to form a BC layer and a BC layer protective layer.

<< BC Layer Composition >> Binder: PVB-1 1.8 g / m ² Hexamethylene diisocyanate 1 × 10 ⁻⁴ mol / m ² Dye: C1 2.2 × 10 ⁻⁵ mol / m ² << BC Layer Protective Layer Composition >> Styrene-ethyl acrylate-acrylic acid amide copolymer 1.2 g / m ² Fine particles having silsesquioxane structure of the present invention (described in Table 1) 0.10 g / m ² << Photosensitive layer side Coating >> A coating solution prepared as a methyl ethyl ketone (MEK) solution so as to have the following AH layer composition, photosensitive layer composition, and photosensitive layer protective layer composition was coated on the photosensitive layer side in the following multi-layer coating and dried. AH layer, photosensitive layer,
A photosensitive layer protective layer was formed.

<< AH layer composition >> Binder: PVB-1 0.4 g / m ² Dye: C1 1.3 × 10 ^-5 mol / m ² << Photosensitive layer composition >> Organic silver salt A Silver amount 1.36 g / m ² m ² binder: PVB-1 2.6 g / m ² spectral sensitizing dye A1 2 × 10 ⁻⁵ mol / m ² antifoggant-1: pyridinium hydrobromide perbromide 0.3 mg / m ² antifoggant-2 : Isothiazolone 1.2 mg / m ² reducing agent: K-4 3 × 10 ^-4 mol / m ² << Photosensitive layer protective layer composition >> Styrene-ethyl acrylate-acrylic acid amide copolymer 1.2 g / m ² phthalazine 0 0.2 g / m ² 4-methylphthalic acid 0.7 g / m ² tetrachlorophthalic acid 0.2 g / m ² Silsesquioxane fine particles of the present invention (described in Table 1) 0.12 g / m ² silica (average particle diameter 3 μm ) 0.02 g / m ²

[0059]

[Chemical 8]

Evaluation Method (Photographic Performance) An unexposed sample was stored at 25 ° C. in an atmosphere of 48% relative humidity for 3 days, then exposed with a 810 nm semiconductor laser exposure sensitometer, and after exposure at 120 ° C. for 8 seconds. After heating, the fog and sensitivity of the obtained sample were determined. Laser exposure was set in double mode with an incident angle of 76 degrees.

The fog value was measured by using a fog Macbeth densitometer while setting the optical density of the undercoated support to zero.

Sensitivity The reciprocal of the exposure dose that gives an optical density of 0.3 is determined as the sensitivity, and is shown as a relative value with the sensitivity of Sample 101 being 100.

(Transportability) Image Defect After Development For the image defect after development, a sample of the heat developing material having a width of 30 cm and a length of 1 m was uniformly solid-exposed so as to have a density of 1.0 ± 0.1, and was thermally developed. After that, the number of image defects appearing due to the exfoliation of fine particles present therein was measured. Staining of Roller and Staining of Heat Development Material Sample (Film) Treatment of heat development material sample With a transportability tester having 50 mirror surface stainless rollers having a length of 20 m and a diameter of 10 cm,
While being conveyed at a speed of 100 m / min with a tension of 3 N / cm for 300 m, the contamination of the roller and the sample (film) of the heat developing material was evaluated. The dirt of the roller is 1 of the roller
The second stain was visually observed and evaluated based on the following criteria. The stain of the sample (film) of the heat developing material was evaluated by visually observing the stain on the film surface on the photosensitive layer side when passing through the 50th roller, and using the following criteria as a guide. The evaluation ranks of the roller and the heat-developable material sample were as follows: stain-free level was 5, slight stain was 4, weak stain was 3, slightly strong stain (not practical) was 2, and strong stain was 1.

The results are shown in Table 1.

[0065]

[Table 1]

* Changes in the average particle diameter of the silsesquioxane fine particles of the present invention were adjusted by the method described in the method for synthesizing fine particles described above.

From Table 1, it can be seen that when the silsesquioxane fine particles of the present invention are used, the stains on the roller and the sample are eliminated, and there is no image defect of the heat developing material. It can be seen that the photographic performance does not cause fog or sensitivity fluctuation. Further, it can be seen that the addition of the silsesquioxane fine particles of the present invention to the protective layer improves the transportability of the present invention rather than addition to the photosensitive layer or the backing layer.

Example 2 An experiment was carried out in the same manner as in Example 1, except that the silsesquioxane fine particles of the present invention and a cross-linking agent (types shown in Table 2,
Used amount: 2 × 10 ⁻³ mol / m ² ) in combination with Table 2
Used as described.

The results are shown in Table 2.

[0070]

[Table 2]

From Table 2, when the silsesquioxane fine particles of the present invention which also have a reactive group with a cross-linking agent are used in combination with the cross-linking agent, the contamination of the roller and the sample is further reduced, and the heat-developable material It can be seen that there are also fewer image defects. It can be seen that the photographic performance does not cause fog or sensitivity fluctuation.

Example 3 An experiment was conducted in the same manner as in Example 1, except that the silsesquioxane fine particles of the present invention (average particle diameter 40 nm) and the cross-linking agent (use amount: 1.5 × 10 ⁻³ mol / mol) were used. m ² ) and a surfactant having a fluorine atom (amount used: 3 × 10 ⁻³ mol / m
² ) were combined and used as described in Table 3. The amount of surfactant added was 3 × 10 ^-5 mol per square meter.

The results are shown in Table 3.

[0074]

[Table 3]

From Table 3, when the silsesquioxane fine particles of the present invention, the crosslinking agent and the surfactant having a fluorine atom are used, the contamination of the roller and the sample is further reduced,
It can be seen that there are even fewer image defects in the heat developable material.
It can be seen that there is no fog or sensitivity variation in photographic performance.

[0076]

Industrial Applicability According to the present invention, it is possible to provide a heat-developable material in which the matting agent is prevented from peeling off during the production process of the heat-developable material or during transportation on a roller in a heat-development processor, and the image defects caused by the exfoliated substance are improved. .

Claims (6)

[Claims] 1. A heat-developable material containing at least a photosensitive silver halide grain, an organic silver salt, a reducing agent and a binder on a support, the surface of which has a silsesquioxane structure substituted with a fluorine atom. A heat developable material containing fine particles. 2. The heat-developable material according to claim 1, wherein the fine particles having a silsesquioxane structure have an average particle diameter of 0.7 nm to 10 μm. 3. The photothermographic material according to claim 1, wherein the fine particles having the silsesquioxane structure are contained in the outermost layer or the undercoat layer. 4. The heat-developable material according to claim 1, wherein the fine particles having a silsesquioxane structure are covalently bonded to the binder. 5. The fine particles having a silsesquioxane structure are covalently bonded and immobilized to the binder through a crosslinking agent having an isocyanate group, a vinylsulfonyl group, an epoxy group or an alkoxysilane group. The heat developable material according to claim 4, wherein 6. The surface active agent having a fluorine atom-containing organic group in its molecule is contained in a layer in which the fine particles having a silsesquioxane structure are present. The heat-developable material as described in 1 above.