JP2001033907A - Heat-developable image recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat-developable image recording material coatable with an aqueous coating material advantageous in environmental and economical points and good in coated surface quality and low in fog and high in blacked density. SOLUTION: This heat-developable image recording material contains a reducing agent, a binder, and nonphotosensitive organic silver salt on a support, and these silver salt grains are prepared by mixing and reacting a solution containing silver ions in water or a solvent mixture of water and an organic solvent with a solution of an alkali metal salt of a fatty acid in a solvent of water or an organic solvent, or a mixture of water and an organic solvent in a tightly enclosing means.

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 image recording material for a scanner, an imagesetter, and a heat-developable image recording material suitable for photolithography. The present invention relates to a heat-developable image recording material for photoengraving and medical use which can obtain an image having a high Dmax (maximum density) with a low fog on a coated surface.

[0002]

2. Description of the Related Art There are many known photosensitive materials having a photosensitive layer on a support and forming an image by exposing the image. Among them, a technique for forming an image by thermal development is a system that can simplify environmental preservation and image forming means. 2. Description of the Related Art In recent years, there has been a strong demand in the photoengraving field and medical field to reduce the amount of processing waste liquid from the viewpoint of environmental conservation and space saving. Therefore, there is a need for a technique relating to photolithography and photothermographic materials for medical use, which can be efficiently exposed to laser light and can form a sharp black image having high resolution and sharpness. These photothermographic materials eliminate the use of solution processing chemicals, and can provide customers with a simpler and more environmentally friendly photothermographic processing system.

A method for forming an image by thermal development is described in, for example, US Pat. Nos. 3,152,904 and 3,457,075 and D.C. Morgan and B.A. Sherry (Sh
ely) "Heat treated silver system (Therm
ally Processed Silver Systems) A "(Imaging
Processings and Materials (Imaging Proce
sses and Materials) Neblette 8th edition, Sturgi (Stur
ge), V.I. Walworth, A .; Edited by Shepp, page 2, 1969). Such photosensitive materials are prepared by dispersing a reducible non-photosensitive silver source (eg, an organic silver salt), a catalytically active amount of a photocatalyst (eg, silver halide), and a silver reducing agent, usually in an organic binder matrix. It is contained in. The photosensitive material is stable at room temperature, but when heated to a high temperature (for example, 80 ° C. or higher) after exposure, silver is reduced through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and a reducing agent. Generate This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure. The silver formed by the reaction of the reducible silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image.

The silver source used in such a system is generally a silver salt of a fatty acid, and various production methods are known. For example, Japanese Patent Application Laid-Open Nos.
9-94619 and JP-A-53-68702.
For preparing an organic silver salt in a coexisting solution of water and a poorly water-soluble solvent as described in JP-A-53-31611
JP-A-54-4117 and JP-A-54-4117
No. 46709, a method for preparing an organic silver salt in an aqueous solution, JP-A-57-186745, JP-A-47-9432 and U.S. Pat.
There is a method of preparing an organic silver salt in an organic solvent as described in Japanese Patent No. 700,458. Basically, it is prepared by heating and melting the fatty acid in water above its melting point, adding sodium hydroxide or an alkali metal salt with vigorous stirring, and then adding silver nitrate to convert the alkali soap to silver soap. I do. Such an alkali soap forms micelles in an aqueous solution, and appears as a cloudy liquid. Such a reaction from the micellar state to silver soap often causes production stability problems. For this reason, Japanese Patent Application Laid-Open No. 55-40607 discloses that as a method for making the alkaline soap uniform, a solvent is used as a mixture of water and alcohol.

[0005] Alkaline soap exhibits alkalinity. Therefore, in this case, the silver soap will be made at a high pH. However, adding silver nitrate to an alkaline solution not only generates silver oxide as a by-product, but also reduces trace contaminants inevitable in production,
Due to the high pH, it has a high reducing property and causes unintended silver nuclei. Such by-products are very disadvantageous in the performance of such a heat-developable photographic material, particularly in that undesirable fogging and deterioration on the coated surface are caused. From the above viewpoint, there is a method described in JP-A-55-40607 as a method for obtaining a uniform liquid in order to suppress the generation of by-products. However, even in this method, the above problem is solved. Not. Japanese Patent Application Laid-Open No. 9-127643 discloses a method for forming a silver salt by simultaneous metered addition of an alkali metal salt solution and a silver nitrate solution. There is a description of simultaneous addition. This method can reduce the reaction at least at a high pH to a neutral range and is a preferable method for reducing the amount of silver oxide formed.However, isopropyl alcohol has a weak reducing property. It is not a means to solve, nor does it lead to improvement on the coated surface.

As described above, care must be taken in the preparation of the organic silver salt, and it is necessary to eliminate as much reducing substance as possible when forming the fatty acid silver salt, control the particle size, and further control the particle shape. There is, however, not that far with conventional methods. By the way, conventionally, most of the heat developing materials using an organic silver salt form a photosensitive layer by applying a coating solution using an organic solvent such as toluene, methyl ethyl ketone or methanol as a solvent. Using an organic solvent as a solvent means safety in the manufacturing process,
When considering the purpose of providing a photothermographic material aiming at environmental protection as well as being extremely disadvantageous in terms of cost due to adverse effects on the human body, and furthermore, recovery of the solvent, etc.
Not an appropriate manufacturing method. Therefore, a method of forming a photosensitive layer (hereinafter, also referred to as “aqueous photosensitive layer”) using a coating solution of an aqueous solvent that does not have such a problem has been considered. For example, JP-A-49-52626 and JP-A-53-116144 describe examples using gelatin as a binder. Japanese Patent Application Laid-Open No. 50-151138 discloses an example using polyvinyl alcohol as a binder.

Further, Japanese Patent Application Laid-Open No. 60-61747 discloses an example in which gelatin and polyvinyl alcohol are used in combination. As another example, JP-A-58-28737 describes an example of a photosensitive layer using a water-soluble polyvinyl acetal as a binder. When a water-soluble binder is used as described above, it is possible to form a photosensitive layer using a coating solution of a water solvent, and there are great environmental and cost advantages. However, the binder of the water-soluble polymer has poor compatibility with the organic silver salt, and further, the aqueous photosensitive layer coating solution is mainly used in an aqueous solvent also other photographic additives of the organic silver salt,
Unintended aggregation is likely to occur due to interaction with them,
It was difficult to obtain a good surface condition. In order to obtain a coating surface quality that can withstand practical use with an aqueous solvent coating solution containing a fatty acid silver salt, it is necessary that the fatty acid silver salt be finely dispersed without aggregation in an aqueous solvent. Therefore, it is necessary to develop a method for dispersing the fatty acid silver salt in fine particles. Usually, for example, the description by D. Kloosterboer (Imaging Processes and Materials (Imag)
ing Processes and Materials) Neblette 8th edition, Sturge, V. Walworth,
A. Shepp, p. 279, 1989)
After the formation of hydrophobic fatty acid silver dispersion particles as described above, filtration and separation are carried out, and a solid substance is taken out, followed by mixing with a dispersant and redispersing.

[0008] The method of dispersing the fatty acid silver salt in the form of fine particles can be carried out by a known fine-granulating means (for example, a high-speed mixer, a homogenizer, a high-speed impact mill, a Banbury mixer, a homomixer, a kneader, a ball mill, a vibration ball mill) in the presence of a dispersing aid. , Planetary ball mill, attritor, sand mill,
(Bead mill, colloid mill, jet mill, roller mill, tron mill, high-speed stone mill) are known to mechanically disperse. However, in these methods, there are many agglomerated particles, resulting in poor coated surface quality. In addition to obtaining a coating solution, it is also highly probable that the primary particles of fatty acid silver, which originally crystallized as a poorly water-soluble salt, were indiscriminately pulverized. It will be the cause. In addition, 7-1199
No. 53, Japanese Unexamined Patent Application Publication No.
JP-A-238848 discloses a method in which a fatty acid silver salt is finely dispersed by pressure treatment. However, these methods relate to a dispersion using an organic solvent as a solvent. Is what you do.

Japanese Patent Application Laid-Open No. 9-127643 discloses a method in which a fatty acid silver dispersion obtained by simultaneous metered addition of an alkali metal salt solution and a silver nitrate solution is directly desalted using dialysis or ultrafiltration. I have. This method is a preferred method in that at least the primary particles obtained during crystallization of the fatty acid silver salt are directly introduced into the photosensitive layer without damaging the primary particles,
The problems of aggregation of particles in a high salt concentration atmosphere and high viscosity in concentrating a dispersion have not been solved, and in this respect, there is no means for obtaining a practical coating solution. Further, in order to obtain fine and monodispersed fatty acid silver salt particles, it is necessary to vigorously mix the alkali metal salt solution and the silver nitrate solution while adding them. Particularly, a solution of an alkali metal salt of a fatty acid dissolved at a high temperature drops and precipitates at the moment of its addition, so that if the dilution rate or the flow is slow, it grows into large coarse particles. However, when adding to a tank having a gas / liquid interface, if the stirring speed is increased, air entrainment occurs. The fatty acid silver salt particles are extremely hydrophobic, adsorbing on the surface of the entrained foam, stabilizing the foam and preventing the foam from breaking, and causing adjacent particles on the foam to aggregate. The liquid containing air in this way becomes a whipped cream, and when desalting by-product salts by ultrafiltration, not only the handling properties are significantly deteriorated, but also the aggregated particles cause clogging. .

If the temperature of the solution after the reaction of the silver ion solution with the alkali metal salt solution of the fatty acid is high, the grains grow by physical ripening, so that the temperature is preferably maintained at about room temperature. On the other hand, in order to obtain a stable solution of a long-chain fatty acid alkali metal salt, 50
It is necessary to raise the temperature to at least ℃, and it is necessary to quickly perform heat exchange to offset the amount of heat brought by the additive liquid. In the method in which a jacket tank is attached to a tank or the like, the amount of the reaction solution increases, and the surface area for heat exchange decreases. As described above, no stable production method for liquefying a fatty acid silver salt in an aqueous solvent for supplying a heat-developable image recording material having good coated surface quality and excellent optical performance such as fog has not been found. Therefore,
There has been a demand for a technique for providing a heat-developable image recording material that can obtain good coated surface quality, has low fog, can obtain a high blackening density, and is advantageous in terms of environment and cost.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art. That is, the present invention is to provide a heat-developable image recording material which can be applied in an aqueous environment advantageous in terms of environment and cost, and has good coating surface quality, low fog and high blackening density. Issues to be solved.

[0012]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve these problems, and as a result, have found that a silver ion-containing solution is reacted with a fatty acid alkali metal salt solution to prepare fatty acid silver particles. In addition, the use of non-photosensitive organic silver salt particles prepared by mixing and reacting a fatty acid alkali metal salt solution and a silver ion-containing solution in a sealed liquid mixing means to provide a desired effect. It has been found that a heat-developable image recording material can be provided, and the present invention has been provided. That is, the present invention provides a heat-developable image recording material having a reducing agent, a binder and non-photosensitive organic silver salt particles on a support, wherein the non-photosensitive organic silver salt particles are formed of water, or a mixture of water and an organic solvent. Prepared by mixing and reacting a silver ion-containing solution using the mixture as a solvent and a solution of a fatty acid alkali metal salt using water, an organic solvent or a mixture of water and an organic solvent as a solvent in a closed mixing means. And a heat-developable image recording material.

In a preferred embodiment of the present invention, the non-photosensitive organic silver salt particles are prepared by a method comprising cooling the reacted reaction mixture after carrying out the reaction in the liquid mixing means. Preferably, the heat-developable image recording material of the present invention further contains a photosensitive silver halide. Preferably, in the heat-developable image recording material of the present invention, the binder of the image forming layer containing the non-photosensitive organic silver salt particles is used as a binder.
0% by weight or more and glass transition temperature of -30 ° C or more and 40
Use a polymer latex at or below ° C. Preferably, the heat-developable image recording material of the present invention contains at least one nucleating agent in at least one layer on the side of the image forming layer on the support. Preferably, the nucleating agent is selected from a substituted alkene derivative represented by the following formula (1), a substituted isoxazole derivative represented by the following formula (2), or a specific acetal compound represented by the following formula (3) At least one compound.

[0014]

Embedded image

[In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ² and R ³ , R ¹ and R ² , and R ³ and Z may be bonded to each other to form a cyclic structure. In the formula (2), R ⁴ represents a substituent. In formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic ring. Represents an oxy group, a heterocyclic thio group or a heterocyclic amino group. In the formula (3), X and Y, and A
And B may combine with each other to form a cyclic structure. ]

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method and an embodiment of the heat-developable image recording material of the present invention will be described in detail. The heat-developable image recording material of the present invention, as a non-photosensitive organic silver salt particles, water, or a silver ion-containing solution using a mixture of water and an organic solvent as a solvent, water, an organic solvent or water and an organic solvent. In the method of preparing fatty acid silver particles by reacting a solution of a fatty acid alkali metal salt using a mixture as a solvent, the silver ion-containing solution and the fatty acid alkali metal salt solution are mixed and reacted in a closed mixing means. A non-photosensitive organic silver salt particle prepared by a method characterized by the above feature is used. FIG. 1 shows a schematic diagram of a method for preparing a non-photosensitive fatty acid silver salt used in the present invention. 1 is a mixing device that is closed and filled with a liquid, and 2 is a heat exchanger.
In the figure, A is a silver ion-containing solution, B is a fatty acid alkali metal salt solution, C is water, a mixed solution of water and an organic solvent, or a non-photosensitive fatty acid silver salt particle solution after the reaction. These liquids merge in the mixing device to prepare a fatty acid silver salt liquid D, which is then sent to the heat exchanger 2 and cooled.

FIG. 2 shows an embodiment of the method for preparing the non-photosensitive fatty acid silver salt used in the present invention. In FIGS. 11 and 12, silver ion-containing solution and fatty acid alkali metal salt solution are stored at a predetermined temperature, respectively. 13 and 14
Is a flow meter for measuring the flow rate when these solutions are added to the sealed and liquid-filled mixing device 18 via the pumps 15 and 16. In this embodiment,
As a third component, a pump 17 for supplying the prepared fatty acid silver salt dispersion to the mixing device 18 again is provided. The liquid that has completed the reaction in the mixing device 18 is introduced into the heat exchanger 19 and quickly cooled. The pH of the silver ion-containing solution used in the present invention is preferably pH 1 or more and 6 or less, more preferably pH 1.5 or more and 4 or less. Further, acids and alkalis can be added for pH adjustment. The type of acid and alkali is not particularly limited.

The silver ion concentration of the silver ion-containing solution used in the present invention is arbitrarily determined.
It is preferably from 03 mol / L to 6.5 mol / L, more preferably from 0.1 mol / L to 5 mol / L. In the practice of the present invention, in order to form fatty acid salt particles, at least one of a silver ion solution, a fatty acid alkali metal salt solution, and a solution prepared in advance in a reaction field has a string form of an alkali metal salt of a fatty acid. It must contain an amount of organic solvent that is not coalesced or micelles, but can be a substantially clear solution. The solution may be an organic solvent alone, but is preferably a mixed solution with water. The type of the organic solvent used in the present invention is not particularly limited as long as it is water-soluble and has the above-mentioned properties. Preferably 4 to 4 carbon atoms
A tertiary alcohol of 6 is preferred. In addition, the fatty acid used is relatively stable to light when made into a silver salt,
A silver salt that 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. Fatty acids are in particular long-chain fatty carboxylic acids having 10 to 30 carbon atoms, preferably 12 to 26 carbon atoms. Preferred examples of the aliphatic carboxylic acid include serotic acid, lignoceric acid, behenic acid, erucic acid, arachidic acid, stearic acid, oleic acid, lauric acid, caproic acid, myristic acid, palmitic acid,
Mention may be made of maleic acid, fumaric acid, tartaric acid, linoleic acid, butyric acid and camphoric acid, and mixtures thereof.

As the alkali metal of the alkali metal salt of a fatty acid used in the present invention, specifically, Na and K are preferable. Alkali metal salts of fatty acids include NaOH or KO as fatty acids.
Prepared by adding H. At this time, it is preferable to make the amount of alkali less than or equal to the equivalent of fatty acid so that unreacted fatty acid remains. In this case, the amount of the residual fatty acid is 3 mol% or more and 50 mol% or less, preferably 3 mol% or more and 30 mol% or less based on the total fatty acids. Alternatively, after the alkali is added in a desired amount or more, an acid such as nitric acid or sulfuric acid may be added to neutralize excess alkali. Further, the silver ion-containing solution and the fatty acid alkali metal salt solution used in the present invention, or the solution in a closed mixing vessel to which both solutions are added, are represented by, for example, the general formula (1) of JP-A-62-65035. Such a compound, a water-soluble group-containing N-heterocyclic compound as described in JP-A-62-150240,
Inorganic peroxides as described in JP-A-101019.
A sulfur compound as described in JP-A-51-78319, a disulfide compound and hydrogen peroxide as described in JP-A-57-643 can be added.

In the fatty acid alkali metal salt solution used in the present invention, the amount of the organic solvent is preferably 3% or more and 70% or less, more preferably 5% or more and 50% or less as the solvent volume with respect to the volume of water. is there. At this time, since the optimum solvent volume changes depending on the reaction temperature, the optimum amount can be determined by trial and error. The concentration of the alkali metal salt of a fatty acid used in the present invention is 5% by weight or more and 50% by weight or less, preferably 7% by weight or more and 45% by weight or less.
wt% or less, more preferably 10 wt% or more.
0 wt% or less.

A desired fatty acid silver salt can be prepared by simultaneously adding the silver ion-containing solution and the fatty acid alkali metal salt solution used in the present invention. At this time, it is preferable that 10% or more and 100% or less of the total added silver amount is added simultaneously with the solution of the alkali metal salt of fatty acid having almost the same mole, and it is more preferable that 30% or more and 100% or less are added simultaneously. , 50% or more and 100% or less are particularly preferably added simultaneously. When any of them is preferentially added, it is preferable to precede the solution containing a silver ion. The silver ion-containing solution and the fatty acid alkali metal salt solution used in the present invention can be adjusted to an appropriate temperature in order to obtain desired particles. The temperature of the silver ion-containing solution is preferably from 5 ° C. to 60 ° C., more preferably from 5 ° C. to 40 ° C. for the purpose of ensuring the stability of the solution. The fatty acid alkali metal salt solution is preferably at least 50 ° C. and at most 90 ° C., more preferably at least 60 ° C. and at most 85 ° C., in order to maintain the temperature range necessary for avoiding the phenomenon of alkali soap crystallization and solidification. .

The temperature of the reaction solution during silver salt formation may be any temperature, but is preferably 5 ° C. to 70 ° C., more preferably 10 ° C. to 50 ° C., and particularly preferably 20 ° C. to 4 ° C.
When the temperature is 5 ° C. or lower, the performance as an image recording material can be further improved. There are various approaches to forming fatty acid silver salt particles. In order to obtain the particles used in the present invention, it is preferable to reduce the solubility of the fatty acid salt in the reaction field. According to the study of the present inventors, it has been revealed that the fatty acid silver salt particles tend to decrease in size as the reaction time increases. In order to obtain the desired particle size, it is necessary to determine the reaction time by trial and error. There is no limitation on the device to which the reaction solution is added. In particular, for the mixing device, for example, a bulk stirrer such as an anchor blade or a paddle blade, an emulsifying / dispersing device such as a dissolver or a homogenizer, a static mixer such as a static mixer or a sluzer mixer, or any combination thereof is used. it can.

The order of addition of the silver ion solution and the alkali metal salt solution of the fatty acid may be, for example, a method of adding two solutions to the same mixing device, or adding either one upstream of the mixing device and adding only one solution to the mixing device. Addition method, water or mixed solution with silver ion solution and organic solvent used for alkali metal salt solution of fatty acid, and 3 solutions including non-photosensitive fatty acid silver salt particle solution after reaction are added to the same mixing apparatus. Method: Add 3 liquids in any order upstream of the mixing device and add 1
Any method can be used, such as a method of adding only a liquid or a method of arranging a plurality of mixing devices in series and adding one or two liquids to each. The addition time of the silver ion solution and the fatty acid alkali metal salt solution can also be arbitrarily selected. For example, the addition may be performed at a constant addition rate, or in an acceleration or deceleration mode by an arbitrary time function.

In order to rapidly lower the liquid temperature after the reaction between the silver ion solution and the alkali metal salt solution of the fatty acid, the silver ion solution to be supplied to the mixing device, water or a mixed solution of water and an organic solvent or A method of cooling the mixing device itself or a method of providing a heat exchanger between the mixing device and the tank other than a method of previously cooling the fatty acid silver salt particle liquid later can be adopted. The liquid temperature after the reaction of the silver ion liquid and the alkali metal salt liquid of the fatty acid is preferably 5 ° C or more and 70 ° C or less, more preferably 10 ° C or more and 50 ° C or less, and particularly preferably 2 ° C or less.
It is 0 ° C or more and 45 ° C or less. The cooling rate is 0.05 to 10 seconds after the reaction liquids meet, preferably 0.0 to 10 seconds.
By reaching the target temperature in 5 seconds to 5 seconds, more preferably 0.05 seconds to 1 second, the performance of the image recording material can be further improved. The shape of the fatty acid silver salt that can be used in the present invention is not particularly limited, but flake-like particles or needle-like crystals are preferred. The sphere equivalent diameter of the fatty acid silver salt particles prepared by the above method is preferably from 0.1 μm to 0.8 μm, more preferably from 0.1 μm to 0.6 μm. Further, the ratio of the long side / short side of the particles is preferably 1 or more and 4 or less.
It is more preferably at least 3 and at most 3, particularly preferably at least 1 and at most 2. Also, the particle aspect ratio (particle size of the main plane (equivalent circle diameter) / particle thickness)
Is preferably 2 or more and 30 or less, and 2 or more and 15 or less.
It is more preferred that: Further, the thickness of the particles is preferably 0.01 μm or more and 0.20 μm or less, more preferably 0.01 μm or more and 0.15 μm or less. It is preferable that grains satisfying the above requirements be included in the range of 30% to 100% of the projected area of all grains.
% Or more, and more preferably 70% or more and 100% or less.

The particle size distribution of the fatty acid silver salt is preferably as monodisperse as possible. Assuming that the coefficient of variation is 100 times the value obtained by dividing the standard deviation of the particle diameter by the particle diameter, the coefficient of variation of the particle size of the fatty acid silver salt particles is preferably 20% or less, more preferably 18% or less, and still more preferably 1% or less.
5% or less. As a measurement method, for example, the particle size (volume weight average diameter) obtained by irradiating a fatty acid silver salt dispersed in a liquid with a laser beam and obtaining an autocorrelation function with respect to a time change of fluctuation of the scattered light is obtained. (So-called dynamic light scattering method). The fatty acid silver salt that can be used in the present invention can be desalted preferably. There is no particular limitation on the method for performing desalting, and a known method can be used.A known filtration method such as centrifugal filtration, suction filtration, ultrafiltration, or floc-forming water washing by a coagulation method can be preferably used. . Ultrafiltration is particularly preferred. For the ultrafiltration, for example, a method used for desalting / concentrating a silver halide emulsion can be applied.
Research Disclosur
e) No. 10 208 (1972), No. 13 12
2 (1975) and No. 16 351 (1977)
It has been known. The pressure difference and flow rate, which are important as operating conditions, can be selected with reference to the characteristic curve described in “Handbook of Membrane Utilization Technology” written by Haruhiko Oya, Koshobo Publishing (1978), p.275. In processing, it is necessary to find optimal conditions for suppressing aggregation and fogging of particles. In addition, in the method of replenishing the solvent that is lost due to membrane permeation, there are a constant volume type in which the solvent is continuously added and a batch type in which the solvent is added intermittently. Equations are preferred. Pure water obtained by ion exchange or distillation is used as the solvent to be replenished in this manner. In order to maintain the pH, the dispersant concentration and the concentration of the poor solvent with respect to the dispersant at the target values of the present invention, pure water is used. May be mixed with a pH adjuster, a dispersant, and a poor solvent for the dispersant, or may be added directly to the fatty acid silver dispersion.

The ultrafiltration membrane is a flat type, a spiral type, a cylindrical type, a hollow fiber type already incorporated as a module,
Hollow fiber type is commercially available from Asahi Kasei Co., Ltd., Daicel Chemical Co., Ltd., Toray Co., Ltd., Nitto Denko Co., Ltd. Is preferred. In addition, the molecular weight cutoff as an index of the threshold value of the component that can pass through the membrane needs to be determined from the molecular weight of the dispersant used. In the present invention, those having a molecular weight of 5,000 to 50,000, preferably 5,000 to 15,000 are used. A water-soluble dispersant can be added to the silver ion-containing solution and the fatty acid alkali metal salt solution or the reaction solution used in the present invention. Therefore, it can be added to the reaction solution at the time of forming the fatty acid silver salt, a separately prepared dispersant solution, and the solution after the formation of the fatty acid silver salt. The type of the dispersant is not particularly limited as long as it can disperse the formed fatty acid silver salt. Specific examples are in accordance with the description of the fatty acid silver salt dispersant described below.

The fatty acid silver salt which can be used in the present invention may be a method of preparing a solid fine particle dispersion using a dispersant for the purpose of obtaining fine particles having a small particle size and without aggregation. When preparing this solid fine particle dispersion, it is preferable that the formed particles are not broken and only aggregation is eliminated. This is the TE of the particles before washing.
The determination can be made by comparing the M photograph with the TEM photograph of the dispersed particles. In the particles used in the present invention, when comparing the average particle size before water washing and the average particle size after dispersion, it is preferable that the projected area does not change by 30% or more.
It is more preferable that the change does not change by 0% or more, and it is particularly preferable that the change does not change by 10% or more. As the dispersion method, it is preferable to use a method of converting the aqueous dispersion of the fatty acid silver salt into a high-pressure / high-speed stream and then reducing the pressure. Further, when a photosensitive silver salt is present in the dispersion, fog increases and the sensitivity is remarkably reduced. Therefore, it is more preferable that the photosensitive silver salt is not substantially contained during the dispersion. In the present invention, the amount of the photosensitive silver salt in the aqueous dispersion to be dispersed is 0.1 mol% or less based on 1 mol of the fatty acid silver salt in the liquid, and the photosensitive silver salt is not actively added. Things.

In the present invention, the dispersing apparatus and the technique used for carrying out the dispersing method as described above are described in, for example, "Dispersion Rheology and Dispersion Technology" (Toshio Kajiuchi and Hiroki Usui, 1991; Sansha Publishing Co., Ltd., p3
57-403), "Progress in Chemical Engineering, Vol. 24," edited by The Society of Chemical Engineers, Tokai Branch, 1990, Maki Shoten, p1
84-185), etc., but the dispersion method in the present invention is as follows.
After pressurizing an aqueous dispersion containing at least a fatty acid silver salt with a high-pressure pump or the like and feeding the same into a pipe, pass through a narrow slit provided in the pipe, and then cause a sharp pressure drop in the dispersion. This is a method of performing finer dispersion.
The high-pressure homogenizer to which the present invention relates is generally (a) a "shear force" generated when the dispersoid passes through a narrow gap at a high pressure and a high speed, and (b) the dispersoid is released from a high pressure to a normal pressure. It is considered that dispersion into fine particles is performed by dispersing force such as “cavitation force” generated at the time. An example of this type of dispersing device is a Gaulin homogenizer. The particles collide and are emulsified and dispersed by the impact force. Working pressure is generally 100 to 600
kg / cm ² , the flow velocity is in the range of several m to 30 m / sec. In order to increase the dispersion efficiency, a high-speed flow part having a saw blade shape to increase the number of collisions has been devised. On the other hand, devices capable of dispersing at higher pressures have been developed in recent years, and typical examples are microfluidizers (Microfluidex International Corporation) and nanomizers (Tokusai Kika Kogyo Co., Ltd.). And the like.

The silver salt of fatty acid used in the present invention can be dispersed into a desired particle size by adjusting the flow rate, the differential pressure at the time of pressure drop, and the number of treatments. Is 200m / sec to 600m / sec,
The pressure difference at the time of pressure drop is preferably in the range of 900 to 3000 kg / cm ² , and the flow rate is preferably 300 to 600 m / sec.
Second, the differential pressure at the time of pressure drop is 1500-3000 kg / cm ²
More preferably, it is within the range. The number of times of the dispersion treatment can be selected as needed. Usually, the range of 1 to 10 times is selected, but from the viewpoint of productivity, about 1 to 3 times is selected. It is not preferable to raise the temperature of such an aqueous dispersion under high pressure from the viewpoint of dispersibility and photographic properties. is there. Therefore, in the present invention, the high pressure, a step before converting to a high-speed flow, a step after the pressure is reduced, or a cooling device in both these steps,
The temperature of such water dispersion is 5 ° C to 90 ° C depending on the cooling step.
, And more preferably in the range of 5 ° C to 80 ° C, particularly preferably in the range of 5 ° C to 65 ° C. In particular, 1500-3000k
At the time of high-pressure dispersion in the range of g / cm ² , it is effective to provide the above cooling step. As the cooling device, a device using a static mixer for a double tube or a triple tube, a multi-tube heat exchanger, a coiled tube heat exchanger, or the like can be appropriately selected according to the required heat exchange amount. Further, in order to increase the efficiency of heat exchange, it is only necessary to select a suitable one such as a pipe thickness, a wall thickness and a material in consideration of a working pressure. The refrigerant used in the cooler was treated with well water at 20 ° C or a refrigerator based on the amount of heat exchanged.
Refrigerant such as cold water at 〜１０10 ° C. and ethylene glycol / water at -30 ° C. can be used if necessary.

Examples of the dispersant include synthetic anionic polymers such as polyacrylic acid, a copolymer of acrylic acid, a maleic acid copolymer, a maleic acid monoester copolymer, and an acryloylmethylpropanesulfonic acid copolymer.
Semi-synthetic anionic polymers such as carboxymethyl starch and carboxymethyl cellulose; anionic polymers such as alginic acid and pectic acid;
6, anionic surfactants described in International Publication No. WO88 / 04794 and the like, JP-A-9-17924.
No. 3 or a known anionic compound,
Nonionic, cationic surfactants, and other known polymers such as polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, hydroxypropylcellulose, and hydroxypropylmethylcellulose, or naturally occurring polymer compounds such as gelatin are appropriately selected and used. be able to. The concentration of the dispersant is preferably in the range of 1 to 30% by weight, particularly preferably 3 to 20% by weight, based on the fatty acid silver salt. The prepared dispersion is stored with stirring for the purpose of suppressing sedimentation of fine particles during storage, or stored in a highly viscous state by a hydrophilic colloid (for example, in a jelly state using gelatin). You can also. Further, a preservative can be added for the purpose of preventing the propagation of various bacteria during storage.

The fatty acid silver salt dispersion used in the present invention comprises at least a fatty acid silver salt and water. The ratio between the fatty acid silver salt and water is not particularly limited, but when considering efficient coating film formation, the rheological properties for performing stable coating, and the production speed determined by the amount of dry moisture, You need to decide. The ratio of the fatty acid silver salt to the whole is preferably 10 to 50% by weight,
In particular, it is preferably from 10 to 30% by weight. The electric conductivity of the dispersion is preferably 500 μS / cm or less, more preferably 1 to 500 μS / cm. In the preparation of the fatty acid silver salt used in the present invention, Ca, Mg, C
It is preferable to add a metal ion selected from e, Al, Zn, and Ba in the form of a water-soluble salt that is not a halide. Specifically, it is preferable to add in the form of nitrate or sulfate. Ca, Mg, Ce, Al, Zn, Ba
The addition time of the metal ion selected from the method is as follows: in the solution of the method of preparing the fatty acid silver salt, or before addition to the reaction solution, during the formation of the fatty acid silver salt, immediately after the formation, or immediately before the coating such as before and after the preparation of the coating solution. It may be time. The addition amount is preferably from 10 ^-3 to 10 ^-1 mol, particularly preferably from 5 x 10 ^{-3 to} 5 x 10 ^-2 mol, per mol of the silver salt of fatty acid.

The apparatus for carrying out the method for preparing a fatty acid silver salt used in the present invention is not particularly limited, but a preferred apparatus is a silver ion-containing solution using water or a mixture of water and an organic solvent as a solvent. Supply means for supplying a solution of a fatty acid alkali metal salt using water, an organic solvent, or a mixture of water and an organic solvent to the closed mixing means; water, or Third supply means for supplying a mixture of water and an organic solvent to the closed mixing means; and non-photosensitive fatty acid by mixing the supplies from the first supply means, the second supply means and the third supply means An apparatus for preparing non-photosensitive fatty acid silver salt particles, which has a closed mixing means for discharging a liquid containing silver salt particles, can be exemplified. This apparatus preferably further comprises a cooling means for cooling the liquid containing non-photosensitive fatty acid silver salt particles discharged from the closed mixing means (FIG. 3).

Another preferred apparatus for preparing the organic silver salt used in the present invention is a first apparatus for supplying a silver ion-containing solution containing water or a mixture of water and an organic solvent to a closed mixing means. Supply means; second supply means for supplying a solution of a fatty acid alkali metal salt using water, an organic solvent, or a mixture of water and an organic solvent as a solvent to the closed mixing means; the first supply means, the second supply means, and A closed mixing means for mixing a supply from the third supply means to discharge a non-photosensitive fatty acid silver salt particle-containing liquid; and at least a non-photosensitive fatty acid silver salt particle-containing liquid discharged from the closed mixing means. An apparatus for preparing non-photosensitive fatty acid silver salt particles, which has a third supply means for supplying a part to the closed mixing means, may also be mentioned. The apparatus preferably further comprises a cooling means for cooling the liquid containing non-photosensitive fatty acid silver salt particles discharged from the closed mixing means (FIG. 2). In the apparatus shown in FIG. 2, a dispersion of non-photosensitive fatty acid silver salt particles having a desired concentration is obtained by appropriately adjusting the amount of the non-photosensitive fatty acid silver salt particle-containing liquid supplied from the third supply means to the closed mixing means. Can be prepared in the tank 20.
That is, since the concentration of the dispersion of the non-photosensitive fatty acid silver salt particles in the tank 20 is increased by repeating the circulation using the third supply means, the dispersion having the desired concentration can be obtained by appropriately selecting the circulation conditions. A liquid can be obtained. Further, the concentration can be adjusted by adjusting not only the circulation conditions but also the conditions for taking out the prepared dispersion liquid. By appropriately selecting these conditions,
A desired dispersion can be efficiently obtained while performing continuous operation.

The heat-developable image recording material of the present invention preferably contains a nucleating agent in at least one layer on the image forming layer side in order to obtain photographic performance with high sensitivity, high contrast and high blackening density. Although the type of the nucleating agent is not particularly limited, particularly, the substituted alkene derivative represented by the formula (1),
A substituted isoxazole derivative represented by the formula (2) and a specific acetal compound represented by the formula (3) are preferable. Hereinafter, the substituted alkene derivative represented by the formula (1), the substituted isoxazole derivative represented by the formula (2), and the specific acetal compound represented by the formula (3) used in the present invention will be described.

[0035]

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In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ²
And R ³ , R ¹ and R ² , or R ³ and Z may combine with each other to form a cyclic structure. In the formula (2), R
⁴ represents a substituent. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, and a heterocyclic ring. Represents an oxy group, a heterocyclic thio group, or a heterocyclic amino group. In equation (3), X and Y or A
And B may combine with each other to form a cyclic structure.

The compound represented by the formula (1) will be described in detail. In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ² and R
³ , R ¹ and R ² , or R ³ and Z may be bonded to each other to form a cyclic structure.

When R ¹ , R ² and R ³ represent a substituent, examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom) and an alkyl group (a cycloalkyl group, An active methine group, etc.), an aralkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (including an N-substituted nitrogen-containing heterocyclic group) and a heterocyclic group containing a quaternized nitrogen atom ( For example, a pyridinio group), an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a carboxy group or a salt thereof, an imino group, an imino group substituted with an N atom, a thiocarbonyl group, a sulfonylcarbamoyl group, an acylcarbamoyl group, Famoylcarbamoyl group, carbazoyl group, oxalyl group, oxamoyl group, cyano group, thiocarbamoyl group, A droxy group or a salt thereof, an alkoxy group (including a group repeatedly containing an ethyleneoxy group or a propyleneoxy group unit), an aryloxy group, a heterocyclic oxy group, an acyloxy group, an (alkoxy or aryloxy) carbonyloxy group, and a carbamoyloxy group , Sulfonyloxy group, amino group, (alkyl, aryl, or heterocycle) amino group, acylamino group, sulfonamide group, ureido group, thioureido group, imide group, (alkoxy or aryloxy)
Carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, 4
Grade ammonio group, oxamoylamino group, (alkyl or aryl) sulfonyluureido group, acylureido group, acylsulfamoylamino group, nitro group, mercapto group, (alkyl, aryl, or heterocycle)
Thio group, acylthio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or a salt thereof, sulfamoyl group, acylsulfamoyl group, sulfonylsulfamoyl group or a salt thereof, phosphoryl group, phosphorus Examples include groups having an acid amide or phosphate structure, silyl groups, stannyl groups, and the like. These substituents may be further substituted with these substituents.

The electron-withdrawing group represented by Z in the formula (1) is a substituent whose Hammett's substituent constant σ _p can take a positive value, specifically, a cyano group, an alkoxy group or an alkoxy group. Carbonyl group, aryloxycarbonyl group, carbamoyl group, imino group, imino group substituted by N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, halogen atom,
A perfluoroalkyl group, a perfluoroalkaneamide group, a sulfonamide group, an acyl group, a formyl group, a phosphoryl group, a carboxy group (or a salt thereof), a sulfo group (or a salt thereof), a heterocyclic group, an alkenyl group, an alkynyl group, Examples include an acyloxy group, an acylthio group, a sulfonyloxy group, and an aryl group substituted with these electron-withdrawing groups. Here, the heterocyclic group is a saturated or unsaturated heterocyclic group, for example, a pyridyl group, a quinolyl group,
Examples thereof include a pyrazinyl group, a quinoxalinyl group, a benzotriazolyl group, an imidazolyl group, a benzimidazolyl group, a hydantoin-1-yl group, a succinimide group, and a phthalimido group.

The electron-withdrawing group represented by Z in the formula (1) may further have a substituent, and the substituent includes R ¹ , R ² and R ^{3 in the} formula (1). The same substituents as the substituents that may be present when representing the substituents are exemplified. In the formula (1), R ¹ and Z, R ² and R ³ , R ¹ and R ² , or R ³ and Z
May combine with each other to form a cyclic structure,
The cyclic structure formed at this time is a non-aromatic carbon ring or a non-aromatic hetero ring. Next, a preferable range of the compound represented by the formula (1) will be described. Preferable examples of the silyl group represented by Z in the formula (1) specifically include a trimethylsilyl group, a t-butyldimethylsilyl group, a phenyldimethylsilyl group, a triethylsilyl group, a triisopropylsilyl group, and a trimethylsilyldimethylsilyl group. .

The electron-withdrawing group represented by Z in the formula (1) is preferably a group having a total number of carbon atoms of 0 to 30, that is, a cyano group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, a thiol group. Carbonyl group,
Imino group, imino group substituted by N atom, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group, acyl group, formyl group, phosphoryl group, acyloxy group, acylthio group, or any electron withdrawing And a phenyl group substituted with a functional group, more preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, an imino group, a sulfamoyl group,
An alkylsulfonyl group, an arylsulfonyl group, an acyl group, a formyl group, a phosphoryl group, a trifluoromethyl group, or a phenyl group substituted with an arbitrary electron-withdrawing group, and particularly preferably a cyano group, a formyl group, an acyl group. , An alkoxycarbonyl group, an imino group or a carbamoyl group. The group represented by Z in the formula (1) is more preferably an electron-withdrawing group.

The substituent represented by R ¹ , R ² and R ³ in the formula (1) is preferably a group having a total carbon number of 0 to 30, specifically, Z in the above formula (1). A group having the same meaning as the electron-withdrawing group represented, and an alkyl group, a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, Heterocyclic thio group, amino group, alkylamino group, arylamino group, heterocyclic amino group, ureido group, acylamino group, sulfonamide group,
Or a substituted or unsubstituted aryl group. Further, in the formula (1), R ¹ is preferably an electron-withdrawing group, an aryl group, an alkylthio group, an alkoxy group, or an acylamino group, a hydrogen atom, or a silyl group. When R ¹ represents an electron-withdrawing group, the following groups having preferably 0 to 30 carbon atoms in total, that is, a cyano group, a nitro group, an acyl group, a formyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a thiocarbonyl group , Imino group, N
An atom-substituted imino group, an alkylsulfonyl group, an arylsulfonyl group, a carbamoyl group, a sulfamoyl group, a trifluoromethyl group, a phosphoryl group, a carboxy group (or a salt thereof), or a saturated or unsaturated heterocyclic group; Preferred are a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, a carbamoyl group, an imino group, an imino group substituted with an N atom, a sulfamoyl group, a carboxy group (or a salt thereof), or a saturated or unsaturated heterocyclic group. Particularly preferably, a cyano group,
A formyl group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, or a saturated or unsaturated heterocyclic group.

When R ¹ represents an aryl group, it is preferably a substituted or unsubstituted phenyl group having a total of 6 to 30 carbon atoms. Examples of the substituent include any substituent.
Among them, an electron-withdrawing substituent is preferable. In formula (1), R ¹ is more preferably an electron-withdrawing group or an aryl group. The substituents represented by R ² and R ³ in the formula (1) are preferably specifically represented by the above-mentioned formula (1)
A group having the same meaning as the electron-withdrawing group represented by Z, an alkyl group,
Hydroxy group (or salt thereof), mercapto group (or salt thereof), alkoxy group, aryloxy group, heterocyclic oxy group, alkylthio group, arylthio group, heterocyclic thio group, amino group, alkylamino group, anilino group, hetero Examples include a cyclic amino group, an acylamino group, and a substituted or unsubstituted phenyl group. In the formula (1), R ² and R ³ are
More preferably, one of them is a hydrogen atom and the other represents a substituent. Preferably as the substituent,
Alkyl group, hydroxy group (or a salt thereof), mercapto group (or a salt thereof), alkoxy group, aryloxy group,
Heterocyclic oxy group, alkylthio group, arylthio group,
A heterocyclic thio group, an amino group, an alkylamino group, an anilino group, a heterocyclic amino group, an acylamino group (particularly a perfluoroalkaneamide group), a sulfonamide group, a substituted or unsubstituted phenyl group, or a heterocyclic group; More preferably, a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group, Particularly preferred are a hydroxy group (or a salt thereof), an alkoxy group, and a heterocyclic group.

In the formula (1), it is also preferable that Z and R ¹ , or R ² and R ³ form a cyclic structure. The cyclic structure formed in this case is a non-aromatic carbocyclic or non-aromatic heterocyclic ring, preferably a 5- to 7-membered cyclic structure having a total carbon number including a substituent of 1 to 7. 40,
Further, 3 to 30 is preferable. Among the compounds represented by the formula (1), one of the more preferable ones is that Z represents a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, an imino group, or a carbamoyl group, and R ¹ represents an electron-withdrawing group. R ² or R ³ is a hydrogen atom and the other is a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group , An alkylthio group, an arylthio group, a heterocyclic thio group, or a heterocyclic group. Furthermore, one of the particularly preferable compounds represented by the general formula (1) is that Z and R ^{1 form a} non-aromatic 5- to 7-membered cyclic structure, and R ² or R ^{2 One of the three} is a hydrogen atom, the other is a hydroxy group (or a salt thereof), a mercapto group (or a salt thereof), an alkoxy group, an aryloxy group, a heterocyclic oxy group, an alkylthio group, an arylthio group, a heterocyclic thio group Or a compound representing a heterocyclic group. At this time, the Z to form a cyclic structure of the non-aromatic with R ^1, an acyl group, a carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group, and the like are preferable, and as R ¹ is acyl group,
A carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted with an N atom, an acylamino group, a carbonylthio group, and the like are preferable.

Next, the compound represented by the formula (2) will be described. In the formula (2), R ⁴ represents a substituent. As the substituent represented by R ⁴ , the same substituents as described for the substituents R ^{1 to} R ^{3 in} the formula (1) can be mentioned. The substituent represented by R ⁴ is preferably an electron-withdrawing group or an aryl group. When R ⁴ represents an electron-withdrawing group, preferably the following groups having a total carbon number of 0 to 30, ie, a cyano group, a nitro group,
Acyl group, formyl group, alkoxycarbonyl group, aryloxycarbonyl group, alkylsulfonyl group, arylsulfonyl group, carbamoyl group, sulfamoyl group, trifluoromethyl group, phosphoryl group, imino group,
Or a saturated or unsaturated heterocyclic group, more preferably a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, a carbamoyl group, a sulfamoyl group, an alkylsulfonyl group, an arylsulfonyl group, or a heterocyclic group. Particularly preferred are a cyano group, a formyl group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, and a heterocyclic group.

[0046] When R ⁴ represents an aryl group, preferably a total carbon number of 0 to 30, a substituted or unsubstituted phenyl group, the substituent, R ^1, R ^2, R ³ of formula (1) When represents a substituent, the same as those described as the substituent can be mentioned. R ⁴ is particularly preferably a cyano group, an alkoxycarbonyl group, a carbamoyl group, a heterocyclic group, or a substituted or unsubstituted phenyl group, and most preferably a cyano group, a heterocyclic group, or an alkoxycarbonyl group.

Next, the compound represented by the formula (3) will be described in detail. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent:
Represents an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group. X and Y or A and B may be bonded to each other to form a cyclic structure. As the substituents represented by X and Y in the formula (3), the same substituents as described for the substituents R ^{1 to} R ^{3 in} the formula (1) can be mentioned. Specifically, alkyl groups (including perfluoroalkyl groups, trichloromethyl groups, etc.), aryl groups, heterocyclic groups, halogen atoms, cyano groups, nitro groups, alkenyl groups, alkynyl groups, acyl groups, formyl groups, alkoxy groups Carbonyl group, aryloxycarbonyl group, imino group, imino group substituted with an N atom, carbamoyl group, thiocarbonyl group, acyloxy group, acylthio group, acylamino group,
Alkylsulfonyl, arylsulfonyl, sulfamoyl, phosphoryl, carboxy (or salt thereof), sulfo (or salt thereof), hydroxy (or salt thereof), mercapto (or salt thereof), alkoxy, aryl Oxy group, heterocyclic oxy group, alkylthio group, arylthio group, heterocyclic thio group, amino group,
Examples thereof include an alkylamino group, an anilino group, a heterocyclic amino group, and a silyl group.

These groups may further have a substituent. X and Y may be bonded to each other to form a cyclic structure, and the cyclic structure formed in this case may be a non-aromatic carbon ring or a non-aromatic hetero ring. . In formula (3), the substituents represented by X and Y are
It is preferably a group having 1 to 40 carbon atoms in total, more preferably a group having 1 to 30 carbon atoms in total, and is a cyano group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group,
Imino group, imino group substituted by N atom, thiocarbonyl group, sulfamoyl group, alkylsulfonyl group, arylsulfonyl group, nitro group, perfluoroalkyl group,
Examples include an acyl group, a formyl group, a phosphoryl group, an acylamino group, an acyloxy group, an acylthio group, a heterocyclic group, an alkylthio group, an alkoxy group, and an aryl group.

In the formula (3), X and Y are more preferably cyano, nitro, alkoxycarbonyl, carbamoyl, acyl, formyl, acylthio, acylamino, thiocarbonyl, sulfamoyl, alkylsulfonyl. Group, an arylsulfonyl group, an imino group, an imino group substituted with an N atom, a phosphoryl group, a trifluoromethyl group, a heterocyclic group, a substituted phenyl group, and the like, and particularly preferably a cyano group, an alkoxycarbonyl group, and a carbamoyl group. Group, alkylsulfonyl group,
An arylsulfonyl group, an acyl group, an acylthio group, an acylamino group, a thiocarbonyl group, a formyl group, an imino group, an imino group substituted with an N atom, a heterocyclic group, or a phenyl group substituted with any electron-withdrawing group; is there. X
It is also preferable that Y and Y combine with each other to form a non-aromatic carbon ring or a non-aromatic hetero ring. At this time, the formed ring structure is preferably a 5- to 7-membered ring,
The total carbon number is preferably 1 to 40, more preferably 3 to 30. X and Y forming a cyclic structure are preferably an acyl group, a carbamoyl group, an oxycarbonyl group, a thiocarbonyl group, a sulfonyl group, an imino group, an imino group substituted by an N atom, an acylamino group, a carbonylthio group, and the like.

In the formula (3), A and B are each independently
Represents an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic thio group, a heterocyclic oxy group, or a heterocyclic amino group, which are bonded to each other to form a cyclic structure. You may. In the formula (3), the groups represented by A and B preferably have a total carbon number of 1 to 40, more preferably a total carbon number of 1 to 40.
To 30 and may further have a substituent.
In the formula (3), A and B more preferably combine with each other to form a cyclic structure. The cyclic structure formed at this time is preferably a 5- to 7-membered non-aromatic hetero ring, and preferably has a total carbon number of 1 to 40, and more preferably 3 to 30. In this case, an example in which A and B are linked (-AB
-), For example, -O- (CH ₂ ) ₂ -O-, -O- (CH ₂ ) ₃ -O-,-
S- (CH ₂ ) ₂ -S-, -S- (CH ₂ ) ₃ -S-, -S-ph-S-, -N (CH ₃ )-(CH ₂ )
₂ -O-, -N (CH ₃ )-(CH ₂ ) ₂ -S-, -O- (CH ₂ ) ₂ -S-, -O- (CH ₂ ) ₃ -S
-, -N (CH ₃ ) -ph-O-, -N (CH ₃ ) -ph-S-, -N (ph)-(CH ₂ ) ₂ -S-
And so on.

Formulas (1) to (1) which can be used in the present invention
The compound represented by (3) may have a built-in adsorptive group that adsorbs to silver halide. Examples of such an adsorptive group include U.S. Pat. JP-A-59-19523
No. 3, No. 59-200231, No. 59-20
Nos. 1045, 59-201046, 59
JP-201047, JP-A-59-201048,
JP-A-59-201049, JP-A-61-17073.
No. 3, No. 61-270744, No. 62-94
No. 8, No. 63-234244, No. 63-23
The groups described in JP-A Nos. 4245 and 63-234246 are exemplified. These adsorbing groups to silver halide may be precursors. Examples of such a precursor include groups described in JP-A-2-285344.

Formulas (1) to (1) which can be used in the present invention
The compound represented by (3) may have a ballast group or a polymer commonly used in immobile photographic additives such as couplers incorporated therein. Particularly, those having a ballast group incorporated therein are preferred examples of the present invention.
One. The ballast group is a group having a carbon number of 8 or more and relatively inactive to photographic properties. You can choose from. As a polymer,
For example, those described in JP-A-1-100530 can be mentioned. Formulas (1) to (3) that can be used in the present invention
The compound represented by is a cationic group (specifically, a group containing a quaternary ammonium group, a nitrogen-containing heterocyclic group containing a quaternized nitrogen atom, etc.), an ethyleneoxy group, A group containing a repeating unit of a propyleneoxy group, an (alkyl, aryl, or heterocyclic) thio group,
Alternatively, it may contain a dissociable group that can be dissociated by a base (carboxy group, sulfo group, acylsulfamoyl group, carbamoylsulfamoyl group, etc.). Particularly, a group containing a group containing a repeating unit of an ethyleneoxy group or a propyleneoxy group or a group containing an (alkyl, aryl, or heterocyclic) thio group is one of preferred examples of the present invention. Specific examples of these groups include, for example, JP-A-7-234471 and JP-A-5-3334.
No. 66, JP-A-6-19032, JP-A-6-19032.
19031, JP-A-5-45761, U.S. Pat. No. 4,994,365, U.S. Pat.
No. 04, JP-A-3-259240, JP-A-7-5610, JP-A-7-244348,
Compounds described in German Patent No. 4006032 and the like can be mentioned.

Specific examples of the compounds represented by the formulas (1) to (3) are shown below. However, the compounds that can be used in the present invention include:
It is not limited to the following compounds.

[0054]

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[0055]

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[0056]

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[0057]

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The compounds represented by the formulas (1) to (3) can be prepared from water or a suitable organic solvent such as alcohols (eg, methanol, ethanol, propanol, fluorinated alcohols) and ketones (eg, acetone). , Methyl ethyl ketone), dimethylformamide, dimethylsulfoxide, methylcellosolve and the like. Also, by an already well-known emulsification dispersion method, dissolution is performed using an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone, and mechanically emulsified and dispersed. An object can be prepared and used. Alternatively, a compound powder can be dispersed in a suitable solvent such as water by a ball mill, a colloid mill, or ultrasonic waves by a method known as a solid dispersion method and used.

The compounds represented by the formulas (1) to (3) may be added to the layer on the image forming layer side of the support, that is, to the image forming layer or any other layer. It is preferably added to a layer or a layer adjacent thereto. Equation (1)-Equation
The amount of the compound represented by (3) is 1 × with respect to 1 mol of silver.
It is preferably 10 ^-6 to 1 mol, more preferably 1 × 10 ^{-5 to} 5 × 10 ^-1 mol, and most preferably 2 × 10 ^-5 to 2 × 10 ^-1 mol. The compounds represented by the formulas (1) to (3) can be easily synthesized by known methods. For example, US Pat. No. 5,545,515 and US Pat.
39, U.S. Pat. No. 5,654,130, International Publication WO 97/34196,
The compound can be synthesized with reference to the methods described in Japanese Patent Application No. 309813 and Japanese Patent Application No. 9-272002.

The compounds represented by the formulas (1) to (3) may be used alone or in combination of two or more. In addition to the above, US Pat. No. 5,545,515, US Pat. No. 5,635,339, US Pat.
No. 30, the specification of International Publication No. WO97 / 34196, the compounds described in U.S. Pat. No. 5,686,228, or the specifications of Japanese Patent Application Nos. 9-228881, 9-273935, 9 Hei 9-30981
3, Japanese Patent Application No. 9-296174, Japanese Patent Application No. 9-282564, Japanese Patent Application No. 9-272002, Japanese Patent Application No. 9-272003, Japanese Patent Application No. 9-1997.
You may use together the compound described in 332388 specification. In the present invention, the nucleating agent and the hydrazine derivative may be used in combination. In that case, the following hydrazine derivatives are preferably used. The hydrazine derivative preferably used in the present invention can also be synthesized by various methods described in the following patent specifications.

Compounds represented by (Chemical Formula 1) described in JP-B-6-77138, specifically, compounds described on pages 3 and 4 of the same publication. It is a compound represented by the general formula (I) described in JP-B-6-93082, specifically, the compound described in pages 8 to 18 of the publication.
~ 38 compounds. Compounds represented by formulas (4), (5) and (6) described in JP-A-6-230497, specifically, compound 4 described on pages 25 and 26 of the same publication -1
-Compounds 4-10, compounds 5-1 to 5-42 described on pages 28 to 36,
And compounds 6-1 to 6-7 described on pages 39 and 40. Compounds represented by general formulas (1) and (2) described in JP-A-6-289520, specifically, compounds 1-1) to 1-1-1 described on pages 5 to 7 of the same publication. 17) and 2-1). JP-A-6-31
Compounds represented by (Chemical Formula 2) and (Chemical Formula 3) described in JP-A-3936, specifically, compounds described on pages 6 to 19 of the same publication.
Compounds represented by (Chemical Formula 1) described in JP-A-6-313951, specifically, compounds described on pages 3 to 5 of the same. Compounds represented by formula (I) described in JP-A-7-5610, specifically, compounds I-1 to I-5 described on pages 5 to 10 of the same publication
I-38. Compounds represented by general formula (II) described in JP-A-7-77783, specifically, compounds II-1 to II-102 described on pages 10 to 27 of the same. A compound represented by the general formula (H) and the general formula (Ha) described in JP-A-7-104426,
Specifically, compounds H-1 to H-4 described on pages 8 to 15 of the publication
Four. A compound characterized by having an anionic group or a nonionic group forming an intramolecular hydrogen bond with a hydrogen atom of hydrazine in the vicinity of a hydrazine group described in JP-A-9-22082, and particularly a compound represented by the general formula (A) ), General formula (B), general formula (C), general formula (D), general formula (E),
Compounds represented by the general formula (F), specifically, compounds N-1 to N-30 described in the publication. Compounds represented by the general formula (1) described in JP-A-9-22082, specifically, compounds D-1 to D-55 described in the same. March 22, 1991
Various hydrazine derivatives described on pages 25 to 34 of "Known Techniques (pages 1 to 207)" (published by Aztec Co., Ltd.) JP-A-62-8
Compounds D-2 and D-39 of JP-A-6354 (pages 6 to 7).

The hydrazine derivative preferably used in the present invention includes a suitable organic solvent such as alcohols (eg, methanol, ethanol, propanol, fluorinated alcohol, etc.), ketones (eg, acetone, methyl ethyl ketone, etc.), dimethylformamide, It can be used by dissolving it in dimethyl sulfoxide, methyl cellosolve or the like. Also, by an already well-known emulsification dispersion method, dissolution is performed using an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate, and an auxiliary solvent such as ethyl acetate or cyclohexanone, and mechanically emulsified and dispersed. An object can be prepared and used. Alternatively, a powder of a hydrazine derivative can be dispersed in water by a ball mill, a colloid mill, or an ultrasonic wave by a method known as a solid dispersion method and used.

The hydrazine derivative preferably used in the present invention may be added to any one of the image forming layer and the other binder layer on the image forming layer side with respect to the support.
It is preferable to add to the image forming layer or the binder layer adjacent thereto. The amount of the hydrazine derivative added is
1 × 10 ⁻⁶ to 1 × 10 ⁻² mol is preferable for 1 mol of silver, and 1 × 10
^{-5 to} 5 × 10 ^-3 mol is more preferred, and 2 × 10 ^{-5 to} 5 × 10 ^-3 mol is most preferred. In the present invention, for forming a super-high contrast image, a high contrast accelerator can be used in combination with the nucleating agent. For example, amine compounds described in U.S. Pat. No. 5,545,505, specifically AM-1 to AM
-5, hydroxamic acids described in U.S. Pat. No. 5,545,507, specifically HA-1 to HA-11,
Acrylonitrile described in U.S. Pat. No. 5,545,507, specifically CN-1 to CN-13, hydrazine compound described in U.S. Pat. No. 5,558,983, specifically CA-1 to CA-6, JP-A-9-2
Onium salts described in JP-A-97368, specifically A-1 to A-42, B-1 to B-27, C-1 to C-1
4 or the like can be used.

A non-light-sensitive silver salt, a light-sensitive silver halide and
In a photothermographic material having a binder, formic acid is present.
Or formate is a strong fogging substance. In the present invention,
Image formation containing photosensitive silver halide in developed photosensitive material
1 mole of silver formic acid or formate on the layer side
5 mmol or less, and even 1 mmol or less
Is preferred. The heat-developable image recording material of the present invention contains
Acid or its salt formed by hydration of diphosphorus
It is preferable to use it. Diphosphorus pentoxide hydrates
Possible acids or salts thereof include metaphosphoric acid (salt),
Loric acid (salt), orthophosphoric acid (salt), triphosphoric acid
(Salt), tetraphosphate (salt), hexametaphosphate (salt), etc.
It is. Particularly preferably used diphosphorus pentoxide is hydrated
Orthophosphoric acid (salt),
Hexametaphosphoric acid (salt).
Sodium orthophosphate, sodium dihydrogen orthophosphate
System, sodium hexametaphosphate, hexametaphosphate
And ammonium. Preferably used in the present invention
Diphosphorus pentoxide that can be hydrated
The image shows that the salt of
To the forming layer or the binder layer adjacent to it.
You. Use of acid or its salt formed by hydration of diphosphorus pentoxide
Dose (image recording material 1m^Two Per application)
The desired amount is acceptable according to the performance such as degree and fog,
0.1-500mg / m^TwoIs preferably 0.5 to 100 m
g / m^TwoIs more preferred.

The heat-developable image recording material of the present invention contains a reducing agent for an 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 preferably contained in an amount of 5 to 50 mol%, more preferably 10 to 40 mol%, per 1 mol of silver on the surface having the image forming layer. The layer to which the reducing agent is added may be any layer on the side having the image forming layer. When it is added to a layer other than the image forming layer, it is preferable to use a reducing agent in an amount of 10 to 50 mol% based on 1 mol of silver. Further, the reducing agent may be a so-called precursor which is derivatized so as to have a function effectively only during development.

In a photothermographic material using an organic silver salt, a wide range of reducing agents are disclosed in JP-A-46-6074 and JP-A-47-1238.
No. 47-33621, No. 49-46427, No. 49-1
No. 15540, No. 50-14334, No. 50-36110,
No. 50-147711, No. 51-32632, No. 51-1023721
JP-A-51-32324, JP-A-51-51933 and JP-A-52-8
No. 4727, No. 55-108654, No. 56-146133,
No. 57-82828, No. 57-82829, JP-A-6-3793, U.S. Pat.No. 3,679,426, No. 3,751,252, No. 3,751,255, No. 3,761,270, No.
3,782,949, 3,839,048, 3,928,68
No. 6, specification No. 5,464, 738, German Patent No. 2321328
And EP No. 692732.
For example, amide oximes such as phenylamidooxime, 2-thienylamidooxime and p-phenoxyphenylamidooxime; azines such as 4-hydroxy-3,5-dimethoxybenzaldehydeazine; 2,2'-bis (hydroxymethyl) propionyl a combination of an aliphatic carboxylic acid aryl hydrazide such as a combination of -β-phenylhydrazine and ascorbic acid with ascorbic acid; a combination of polyhydroxybenzene with hydroxylamine, reductone and / or hydrazine (for example, hydroquinone, bis (ethoxy) Ethyl) hydroxylamine,
Such as a combination of piperidinohexose reductone or formyl-4-methylphenylhydrazine); hydroxamic acids such as phenylhydroxamic acid, p-hydroxyphenylhydroxamic acid and β-alinine hydroxamic acid;
Combinations of azine and sulfonamidophenol (e.g., phenothiazine and 2,6-dichloro-4-benzenesulfonamidophenol, etc.); α such as ethyl-α-cyano-2-methylphenylacetate, ethyl-α-cyanophenylacetate -Cyanophenylacetic acid derivatives; 2,2'-dihydroxy-1,1'-binaphthyl, 6,6'-dibromo-2,2'-dihydroxy-1,1'-binaphthyl and bis (2-hydroxy-1-naphthyl ) Bis-β-naphthol as exemplified by methane; bis-β-naphthol and 1,3-dihydroxybenzene derivatives (eg, 2,4-dihydroxybenzophenone or
2 ', 4'-dihydroxyacetophenone); 3-
5-pyrazolones, such as methyl-1-phenyl-5-pyrazolone; reductones as exemplified by dimethylaminohexose reductone, anhydrodihydroaminohexose reductone and anhydrodihydropiperidone hexose reductone; 2 Sulfonamide phenol reducing agents such as 2,6-dichloro-4-benzenesulfonamidophenol and p-benzenesulfonamidophenol; 2-phenylindane-1,3-dione; 2,2-dimethyl-7-t-butyl- Chromans such as 6-hydroxychroman; 1,4-dihydropyridines such as 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine; bisphenols (for example, bis (2-hydroxy-3-t-butyl) -5-methylphenyl) methane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4,4-ethylidene-bis (2-t-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.); ascorbin Acid derivatives (eg, 1-ascorbyl palmitate, ascorbyl stearate, etc.); and aldehydes and ketones such as benzyl and biacetyl;
Pyrazolidone and certain indan-1,3-diones; chromanol (such as tocopherol). Particularly preferred reducing agents are bisphenol and chromanol.

In the present invention, the reducing agent may be added by any method such as an aqueous solution, an organic solvent solution, powder, solid fine particle dispersion, and emulsified dispersion. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used. In the present invention, a phenol derivative represented by the formula (A) described in Japanese Patent Application No. 11-73951 is preferably used as a development accelerator. Formula (A)
The phenol derivative represented by represents a strong development promoting effect when used in combination with the above reducing agent. Specifically, A-1 to A-54 described in the same specification are preferably used.
The phenol derivative represented by the formula (A) is preferably used in the range of 0.01 mol% to 100 mol%, more preferably 0.1 mol% to 20 mol%, based on the reducing agent. Is preferably performed. The phenol derivative represented by the formula (A) is a layer on the image forming layer side with respect to the support,
That is, it may be added to the image forming layer or any other layer on the layer side, but is preferably added to the layer containing the reducing agent. The phenol derivative represented by the formula (A) may be added by any method such as an aqueous solution, an organic solvent solution, powder, solid fine particle dispersion, and emulsified dispersion. The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

When an additive known as a "toning agent" for improving an image is contained, the optical density may be increased. The toning agent may also be advantageous in forming a black silver image. The toning agent is preferably contained in an amount of 0.1 to 50% mol, more preferably 0.5 to 20% mol, per mol of silver on the surface having the image forming layer. Further, the color tone agent may be a so-called precursor which is derivatized so as to have a function effectively only during development. In a photothermographic material using an organic silver salt, a wide range of color toning agents are disclosed in JP-A-46-6077, JP-A-47-10282, JP-A-49-10282.
No. 5019, No. 49-5020, No. 49-91215, No. 4
No. 9-91215, No. 50-2524, No. 50-32927,
No. 50-67132, No. 50-67641, No. 50-114217, No. 51-3223, No. 51-27923, No. 52-1478
No. 8, No. 52-99813, No. 53-1020, No. 53-7
No. 6020, No. 54-156524, No. 54-156525,
No. 61-183642, JP-A-4-56848, JP-B-49-1
No. 0727, 54-20333, U.S. Pat.No.3,080,254
No. 3,446,648, No. 3,782,941, No. 4,123,282, No. 4,510,236,
It is disclosed in British Patent No. 1380795 and Belgian Patent No. 841910. Examples of toning agents are phthalimide and N-hydroxyphthalimide; succinimide, pyrazoline-5
-One, and quinazolinone, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and
Cyclic imides such as 2,4-thiazolidinedione; naphthalimides (eg, N-hydroxy-1,8-naphthalimide);
Cobalt complexes (eg, cobalt hexamine trifluoroacetate); 3-mercapto-1,2,4-triazole,
4-dimercaptopyrimidine, 3-mercapto-4,5-diphenyl-1,2,4-triazole and 2,5-dimercapto-1,3,
Mercaptans exemplified by 4-thiadiazole; N- (aminomethyl) aryldicarboximide, (for example, (N, N
-Dimethylaminomethyl) phthalimide and N, N- (dimethylaminomethyl) -naphthalene-2,3-dicarboximide); and blocked pyrazoles, isothiuronium derivatives, and certain photobleaches (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-chlorophthalazinone, 5,7-
Derivatives such as dimethoxyphthalazinone and 2,3-dihydro-1,4-phthalazinedione; phthalazinone and phthalic acid derivatives (eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride) Phthalazine, phthalazine derivatives (for example, 4- (1-
Naphthyl) phthalazine, 6-chlorophthalazine, 5,7-dimethoxyphthalazine, 6-iso-butylphthalazine, 6-tert-
Butylphthalazine, 5,7-dimethylphthalazine, and 2,
Derivatives such as 3-dihydrophthalazine) or metal salts; phthalazine and its derivatives and phthalic acid derivatives
(Eg, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride, etc.); quinazolinedione, benzoxazine or naphthoxazine derivatives; silver halide in situ as well as color tone modifier Rhodium complex that also functions as a source of halide ions for formation, such as hexachlororhodium
(III) ammonium, rhodium bromide, rhodium nitrate and potassium hexachlororhodate (III) and the like; inorganic peroxides and persulfates, such as ammonium disulfide and hydrogen peroxide; 1,3-benzoxazine- 2,4-
Benzoxazine-2,4-diones such as dione, 8-methyl-1,3-benzoxazine-2,4-dione and 6-nitro-1,3-benzoxazine-2,4-dione; pyrimidine and asymmetric -Triazines (e.g., 2,4-dihydroxypyrimidine,
2-hydroxy-4-aminopyrimidine, etc.), azauracil, and tetraazapentalene derivatives (e.g., 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).

In the present invention, as a color tone agent, Japanese Patent Application No.
A phthalazine derivative represented by the general formula (F) described in JP 13487 is preferably used. Specifically, when a toning agent is used in the present invention in which A-1 to A-10 are preferably used as described in the same specification, it may be added by any method such as a solution, a powder, and a solid fine particle dispersion. . The dispersion of the solid fine particles is carried out by a known means for making fine (for example, a ball mill, a vibration ball mill, a sand mill, a colloid mill, a jet mill, a roller mill, etc.). When dispersing the solid fine particles, a dispersing aid may be used.

The surface pH of the heat-developable image recording material of the present invention before the heat development treatment is preferably 6.0 or less, more preferably 5.5 or less. The lower limit is not particularly limited, but is about 3. The adjustment of the film surface pH is preferably performed using an organic acid such as a phthalic acid derivative, a nonvolatile acid such as sulfuric acid, or a volatile base such as ammonia from the viewpoint of reducing the film surface pH. In particular, ammonia is preferable in achieving a low film surface pH since ammonia is easily volatilized and can be removed before the application step and the heat development. The method for measuring the film surface pH is described in [0123] of Japanese Patent Application No. 11-87297. In the heat-developable image recording material of the present invention, the silver halide emulsion or / and organic silver salt is further protected against the formation of additional fog by antifoggants, stabilizers and stabilizer precursors,
It can be stabilized against a decrease in sensitivity during stock storage. Suitable antifoggants, stabilizers and stabilizer precursors which can be used alone or in combination are the thiazonium salts described in U.S. Pat.Nos. 2,131,038 and 2,694,716, U.S. Pat.No. 2,886,437. No. 2,444,605, mercury salts described in U.S. Pat.No. 2,728,663, urazole described in U.S. Pat.No. 3,287,135, sulfocatechol described in U.S. Pat.No. 3,235,652 ,
Oxime described in British Patent No. 623,448, nitrone, nitroindazole, polyvalent metal salt described in U.S. Pat.No. 2,839,405, thiuronium salt described in U.S. Pat.No. 3,220,839, and U.S. Pat.No. 2,566,263 No. 4,597,915, palladium, platinum and gold salts, U.S. Pat.Nos. 4,108,665 and 4,442,202, halogen-substituted organic compounds described in U.S. Pat.No. 4,128,557 and U.S. Pat. 4,13
No. 7,079, No. 4,138,365 and No. 4,45
No. 9,350, triazine and U.S. Pat.
And the phosphorus compounds described in 4,411,985.

The heat-developable image recording material of the present invention may contain benzoic acids for the purpose of increasing the sensitivity and preventing fogging. The benzoic acid used in the present invention may be any benzoic acid derivative.
No. 4,784,939, No. 4,152,160, JP-A-9
Compounds described in JP-A-3298663, JP-A-9-329864, and JP-A-9-281637 are exemplified. The benzoic acid may be added to any part of the image recording material, but it is preferably added to the layer having the photosensitive layer, more preferably to the organic silver salt-containing layer. The benzoic acid may be added in any step of the preparation of the coating solution, and when it is added to the organic silver salt-containing layer, any step from the preparation of the organic silver salt to the preparation of the coating solution may be performed. To just before application. The benzoic acid may be added by any method such as powder, solution, and fine particle dispersion. Further, it may be added as a solution mixed with other additives such as a sensitizing dye, a reducing agent, and a color tone agent. The benzoic acid may be added in any amount, but not less than 1 × 10 ^-6 mol per mol of silver.
Mol or less, more preferably 1 × 10 ⁻³ mol or more and 0.5 mol or less.

Although not required to practice the present invention,
It may be advantageous to add mercury (II) salts as antifoggants to the emulsion layers. Preferred mercury (II) salts for this purpose are
Mercury acetate and mercury bromide. The amount of mercury used in the present invention is preferably 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol, more preferably 1 × 10 ⁻³ mol, per mol of the coated silver.
^-8 mol to 1 × 10 ^-4 mol. Antifoggants particularly preferably used in the present invention are organic halides, for example, JP-A Nos. 50-119624, 50-120328, 51-121332, 54-58022 and 54-58022. 56-7054
No. 3, No. 56-99335, No. 59-90842, No. 61-
No. 129642, No. 62-129845, No. 6-208191, No. 7-5621, No. 7-2781, No. 8-15809, U.S. Pat.No. 5,340,712, 5,369,000 And the compounds disclosed in US Pat. No. 5,464,737. A hydrophilic organic halide represented by the formula (P) described in Japanese Patent Application No. 11-87297 is preferably used as an antifoggant. Specifically, (P-1) to (P-118) described in the same specification are preferably used. The addition amount of the organic halide is 1 mol of Ag
In terms of mol (mol / molAg), preferably 1 ×
10 ^{-5 to 2} mol / mol Ag, more preferably 5 × 10 ^-5 to 1
mol / molAg, more preferably 1 × 10 ^{-4 to} 5 × 10 ^-1
mol / molAg. These may be used alone or in combination of two or more.

A salicylic acid derivative represented by the formula (Z) described in Japanese Patent Application No. 11-87297 is preferably used as an antifoggant. Specifically, (A-1) to (A-60) described in the same specification are preferably used. The amount of the salicylic acid derivative represented by the formula (Z) is:
In terms of mol amount per mol of Ag (mol / molAg), it is preferably 1 × 10 ^{−5 to} 5 × 10 ⁻¹ mol / molAg, more preferably 5 × 10 ⁻⁵ to 1 × 10 ⁻¹ mol / molAg, and still more preferably. Is 1 × 10 ^{−4 to} 5 × 10 ⁻² mol / mol Ag. These may be used alone or in combination of two or more. Antifoggants used in the present invention are water or a suitable organic solvent such as alcohols (e.g., methanol, ethanol, propanol, fluorinated alcohols, etc.), ketones (e.g., acetone, methyl ethyl ketone, etc.),
It can be used by dissolving in dimethylformamide, dimethylsulfoxide, methylcellosolve and the like. Also,
By an already well-known emulsification dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or diethyl phthalate is dissolved using an auxiliary solvent such as ethyl acetate or cyclohexanone, and the emulsified dispersion is mechanically dispersed. It can be manufactured and used. Alternatively, by a method known as a solid dispersion method, the powder is ball milled in water, a colloid mill,
It can be dispersed and used by using a sand grinder mill, Menton-Gaulin, microfluidizer, or ultrasonic wave.

The antifoggant may be added to the layer on the image forming layer side with respect to the support, that is, to the image forming layer or any other layer on the layer side. It is preferable to add. The image forming layer is a layer containing a reducible silver salt (organic silver salt), and is preferably a photosensitive layer further containing a photosensitive silver halide. The heat-developable image recording material of the present invention includes a mercapto compound, a disulfide compound, and a thione compound for controlling development by suppressing or accelerating development, improving spectral sensitization efficiency, and improving storage stability before and after development. Compounds can be included. When a mercapto compound is used in the present invention, it may have any structure, but is preferably a compound represented by Ar-SM or Ar-SS-Ar. Wherein M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic or fused aromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms. Preferably, the heteroaromatic ring is benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole, thiadiazole, tetrazole, triazine, pyrimidine, pyridazine , Pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, halogens (e.g., Br and Cl), hydroxy, amino, carboxy,
Alkyl (eg one or more carbon atoms, preferably 1
Having 4 to 4 carbon atoms), alkoxy (e.g.,
It may have a substituent selected from the group consisting of one or more carbon atoms, preferably those having 1 to 4 carbon atoms) and aryl (which may have a substituent). As mercapto-substituted heteroaromatic compounds, 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-imidazolethiol, 2-mercaptoimidazole, 1-ethyl-2-mercaptobenzimidazole, 2
-Mercaptoquinoline, 8-mercaptopurine, 2-mercapto-4 (3H) -quinazolinone, 7-trifluoromethyl-4-quinolinethiol, 2,3,5,6-tetrachloro-4-pyridinethiol, 4-amino -6-Hydroxy-2-mercaptopyrimidine monohydrate, 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazole, 4-hydrocyanic-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, sodium 3- (5-mercaptotetrazole) -benzenesulfonate, N-methyl-N '-[3- (5-mercaptotetrazolyl) phenyl] urea, 2-mercapto-4-phenyl Oxazole and the like can be mentioned, but the present invention is not limited to these. The addition amount of these mercapto compounds is preferably in the range of 0.0001 to 1.0 mol per mol of silver in the emulsion layer, and more preferably 0.001 to 0.3 mol per mol of silver.

The binder used in the heat-developable image recording material of the present invention is preferably a polymer latex described below. At least one of the image forming layers of the heat-developable image recording material of the present invention is preferably an image forming layer using the polymer latex described below as 50% by weight or more of the total binder (hereinafter, this image forming layer is referred to as `` The polymer latex used in the image forming layer of the invention and the binder is referred to as the polymer latex used in the invention.) Further, the polymer latex may be used not only for the image forming layer, but also for the protective layer and the back layer.In particular, when the heat-developable image recording material of the present invention is used for printing in which dimensional change is a problem, the protective layer or It is preferable to use a polymer latex also for the back layer. However, the "polymer latex" referred to here is a water-insoluble hydrophobic polymer dispersed as fine particles in a water-soluble dispersion medium. The dispersion state is such that the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or partially dispersed in polymer molecules and molecular chains themselves are molecularly dispersed. Any of them may be used. The polymer latex used in the present invention is described in "Synthetic Resin Emulsion" (edited by Tadashi Okuda and Hiroshi Inagaki, published by the Society of Polymer Publishing (1978)), "Application of Synthetic Latex (edited by Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, Keiji Kasahara) ,
Published by The Society of Polymer Publishing (1993)), `` Synthesis of Synthetic Latex ''
(Souichi Muroi, published by Kobunshi Kankokai (1970)). The average particle size of the dispersed particles is preferably in the range of 1 to 50,000 nm, more preferably about 5 to 1000 nm. The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution.

The polymer latex used in the present invention may be a so-called core / shell type latex other than a polymer latex having a normal uniform structure. In this case, it may be preferable to change the glass transition temperature of the core and the shell. The glass transition temperature (Tg) of the polymer latex preferably used as a binder in the heat-developable image recording material of the present invention is different for the protective layer, the back layer and the image forming layer. In the image forming layer, the temperature is preferably -30 to 40 ° C. in order to promote diffusion of the photographically useful material during thermal development. When used for the protective layer or the back layer, a glass transition temperature of 25 to 70 ° C. is preferable for contacting various devices. Minimum film forming temperature of polymer latex used in the present invention
(MFT) is preferably -30 ° C to 90 ° C, more preferably about 0 ° C to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. A film-forming aid is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of a polymer latex, also called a plasticizer, and is described in, for example, `` Synthesis of Synthetic Latex (Souichi Muroi, published by Kobunshi Kankokai (1970) )"It is described in.

The polymer used in the polymer latex used in the present invention includes acrylic resin, vinyl acetate resin, polyester resin, polyurethane resin, rubber resin, vinyl chloride resin, vinylidene chloride resin, polyolefin resin, or a copolymer thereof. and so on. Whether the polymer is a linear polymer or a branched polymer,
Further, a crosslinked polymer may be used. The polymer may be a so-called homopolymer in which a single monomer is polymerized, or a copolymer in which two or more monomers are polymerized. In the case of a copolymer, it may be a random copolymer or a block copolymer. The molecular weight of the polymer is preferably from 5000 to 100000, more preferably from about 10,000 to 100,000 in number average molecular weight. If the molecular weight is too small, the mechanical strength of the image forming layer is insufficient, and if it is too large, the film-forming property is poor, which is not preferable. Specific examples of the polymer latex used as a binder for the image forming layer of the heat-developable image recording material of the present invention include the following. Latex of methyl methacrylate / ethyl acrylate / methacrylic acid copolymer, latex of methyl methacrylate / 2-ethylhexyl acrylate / styrene / acrylic acid copolymer, latex of styrene / butadiene / acrylic acid copolymer, latex of styrene / butadiene / divinylbenzene / methacrylic acid copolymer Latex of methyl methacrylate / vinyl chloride / acrylic acid copolymer, latex of vinylidene chloride / ethyl acrylate / acrylonitrile / methacrylic acid copolymer, and the like. Such polymers are also commercially available,
The following polymers can be used. For example, as an example of an acrylic resin, Sebian A-4635,46583,4601 (all manufactured by Daicel Chemical Industries, Ltd.), Nipol Lx811,814,821,82
Polyester resins such as 0, 857 (all manufactured by Nippon Zeon Co., Ltd.) include FINETEX ES650, 611, 675, 850 (all manufactured by Dainippon Ink and Chemicals, Inc.), WD-size, WMS (all manufactured by Eastman Chemical Co., Ltd.) HYDRAN as polyurethane resin
LACSTAR 7310K, 3307B, 4700 are rubber-based resins such as AP10, 20, 30, 40 (all manufactured by Dainippon Ink and Chemicals, Inc.)
H, 7132C (all manufactured by Dainippon Ink and Chemicals, Inc.), Nipol Lx41
6, 410, 438C, 2507, (all made by Nippon Zeon Co., Ltd.)
Examples of vinyl chloride resins include G351 and G576 (both manufactured by Nippon Zeon Co., Ltd.). Examples of vinylidene chloride resins include L502 and L51.
3 (all manufactured by Asahi Kasei Corporation), Aron D7020, D504, D507
Examples of olefin resins include Chemipearl S120 and SA100 (both manufactured by Mitsui Petrochemical Co., Ltd.). These polymers may be used alone or as a blend of two or more as necessary.

In the image forming layer in the present invention, the above-mentioned polymer latex is preferably used as 50% by weight or more of the whole binder, and more preferably 70% by weight or more of the above-mentioned polymer latex. In the image forming layer in the present invention, if necessary, 50% by weight of all binders
%, A hydrophilic polymer such as gelatin, polyvinyl alcohol, methylcellulose, hydroxypropylcellulose, carboxymethylcellulose, or hydroxypropylmethylcellulose may be added. The amount of these hydrophilic polymers to be added is preferably 30% by weight or less, more preferably 15% by weight or less of the total binder in the image forming layer. The image forming layer in the invention is preferably prepared by applying an aqueous coating solution and then drying. However, the term “aqueous” as used herein means that 60% by weight or more of the solvent (dispersion medium) of the coating liquid is water. As components other than water of the coating solution, water-miscible organic solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, and ethyl acetate can be used. Specific examples of the solvent composition include the following. Water / methanol = 90/10, water / methanol =
70/30, water / ethanol = 90/10, water / isopropanol = 90/10, water / dimethylformamide = 95/5, water / methanol / dimethylformamide = 80/15/5, water / methanol / dimethylformamide = 90 / 5/5. (However, numbers represent weight%.)

Further, as binders for the protective layer, paragraphs [0025] to [0025] of Japanese Patent Application No. 11-6872 can be used.
A combination of polymer latexes having different I / O values obtained by dividing the inorganic value based on the organic conceptual diagram described in [0029] by the organic value can be preferably used. Each layer has a first polymer latex into which a functional group described in paragraphs [0023] to [0041] of Japanese Patent Application No. 10-199626 is introduced, and a functional group capable of reacting with the first polymer latex. It can also be formed using a crosslinking agent having a group and / or a second 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, and an oxazolinyl group.As the crosslinking agent, an epoxy compound, an isocyanate compound, a blocked isocyanate compound, a methylol compound, Compound,
It is selected from a carboxyl compound, an amino compound, an ethyleneimine compound, an aldehyde compound, a halogen compound and the like. As specific examples of the crosslinking agent, an isocyanate compound:
Hexamethylene isocyanate, duranate WB40
-80D, WX-1741 (manufactured by Asahi Kasei Kogyo Co., Ltd.), Baihijur 3100 (Sumitomo Bayer Urethane Co., Ltd.)
Manufactured), Takenate WD725 (Takeda Pharmaceutical Co., Ltd.)
Aquanate 100, 200 (manufactured by Nippon Polyurethane Co., Ltd.), water-dispersible polyisocyanate and amino compound described in JP-A-9-160172: Sumitex Resin M-3 (manufactured by Sumitomo Chemical Co., Ltd.) ), Epoxy compounds: Denacol EX-614B (manufactured by Nagase Kasei Kogyo Co., Ltd.), halogen compounds: sodium 2,4-dichloro-6-hydroxy-1,3,5-triazine, and the like.

The total amount of the binder for the image forming layer in the present invention is 0.2 to 30 g / m ² , more preferably 1.0 to 1 g / m ² .
A range of 5 g / m ² is preferred. The total amount of the binder for the protective layer in the present invention is preferably in the range of 0.2 to 10.0 g / m ² , more preferably 0.5 to 6.0 g / m ² . The total amount of the binder for the back layer in the invention is from 0.01 to 10.
0 g / m ^2, more 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 image forming layer has two or more layers, it is preferable to use a polymer latex as a binder for all the layers. Further, the protective layer is a layer provided on the image forming layer, and may have two or more layers.
Preferably, a polymer latex is used for the layer, especially the outermost protective layer. The back layer is a layer provided on the undercoat layer on the back surface of the support, and there may be two or more layers. However, it is preferable to use a polymer latex for at least one layer, particularly the outermost back layer. A crosslinking agent for crosslinking, a surfactant for improving coating properties, and the like may be added to the image forming layer in the invention.

There are no particular restrictions on the type of slip agent used in the present invention, and any compound may be used as long as it reduces the coefficient of friction on the surface of the object when it is present on the surface of the object, compared to when it is not present. Examples of the slip agent used in the present invention include paragraph [006] of JP-A-11-84573.
1] to [0064], and the compounds described in Paragraph Nos. [0049] to [0062] of Japanese Patent Application No. 11-106881. Specific examples of preferred slip agents include Cellsol 524 (main component carnauba wax), Polylon A, 3
93, H-481 (main component polyethylene wax), Himicron G-110 (main component ethylene bisstearic acid amide), Himicron G-270 (main component stearic acid amide) (all manufactured by Chukyo Yushi Co., Ltd.), or the like compound represented by _{W-1 C 16 H 33 -O} -SO 3 Na W-2 C 18 H 37 -O-SO 3 Na. The amount of the slip agent used is 0.1 to 50% by weight, preferably 0.5 to 30% by weight, based on the amount of the binder in the added layer.

When the heat-developable image-recording material of the present invention is subjected to heat-development processing, the preheated portions as described in Japanese Patent Application Nos. 10-346561 and 11-106881 are opposed to each other. In the case of using a heat development processing apparatus in which a heat development image recording material is transported by a roller, and the heat development processing unit transports the side having the image forming layer by driving the roller, and sliding the back surface on the opposite side to a smooth surface. The ratio of the coefficient of friction between the outermost surface layer having the image forming layer and the outermost surface layer on the back surface of the heat-developable image recording material at the development processing temperature is 1.5 or more, and the upper limit is not particularly limited. No, but around 30. Further, μb is 1.0 or less, preferably 0.8 to 0.05. This value is obtained by the following equation. Ratio of friction coefficient = dynamic friction coefficient between the roller member of the heat developing machine and the surface having the image forming layer (μe) / dynamic friction coefficient between the smooth surface member of the heat developing machine and the back surface (μb)
In the present invention, the slipperiness of the outermost surface layer on the surface having the heat-development processing machine member and the image forming layer at the heat development processing temperature and / or the opposite surface is determined by allowing the outermost surface layer to contain a slipping agent, It can be changed and adjusted.

On both sides of the support of the heat-developable image recording material of the present invention, JP-A-64-20544 and JP-A-1-201544
80537, JP-A-1-209443, JP-A-1-285939, JP-A-1-296243
JP, JP-A-2-24649, JP-A-2-24
648, JP-A-2-184844, JP-A-3-109545, JP-A-3-137637, JP-A-3-141346, JP-A-3-141
No. 347, Japanese Patent Application Laid-Open No. 4-96055, U.S. Pat. No. 4,645,731 and Japanese Patent Application Laid-Open No. 4-68344, Japanese Patent No. 25557641, P20 right column, line 20 to P3 right column, line 30; No. 221039, paragraph numbers [0020] to [0037], Japanese Patent Application No. 11-106.
No. 881, paragraphs [0063] to [0080]
It is preferable to provide an undercoat layer containing a vinylidene chloride copolymer containing at least 70% by weight of a repeating unit of the vinylidene chloride monomer described in (1).

When the amount of the vinylidene chloride monomer is less than 70% by weight, sufficient moisture-proof properties cannot be obtained, and the dimensional change over time after thermal development becomes large. Further, the vinylidene chloride copolymer preferably contains a repeating unit of a carboxyl group-containing vinyl monomer as another constituent repeating unit of the vinylidene chloride monomer. The inclusion of such a constitutional repeating unit is because the polymer (polymer) is crystallized by using only the vinyl chloride monomer, so that it is difficult to form a uniform film when the moisture-proof layer is applied, and This is because a carboxyl group-containing vinyl monomer is indispensable for stabilizing (polymer). The molecular weight of the vinylidene chloride copolymer used in the present invention is 4500 in weight average molecular weight.
It is preferably 0 or less, more preferably 10,000 or more and 45,000 or less. When the molecular weight is large, the adhesiveness between the vinylidene chloride copolymer layer and the support layer such as polyester is deteriorated.

The content of the vinylidene chloride copolymer is at least 0.3 μm as a total thickness per one side of the undercoat layer containing the vinylidene chloride copolymer, and is preferably at least 0.1 μm.
The range is 3 μm or more and 4 μm or less. The vinylidene chloride copolymer layer as the undercoat layer is preferably provided as the first undercoat layer directly provided on the support. Usually, one layer is provided on each side, but in some cases, two layers are provided. The above may be provided. When a multi-layer structure of two or more layers is used, the amount of the vinylidene chloride copolymer may be in a desired range in total. Such a layer may contain a crosslinking agent, a matting agent, and the like in addition to the vinylidene chloride copolymer.

The support may be coated with an undercoat layer using SBR, polyester, gelatin or the like as a binder, if necessary, in addition to the vinylidene chloride copolymer layer. These undercoat layers may have a multilayer structure or may be provided on one side or both sides of the support. The general thickness of the undercoat layer (per layer) is 0.01 to 5 μm, more preferably 0.05 to 1 μm. Various supports can be used for the heat-developable image recording material of the present invention. Typical supports include polyesters such as polyethylene terephthalate, polyethylene naphthalate, cellulose nitrate, cellulose esters, polyvinyl acetal, syndiotactic polystyrene, polycarbonate, paper supports coated on both sides with polyethylene, and the like. Among them, biaxially stretched polyester, particularly polyethylene terephthalate (PET), is preferable in terms of strength, dimensional stability, chemical resistance and the like. The thickness of the support is preferably 90 to 180 μm as a base thickness excluding the undercoat layer.

The support used in the heat-developable image recording material of the present invention is described in JP-A-10-48772 and JP-A-10-0.
No. 48772, JP-A-10-010676,
JP-A-10-010677, Japanese Patent Application No. 9-2251
In order to alleviate the internal strain remaining in the film at the time of biaxial stretching described in Japanese Patent Application No. 31 and Japanese Patent Application No. 9-308898, and to eliminate the heat shrinkage distortion generated during thermal development, 1
Polyester, particularly polyethylene terephthalate, which has been subjected to a heat treatment in a temperature range of 30 to 185 ° C is preferably used. 120 ° C. of the support after such heat treatment
The dimensional change rate by heating for 30 seconds is -0.0 in the vertical direction (MD).
03% to + 0.01%, lateral direction (TD) is 0 to 0.04
%.

The heat-developable image recording material of the present invention is disclosed in Japanese Patent Application Laid-Open No. H11-84573 for the purpose of reducing adhesion of dust, preventing generation of static marks, and preventing transport failure in an automatic transport step.
The antistatic effect can be achieved by using a conductive metal oxide and / or a fluorinated surfactant described in paragraphs [0040] to [0051] of JP-A No. 195/1992. As the conductive metal oxide, US Pat. No. 5,575,957, Japanese Patent Application No.
No. 041302, paragraphs [0012] to [00]
20], a needle-shaped conductive tin oxide doped with antimony, and a fibrous tin oxide doped with antimony described in JP-A-4-29134 are preferably used. The surface resistivity (surface resistivity) of the metal oxide-containing layer is 10 ¹² Ω or less, preferably 10 ¹¹ Ω or less in an atmosphere of 25 ° C. and 20% RH. Thereby, good antistatic properties can be obtained. The lower limit of the surface resistivity at this time is not particularly limited, but is usually about 10 ⁷ Ω.

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 of the outermost layer opposite to the surface, preferably both, is 2,000 seconds or less, more preferably 10 seconds. ~ 2000 seconds.
The Beck smoothness in the present invention is determined by the Japanese Industrial Standards (JI
S) It can be easily obtained according to P8119 “Smoothness test method of paper and paperboard with Beck tester” and TAPPI standard method T479. The Beck smoothness of the outermost layer having the image forming layer of the heat-developable image recording material and the outermost layer on the opposite side thereof are as described in paragraphs [0052] to [0059] of JP-A-11-84573. It can be controlled by appropriately changing the particle size and amount of the matting agent contained in the layers on both surfaces. In the present invention, the undercoat layer and / or the backing layer
-84573, paragraph numbers [0204] to [020]
8], a dye can be contained for the purpose of preventing halation as described in paragraphs [0240] to [0241] of Japanese Patent Application No. 11-106881.

The heat-developable image recording material of the present invention preferably contains a photosensitive silver halide. The photosensitive silver halide that can be used in the present invention is not particularly limited as a halogen composition, and silver chloride, silver chlorobromide, silver bromide, silver iodobromide, and silver iodochlorobromide can be used. The distribution of the halogen composition in the grains may be uniform, the halogen composition may change stepwise, or may change continuously. Further, silver halide grains having a core / shell structure can be preferably used. As the structure, core / shell particles having preferably a 2- to 5-layer structure, more preferably a 2- to 4-layer structure, can be used. A technique for localizing silver bromide on the surface of silver chloride or silver chlorobromide grains can also be preferably used.

Methods of forming photosensitive silver halide are well known in the art, for example, Research Disclosure No. 17029, June 1978, and US Pat. No. 3,700,458.
Can be used.Specifically, a photosensitive silver halide is prepared by adding a silver supply compound and a halogen supply compound to gelatin or another polymer solution, and thereafter, And a method of mixing with an organic silver salt. The grain size of the photosensitive silver halide is preferably small for the purpose of suppressing white turbidity after image formation, specifically, 0.20 μm or less, more preferably 0.01 μm or more and 0.15 μm or less, and further more preferably 0.02 μm or less.
The thickness is preferably not less than 0.12 μm. The particle size here means
When the silver halide grains are cubic or octahedral so-called normal crystals, the term refers to the length of the edge of the silver halide grains. In the case where the silver halide grains are tabular grains, the diameter refers to a diameter when converted into a circular image having the same area as the projected area of the main surface. In the case of other than normal crystals, for example, in the case of spherical grains, rod-like grains, etc., it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

The shapes of the silver halide grains are cubic,
Octahedral, tabular particles, spherical particles, rod-like particles, potato-like particles and the like can be mentioned. In the present invention, cubic particles and tabular particles are particularly preferable. When tabular silver halide grains are used, the average aspect ratio is preferably 100: 1 to 2: 1, more preferably 50: 1 to 3: 1. Further, grains having rounded corners of silver halide grains can also be preferably used. The surface index (mirror index) of the outer surface of the photosensitive silver halide grains is not particularly limited, but the spectral sensitizing efficiency when a spectral sensitizing dye is adsorbed is high.
The proportion occupied by the [100] plane is preferably high. The ratio is preferably 50% or more, more preferably 65% or more,
80% or more is more preferable. The ratio of the Miller index [100] plane is described in T. Tani; J. Imaging Sci., 29.165 (1985), which utilizes the adsorption dependence of the [111] plane and the [100] plane in the adsorption of the sensitizing dye. It can be obtained by a method. The photosensitive silver halide grains used in the present invention preferably contain a metal or a metal complex of Group VIII of the periodic table. Of the periodic table
Rhodium, ruthenium, osmium and iridium are preferred as the group VIII metal or the central metal of the metal complex. One kind of these metal complexes may be used, or two or more kinds of complexes of the same metal and different metals may be used in combination. The preferred content is in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻³ mol, more preferably 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁴ mol, per mol of silver. As a specific structure of the metal complex, a metal complex having a structure described in JP-A-7-225449 or the like can be used.

As the rhodium compound used in the present invention, a water-soluble rhodium compound can be used. For example, a rhodium (III) halide compound or a rhodium complex salt having a ligand such as halogen, amines, oxalato, etc., for example, hexachlororhodium (II)
I) Complex salts, pentachloroacolodium (III) complex salts, tetrachlorodiachodium (III) complex salts, hexabromorhodium (III) complex salts, hexaamminerhodium (III) complex salts, trioxalathrodium (III) complex salts, and the like. Can be These rhodium compounds are used by dissolving them in water or a suitable solvent. A method generally used for stabilizing a solution of a rhodium compound, that is, an aqueous hydrogen halide solution (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) Etc.) or alkali halides (eg KCl, NaC
l, KBr, NaBr, etc.). Instead of using water-soluble rhodium, it is also possible to add and dissolve another silver halide grain doped with rhodium in the preparation of silver halide.

The addition amount of these rhodium compounds is
1 × 10 per mole of silver halide^-8Mol ~ 5 x 10^-FourMolar range
Enclosure is preferable, and particularly preferably 5 × 10^-8Mol ~ 1 x 1
0^-Five Is a mole. The addition of these compounds
During the production of silver emulsion grains and before each step of coating the emulsion
Can be carried out as needed, but especially during emulsion formation.
And preferably incorporated into silver halide grains.
No.

Ruthenium and Osmiu used in the present invention
Systems are disclosed in JP-A-63-2042, JP-A-1-285941 and
No. 0852, water-soluble complex salts described in 2-20855 and the like
It is added in the form of Particularly preferred are the following formulas
And a six-coordinate complex represented by [ML₆]^n-  Here, M represents Ru or Os, L represents a ligand,
n represents 0, 1, 2, 3 or 4. In this case,
Is not significant and should not be ammonium or alkali gold
Genus ions are used. Preferred ligands include
Rogenide ligand, Cyanide ligand, Cyanide oxide ligand
Ligand, nitrosyl ligand, thionitrosyl ligand, etc.
I can do it. Examples of specific complexes used in the present invention are described below.
Although shown, it is not limited to these.

[RuCl₆]^3- [RuCl_Four(H_TwoO)_Two]^- [RuCl_Five(H_TwoO)]^2-  [RuCl_Five(NO)]^2- [RuBr_Five(NS)]^2-  [Ru (CO)_ThreeCl_Three]^2- [Ru (CO) Cl_Five]^2- [Ru (CO) Br_Five]^2-  [OsCl₆]^3- [OsCl_Five(NO)]^2- [Os (NO) (CN)_Five]^2-  [Os (NS) Br_Five]^2- [Os (O)_Two(CN)_Four]^Four-

The amount of these compounds added was 1
It is preferably in the range of 1 × 10 ⁻⁹ mol to 1 × 10 ⁻⁴ mol per mol, particularly preferably 1 × 10 ⁻⁸ mol to 1 × 10 ⁻⁵ mol. These compounds can be appropriately added at the time of production of silver halide emulsion grains and at each stage before coating the emulsion, but it is particularly preferable to add them at the time of emulsion formation and to incorporate them into silver halide grains. . In order to add these compounds during silver halide grain formation and to incorporate them into silver halide grains, powder of metal complex or
A method in which an aqueous solution dissolved together with NaCl and KCl is added to a water-soluble salt or water-soluble halide solution during particle formation, or as a third solution when a silver salt and a halide solution are simultaneously mixed. And a method in which silver halide grains are prepared by a simultaneous three-liquid mixing method, or a method in which a required amount of an aqueous solution of a metal complex is charged into a reaction vessel during grain formation. In particular, a method of adding a powder or an aqueous solution dissolved together with NaCl and KCl to a water-soluble halide solution is preferable. For the addition to the particle surface, a required amount of an aqueous solution of a metal complex can be charged into the reaction vessel immediately after the formation of the particles, during or at the end of physical ripening, or at the time of chemical ripening.

In the present invention, various iridium compounds can be used, and examples thereof include hexachloroiridium, hexaammineiridium, trioxalatoiridium, hexacyanoiridium, and pentachloronitrosyliridium. These iridium compounds are used after being dissolved in water or an appropriate solvent. However, a method generally used to stabilize the solution of the iridium compound, that is, an aqueous solution of hydrogen halide (for example, hydrochloric acid, hydrobromic acid, hydrofluoric acid) is used. Etc.) or a method of adding an alkali halide (eg, KCl, NaCl, KBr, NaBr, etc.). Instead of using water-soluble iridium, it is also possible to add and dissolve another silver halide grain doped with iridium in advance during the preparation of silver halide. Further, the silver halide grains used in the present invention, cobalt, iron, rhenium, nickel, chromium, palladium, platinum, gold, thallium, copper,
It may contain a metal atom such as lead. As the compound of cobalt, iron and chromium, a hexacyano metal complex can be preferably used. Specific examples include, but are not limited to, ferricyanate, ferrocyanate, hexacyanocobaltate, hexacyanochromate, and hexacyanoruthenate. The phase containing the metal complex in the silver halide may be uniform, may be contained at a high concentration in the core portion, or may be contained at a high concentration in the shell portion, and there is no particular limitation. The above metal is used in an amount of 1 × 10 ⁻⁹ to 1 mol per mol of silver halide.
1 × 10 ^-4 mol is preferred. Further, in order to incorporate the metal, a metal salt in the form of a single salt, a double salt, or a complex salt can be added at the time of preparing particles.

The photosensitive silver halide grains can be desalted by washing with a method known in the art such as a noodle method or a flocculation method, but in the present invention, it may or may not be desalted. . Examples of the gold sensitizer used when performing gold sensitization on the silver halide emulsion used in the present invention include:
The oxidation number of gold may be +1 or +3, and a gold compound usually used as a gold sensitizer can be used. Representative examples include chloroauric acid, potassium chloroaurate, auric trichloride, potassium auric thiocyanate, potassium iodooleate, tetracyano auric acidide, ammonium aurothiocyanate, pyridyl trichlorogold and the like. The addition amount of the gold sensitizer may vary depending on various conditions, per mol of silver halide 10 ^-7 mol to 10 ^-3 mol or less as a guide,
More preferably, it is 10 ^-6 mol or more and 5 × 10 ^-4 or less.

The silver halide emulsion used in the present invention is preferably used in combination with gold sensitization and another chemical sensitization. As other chemical sensitization methods, known methods such as sulfur sensitization, selenium sensitization, tellurium sensitization, and noble metal sensitization can be used. When used in combination with the gold sensitization method,
For example, sulfur sensitization and gold sensitization, selenium sensitization and gold sensitization, sulfur sensitization and selenium sensitization and gold sensitization, sulfur sensitization and tellurium sensitization and gold sensitization Preferred methods include sulfur sensitization, selenium sensitization, tellurium sensitization, and gold sensitization. The sulfur sensitization preferably used in the present invention is usually carried out by adding a sulfur sensitizer and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. Known compounds can be used as the sulfur sensitizer.For example, in addition to the sulfur compound contained in gelatin, various sulfur compounds such as thiosulfate,
Thioureas, thiazoles, rhodanines and the like can be used. Preferred sulfur compounds are thiosulfates and thiourea compounds. The addition amount of the sulfur sensitizer, pH during the chemical ripening, the temperature, but varies depending on various conditions such as the size of the silver halide grains, per mol of silver halide ^10-7
A 10 ^-2 mol, more preferably 10 ^-5 to 10 ^-3 mol.

Known selenium compounds can be used as the selenium sensitizer used in the present invention. That is, it is usually carried out by adding an unstable and / or non-unstable selenium compound and stirring the emulsion at a high temperature of 40 ° C. or higher for a certain time. As unstable selenium compounds, JP-B-44-15748, JP-B-43-13489, JP-A-4-25
Compounds described in JP-A-832, JP-A-4-109240, JP-A-3-21798 and the like can be used. In particular, JP-A-4-324855
It is preferable to use the compounds represented by the general formulas (VIII) and (IX) in the publication. The tellurium sensitizer used in the present invention is a compound which forms silver telluride which is presumed to be a sensitizing nucleus on the surface or inside of silver halide grains. The formation rate of silver telluride in a silver halide emulsion can be tested by the method described in JP-A-5-313284. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides, bis (carbamoyl) tellurides, diacyl tellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, P = Te Compounds having a bond, tellurocarboxylates, Te-organyltellurocarboxylates, di
Use of (poly) tellurides, tellurides, tellurols, telluroacetals, tellurosulfonates, compounds having a P-Te bond, Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, etc. Can be. Specifically, U.S. Patent Nos. 1,623,499, 3,320,069, 3,772,031 and 3,772,031
UK Patent Nos. 235,211; 1,121,496; 1,295,462
No. 1,396,696; Canadian Patent No. 800,958;
No. 204640, No. 3-53693, No. 3-31598, No. 4-
No. 129787, Journal of Chemical Society Chemical Communication (J. Chem. Soc. C
hem.Commun.) 635 (1980), ibid 1102 (1979), ibid 645 (1
979), Journal of Chemical Society
Perkin Transaction (J.Chem.Soc.Perkin.Tran)
s.) 1,2191 (1980), edited by S. Patai, edited by The Chemistry of Organic S.
erenium and Tellunium Compounds), Vol 1 (1986), V
ol 2 (1987). Particularly, compounds represented by formulas (II), (III) and (IV) in JP-A-5-313284 are preferred.

The amount of the selenium and tellurium sensitizers used in the present invention varies depending on the silver halide grains to be used, the conditions of chemical ripening, etc., but generally ranges from 10 ^-8 to 10 ^-2 mol per mol of silver halide. Preferably about 10 ^-7 to 10 ^-3 mol is used. The conditions of the chemical sensitization in the present invention are not particularly limited, but the pH is 5 to 8, the pAg is 6 to 11, preferably 7 to 10, and the temperature is 40 to 95 ° C, preferably 45 to 45 ° C. 85 ° C. In the silver halide emulsion used in the present invention, a cadmium salt, a sulfite, a lead salt, a thallium salt, and the like may coexist in the process of forming silver halide grains or physical ripening. In the present invention, reduction sensitization can be used. As specific compounds of the reduction sensitization method, in addition to ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like can be used. . Reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ions during grain formation. To the silver halide emulsion used in the present invention, a thiosulfonic acid compound may be added by the method described in EP 293,917. The silver halide emulsion in the heat-developable image recording material of the present invention may be only one kind or two or more kinds (for example, those having different average grain sizes, those having different halogen compositions,
Those having different crystal habits and those having different chemical sensitization conditions) may be used in combination.

The amount of the photosensitive silver halide to be used is 0.01 mol or more to 0.5 mol of the photosensitive silver halide per 1 mol of the organic silver salt.
Mol or less, preferably 0.02 mol or more and 0.3 mol or less, particularly preferably 0.03 mol or more and 0.25 mol or less.
Regarding the mixing method and the mixing conditions of the separately prepared photosensitive silver halide and organic silver salt, the prepared silver halide particles and organic silver salt were mixed with a high-speed stirrer, ball mill, sand mill, colloid mill, vibration mill, homogenizer, etc. And the like, or a method of preparing an organic silver salt by mixing photosensitive silver halide prepared at any timing during the preparation of the organic silver salt. There is no particular limitation as long as it appears in. In the present invention, a sensitizing dye can be used. Any sensitizing dye may be used as long as it can spectrally sensitize the silver halide grains in a desired wavelength region when adsorbed on the silver halide grains. As sensitizing dyes, cyanine dyes, merocyanine dyes, complex cyanine dyes,
Complex merocyanine dyes, holo-holer cyanine dyes, styryl dyes, hemicyanine dyes, oxonol dyes, hemioxonol dyes and the like can be used. Useful sensitizing dyes for use in the present invention are, for example, RESEAR
CH DISCLOSURE Item17643 IV-A (December 1978, p.23), I
tem 1831X (August 1979, p. 437). In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of the light source of various laser imagers, scanners, imagesetters and plate making cameras can be advantageously selected.

Examples of spectral sensitization to red light include He-Ne
For a so-called red light source such as a laser, a red semiconductor laser or an LED, the I-1 described in JP-A-54-18726 is used.
To I-38, I-1 described in JP-A-6-75322.
To I-35 and the compounds of I-1 to I-34 described in JP-A-7-287338, the dyes 1 to 20 described in JP-B-55-39818, and JP-A-62-284343. I-1 described in
To I-37 and the compounds of I-1 to I-34 described in JP-A-7-287338 are advantageously selected. 750
For semiconductor laser light sources in the wavelength range of ~ 1400 nm,
A variety of known dyes, including cyanine, merocyanine, styryl, hemicyanine, oxonol, hemioxonol, and xanthene dyes, can be spectrally sensitized favorably. Useful cyanine dyes are, for example, cyanine dyes having basic nuclei such as thiazoline nuclei, oxazoline nuclei, pyrroline nuclei, pyridine nuclei, oxazole nuclei, thiazole nuclei, selenazole nuclei and imidazole nuclei. Preferred useful merocyanine dyes include, in addition to the above basic nuclei, acidic nuclei such as thiohydantoin nucleus, rhodanine nucleus, oxazolidinedione nucleus, thiazolinedione nucleus, barbituric acid nucleus, thiazolinone nucleus, malononitrile nucleus and pyrazolone nucleus. Including. Among the above-mentioned cyanine and merocyanine dyes, those having an imino group or a carboxyl group are particularly effective.
For example, U.S. Pat.Nos. 3,761,279, 3,719,495, 3,877,943, British Patent 1,466,201,
No. 1,469,117, No. 1,422,057, Japanese Patent Publication No. 3-10391,
JP-A-6-52387, JP-A-5-341432, JP-A-6-94781
And known dyes as described in JP-A-6-301141 and JP-A-6-301141.

Particularly preferred as the structure of the dye used in the present invention is a cyanine dye having a thioether bond-containing substituent (for example, JP-A Nos. 62-58239 and 3-1).
No. 38638, 3-138642, 4-255840,
No. 5-72659, No. 5-72661, No. 6-222491, No. 2-230506, No. 6-258757, No. 6-317868
JP-A-6-324425, JP-T-Hei 7-500926, the dye described in U.S. Pat.No. 5,541,054), a dye having a carboxylic acid group (for example, JP-A-3-163440, No. 6-301141, the dyes described in U.S. Pat.No. 5,441,899), merocyanine dyes, polynuclear merocyanine dyes and polynuclear cyanine dyes (JP-A-47-6329,
No. 49-105524, No. 51-127719, No. 52-80829, No. 54-61517, No. 59-214846, No. 60-6750
No. 63-159841, JP-A-6-35109,
No. 6-59381, No. 7-146537, No. 7-146537, Japanese Patent Publication No. 55-50111, British Patent No. 1,467,638,
Dyes described in U.S. Pat. No. 5,281,515). Further, as a dye for forming a J-band, U.S. Pat.
5, the dye described in JP-A-2-96131, JP-A-59-48753
There are dyes disclosed in Japanese Patent Application Laid-Open Publication No. H11-157, and these dyes can be preferably used in the present invention.

These sensitizing dyes may be used alone.
Two or more kinds may be used in combination. In particular, combinations of sensitizing dyes are frequently used for supersensitization. Along with the sensitizing dye, the emulsion may contain a dye which does not itself have a spectral sensitizing effect or a substance which does not substantially absorb visible light and exhibits supersensitization. Useful sensitizing dyes, combinations of dyes exhibiting supersensitization and substances exhibiting supersensitization are Re.
search Disclosure Volume 176, 17643 (Issued December 1978) p. 23
IV, section J, or JP-B-49-25500, JP-B-43-4933, JP-A-59-19032, and JP-A-59-192242. To add sensitizing dyes to a silver halide emulsion, they may be directly dispersed in the emulsion,
Or water, methanol, ethanol, propanol,
Acetone, methylcellosolve, 2,2,3,3-tetrafluoropropanol, 2,2,2-trifluoroethanol, 3-methoxy-1-propanol, 3-methoxy-1-butanol, 1-methoxy-2- A solvent such as propanol and N, N-dimethylformamide alone or in a mixed solvent may be added to the emulsion.

Further, as disclosed in US Pat. No. 3,469,987, a dye is dissolved in a volatile organic solvent, and this solution is dispersed in water or a hydrophilic colloid. As disclosed in JP-B-44-23389, JP-B-44-27555, and JP-B-57-22091, a dye is dissolved in an acid, and this solution is added to an emulsion. Or, a method of adding an acid or a base to the emulsion as an aqueous solution in the coexistence, U.S. Pat.No. 3,822,135,
No. 4,006,025, a method of adding an aqueous solution or a colloidal dispersion in the presence of a surfactant to an emulsion as disclosed in the specification of JP-A-53-102733 and JP-A-58-105141. JP-A-51-74624 discloses a method in which a dye is directly dispersed in a hydrophilic colloid as disclosed in JP-A-51-294, and a method of adding the dispersion to an emulsion, as disclosed in JP-A-51-74624. A method of dissolving the dye using the method described above and adding this solution to the emulsion can also be used. Also, ultrasonic waves can be used for dissolution.

The sensitizing dye may be added to the silver halide emulsion at any time during the preparation of the emulsion which has been found to be useful. For example, U.S. Pat.Nos. 2,735,766, 3,628,960, 4,18
3,756, 4,225,666, JP-A-58-184
As disclosed in the specifications of JP-A-142, JP-A-60-196749 and the like, the timing of silver halide grain formation and / or the timing before desalination, during and / or after desalination, Emulsion coating before the start of ripening, as disclosed in the specification of JP-A-58-113920, etc., immediately before or during chemical ripening, after chemical ripening, and before coating. Any time before the addition, it may be added in the process. Further, as disclosed in U.S. Pat.No.4,225,666, specifications such as JP-A-58-7629, the same compound may be used alone or in combination with a compound having a different structure. It may be divided and added during the chemical ripening step or after the completion of the chemical ripening, or divided before or during the chemical ripening and after the completion. You may change and add it.

The amount of the sensitizing dye used in the present invention may be a desired amount according to the performance such as sensitivity and fog.
The amount is preferably from 10 ^-6 to 1 mol, more preferably from 10 ^-4 to 10 ^-1 mol, per mol of silver halide in the photosensitive layer. The surface pH of the heat-developable image recording material of the present invention before the heat development treatment is preferably 6 or less from the viewpoint of reducing fogging during storage, particularly 5.5 or less, more preferably 5.3 or less. . The lower limit is not particularly limited, but is about 3. Membrane 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 from the viewpoint of reducing the film surface pH. In particular, ammonia is preferable in achieving a low film surface pH since ammonia is easily volatilized and can be removed before the application step and the heat development.

When measuring the film surface pH of the heat-developable image-recording material of the present invention, the heat-developable image-recording material 2.5 cm × 2.5 cm before heat-development is folded into a boat shape, It is preferable that 300 μl of distilled water is dropped on the side and left for 30 minutes, and then the dropped liquid is measured for 1 minute with pHBOY-P2 (manufactured by Shindengen Kogyo Co., Ltd., semiconductor type pH meter). In the photosensitive layer of the heat-developable image recording material of the present invention, a polyhydric alcohol (for example, glycerin and diol of the type described in U.S. Pat.No. 2,960,404) as a plasticizer and a lubricant, U.S. Pat. And the fatty acids or esters described in No. 3,121,060,
For example, a silicone resin described in British Patent No. 955,061 can be used. The image-forming layer or the protective layer of the image-forming layer in the present invention is described in U.S. Pat. Photographic elements containing various light absorbing materials and filter dyes. Also, for example, U.S. Pat.
The dye can be mordant as described in US Pat. The amount of the filter dye used is preferably such that the absorbance at the exposure wavelength is 0.1 to 3, and particularly preferably 0.2 to 1.5.

In the photosensitive layer of the heat-developable image recording material of the present invention, various dyes and pigments can be used from the viewpoint of improving color tone and preventing irradiation. Dyes and pigments used in the photosensitive layer of the heat-developable image recording material of the present invention may be any, for example, pigments and dyes described in the color index, specifically pyrazoloazole dye, anthraquinone dye, azo dye, Organic pigments such as azomethine dyes, oxonol dyes, carbocyanine dyes, styryl dyes, triphenylmethane dyes, indoaniline dyes, indophenol dyes, and phthalocyanines, and inorganic pigments. Preferred dyes used in the present invention include anthraquinone dyes (e.g., compounds 1 to 9 described in JP-A-5-341441, compounds 3-6 to 18 and 3-23 to 38 described in JP-A-5-165147). Azomethine dye)
(E.g., compounds 17 to 47 described in JP-A-5-341441), indoaniline dyes (e.g., compounds 11 to 19 described in JP-A-5-289227, compounds described in JP-A-5-341441)
47, compounds 2-10 to 11 described in JP-A-5-165147, and azo dyes (compounds 10 to 16 described in JP-A-5-341441). As a method for adding these dyes, any method such as a solution, an emulsion, a solid fine particle dispersion, and a state in which the dye is mordanted with a polymer mordant may be used. The amount of these compounds to be used is determined depending on the target absorption, but it is generally preferable to use them in a range of 1 × 10 ⁻⁶ g to 1 g per m ² .

The heat-developable image recording material of the present invention comprises a support having at least one photosensitive layer containing a silver halide emulsion on one side and a back layer on the other side. Even having a photosensitive layer containing at least one silver halide emulsion on both sides of the support,
A so-called double-sided photosensitive material may be used. In the present invention, the back layer preferably has a maximum absorption in a desired range of about 0.3 or more and 2.0 or less. If the desired range is 750 to 1400 nm, the optical density at 750 to 360 nm is 0.005
It is preferably at least 0.5 and more preferably less than 0.5
It is preferable that the antihalation layer has an optical density of 0.001 or more and less than 0.3. When the desired range is 750 nm or less, the halation is such that the maximum absorption in the desired range before image formation is 0.3 or more and 2.0 or less, and the optical density at 360-750 nm after image formation is 0.005 or more and less than 0.3. Preferably, it is a prevention layer. The method for lowering the optical density after image formation to the above range is not particularly limited. For example, as described in Belgian Patent No. 733,706, a method in which the density of a dye is reduced by decolorization by heating,
And a method of reducing the density by decoloring by light irradiation described in JP-A-17833.

When an antihalation dye is used in the present invention, the dye has a desired absorption in a desired range, has a sufficiently low absorption in the visible region after treatment, and has a desirable absorbance spectrum shape of the back layer. Any compound can be used, if possible. For example, the following are disclosed, but the present invention is not limited thereto. As a single dye, JP-A-59-56458, JP-A-2-216140, JP-A-7-13295, JP-A-7-11432, U.S. Pat.
380,635 described dyes, JP-A-2-68539 JP No.
Page 13, lower left column, line 1 to page 14, lower left column, line 9, 3-24539
JP-A No. 14139/136, JP-A-53-132334, JP-A-56-501480 include compounds described in the right lower column of page 16 from the lower left column of page 14, and as dyes which are decolorized by the treatment. Gazette, ibid. 57-1
No. 6060, No. 57-68831, No. 57-101835,
JP 59-182436 JP, JP-A 7-36145 JP, 7-199409
JP, JP-B-48-33692, JP-B-50-16648, JP-B-2-41734, U.S. Pat.No.4,088,497,
4,283,487, 4,548,896, 5,187,04
There is No. 9 specification.

The photosensitive layer of the heat-developable image recording material of the present invention,
A hardener may be used for each layer such as the protective layer and the back layer.
Examples of hardeners include U.S. Pat.No. 4,281,060,
Polyisocyanates described in JP-A-6-208193, epoxy compounds described in U.S. Pat.No. 4,791,042, etc., and vinyl sulfones described in JP-A-62-89048 and the like System compounds and the like are used. In the present invention, a surfactant may be used for the purpose of improving coating properties and charging. As the surfactant, any surfactant such as nonionic, anionic, cationic, and fluorine can be used as appropriate. Specifically,
No. 62-170950, Fluoropolymer surfactants described in U.S. Pat.No. 5,380,644, etc., Fluorosurfactants described in JP-A-60-244945, JP-A-63-188135, etc. And polysiloxane surfactants described in U.S. Pat. No. 3,885,965 and polyalkylene oxides and anionic surfactants described in JP-A-6-301140.

The heat-developable image recording material of the present invention can be used, for example, as described in US Pat. No. 2,861,056 and US Pat. Ionic polymers as described or insoluble inorganic salts as described in U.S. Pat.No. 3,428,451, including tin oxide fine particles described in JP-A-60-252349 and JP-A-57-104931, and the like. It may have a layer. As a method for obtaining a color image using the heat-developable image recording material of the present invention, there is a method described in JP-A-7-13295, page 10, left column, line 43 to 11 left column, line 40. Also,
British Patent No. 1,326,889 as stabilizer for color dye images
And U.S. Pat. Nos. 3,432,300, 3,698,909, 3,574,627, 3,573,050, 3,764,337 and 4,042,394. Additional layers in the heat-developable image recording material of this invention, such as a dye-receiving layer for receiving a migrating dye image, an opacifying layer if reflective printing is desired, a protective topcoat layer and those known in the photothermographic art. It may include a primer layer and the like. The image recording material of the present invention is preferably capable of forming an image with only one image recording material, and it is preferable that a functional layer necessary for image formation such as an image receiving layer does not become another image recording material.

In the present invention, the exposure apparatus used for imagewise exposure may be any apparatus capable of performing exposure with an exposure time of less than 10 ^-7 seconds.
D), 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 of an electromagnetic wave spectrum in a target wavelength range. For example, for LD,
Dye lasers, gas lasers, solid-state lasers, semiconductor lasers, and the like can be used. The exposure is performed by overlapping the light beams of the light source, and the overlap means that the sub-scanning pitch width is smaller than the beam diameter. For example, the overlap can be quantitatively expressed by FWHM / sub-scanning pitch width (overlap coefficient) when the beam diameter is represented by a half width of beam intensity (FWHM). In the present invention, the overlap coefficient is preferably 0.2 or more. The scanning method of the light source of the exposure apparatus used in the present invention is not particularly limited, and a cylinder outer surface scanning method, a cylinder inner surface scanning method, a plane scanning method, or the like can be used. The channel of the light source may be a single channel or a multi-channel, but in the case of a cylindrical outer surface type, a multi-channel is preferably used.

The heat-developable image recording material of the present invention has a low haze upon exposure and tends to cause interference fringes. This interference fringe generation prevention technology is disclosed in Japanese Patent Application Laid-Open No. 5-113548 and the like, in which a laser beam is obliquely incident on a photosensitive material, and in WO95 / 31754. A known method using a multimode laser is known, and it is preferable to use these techniques. In the heat development step of the image forming method for a heat-developable image recording material of the present invention, the image may be developed by any method. Usually, the image recording material exposed imagewise is heated and developed. As a preferred embodiment of the heat developing machine used, Japanese Patent Publication No. 5-56499, Patent Publication No. 684453, Japanese Patent Application Laid-Open No. 9-292695 as a type in which a heat development image recording is brought into contact with a heat source such as a heat roller or a heat drum. , JP 9-29
No. 7385 and the thermal developing machine described in WO95 / 30934, as a non-contact type, JP-A-7-13294, WO97 / 28489, WO97 / 28488 and There is a heat developing machine described in JP-A-97 / 28487. A particularly preferred embodiment is a non-contact type thermal developing machine. The preferred development temperature is 80 to 250 ° C, more preferably 100 to 140 ° C. The development time is preferably from 1 to 180 seconds, more preferably from 10 to 90 seconds. As a method for preventing processing unevenness due to dimensional change during heat development of the heat-developable image recording material of the present invention, after heating for 5 seconds or more so that an image does not appear at a temperature of 80 ° C or more and less than 115 ° C, 110 ° C or more 140 ℃
In the following, a method of forming an image by heat development (so-called multi-stage heating method) is effective.

FIG. 4 shows an example of the configuration of a heat developing machine used in the heat development of the heat-developable image recording material of the present invention. FIG. 4 shows a side view of the heat developing machine. The heat developing machine shown in FIG. 4 carries in a pair of carry-in rollers 51 (a lower roller is a heat roller) for carrying the heat-developable image recording material 50 into a heating unit while correcting and preheating the heat-developable image recording material 50 in a plane, and heat development after heat development after heat development. It has a carry-out roller pair 52 for carrying out the image recording material 50 from the heating unit while correcting it into a planar shape. The thermally developed image recording material 50 is thermally developed while being transported from the carry-in roller pair 51 to the carry-out roller pair 52. The conveying means for conveying the heat-developed image recording material 50 during the heat development is provided with a plurality of rollers 53 on the side where the surface having the image forming layer is in contact,
A smooth surface 54 on which a non-woven fabric (for example, made of polyphenylene sulfide or Teflon) or the like is attached is provided on the opposite side to which the back surface contacts. The back surface of the heat-developable image recording material 50 is conveyed by sliding a plurality of rollers 53 in contact with the surface having the image forming layer, on the smooth surface 54. The heating means is provided with a heater 55 at the upper portion of the roller 53 and at the lower portion of the smooth surface 54 so as to be heated from both sides of the thermally developed image recording material 50. As a heating means in this case, a plate heater or the like can be used. The clearance between the roller 53 and the smooth surface 54 varies depending on the member of the smooth surface, but is appropriately adjusted to a clearance that allows the heat-developable image recording material 50 to be transported. Preferably 0
１1 mm.

The material of the surface of the roller 53 and the smooth surface 54
The member having high temperature durability has a high temperature
Any material may be used as long as it does not hinder the conveyance of the roller. However, the material of the roller surface is preferably silicon rubber, and the member having a smooth surface is preferably a nonwoven fabric made of aromatic polyamide or Teflon (PTFE). It is preferable to use a plurality of heaters as the heating means and to set the heating temperature freely. The pre-heating section upstream of the heat development processing section has a temperature and time lower than the heat development temperature (for example, about 10 to 30 ° C.) and sufficient for evaporating the water content in the heat development image recording material. The temperature is preferably set to a temperature higher than the glass transition temperature (Tg) of the support of the heat-developable image recording material 50 so that development unevenness does not occur.

The guide plate 5 is located downstream of the heat development processing section.
6 is installed, and further, a slow cooling unit is installed. The guide plate is preferably made of a material having a low thermal conductivity, and is preferably cooled gradually to prevent deformation of the heat-developable image recording material. Although the above has been described with reference to the illustrated example, the invention is not limited to this example. For example, the thermal developing machine used in the embodiment of the present invention, such as that described in JP-A-7-13294, may have various configurations. In the case of the multi-stage heating method preferably used in the present invention, in the above-described apparatus, two or more heat sources having different heating temperatures may be provided, and heating may be performed continuously at different temperatures. 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 and the like, a plurality of these layers are simultaneously superposed in an aqueous system. Apply. The coating method includes extrusion coating, slide bead coating, curtain coating, etc.
The slide bead coating method disclosed in FIG. 1 of the specification of Japanese Patent Application No. 10-292849 is particularly preferred.

In the case of a silver halide photographic material using gelatin as a main binder, the material is rapidly cooled in a first drying zone provided downstream of a coating table, and as a result, gelatinization of gelatin occurs and the coating film is cooled. Is solidified. The coating film that has been cooled and solidified and has stopped flowing is guided to the subsequent second drying zone, where the solvent in the coating solution is volatilized and formed into a film in the subsequent drying zone. As a drying method after the second drying zone, an air loop method in which a jet is blown from a U-shaped duct to a roller-supported support, or a support in which the support is wound around a cylindrical duct in a helical shape, and conveyed and dried. A fire method (air floating method) and the like can be mentioned. In the case of a coating liquid in which the main component of the binder is a polymer latex, the flow of the coating liquid cannot be stopped by rapid cooling, so that the preliminary drying may be insufficient only in the first drying zone. In this case, in a drying method such as a silver halide photographic light-sensitive material, uneven flow and uneven drying occur, and a serious defect is likely to occur on a coated surface.

The preferred drying method in the present invention is at least until the constant rate drying is completed, regardless of the first drying zone or the second drying zone as described in Japanese Patent Application No. 10-282949. Is a method of drying in a horizontal drying zone. The transport of the support immediately after the application until it is led to the horizontal drying zone may or may not be a horizontal transport, and the rising angle with respect to the horizontal direction of the coating machine may be between 0 and 70 °. . In addition, the horizontal drying zone only needs to be conveyed within ± 15 ° up and down with respect to the horizontal direction of the coating machine, and does not mean horizontal conveyance. The constant-rate drying in the present specification means a drying process in which a liquid film temperature is constant and all the heat flowing in is used for evaporating the solvent. At the end of drying, the rate of drying decreases at the end of drying due to various factors (such as the rate of diffusion of moisture inside the material and the evaporation surface receding), and the applied heat is also used to raise the liquid film temperature. Drying process. The critical moisture content at which the transition from the constant rate process to the rate reduction process is 200 to 300%. When constant-rate drying ends,
Since drying proceeds sufficiently until the flow stops, a drying method such as a silver halide photographic light-sensitive material can also be employed.However, in the present invention, drying is performed in a horizontal drying zone until the final drying point even after constant-rate drying. Preferably.

The preferable drying conditions in the present invention are as follows: the drying conditions for forming the image forming layer and / or the protective layer are such that the liquid film surface temperature during constant-rate drying is the minimum film forming temperature (MTF; Higher than the Tg of the polymer, usually 3-5 ° C.)
In many cases, the temperature is between 40C and 40C. Further, the dry-bulb temperature during the rate-decreasing drying is preferably a temperature lower than the Tg of the support to be used (usually 80 ° C. or lower in the case of PET). The liquid film surface temperature in this specification refers to the solvent liquid film surface temperature of the coating liquid film applied to the support, and the dry bulb temperature refers to the temperature of the drying air in the drying zone. When drying is performed under the condition that the liquid film surface temperature during constant-rate drying is low, the drying tends to be insufficient. For this reason, particularly, the film forming property of the protective layer is significantly reduced, and cracks are easily generated on the film surface. In addition, the film strength is weakened, and serious problems such as susceptibility to damage during transport in an exposure machine or a heat developing machine are likely to occur.

On the other hand, when dried under the condition of a high liquid film surface temperature, the protective layer mainly composed of the polymer latex quickly forms a film, while the lower layer such as the image forming layer does not stop flowing. Therefore, surface irregularities are likely to occur. Further, when excessive heat higher than the glass transition temperature is applied to the support (base), the dimensional stability and the curl resistance of the photosensitive material tend to deteriorate. The same applies to the sequential coating in which the lower layer is applied and then dried and then the upper layer is applied. The pH difference between the coating solution for the image forming layer and the coating solution for the protective layer is preferably 2.5 or less, and the smaller the pH difference, the better. When the pH difference of the coating liquid is large, micro-aggregation is likely to occur at the coating liquid interface, and a serious surface failure such as a coating streak tends to occur during continuous continuous coating. The coating solution viscosity of the image forming layer is preferably from 15 to 100 cp at 25 ° C., more preferably from 30 to 70 cp. On the other hand, the coating liquid viscosity of the protective layer is preferably 5 to 75 cp at 25 ° C,
More preferably, it is 20 to 50 cp. These viscosities are measured by a B-type viscometer.

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%, and the winding shape can be selected from outside or inside the Em surface according to the subsequent processing form. In addition, it is preferable that the wrapping humidity of the photosensitive material is controlled in the range of 20 to 55% (measured at 25 ° C.). In the present invention, the defoaming of the coating liquid is performed by degassing under reduced pressure before applying the coating liquid, further maintaining the pressurized state of 1.5 kg / cm ² or more, and continuously without generating a gas-liquid interface. A method of applying ultrasonic vibration while feeding a liquid is preferable. Specifically,
The method described in JP 6405 (page 4, line 20 to page 7, line 11) is preferred. For example, as an apparatus for performing such defoaming, there is an apparatus shown in FIG. 3 of the embodiment of Japanese Patent Application No. 10-290003. Conventionally, a photographic emulsion coating solution, which is a viscous liquid containing silver halide and containing gelatin as a substrate, usually dissolves and disappears in the liquid simply by sending it under pressure, so that the coating is performed under atmospheric pressure during coating. Almost no bubbles are deposited even if the pressure is returned to the above range. However, in the case of a coating solution containing an organic silver salt used in the present embodiment and having thixotropic properties, defoaming is not sufficient only by pressurized liquid sending, and the liquid is transferred while preventing liquid-gas interface from being generated. It is necessary to defoam by applying sonic vibration.

The pressure condition is 1.5 kg / cm ² or more, 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 applied ultrasonic wave is 0.2 V or more, preferably 0.5 V or more and 3.0 V or less. Generally, it is preferable that the sound pressure is high. It becomes high temperature and causes fog. The frequency is not particularly limited, but is usually 10 kHz or more, preferably 20 kHz to 20 kHz.
0 kHz. In addition, decompression degassing is performed in the tank (usually,
(Sealing tank or storage tank) is closed and decompressed to increase the diameter of bubbles in the coating solution and to increase the buoyancy to deaerate. Preferably -250 mmHg
The lower pressure condition is not particularly limited but is usually about -800 mmHg. The decompression time is 30 minutes or more, preferably 45 minutes or more, and the upper limit is not particularly limited. Hereinafter, the effects of the present invention will be described with reference to examples, but the present invention is not limited thereto.

[0127]

EXAMPLES Example 1 << Preparation of Dispersion A of Organic Acid Silver >> 876 g of behenic acid (product name: Edenor C22-85R) manufactured by Henkel, 4230 distilled water
Then, 492 ml of 5N-NaOH aqueous solution and 1200 ml of tert-butyl alcohol were mixed and reacted at 75 ° C. with stirring for 1 hour to obtain a sodium behenate solution. Separately, 2062 ml of an aqueous solution (pH 4.0) containing 404 g of silver nitrate was prepared and kept at 10 ° C. 6350ml of distilled water and 3
The reaction vessel containing 00 ml of tert-butyl alcohol was kept at 30 ° C., and the whole amount of the sodium behenate solution and the whole amount of the silver nitrate aqueous solution were added at a constant flow rate over 62 minutes, 10 seconds and 60 minutes while stirring. . 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 only 9 minutes and 30 seconds after the completion of the silver nitrate aqueous solution, only the sodium behenate solution was added. It was made to be added.

At this time, the temperature in the reaction vessel was set at 30 ° C., and the temperature was controlled so as not to rise. Further, the piping of the addition system of the sodium behenate solution was kept warm by steam tracing, and the amount of steam was controlled so that the liquid temperature at the outlet at the tip of the addition nozzle became 75 ° C. The piping of the silver nitrate aqueous solution addition system was kept warm by circulating cold water outside the double pipe. The addition position of the sodium behenate solution and the addition position of the aqueous silver nitrate solution were arranged symmetrically with respect to the stirring axis, and were adjusted to a height such that they did not come into contact with the reaction solution. After completion of the addition of the sodium behenate solution, the mixture is left to stir at the same temperature for 20 minutes,
The temperature was lowered to 25 ° C. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of the filtrate became 30 μS / cm. The solid thus obtained was stored as a wet cake without drying. The morphology of the obtained silver behenate grains was evaluated by electron microscopy. As a result, it was found to be flaky crystals having an average projected area diameter of 0.52 μm, an average grain thickness of 0.14 μm, and a variation coefficient of the average equivalent sphere diameter of 15%.

Next, a dispersion of silver behenate was prepared by the following method. To a wet cake having a dry solid content of 100 g, 7.4 g of polyvinyl alcohol (trade name: PVA-217, average degree of polymerization: about 1700) and water were added, and the total amount was 3850 g, and the mixture was preliminarily dispersed by a homomixer. .
Next, the predispersed undiluted solution is dispersed in a dispersing machine (trade name: Microfluidizer M-110S-EH, manufactured by Microfluidics International Corporation, G1
0Z interaction chamber)
The mixture was adjusted to 0 kg / cm ² and treated three times to obtain a silver behenate dispersion. In the cooling operation, a coiled heat exchanger was mounted before and after the interaction chamber, and the temperature of the refrigerant was adjusted to a desired dispersion temperature. The silver behenate particles contained in the silver behenate dispersion thus obtained have a volume-weighted average diameter.
0.52μm, coefficient of variation 15% particles, viscosity is 18mPa · s
Met. Particle size # measurements are available from Malvern Instruments
Ltd. MasterSizerX. When evaluated by electron microscopy, the ratio of the long side to the short side was 1.5, and the particle thickness was 0.1.
The average aspect ratio (ratio of the circle equivalent diameter of the projected area of the grain to the grain thickness) was 5.1 μm.

<< Preparation of Dispersion B of Organic Acid Silver >> Dispersion B was prepared using a small crystallization apparatus as shown in FIG. In the tank 32, behenic acid manufactured by Henkel (product name: Edenor)
C22-85R) 876 g, distilled water 4,230 ml, t
While stirring 1,200 ml of ert-butanol at 75 ° C., 492 ml of a 5N-NaOH aqueous solution was added over 5 minutes, and the mixture was reacted for 60 minutes to obtain a sodium behenate solution. Further, 2,062 ml of an aqueous solution (pH 4.0) of 404 g of silver nitrate was prepared in the tank 31 and kept at 10 ° C. The aqueous silver nitrate solution was added at a constant flow rate of 29 cc / min while stirring a pipeline mixer LR-I manufactured by Mizuho Industry Co., Ltd. at 38 in FIG. 3 at 38 rpm. 98 sodium acid solution
It was added at a constant flow rate of cc / min and stocked in the tank 40 via the heat exchanger 39. However, when the supply of the cooling water to the heat exchanger was stopped and the cooling water of 10 ° C. was supplied to the jacket of the tank 40 at 20 L / min, the average temperature in the tank was 35 ° C. The mixture was allowed to stand with stirring for 20 minutes, and the temperature was lowered to 25 ° C. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of permeated water became 30 μS / cm. The solid thus obtained was stored as a wet cake without drying. After that, the dispersion was performed in the same manner as the dispersion of the organic acid silver A to obtain the dispersion of the organic acid silver B.

<< Preparation of Dispersion C of Organic Acid Silver >> Dispersion C was prepared using a small crystallization apparatus as shown in FIG. In the tank 32, behenic acid manufactured by Henkel (product name: Edenor)
C22-85R) 876 g, distilled water 4,230 ml, t
While stirring 1,200 ml of ert-butanol at 75 ° C., 492 ml of a 5N-NaOH aqueous solution was added over 5 minutes, and the mixture was reacted for 60 minutes to obtain a sodium behenate solution. Further, 2,062 ml of an aqueous solution (pH 4.0) of 404 g of silver nitrate in the tank 31 and 6,000 ml of pure water in the tank 41 were kept at 10 ° C. 3 in FIG.
8 Pipeline mixer LR manufactured by Mizuho Industry Co., Ltd.
While stirring Form I at 10,000 rpm, the above-mentioned aqueous solution of silver nitrate was added at a constant flow rate of 29 cc / min and pure water at a constant flow rate of 98 cc / min, and after 5 seconds had elapsed, the sodium behenate solution was then added at a constant rate of 98 cc / min. It was added at a flow rate and stored in a tank 40 via a heat exchanger 39. However, the supply of cooling water to the heat exchanger is stopped, and 1
When cooling water at 0 ° C. was supplied at 20 L / min, the average temperature in the tank was 30 ° C. The mixture was allowed to stand with stirring for 20 minutes, and the temperature was lowered to 25 ° C. Thereafter, the solid content was separated by suction filtration, and the conductivity of the solid content was 30 μS /
cm. The solid content thus obtained is
It was stored as a wet cake without drying. After that, the dispersion was performed in the same manner as the dispersion of the organic acid silver A to obtain the dispersion of the organic acid silver C.

<< Preparation of Organic Acid Silver Dispersion D >> Dispersion C
Prepared in the same manner as However, 4 vol%
Of tert-butanol aqueous solution was prepared and added at a constant flow rate of 98 cc / min.

<< Preparation of Dispersion E of Organic Acid Silver >> Dispersion E was prepared using a small crystallization apparatus as shown in FIG. In the tank 12, behenic acid manufactured by Henkel (product name: Edenor)
C22-85R) 876 g, distilled water 4,230 ml, t
While stirring 1,200 ml of ert-butanol at 75 ° C., 492 ml of a 5N-NaOH aqueous solution was added over 5 minutes, and the mixture was reacted for 60 minutes to obtain a sodium behenate solution. Further, 2,062 ml of an aqueous solution (pH 4.0) of 404 g of silver nitrate was prepared in the tank 11 and kept at 10 ° C. Further, 6,000 ml of pure water was measured into the tank 20 and circulated through the pump 17 at a flow rate of 1,000 cc / min. The aqueous silver nitrate solution was added at a constant flow rate of 29 cc / min while stirring a pipeline mixer LR-I manufactured by Mizuho Industry Co., Ltd. as shown at 18 in FIG. 2 at 10,000 rpm. The sodium acid solution was added at a constant flow rate of 98 cc / min, and was stored in the tank 20 via the heat exchanger 19. Here, cooling water of 10 ° C. is applied to the heat exchanger and the jacket of the tank 20.
When supplied at L / min, the average temperature in the tank is 30 ° C
Met. Leave to stir for 20 minutes, 25
The temperature was lowered to ° C. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water until the conductivity of permeated water became 30 μS / cm. The solid thus obtained was stored as a wet cake without drying. Thereafter, the dispersion was performed in the same manner as the dispersion of the organic acid silver A to obtain the dispersion of the organic acid silver E.

<< Preparation of Organic Acid Silver Dispersion F >> Dispersion B
Prepared in the same manner as However, when cooling water of 5 ° C. was passed through the heat exchanger 39, the average temperature in the tank 40 was 30 ° C.
Met.

<< Preparation of Dispersion G of Organic Acid Silver >> Dispersion E
Prepared in the same manner as However, when cooling water of 5 ° C. was passed through the heat exchanger 19, the average temperature in the tank 20 was 25 ° C.
Met. Preparation conditions of dispersions A to G thus obtained,
Table 1 shows physical properties such as average particle diameter and viscosity.

[0136]

[Table 1]

<< Preparation of Silver Halide Emulsion >> (Emulsion A) Alkaline-treated gelatin (calcium
11g and potassium bromide 30
mg, sodium benzenethiosulfonate 10mg
After adjusting the pH to 5.0 at a temperature of 40 ° C, contains 18.6 g of silver nitrate
159 ml of an aqueous solution and 1 mol / l of potassium bromide (NH_Four)
_TwoRhCl_Five(H_TwoO) 5 × 10^-6Mol / l and K_Three
IrCl₆2 × 10^-FivePAg aqueous solution containing mol / l
6 minutes 30 minutes by control double jet method while keeping at 7.7
The addition was made over a second period. Then, an aqueous solution containing 55.5 g of silver nitrate
476 ml of liquid, 1 mol / l of potassium bromide and K_ThreeIrC
l₆2 × 10^-Five Halogen salt aqueous solution containing mol / liter
Control Double jet method while keeping pAg 7.7 28
Minutes over 30 seconds. After that, the pH was lowered and the sedimentation
And subjected to desalting treatment. Compound A (0.17 g, average molecular weight 10,000)
5000 low molecular weight gelatin (calcium content 20pp
m or less) 51.1 g was added to adjust to pH 5.9 and pAg 8.0. Obtained
The average grain size is 0.08 μm and the projected area variation coefficient is 9
%, (100) cubic particles having a 90% ratio. Thus obtained
Temperature of the silver halide grains to 60 ° C.
Add 76 μmol of sodium nzenthiothiosulfonate and add 3
After minutes, add 71 μmol of triethylthiourea, and add 100 minutes.
Matured, 4-hydroxy-6-methyl-1,3,3a,
5 × 10 7-tetrazaindene^-FourAfter adding mol
The temperature was lowered. After that, keep the temperature at 40 ° C,
4.7 × 10 per mole^-2Molar KBr, 12.8 × 10^-FourMole
The following sensitizing dye A, 6.4 × 10^-3Stir moles of compound B
20 minutes later, quench to 30 ° C and add silver halide milk
Preparation of Agent A was completed.

[0138]

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<< Preparation of 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane: Reducing Agent Solid Fine Particle Dispersion >> 1,1-bis (2-hydroxy- 3,5-dimethylphenyl) -3,5,5-trimethylhexane
25 g of a 20% aqueous solution of MP-203 manufactured by MP Polymer Co., Ltd., 0.1 g of Safinol 104E manufactured by Nissin Chemical Co., Ltd., 2 g of methanol and water
48 ml was added, stirred well, and left as a slurry for 3 hours. Thereafter, 360 g of 1 mm zirconia beads were prepared, put into a vessel together with the slurry, and dispersed for 3 hours with a disperser (1 / 4G sand grinder mill: manufactured by IMEX Co., Ltd.) to prepare a dispersion of solid fine particles of a reducing agent. . The particle size is
80% by weight of the particles were 0.3 μm or more and 1.0 μm or less.

<< Preparation of Solid Fine Particle Dispersion of Polyhalogen Compound >> 4 g of MP-203, an MP polymer manufactured by Kuraray Co., Ltd., and 0.25 g of compound C per 30 g of polyhalogen compound-A
Then, 66 g of water was added and stirred well, and then 200 g of 0.5 mm zirconia silicate beads were prepared and put into a vessel together with the slurry, and then dispersed in a disperser (1 / 16G sand grinder mill: manufactured by Imex Co., Ltd.). The mixture was dispersed for a time to prepare a solid fine particle dispersion. Particle size is 80% by weight of particles 0.3
It was not less than μm and not more than 1.0 μm. Polyhalogen compound-B
A solid fine particle dispersion was prepared in the same manner as for the polyhalogen compound-A, and had the same particle diameter.

<< Preparation of Solid Fine Particle Dispersion of Nucleator >> Table 2
(The chemical structure of nucleating agent 62 is as described above in this specification, and the chemical structure of nucleating agent A is as follows), and 2.5 g of polyvinyl alcohol (Kuraray PVA-217) is used.
g and water (87.5 g) were added, stirred well, and left as a slurry for 3 hours. After that, 240g of 0.5mm zirconia beads were prepared and put into a vessel together with the slurry, and the dispersion machine (1 / 4G
Sand grinder mill: manufactured by Imex Co., Ltd.)
The mixture was dispersed for 10 hours to prepare a solid fine particle dispersion. The particle diameter was such that 80% by weight of the particles were 0.1 μm or more and 1.0 μm or less and the average particle diameter was 0.5 μm.

<< Preparation of Solid Fine Particle Dispersion of Compound Z >> For 30 g of Compound Z, the MP polymer of Kuraray Co., Ltd.
3 g of P-203 and 87 ml of water were added, stirred well, and left as a slurry for 3 hours. Thereafter, a solid fine particle dispersion of the compound Z was prepared in the same manner as in the preparation of the reducing agent solid fine particle dispersion. The particle diameter is 80% by weight of the particles is 0.3 μm or more and 1.0
μm or less.

<< Preparation of Emulsion Layer Coating Solution >> The following binder, material and silver halide emulsion A were added to 1 mol of silver of the organic acid silver dispersions A to G prepared above, and water was added. In addition, an emulsion layer coating solution was used (the kind of the organic acid silver dispersion used is shown in Table 2). After completion, vacuum degassing -350mmHg
For 60 minutes. The coating solution has a pH of 7.7 and a viscosity of 25 ° C.
Was 45 cp.

Binder; Luckstar 3307B 397 g as solid content (manufactured by Dainippon Ink and Chemicals, Inc .; glass transition temperature of 17 ° C. with SBR latex) 1,1-bis (2-hydroxy-3,5-dimethylphenyl)- 3,5,5-trimethylhexane 149 g as solid content Polyhalogen compound-A 43.5 g as solid content Polyhalogen compound-B 13.5 g as solid content Sodium ethylthiosulfonate 0.30 g Benzotriazole 1.04 g Polyvinyl alcohol (Kuraray Co., Ltd.) 10.8 g 6-iso-propylphthalazine 12.8 g Sodium dihydrogen orthophosphate dihydrate 0.37 g Compound Z 9.7 g as solids Nucleating agent Kind shown in Table 2. However, the amount is 0.03 mol as a solid content. The coating amount at which the optical density of Dye A 783 nm becomes 0.3 (0.37 g as a standard) 0.06 mol as a silver halide emulsion A Ag amount 2.0 g of compound C 2.0 g of compound C as a preservative in the coating solution of compound A 40 ppm (2.5 mg / m ² as coating amount) 2 wt% in methanol as methanol solvent 1 wt% in ethanol as ethanol solvent (The glass transition temperature of the coating film was 17 ° C.)

[0145]

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<< Preparation of Coating Solution for Emulsion Lower Layer Protective Layer >> Polymer latex solution of methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%) (The glass transition temperature of the copolymer is 46 ° C (calculated value),
21.5% as a solid content concentration, the compound D was a glass transition temperature of the added coating solution of 15% relative to the polymer latex and 24 ° C.) of H ₂ O was added to 943g as coalescent, a compound E 1.6
2g, matting agent (polystyrene particles, average particle size 7μm) 1.98
g and polyvinyl alcohol (Kuraray Co., Ltd., PVA-23
5) 29.4 g was added, and further H ₂ O was added to prepare a coating solution. (Compound A as a preservative was 75 ppm in the coating solution (1.0 mg / m ² as coating amount), and each contained 2 wt% of a methanol solvent.) After completion, deaeration under reduced pressure was performed at -400 mmHg for 60 minutes. The coating solution had a pH of 5.5 and a viscosity of 45 cp at 25 ° C.

<< Preparation of Coating Solution for Emulsion Surface Upper Layer Protective Layer >> Polymer latex solution of methyl methacrylate / styrene / 2-ethylhexyl acrylate / 2-hydroxyethyl methacrylate / acrylic acid = 58.9 / 8.6 / 25.4 / 5.1 / 2 (wt%) (The glass transition temperature of the copolymer is 46 ° C (calculated value),
H ₂ O was added to 649 g of a solid content concentration of 21.5%, Compound D was added as a film-forming aid to the polymer latex at 15%, and the glass transition temperature of the coating solution was set to 24 ° C.), and carnava wax (Chukyo Yushi ( Co., Ltd., Cellsol 524) 30 wt% solution
6.30 g, Compound C 0.23 g, Compound F 7.95 g, Compound G
0.93 g, compound H 1.8 g, matting agent (polystyrene particles, average particle diameter 7 μm) 1.18 g and polyvinyl alcohol (Kuraray Co., Ltd., PVA-235) 12.1 g, and further H ₂ O, A coating solution was prepared. (Compound A as a preservative
Was completed at 70 ppm (a coating amount of 2.6 mg / m ² ), and each contained 1.5 wt% of a methanol solvent. After completion, deaeration under reduced pressure was performed at −400 mmHg for 60 minutes. The coating solution had a pH of 2.8 and a viscosity of 30 cp at 25 ° C.

[0148]

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<< Preparation of PET Support with Back / Undercoat Layer >> (1) Preparation of Support IV = 0.66 (phenol / tetrachloroethane = 6/4) using terephthalic acid and ethylene glycol according to a conventional method. (Measured at 25 ° C. in a weight ratio) of polyethylene terephthalate. After pelletizing this, it was dried at 130 ° C for 4 hours, melted at 300 ° C, extruded from a T-die, and quenched,
An unstretched film having a thickness of 120 μm after heat setting was prepared. Using rolls with different peripheral speeds,
The film was longitudinally stretched 3.3 times and then stretched 4.5 times with a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After that, it was heat-set at 240 ° C. for 20 seconds and relaxed 4% in the lateral direction at the same temperature. Then, after slitting the chuck part of the tenter, knurling is performed on both ends, and 4.8 kg / cm ²
Rolled up. In this way, width 2.4m, length 3500m,
A roll having a thickness of 120 μm was obtained.

(2) Preparation of undercoat layer and back layer (1) First undercoat layer A coating solution having the composition shown below was applied onto a support so as to have a composition of 6.2 cc / m ^2, and was applied at 125 ° C. for 30 seconds. It was dried at 150 ° C. for 30 seconds and at 185 ° C. for 30 seconds.

Latex-A 280 g KOH 0.5 g Polystyrene fine particles (average particle size: 2 μm) 0.03 g Cyanuric chloride 1.8 g Distilled water Amount that totals 1000 g

(2) Second layer of undercoat A coating solution having the composition shown below was applied on the first layer of undercoat at a concentration of 5.5 cc / m ^2, and was applied at 125 ° C. for 30 seconds, 150 ° C. for 30 seconds, 170 ° C. ° C
For 30 seconds.

Gelatin 10 g Acetic acid (20% aqueous solution) 10 g Compound-Bc-A 0.04 g Methylcellulose (2% aqueous solution) 25 g Polyethyleneoxy compound 0.3 g Distilled water Amount that totals 1000 g

(3) Back first layer A coating solution having the composition shown below was applied to the surface of the support on the side opposite to the undercoat layer on which the corona discharge treatment was performed so as to have a flow rate of 13.8 cc / m ^2. It dried at 30 degreeC for 30 second, 150 degreeC for 30 second, and 185 degreeC for 30 second.

Julimer ET410 (30%) 23 g Gelatin 5.28 g Compound-Bc-A 0.02 g Dye-Bc-A 0.88 g Polyoxyethylene phenyl ether 1.7 g Sumitex Resin M-3 (8% aqueous solution) 15 g (Water-soluble melamine Compound, manufactured by Sumitomo Chemical Co., Ltd.) FS-10D (Sb-doped SnO2 aqueous dispersion, manufactured by Ishihara Sangyo Co., Ltd.) 24 g Polystyrene fine particles (average particle size: 2 μm) 0.03 g Distilled water Amount that totals 1000 g

(4) Back second layer A coating solution having the composition shown below was applied on the back first layer to a concentration of 5.5 cc / m ^2, and was applied at 125 ° C. for 30 seconds, 150 ° C. for 30 seconds, 170 ° C. In 3
Dried for 0 seconds.

Julimer ET410 (30%) 57.5 g Polyoxyethylene phenyl ether 1.7 g Sumitex Resin M-3 (8% aqueous solution) 15 g (water-soluble melamine compound, manufactured by Sumitomo Chemical Co., Ltd.) Cellosol 524 (30% aqueous solution) 6.6g Distilled water Total amount of 1000g

(5) Third backing layer The same coating solution as that for the first undercoating layer was applied onto the second backing layer at a concentration of 6.2 cc / m ^2, and was applied at 125 ° C. for 30 seconds, 150 ° C. for 30 seconds, and 185 ° C. ° C
For 30 seconds.

(6) Fourth Back Layer A coating solution having the composition shown below was applied onto the third back layer so as to have a composition of 13.8 cc / m ^2, and was applied at 125 ° C. for 30 seconds, 150 ° C. for 30 seconds, and 170 ° C.
For 30 seconds.

Latex-B 286 g Compound-Bc-B 1.5 g Compound-Bc-C 0.6 g Compound-Bc-D 0.5 g Sumitex Resin M-3 (8% aqueous solution) 195 g (Water-soluble melamine compound, Sumitomo Chemical ( Co., Ltd.) Polymethyl methacrylate (10% aqueous dispersion, average particle size 5 μm) 7.7 g Distilled water Amount that becomes 1000 g in total amount

[0161]

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[0162]Latex-A  90% by weight of core and 10% by weight of shell
Latex core vinylidene chloride / methyl acrylate / methyl meth
Tacrylate / acrylonitrile / acrylic acid = 93/3/3/0.
9 / 0.1 (% by weight) Shell part Vinylidene chloride / methyl acrylate / methyl
Methacrylate / acrylonitrile / acrylic acid = 88/3/3 /
3/3 (% by weight) Weight average molecular weight 38000Latex-B  Methyl methacrylate / styrene / 2-ethylhexylaku
Relate / 2-hydroxyethyl methacrylate / acryl
Acid = 59/9/26/5/1 (wt% copolymer)

(7) Heat treatment for transport (7-1) Heat treatment PE thus prepared with a back / undercoat layer
The T support was placed in a heat treatment zone having a total length of 200 m set at 160 ° C. and transported at a tension of 2 kg / cm ² and a transport speed of 20 m / min. (7-2) Post-heat treatment After the above heat treatment, post-heat treatment was carried out by passing through a zone at 40 ° C for 15 seconds, and the film was wound up. The winding tension at this time is 10
kg / cm ² .

<< Preparation of Photothermographic Material >> On the undercoat layer of the PET support on which the first undercoat layer and the second undercoat layer are coated, the pattern in the specification of Japanese Patent Application No. 10-292849 is disclosed. Using the slide beat coating method disclosed in No. 1, the emulsion layer coating solution was coated so that the coated silver amount was 1.5 g / m ² . Further, the emulsion layer lower layer protective layer coating solution was coated simultaneously with the emulsion coating solution so that the solid content of the polymer latex was 1.31 g / m ² . Thereafter, the above-mentioned coating liquid for the upper protective layer on the emulsion surface was applied thereon so that the coating amount of the solid content of the polymer latex was 3.02 g / m ² , thereby producing a photothermographic material (sample). Drying at the time of coating is carried out at a constant bulb process and a deceleration process at a dry bulb temperature of 70 to 75 ° C and a dew point of 8 to 2
In a range of 5 ° C. and a liquid film surface temperature of 35 to 40 ° C., a horizontal drying zone (the support is 1.5 ° to 3 ° with respect to the horizontal direction of the coating machine)
Angle). Winding after drying, temperature 25 ± 5 ℃,
It was performed under the condition of a relative humidity of 45 ± 10%, and the outer shape was selected as the outer shape in accordance with the subsequent processing form (Em outer winding). The wrapping humidity of the photosensitive material was set to 20 to 40% (measured at 25 ° C.). The film surface pH on the image forming side of the obtained photothermographic material was 5.0 and the Beck smoothness was 850 seconds. The film surface pH on the opposite side was 5.9 and the Beck smoothness was 560 seconds. The samples used for the evaluation (both photographic performance and surface state) were applied after forced evacuation of the emulsion layer coating solution at 25 ° C. for 6 hours after decompression under forced conditions.

<< Evaluation of Photographic Performance >> (Exposure Processing) The obtained photothermographic material was subjected to a beam diameter (FWHM of 1/2 of beam intensity) of 12.56 μm and a laser output of 50 m.
W, using a single-channel cylindrical inner surface type laser exposure device equipped with a semiconductor laser with an output wavelength of 783 nm, adjust the exposure time by changing the number of rotations of the mirror, adjust the exposure amount by changing the output value, 2 Exposure was performed in × 10 ⁻⁸ seconds. The overlap coefficient at this time was set to 0.449. (Heat development treatment) The exposed heat-developable photosensitive material was subjected to heat treatment using a heat developing machine shown in FIG.
A heat development process was performed at 100 ° C. for 5 seconds and a heat development processing unit at 120 ° C. for 20 seconds. The temperature accuracy in the width direction was ± 1 ° C. (Evaluation of photographic performance) Macbeth TD904
The measurement was performed using a densitometer (visible density). The result of the measurement is Dmin,
It was evaluated by Dmax.

<< Evaluation of Coated Surface State >> The surface of the sample was visually observed, and the coated surface state (surface quality) was classified into the following ranks. Of these, those that are practically acceptable are those of the A and B ranks. A rank: good surface condition. B rank: The surface at the center is good, but there are disturbances at both ends of the coated part. Rank C: There are some surface defects (such as coating streaks, generation of aggregates, cracks, and uneven drying) on the entire surface. Rank D: There are significant surface defects (e.g., streaks, generation of aggregates, cracks, uneven drying) on the entire surface.

Table 2 shows the results of the above evaluation for each photothermographic material.

[0168]

[Table 2]

The heat-developable image recording material of the present invention has a Dmin
And the surface condition is good. Dmax is higher when the compounds represented by the general formulas (1) to (3) (nucleating agent 62) preferably used in the present invention are used than the formylhydrazine-based compound (nucleating agent A) as the nucleating agent. . Organic acid silver dispersion C prepared by adding the third component at a low temperature
To E and the organic acid silver dispersions F and G in which cold water of 10 ° C. was supplied to the heat exchanger to further lower the temperature immediately after the reaction solution can reduce the average particle size. The material is particularly excellent in surface condition. On the other hand, the organic acid silver dispersion A prepared by the conventional production method has a slightly larger average particle size and is polydisperse as compared with the organic acid silver dispersion used in the present invention. The light-sensitive material was inferior in both planarity and Dmin to the light-sensitive material of the present invention. From the above, the effect of the present invention is clear.

<Example 2> (Preparation of PET support) Terephthalic acid and ethylene glycol
Of intrinsic viscosity IV = 0.66 (measured in phenol / tetrachloroethane = 6/4 (weight ratio) at 25 ° C.) according to a conventional method.
I got After pelletizing this, dried at 130 ° C for 4 hours,
After being melted at 300 ° C., it was extruded from a T-shaped stand and quenched to prepare an unstretched film having a thickness of 175 μm after heat fixing. This was longitudinally stretched 3.3 times using rolls having different peripheral speeds, and then laterally stretched 4.5 times using a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After this,
After heat setting at 240 ° C. for 20 seconds, it was relaxed 4% in the lateral direction at the same temperature. Then, after slitting the chuck portion of the tenter, knurling was performed on both ends and wound at 4 kg / cm ² to obtain a roll having a thickness of 175 μm.

(Surface Corona Treatment) Using a solid state corona treatment machine 6KVA model manufactured by Pillar Co., both surfaces of the support were treated at room temperature at 20 m / min. From the current and voltage readings at this time, it was found that the support was treated at 0.375 kV · A · min / m ² . At this time, the processing frequency was 9.6 kHz, and the gap clearance between the electrode and the dielectric roll was 1.6 mm.

(Preparation of Undercoating Support) (1) Preparation of Undercoating Layer Coating Formulation (1) (for undercoating layer on photosensitive layer side) Pesresin A-515GB (30 wt% solution) manufactured by Takamatsu Yushi Co., Ltd. 234 g Polyethylene glycol Monononylphenyl ether (average ethylene oxide number = 8.5) 10wt% solution 21.5g Soken Chemical Co., Ltd. MP-1000 (polymer fine particles, average particle size 0.4μm) 0.91g distilled water 744ml prescription (2) (back side first layer) Butadiene-styrene copolymer latex 158 g (solid content 40 wt%, butadiene / styrene weight ratio = 32/68) 2,4-dichloro-6-hydroxy-S-triazine sodium salt 8 wt% aqueous solution 20 g sodium laurylbenzenesulfonate 1 wt% aqueous solution of 10 ml distilled water 854 ml Formula (3) (for the second layer on the back side) SnO ₂ / SbO (9/1 weight ratio, average particle size 0.038 μm, 17 wt% dispersion) 84 g gelatin (10% aqueous solution) 89.2g Shin-Etsu Chemical Co., Ltd. Metroose TC-5 (2% aqueous solution) 8.6 g MP-1000 (polymer fine particles) manufactured by Soken Chemical Co., Ltd. 0.01 g 1 wt% aqueous solution of sodium dodecylbenzenesulfonate 10 ml NaOH (1%) 6 ml Proxel (manufactured by ICI) 1 ml Distillation 805 ml of water

(Preparation of Undercoat Support) The above thickness of 175 μm
After performing the above-described corona discharge treatment on both surfaces of the biaxially stretched polyethylene terephthalate support, the undercoat coating solution formulation (1) was coated on one surface (photosensitive layer surface) with a wire bar at a wet application amount of 6.6 ml / m ² ( (Per side) and dried at 180 ° C for 5 minutes. Then, apply the undercoating coating solution formulation (2) on the back surface (back surface) with a wire bar so that the wet application amount is 5.7 ml / m ^2. coated and dried 5 minutes at 180 ° C., further back surface (back surface) in the undercoat coating liquid formulation (3) for 6 minutes in the coating to 180 ° C. as the amount of wet coating with a wire bar is 7.7 ml / m ² After drying, an undercoat support was prepared.

(Preparation of Back Surface Coating Solution) (Preparation of Solid Precursor Dispersion (a) of Base Precursor) 64 g of base precursor compound I, 28 g of diphenyl sulfone, and 10 g of Demol N surfactant manufactured by Kao Corporation are distilled. Mix with 220 ml of water and mix the mixture with a sand mill (1/4 Gallo
The beads were dispersed using an n-sand grinder mill (manufactured by Imex Co., Ltd.) to obtain a solid precursor dispersion (a) of a base precursor compound having an average particle diameter of 0.2 μm.

(Preparation of Dye Solid Fine Particle Dispersion) 9.6 g of cyanine dye compound J and 5.8 g of sodium P-dodecylbenzenesulfonate were mixed with 305 ml of distilled water, and the mixture was subjected to a sand mill (1/4 Gallon sand grinder mill, Using IMEX Co., Ltd.) and dispersing the beads, average particle diameter
A 0.2 μm dispersion of solid dye fine particles was obtained.

(Preparation of Coating Solution for Antihalation Layer) 17 g of gelatin, 9.6 g of polyacrylamide, 70 g of solid fine particle dispersion (a) of the above base precursor, 56 g of the above solid fine particle dispersion of dye, and polymethyl methacrylate fine particles (average particle size of 6.5) μm), 1.5 g of benzoisothiazolinone, 2.2 g of sodium polyethylene sulfonate, 0.2 g of blue dye compound K, and 844 ml of water were mixed to prepare an antihalation layer coating solution.

(Preparation of Back Surface Protective Layer Coating Solution)
℃, gelatin 50g, polystyrene sodium sulfonate 0.2g, N, N-ethylenebis (vinylsulfone acetamide) 2.4g, sodium t-octylphenoxyethoxyethaneethanesulfonate 1g, benzoisothiazolinone 30mg, N-perfluoro Octylsulfonyl-N-propylalanine potassium salt 37 mg, polyethylene glycol mono (N-perfluorooctylsulfonyl-N-propyl-
2-aminoethyl) ether [ethylene oxide average polymerization degree 15] 0.15 g, C ₈ F ₁₇ SO ₃ K32 mg, C ₈ F ₁₇ SO ₂ N (C ₃ H ₇ ) (CH ₂ CH
₂ O) ₄ (CH ₂ ) ₄ -SO ₃ Na 64 mg, acrylic acid / ethyl acrylate copolymer (copolymerization weight ratio 5/95) 8.8 g, Aerosol OT (manufactured by American Cyanamid Co.) 0.6 g, flowing The paraffin emulsion was mixed with 1.8 g of liquid paraffin and 950 ml of water to prepare a back surface protective layer coating solution.

<< Preparation of Silver Halide Emulsion 1 >> Distilled water 1421
To the cc was added 8.0 cc of a 1 wt% potassium bromide solution, and 8.2 cc of 1N nitric acid, and a solution obtained by adding 20 g of phthalated gelatin was stirred in a titanium-coated stainless steel reaction bottle while maintaining the solution temperature at 37 ° C. Distilled water was added to 37.04 g of silver nitrate to prepare a solution A diluted to 159 cc, and a solution B of 32.6 g of potassium bromide diluted to a volume of 200 cc with distilled water was prepared. The entire amount of A was added at a constant flow rate over 1 minute. Solution B was added by a controlled double jet method. Thereafter, 30 cc of a 3.5 wt% aqueous hydrogen peroxide solution was added, and 3 wt% of benzimidazole was further added.
36 cc of a 30% aqueous solution was added. After that, solution A2 was again diluted with distilled water to 317.5 cc, and solution B was dissolved with potassium trichloride iridate 3 potassium salt in solution B so that the final concentration was 1 × 10 ^-4 mol per mol of silver. And make the liquid volume 400 c twice that of solution B.
Using the solution B2 diluted with distilled water until c, the entire amount of the solution A2 was added at a constant flow rate over 10 minutes while maintaining the pAg at 8.1 also by the controlled double jet method.
Solution B2 was added by a controlled double jet method. Thereafter, 50 cc of a 0.5 wt% methanol solution of 5-methyl-2-mercaptobenzimidazole was added, the pAg was further increased to 7.5 with silver nitrate, the pH was adjusted to 3.8 with 1N sulfuric acid, stirring was stopped, and sedimentation / A desalting / washing step was performed, 3.5 g of deionized gelatin was added, and 1N sodium hydroxide was added to adjust the pH to 6.0 and a pAg of 8.2 to prepare a silver halide dispersion. The grains in the completed silver halide emulsion were pure silver bromide grains having an average equivalent sphere diameter of 0.053 μm and a variation coefficient of equivalent sphere diameter of 18%. The particle size and the like were measured using an electron microscope.
It was determined from the average of individual particles. The [100] plane ratio of these particles was determined to be 85% using the Kubelka-Munk method.

The emulsion was maintained at 38 ° C. with stirring,
0.035 g of benzoisothiazolinone (3.5 wt% methanol
Liquid dispersion), and after 40 minutes, a solid dispersion of spectral sensitizing dye B
(Aqueous gelatin solution) at 5 × 10^-3Mole, 1
After a minute, the temperature was raised to 47 ° C, and after 20 minutes, benzenethiosulfone
3 x 10 for 1 mol of silver^-FiveAdd mole, and then
2 minutes later, tellurium sensitizer A was added in an amount of 5 × 10^-FiveMole addition
And aged for 90 minutes. Immediately before aging, N, N'-dihydro
5c of a 0.5wt% methanol solution of Xy-N "-diethylmelamine
c, lower the temperature to 31 ° C, and add phenoxyethanol.
5cc of 3.5wt% methanol solution, 5-methyl-2-mercaptoben
を 7 × 10 imidazole per mole of silver^-3 Mol and 1-fe
Nyl-2-heptyl-5-mercapto-1,3,4-triazole
6.4 × 10 per mole of silver^-3Mole and add the halogen
Silver halide emulsion 1 was prepared.

<< Preparation of Silver Halide Emulsion 2 >> In the preparation of silver halide emulsion 1, the liquid temperature at the time of grain formation was changed from 37 ° C. to 50 ° C.
In the same manner, a pure silver bromide cubic grain emulsion having an average equivalent sphere diameter of 0.08 μm and a coefficient of variation of equivalent sphere diameter of 15% was prepared in the same manner. Precipitation / desalting / water washing /
Dispersion was performed. Further, except that the addition amount of the spectral sensitizing dye B was changed to 4.5 × 10 ^-3 mol per mol of silver, the same procedure as in the emulsion 1 was repeated except that the spectral sensitizing dye, the chemical sensitizer and 5-methyl-2-mercaptobenzene were used. Imidazole and 1-phenyl-2-heptyl-5-mercapto-1,3,4-triazole were added to obtain a silver halide emulsion 2.

<< Preparation of Silver Halide Emulsion 3 >> In the preparation of silver halide emulsion 1, the liquid temperature at the time of grain formation was changed from 37 ° C. to 27 ° C.
In the same manner, a pure silver bromide cubic grain emulsion having an average equivalent spherical diameter of 0.038 μm and a coefficient of variation of equivalent spherical diameter of 20% was prepared in the same manner. Precipitation / desalting / water washing /
Dispersion was performed. Further, except that the addition amount of the spectral sensitizing dye B was changed to 6 × 10 ^-3 mol per mol of silver, the same procedure as in the emulsion 1 was repeated except that the spectral sensitizing dye, the chemical sensitizer and the 5-methyl-2-mercaptobenzene were used. Imidazole and 1-phenyl-2-heptyl-5-mercapto-1,3,4-triazole were added to obtain a silver halide emulsion 3.

<< Preparation of Mixed Emulsion B for Coating Liquid >> Silver halide emulsion 1 was 70% by weight, silver halide emulsion 2 was 15% by weight,
15% by weight of silver halide emulsion 3 was dissolved, and benzothiazolium iodide was dissolved in a 1% by weight aqueous solution at a concentration of 7 × 10 5 per mole of silver.
^-3 mol was added.

<< Preparation of 25 wt% Dispersion of Reducing Agent >> 1,1-bis
10 kg of (2-hydroxy-3,5-dimethylphenyl) -3,5,5-trimethylhexane and modified polyvinyl alcohol (Kuraray
16 kg of water to 10 kg of a 20 wt% aqueous solution of Poval MP203 manufactured by Co., Ltd.
Was added and mixed well to form a slurry. The slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 3 hours and 30 minutes, and then benzoisothiazolinone sodium salt 0.2 g and water were added to adjust the concentration of the reducing agent to 25 wt% to obtain a reducing agent dispersion. The reducing agent particles contained in the thus obtained reducing agent dispersion had a median diameter of 0.42 μm and a maximum particle diameter of 2.0 μm or less. The resulting reducing agent dispersion was filtered through a polypropylene filter having a pore size of 10.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of a 10 wt% dispersion of a mercapto compound >> 5 kg of 1-phenyl-2-heptyl-5-mercapto-1,3,4-triazole and modified polyvinyl alcohol (Kuraray)
8.3 kg of water was added to 5 kg of a 20 wt% aqueous solution of Poval MP203 manufactured by Co., Ltd., and mixed well to form a slurry. The slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by Imex Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 6 hours, and then water was added to reduce the concentration of the mercapto compound. It was adjusted to 10 wt% to obtain a mercapto dispersion. The mercapto compound particles contained in the mercapto compound dispersion thus obtained had a median diameter of 0.40 μm and a maximum particle diameter of 2.0 μm or less. The obtained mercapto compound dispersion was filtered through a polypropylene filter having a pore size of 10.0 μm to remove foreign substances such as dust, and stored. Immediately before use, the mixture was again filtered through a polypropylene filter having a pore size of 10 μm.

<< Preparation of 20 wt% dispersion of organic polyhalogen compound-1 >> 5 kg of tribromomethylnaphthyl sulfone and modified polyvinyl alcohol (Poval MP20 manufactured by Kuraray Co., Ltd.)
3) 2.5 kg of a 20 wt% aqueous solution, 213 g of a 20 wt% aqueous solution of sodium triisopropylnaphthalenesulfonate, and 10 kg of water
Was added and mixed well to form a slurry. This slurry was sent by a diaphragm pump and dispersed in a horizontal sand mill (UVM-2: manufactured by IMEX Co., Ltd.) filled with zirconia beads having an average diameter of 0.5 mm for 5 hours, and then 0.2 g of benzoisothiazolinone sodium salt was added. Water was added to adjust the concentration of the organic polyhalogen compound to 20% by weight to obtain an organic polyhalogen compound dispersion. Organic polyhalogen compound particles contained in the polyhalogen compound dispersion thus obtained had a median diameter of 0.36 μm and a maximum particle diameter of 2.0 μm or less. The resulting organic polyhalogen compound dispersion has a pore size
Perform filtration with a 3.0 μm polypropylene filter,
Foreign matter such as dust was removed and stored.

<< Preparation of 25% by weight dispersion of organic polyhalogen compound-2 >> 20% by weight dispersion of organic polyhalogen compound-
Same as 1, except that tribromomethylnaphthyl sulfone
Tribromomethyl (4- (2,4,6-
Trimethylphenylsulfonyl) phenyl) sulfone 5k
g, disperse, and this organic polyhalogen compound is 25 wt%
And filtered. The organic polyhalogen compound particles contained in the organic polyhalogen compound dispersion thus obtained had a median diameter of 0.38 μm and a maximum particle diameter of 2.0 μm or less. The obtained organic polyhalogen compound dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored.

<< Preparation of 30% by weight dispersion of organic polyhalogen compound-3 >> 20% by weight dispersion of organic polyhalogen compound
Same as 1, except that tribromomethylnaphthyl sulfone
Instead of 5 kg, 5 kg of tribromomethylphenylsulfone was used, 5 kg of a 20 wt% aqueous solution of MP203 was dispersed, diluted to 30 wt% of this organic polyhalogen compound, and filtered. Organic polyhalogen compound particles contained in the organic polyhalogen compound dispersion thus obtained have a median diameter of 0.
It was 41 μm and the maximum particle size was 2.0 μm or less. The obtained organic polyhalogen compound dispersion was filtered with a polypropylene filter having a pore size of 3.0 μm to remove foreign substances such as dust, and stored. After storage, it was stored at 10 ° C or less until use.

<< Preparation of 10 wt% methanol solution of phthalazine compound >> 10 g of 6-isopropylphthalazine was added to methanol 9
It was dissolved in 0 g and used.

<< Preparation of 20 wt% Dispersion of Pigment >> CI Pigment
To 64 g of Blue 60 and 6.4 g of Demol N manufactured by Kao Corporation, 250 g of water was added and mixed well to form a slurry. 800 g of zirconia beads having an average diameter of 0.5 mm were prepared, put into a vessel together with the slurry, and dispersed with a dispersing machine (1 / 4G sand grinder mill: manufactured by IMEX Co., Ltd.) for 25 hours to obtain a pigment dispersion. The pigment particles contained in the pigment dispersion thus obtained had an average particle size of 0.21 μm.

<< Preparation of 40 wt% of SBR latex >> Ultrafiltration (U
F) The purified SBR latex was obtained as follows. S below
BF-refining module FS03-FC-FUY03A1 (Daisen membrane
The system was diluted and purified to an ionic conductivity of 1.5 mS / cm using Sanyo Chemical Co., Ltd.
It was added to be 2 wt%. Further, using NaOH and NH ₄ OH, Na ⁺
It was added so that ion: NH ₄ ⁺ ion = 1: 2.3 (molar ratio) and adjusted to pH 8.4. The latex concentration at this time is 4
It was 0 wt%. (SBR latex: -St (68) -Bu (29) -AA (3)-latex) (St: styrene, Bu: butadiene, AA: acrylic acid) Average particle size 0.1 μm, concentration 45%, 25 ° C 60 Equilibrium moisture content at% RH
0.6 wt%, ionic conductivity 4.2 mS / cm (Measurement of ionic conductivity using a conductivity meter CM-30S manufactured by Toa Denpa Kogyo Co., Ltd., measuring a latex stock solution (40%) at 25 ° C.), pH 8.2

<< Preparation of Coating Solution for Emulsion Layer (Photosensitive Layer) >> 1.1 g of a 20 wt% aqueous dispersion of the pigment obtained above and 103 g of silver organic acid dispersions A to G as in Example 1 were used. The types are shown in Table 3) and 2 of polyvinyl alcohol PVA-205 (manufactured by Kuraray Co., Ltd.).
5 g of a 0 wt% aqueous solution, 25 g of the above 25 wt% reducing agent dispersion, and organic polyhalogen compound dispersion-1, -2, -3 in a total amount of 5: 1: 3 (weight ratio) of 1
6.3 g, mercapto compound 10% dispersion 6.2 g, ultrafiltration (U
F) 106 g of purified and pH-adjusted SBR latex (40 wt%) and 16 ml of a 10 wt% methanol solution of a phthalazine compound were added,
10 g of the silver halide mixed emulsion B was mixed well to prepare a coating solution for the emulsion layer, and the solution was directly sent to a coating stand at 70 ml / m ² and coated. The viscosity of the emulsion layer coating solution was 85 [mPa · s] at 40 ° C. (No. 1 rotor, 60 rpm) as measured by a B-type viscometer of Tokyo Keiki. The viscosity of the coating solution at 25 ° C. using a Rheometrics Far East Co., Ltd.
1500, 22 at 1, 1, 10, 100, 1000 [1 / sec]
The values were 0, 70, 40, and 20 [mPa · s].

<< Preparation of Emulsion Surface Intermediate Layer Coating Solution >> 772 g of a 10 wt% aqueous solution of polyvinyl alcohol PVA-205 (manufactured by Kuraray Co., Ltd.)
5.3 g of 20 wt% dispersion of pigment, aerosol in 226 g of methyl methacrylate / styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymer weight ratio 64/9/20/5/2) latex 27.5 wt% liquid OT a 5 wt% aqueous solution (manufactured by American Cyanamid Co.) 2 ml, and 20 wt% aqueous solution of phthalic acid diammonium salt 10.5 ml, an intermediate layer coating solution by adding water to a total amount of 880 g, to 10 ml / m ² The solution was sent to the coating table. The viscosity of the coating solution is B type viscometer 40
It was 21 [mPa · s] at ° C (No. 1 rotor, 60 rpm).

<< Preparation of Coating Solution for First Layer of Emulsion Surface Protective Layer >> 64 g of inert gelatin was dissolved in water, and methyl methacrylate was added.
/ Styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymer weight ratio 64/9/20
/ 5/2) 80g of latex 27.5wt% liquid, 64ml of 10wt% methanol solution of phthalic acid, 74m of 10wt% aqueous solution of 4-methylphthalic acid
l, 28 ml of 1N sulfuric acid, 5 ml of a 5 wt% aqueous solution of Aerosol OT (manufactured by American Cyanamid), phenoxyethanol
0.5 g and benzoisothiazolinone 0.1 g were added, and water was added to make a total amount of 750 g to make a coating solution.A mixture of 4 wt% chrome alum 26 ml with a static mixer immediately before coating was added to 18.6 ml / m ² . The solution was sent to the coating table. The viscosity of the coating solution is B type viscometer 40 ° C (No.1 rotor, 60r
pm) was 17 [mPa · s].

<< Preparation of Coating Solution for Second Layer of Emulsion Surface Protective Layer >> 80 g of inert gelatin was dissolved in water, and methyl methacrylate was added.
/ Styrene / butyl acrylate / hydroxyethyl methacrylate / acrylic acid copolymer (copolymer weight ratio 64/9/20
/ 5/2) 102g of latex 27.5wt% liquid, 5wt of N-perfluorooctylsulfonyl-N-propylalanine potassium salt
% Solution, 32 ml of a 2 wt% aqueous solution of polyethylene glycol mono (N-perfluorooctylsulfonyl-N-propyl-2-aminoethyl) ether [ethylene oxide average polymerization degree = 15], Aerosol OT (American cyanamide) 23%, 4 g of polymethyl methacrylate fine particles (average particle diameter 0.7 μm), 21 g of polymethyl methacrylate fine particles (average particle diameter 6.4 μm), 4-methylphthalic acid 1.6 g
g, phthalic acid 8.1 g, 1N sulfuric acid 44 ml, water was added to benzoisothiazolinone 10 mg to a total amount of 650 g, and immediately before application of 445 ml of an aqueous solution containing 4 wt% chrome alum and 0.67 wt% phthalic acid. Was mixed with a static mixer to give a coating solution for the surface protective layer, and the solution was fed to a coating table so as to have a concentration of 8.3 ml / m ² . The viscosity of the coating liquid is 40 ° C with a B-type viscometer
(No. 1 rotor, 60 rpm) and 9 [mPa · s].

<< Preparation of heat-developable image recording material >> On the back surface side of the undercoating support, an antihalation layer coating solution was applied so that the solid content of the solid fine particle dye was 0.04 g / m ² .
The coating amount of the back surface protective layer was 1.7 g / m ² of gelatin.
And then dried to form an antihalation back layer. On the side opposite to the back side, from the undercoat side, the emulsion layer (silver halide coated silver amount 0.14 g / m ² ), the intermediate layer, the protective layer first layer, and the protective layer second layer in the order of the slide bead coating method. Simultaneous multilayer coating was performed to prepare a sample of the photothermographic material. The samples used in this evaluation (both photographic performance and surface state) were prepared under the following conditions:
What was applied after elapse of 6 hours at ℃ was used. The application is performed at a speed of 160 m / min, the distance between the tip of the coating table and the support is adjusted to 0.14 to 0.28 mm, and the application width is adjusted by 0.5 mm for each of the left and right sides with respect to the width of the application liquid slit. The pressure in the decompression chamber was set 392 Pa lower than the atmospheric pressure. At that time, the handling and the temperature and humidity were controlled so that the support was not charged, and the charge was removed by ion wind immediately before coating. In the subsequent chilling zone, the dry bulb temperature is 18 ° C,
The coating solution is cooled by blowing air with a wet-bulb temperature of 12 ° C for 30 seconds, and then drying air with a dry-bulb temperature of 30 ° C and a wet-bulb temperature of 18 ° C in a helical floating type drying zone. Was sprayed for 200 seconds, passed through a drying zone at 70 ° C. for 20 seconds, passed through a drying zone at 90 ° C. for 10 seconds, and then cooled to 25 ° C. to evaporate the solvent in the coating solution. The average wind speed of the air blown to the coating liquid film surface in the chilling zone and the drying zone is 7 m / sec.
Met.

[0196]

Embedded image

<< Evaluation of photographic performance >> After exposing the heat-developable image recording material with a laser sensitometer (details described below), the image recording material was processed at 118 ° C. for 5 seconds, and then at 122 ° C. for 16 seconds (heat development).
Then, the obtained image was evaluated by a Macbeth TD904 densitometer (visible density). The measurement results were evaluated using Dmin and Dmax. Laser sensitometer: 35 mW output two 660nm diode laser combined single mode Gaussian beam spot 1 / e ² feed in the sub-scanning direction by 100 [mu] m 25 [mu] m pitch, writing 4 times one pixel

<< Evaluation of Coated Surface State >> The surface of each sample was visually observed in the same manner as in Example 1 and classified into ranks. Table 3 shows the results of the above evaluations for each heat-developable image recording material.
Shown in

[0199]

[Table 3]

As in Example 1, it was confirmed that the heat-developable image recording material of the present invention had a low Dmin and a good surface condition.

[0201]

According to the present invention, there is provided a heat-developable image recording material which can be applied in water-based form, which is advantageous in terms of environment and cost, has good coated surface quality, low fog and high blackening density. It became possible to do.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating a method for preparing a non-photosensitive organic silver salt used in the present invention.

FIG. 2 is a schematic view showing one configuration example of an apparatus used for preparing a non-photosensitive organic silver salt used in the present invention.

FIG. 3 is a schematic view showing one configuration example of an apparatus used for preparing a non-photosensitive organic silver salt used in the present invention.

FIG. 4 is a side view showing the configuration of the heat developing machine used in the embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Closed mixer 2 Heat exchanger A Additive component 1 B Additive component 2 C Additive component 3 D Product liquid (before heat exchange) E Product liquid (after heat exchange) 11 Tank for additive component 1 12 Tank for additive component 2 13 Flow meter for additive component 1 14 Flow meter for additive component 2 15 Pump for additive component 1 16 Pump for additive component 2 17 Pump for circulation of product liquid 18 Closed mixer 19 Heat exchanger 20 Tank for product liquid 31 For additive component 1 Tank 32 Tank for additive component 2 33 Flow meter for additive component 1 34 Flow meter for additive component 2 35 Pump for additive component 1 36 Pump for additive component 2 37 Pump for additive component 3 38 Closed mixer 39 Heat exchanger 40 Generation Liquid tank 41 Additive 3 tank 42 Additive 2 flow meter 50 Thermally developed image recording material 51 Loading roller pair 52 Loading roller pair 53 Roller 54 Smooth Surface 55 Heater 56 Guide plate

Claims (6)

[Claims] 1. A heat-developable image recording material having a reducing agent, a binder and non-photosensitive organic silver salt particles on a support, wherein the non-photosensitive organic silver salt particles are water or a mixture of water and an organic solvent. A solution containing silver ions as a solvent, water,
A heat-developable image recording material, which is prepared by mixing and reacting a solution of an alkali metal salt of a fatty acid using an organic solvent or a mixture of water and an organic solvent in a closed mixing means. 2. The method according to claim 1, wherein the non-photosensitive organic silver salt particles are prepared by a method comprising cooling the reacted reaction mixture after performing the reaction in the liquid mixing means. The heat-developable image recording material according to the above. 3. The heat-developable image recording material according to claim 1, further comprising a photosensitive silver halide. 4. The method according to claim 1, wherein a polymer latex having a glass transition temperature of −30 ° C. to 40 ° C. is used as 50% by weight or more of the binder in the image forming layer having the non-photosensitive organic silver salt particles. 4. The heat-developable image recording material according to any one of 3. 5. The heat-developable image recording according to claim 1, wherein at least one nucleating agent is contained in at least one of the image forming layers on the support. material. 6. The nucleating agent is a substituted alkene derivative represented by the following formula (1), a substituted isoxazole derivative represented by the following formula (2), or a specific acetal compound represented by the following formula (3): The heat-developable image recording material according to claim 1, wherein the material is at least one compound selected from the group consisting of: Embedded image [In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent, and Z represents an electron-withdrawing group or a silyl group. In the formula (1), R ¹ and Z, R ² and R ³ ,
R ¹ and R ² , and R ³ and Z may combine with each other to form a cyclic structure. In the formula (2), R ⁴ represents a substituent. In the formula (3), X and Y each independently represent a hydrogen atom or a substituent, and A and B each independently represent
Represents an alkoxy group, an alkylthio group, an alkylamino group, an aryloxy group, an arylthio group, an anilino group, a heterocyclic oxy group, a heterocyclic thio group or a heterocyclic amino group. In the formula (3), X and Y, and A and B may be bonded to each other to form a cyclic structure. ]