WO2007145094A1

WO2007145094A1 - Thermally developable photosensitive material

Info

Publication number: WO2007145094A1
Application number: PCT/JP2007/061274
Authority: WO
Inventors: Hideki Komatsu
Original assignee: Konica Minolta Medical & Graphic, Inc.
Priority date: 2006-06-16
Filing date: 2007-06-04
Publication date: 2007-12-21
Also published as: JPWO2007145094A1

Abstract

A thermally developable photosensitive material that simultaneously excels in pre-processing storability and developability. There is provided a thermally developable photosensitive material having a support and, superimposed thereon, an image forming layer containing non-photosensitive aliphatic carboxylic acid silver salt grains, photosensitive silver halide grains, a silver ion reducing agent and a binder, characterized in that the amount of binder as a constituent of the image forming layer is in the range of 25 to 35 mass% based on the total solid content constituting the image forming layer, and that at least one type of binder has a polymerization degree of 1000 to 3000.

Description

Specification

Photothermographic material

Technical field

The present invention relates to a photothermographic material containing a non-photosensitive organic silver salt, photosensitive halogenated silver particles, a binder and a silver ion reducing agent on a support (also simply referred to as a heat-developable material or a photosensitive material). About.

Background art

[0002] Conventionally, in the medical and printing plate making fields, waste liquids resulting from wet processing of image forming materials have been a problem in terms of workability. In recent years, the amount of waste processing liquids has been reduced from the viewpoint of environmental conservation and space saving. It is strongly desired. Therefore, photothermographic materials capable of forming an image by simply applying heat have been put into practical use and are rapidly spreading in the above fields.

The photothermographic material itself has been proposed for a long time (see, for example, Patent Documents 1 and 2).

[0004] This photothermographic material is characterized in that all the materials necessary for the reaction are contained in the film and remain in the film after processing. Many studies have been conducted and reported to achieve both storability and developability. In particular, with regard to the increase in capri during the storage period, there are techniques for bleaching capri nuclei generated during the storage period with polyhalogen compounds (for example, see Patent Document 3) and methods for controlling the Tg and degree of polymerization of the binder. It is effective (for example, refer to Patent Documents 4 to 6). However, the current situation is that each method has a sufficient level of damage to developability and meets the market demands.

Patent Document 1: U.S. Pat.No. 3,152,904

Patent Document 2: U.S. Pat.No. 3,457,075

Patent Document 3: Japanese Patent Laid-Open No. 07-002781

Patent Document 4: Japanese Patent Laid-Open No. 2002-341483

Patent Document 5: Japanese Unexamined Patent Application Publication No. 2002-156727

Patent Document 6: Japanese Patent Laid-Open No. 2004-279500 Disclosure of the invention

Problems to be solved by the invention

[0005] The present invention has been made in view of the above-described background circumstances, and an object thereof is to provide a photothermographic material having both storability before development and developability.

Means for solving the problem

[0006] The above object of the present invention can be achieved by the following configurations.

1. A photothermographic material having an image forming layer containing a non-photosensitive aliphatic carboxylic acid silver salt particle, a photosensitive silver halide particle, a silver ion reducing agent and a polymer binder on the support. The binder amount of the forming layer is 25 to 35% by mass with respect to the total solid content contained in the image forming layer, and the binder contains a polymer having a polymerization degree of 1000 or more and 3000 or less. A photothermographic material.

[0007] 2. An isocyanate compound is added to the image forming layer in a range of more than 0% by mass and 3.5% by mass or less with respect to the noinder amount of the image forming layer 1 The photothermographic material described.

[0008] 3. The photothermographic material according to 1 or 2, wherein the binder has a Tg of 70 to 105 ° C.

[0009] 4. The photothermographic material according to any one of 1 to 3, wherein the image-forming layer contains poly (bullacetal) resin as at least one binder.

[0010] 5. The non-photosensitive aliphatic carboxylic acid silver salt particle force, comprising a silver salt of a fatty acid having a behenic acid content of 70 to 99.99mo 1%, according to any one of 1 to 4, Photothermographic material.

[0011] 6. The photothermographic material according to any one of 1 to 5, wherein the silver ion reducing agent is represented by the following general formula (1):

[0012] [Chemical 1] —General formula (1)

(In the formula, R represents a hydrogen atom or a substituent. R and R each independently represents the number of carbon atoms.

one two Three

Represents 3 to 8 branched alkyl groups. A and A are each independently a hydroxyl group or a reduction or deprotection

1 2

It represents a group capable of forming a hydroxyl group by being protected, and n and m represent an integer of 3 to 5. )

7. The total silver amount of the non-photosensitive aliphatic carboxylic acid silver salt particles and the photosensitive halogenated silver halide particles is 0.8 to 1.5 gZm ² , The thermal image light-sensitive material described.

The invention's effect

[0014] According to the present invention, a photothermographic material having both preservative preservability and developability can be provided.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] The present invention will be described in more detail.

[0016] [Binder]

(Binder for image forming layer)

The binder made of the polymer contained in the image forming layer according to the present invention can carry silver salt, silver halide grains, a reducing agent, and other components. The binder preferably used is transparent or translucent, Generally, it is colorless and includes natural polymers, synthetic polymers and copolymers, and other media for forming a film, for example, those described in paragraph “0069” of JP-A-2001-330918. Among these, particularly preferred examples include high molecular compounds having an acetal group, alkyl methacrylates, aromatic methacrylates, and styrenes. Among such polymers (polymer compounds), it is preferable to use a polymer compound having an acetal group.

[0017] Even a polymer compound having an acetal group is a polyvinyl compound having an acetacetal structure. The power of being setanore is more preferable than S, and in the f row, polybules shown in U.S. Pat.Nos. 2,358,836, 3,003,879, 2,828,204, British Patent 771,155, etc. Acetal can be mentioned. Preferred for the present invention! /! Binders are polyvinyl acetals, particularly preferably polyvinyl butyral, which is preferably used as the main binder of the photosensitive layer. The main binder as used herein refers to “a state in which the polymer occupies 50% by mass or more of the total binder in the image forming layer”. Therefore, other polymers may be blended and used within the range of less than 50% by weight of the total binder!

[0018] The polybutacetal rosin is preferably one that has been synthesized with the power butyl aldehyde and Z or acetoaldehyde, which is synthesized by the aceter Louis reaction of polybulal alcohol and various aldehydes. In particular, the specific force of the acetalized portion of the polybutacetal resin is preferably in the range of 60 to 100% with respect to the total acetalized portion, more preferably 85% or more. When the portion acetalized by aldehyde is 60% or more, the water that causes capri when the obtained polyvinyl acetal resin is hard to absorb moisture becomes the heat-sensitive material of the present invention. It is preferable in order to prevent it from being brought in.

Here, as the aldehyde, any aldehyde that can be acetalized, such as formaldehyde, acetaldehyde, butyraldehyde, propyl aldehyde, and the like may be used. In the present invention, each butyraldehyde is used alone. It is preferable to use a combination of butyraldehyde and acetoaldehyde.

[0020] (Binder content in image forming layer)

The photothermographic material of the present invention is characterized in that the amount of binder in the image forming layer is 25 to 35% by mass with respect to the total solid content contained in the image forming layer. The total solid content contained in the image forming layer includes all binders, non-photosensitive aliphatic carboxylic acid silver salt particles, photosensitive silver halide particles, silver ion reducing agents, etc. contained in the image forming layer. Refers to the solid mass of the material. The material contained in the image forming layer is not particularly limited, and the image forming layer may contain a wide variety of materials as described in the following specification. When two or more types of solder are included, the binder amount in the present invention refers to the sum of the masses of all binders. [0021] (Binder polymerization degree of image forming layer)

The binder contained in the image forming layer according to the photothermographic material of the invention preferably contains at least one polymer having a polymerization degree of 1000 or more and 3000 or less. Furthermore, those having a degree of polymerization in the range of 1250 to 2750 are preferred. Further, when a plurality of binders are used, it is preferable that the polymer having a polymerization degree of 1000 or more and 3000 or less is 20% by mass to 95% by mass (20 to 95% by mass) with respect to the total binder amount. Is preferably 30% by mass or more and 50% by mass or less.

[0022] (Tg of binder of image forming layer)

The photothermographic material of the present invention preferably has a glass transition temperature (Tg) of 70 to 105 ° C. or higher for the noinder used for the image forming layer. Furthermore, the temperature is preferably 70 to 95 ° C. The Tg of the binder is a value that is a measure of the thermal phase transition temperature inside each layer. If the Tg is too low, it promotes changes in photographic performance due to diffusion of the material during storage and changes in density after heat development. Therefore, it is not preferable. On the other hand, if Tg is too high, it is impossible to optimize the fluidity of the resin at a high temperature such as the drying temperature or the heat development temperature. When drying, the drying speed of the coating solution solvent is decreased, and during development, the diffusion speed of the material necessary for image formation is decreased. By optimizing Tg, it is preferable in that sufficient capri density and maximum density can be obtained in image formation. Therefore, in the present invention, the above Tg range is preferable. The Tg of the binder of the present invention can be measured by the so-called DSC method after peeling off the image forming layer of the photothermographic material.

[0023] (Binder for non-image forming layer)

For non-image forming layers (photosensitive layers) such as overcoat layers and undercoat layers, particularly protective layers and backcoat layers, cellulose esters which are polymers having a higher softening temperature, especially triacetyl cellulose. Polymers such as cellulose acetate butyrate are preferred. If necessary, two or more binder resins can be used in combination.

[0024] These binders are used in an effective range to function as a binder for fixing elements of each layer. The effective range can be easily determined by one skilled in the art.

[0025] (Isocyanate compound)

The photothermographic material of the present invention can link binders together by bridging. An isocyanate compound can be contained as a cross-linking agent. The addition amount is preferably in the range of more than 0 and not more than 3.5% by mass with respect to the noinder.

[0026] The isocyanate compound used in the present invention is an isocyanate having at least two isocyanate groups and an adduct thereof (specifically, an aliphatic diisocyanate, cyclic). Aliphatic diisocyanates having a group, benzene diisocyanates, naphthalene diisocyanates, biphenyl diisocyanates, diphenylmethane diisocyanates, triphenylmethane diisocyanates, Examples include triisocyanates, tetraisocyanates, adducts of these isocyanates, and adducts of these isocyanates with divalent or trivalent polyalcohols. As a specific example, an isocyanate compound described on pages 10 to 12 of JP-A-5 6-5535 can be used.

[0027] It should be noted that the adduct of isocyanate and polyalcohol has particularly high ability to improve interlayer adhesion, and prevent layer peeling, image shift and bubble generation. The strong isocyanate may be contained in any part of the photothermographic material. For example, in the support (especially when the support is paper, it can be included in the size composition), image forming layer (photosensitive layer), surface protective layer, intermediate layer, antihalation layer, subbing layer, etc. The power that can be added to any layer on the photosensitive layer side of the support, and the power that can be added to one or more of these layers. many 3.5 mass ^_0/0 is preferably added in the range, than 0 for.

[0028] As the thioisocyanate compounds that can be used, compounds having a thioisocyanate structure corresponding to the above-mentioned isocyanates are also useful.

[0029] (Non-photosensitive aliphatic carboxylic acid silver salt particles)

The non-photosensitive aliphatic carboxylic acid silver salt that can be used in the present invention is relatively stable to light, but is 80 ° C or higher in the presence of exposed photosensitive silver halide and a reducing agent. Is a silver salt that functions as a silver ion supplier when heated further and forms a silver image. The non-photosensitive aliphatic carboxylic acid silver salt can be any aliphatic carboxylate salt that can supply silver ion that can be reduced by a reducing agent! The silver salt of an aliphatic carboxylic acid is particularly a silver salt of a long chain aliphatic carboxylic acid (having 10 to 30, preferably 15 to 28 carbon atoms). preferable. Preferred examples of the aliphatic carboxylic acid silver salt include silver lignocerate, silver behenate, silver arachidate, silver stearate, silver oleate, silver laurate, silver cabrate, silver myristate, silver palmitate, Including strong acid silver and mixtures thereof. In the present invention, the aliphatic carboxylic acid silver salt preferably contains 70 to 99 mol% of silver behenate. Further, it is preferable to contain 80 mol% or more and less than 90 mol% of silver behenate. Further, it is preferable to use an aliphatic carboxylic acid silver salt having a silver uric acid silver content of 2 mol% or less, more preferably 1 mol% or less, and still more preferably 0.1 mol% or less.

[0030] The aliphatic carboxylic acid silver salt of the present invention can be used in a desired amount, but the total silver amount including halogenated silver is preferably 0.8 to 1.5 gZm ^{2 and} more preferably 1.0 to 1. A range of 3 gZm ² is preferred.

[0031] The non-photosensitive aliphatic carboxylic acid silver salt particles of the present invention preferably have a spherical equivalent diameter of 0.05 μm or more and 0.5 m or less. More preferably, it is 0.10 111 or more and 0.5 m or less. The particle size distribution is preferably monodisperse. The monodispersity can be expressed by the standard deviation of the average diameter, and the standard deviation of the aliphatic carboxylic acid silver salt particles of the present invention is preferably 0.3 m or less. Furthermore, it is preferably 0.2 m or less.

[0032] In this case, the particle size and size distribution are calculated from a laser diffraction method, a centrifugal sedimentation light transmission method, an X-ray transmission method, an electrical detection band method, a light shielding method, ultrasonic attenuation spectroscopy, and an image. The particle size distribution can be determined by a generally known particle size distribution measurement method. Among these, for fine particles, a laser diffraction method or a method of calculating from an image is preferable. Further, the aliphatic carboxylic acid silver salt particles dispersed in a liquid preferred by the laser diffraction method can be carried out by a commercially available laser diffraction particle size distribution measuring apparatus.

[0033] Specific examples of the particle size and size distribution measuring method will be shown.

[0034] In a 100 ml beaker, a sample of 0. Olg aliphatic carboxylic acid silver salt particles was taken, 0.1 g of Nonion NS-210 (manufactured by NOF Corporation), 40 ml of water was added, and room temperature was added. The average particle size and standard deviation can be measured with a laser diffraction particle size analyzer SALD-2000 (manufactured by Shimadzu Corporation) using the obtained dispersion.

[0035] The aliphatic carboxylic acid silver salt particles in the present invention may be prepared by reacting a solution containing silver ions with an aliphatic alkanoic acid alkali metal salt solution or suspension. And are preferred. The solution containing silver ions is preferably an aqueous silver nitrate solution, and the aliphatic carboxylic acid metal salt solution or suspension is preferably an aqueous solution or aqueous dispersion. The addition and mixing are preferably performed at the same time. The method of adding to the liquid surface of the reaction bath or the method of adding to the liquid may be used, but the method of adding and mixing in the transfer means is preferred. Mixing in the transfer means means line mixing, and mixing of a solution containing silver ions with an alkali metal salt of an aliphatic carboxylic acid salt or suspension before entering a batch storing a mixture containing reactants. It is preferred to be done ヽ. Any means such as a mechanical mixer such as a homomixer, a static mixer, or a turbulent effect may be used as the stirring means in the mixing section, but it is preferable not to use mechanical stirring. In addition to the solution containing silver ions, aliphatic carboxylic acid alkali metal salt solution or suspension, the mixing in the transfer means includes a third solution such as water or a circulating solution of the mixed solution stored in the batch after mixing. Liquids or suspensions may be mixed.

[0036] Further, in the present invention, the concentration of the aqueous silver nitrate solution is preferably 1 to 15% by mass, and the concentration of the aliphatic carboxylic acid metal salt aqueous solution or the aqueous dispersion is preferably 1 to 5% by mass. Outside the above concentration range, productivity is significantly degraded in the low concentration region, and it is difficult to adjust the particle size and size distribution within the range of the present invention in the high concentration region which is not practical. In addition, when the mixed molar ratio of silver nitrate to the aliphatic carboxylic acid alkali metal salt is preferably in the range of 0.9 to 1.1, the particle size and size distribution should be adjusted within the range of the present invention. In addition, the yield of aliphatic carboxylic acid silver salt is reduced, and the formation of acid silver that causes capri is likely to occur.

[0037] In the present invention, the prepared aliphatic carboxylic acid silver salt is preferably washed with water and then dried from the viewpoint of storage stability. Washing with water is performed mainly to remove unreacted ions, but may be performed with an organic solvent in consideration of the subsequent drying step. The washing with water is preferably performed at 50 ° C or lower. Furthermore, it is preferable to carry out at 30 ° C or less. If it is carried out at 50 ° C. or higher, it is difficult to adjust the particle size and size distribution within the scope of the present invention. The drying is preferably performed at a temperature lower than the phase transition temperature of the aliphatic carboxylic acid silver salt. Furthermore, it is preferable to carry out at 50 ° C or less, and it is preferred to carry out at a low temperature as much as possible! For drying above the phase transition temperature, the particle size and size distribution are It becomes difficult to adjust to the range.

[0038] In the present invention, the preparation of the aliphatic carboxylic acid silver salt is preferably carried out in the absence of photosensitive halogenated silver particles. In the preparation in the presence of photosensitive silver halide silver, it is difficult to adjust the size and size distribution of the aliphatic carboxylic acid silver salt particles within the scope of the present invention because of the compatibility with the capri performance.

[0039] The aliphatic carboxylic acid silver salt of the present invention can be used in a desired amount, but the total silver amount including the halogenated silver is 0.8 to 1.5 g / m ² as the coating amount of the photothermographic material. Further preferably, it is preferably in the range of 1.0 to 1.3 g / m ² .

[0040] (Type of alkali metal salt)

Examples of the types of alkali metal salts that can be used in the present invention include sodium hydroxide, potassium hydroxide, and lithium hydroxide. Of these, it is preferable to use one kind of alkali metal salt such as potassium hydroxide, but it is also preferable to use sodium hydroxide and potassium hydroxide in combination. As a combination ratio, it is preferable that the molar ratio of the above-mentioned hydroxide salt is in the range of 10:90 to 75:25. When used in the above range when reacted with an aliphatic carboxylic acid to form an alkali metal salt of an aliphatic carboxylic acid, the viscosity of the reaction solution can be controlled in a good state.

[0041] (High silveration rate silver salt particles)

The emulsion containing the aliphatic carboxylic acid silver salt grains according to the present invention is a mixture of free aliphatic carboxylic acid and aliphatic carboxylic acid silver salt that forms a silver salt, but the former ratio is the latter. Is low from the viewpoint of image storage stability and the like. That is, the emulsion according to the present invention preferably contains an aliphatic carboxylic acid in an amount of 3 to 1 Omol% with respect to the aliphatic carboxylic acid silver salt grains. The content is particularly preferably 4 to 8 mol%. Specifically, by determining the total aliphatic carboxylic acid amount and the free aliphatic carboxylic acid amount by the following methods, respectively, the aliphatic carboxylic acid silver salt and the free aliphatic carboxylic acid amount and the respective ratios or The ratio of free fatty acids to total aliphatic carboxylic acids will be calculated.

[0042] (Quantification of total aliphatic carboxylic acid content (total of those derived from both the above aliphatic carboxylic acid silver salts and free acids)) (1) About 10 mg of sample (the mass removed when the photosensitive material strength is also peeled off) is accurately weighed and placed in a 20 Oml eggplant type flask.

(2) Add 15 ml of methanol and 3 ml of 4 mol ZL hydrochloric acid and ultrasonically disperse for 1 minute.

(3) Add Teflon (registered trademark) zeolite and reflux for 60 minutes.

(4) After cooling, add 5 ml of methanol as the upper force of the cooling tube, and wash and put the material adhering to the cooling tube into the eggplant type flask (twice).

(5) Extract the resulting reaction solution with ethyl acetate (100 ml of ethyl acetate and 70 ml of water are added to perform separation and extraction twice).

(6) Vacuum dry at room temperature for 30 minutes.

(7) Into a 10 ml volumetric flask, add 1 ml of Benth Anthrone solution as an internal standard (dissolve about 1OO mg of Benzanthrone in toluene and make up to 100 ml with toluene). (8) Dissolve the sample in toluene and put it into the volumetric flask of (7).

(9) Perform gas' chromatography (GC) measurement under the following measurement conditions.

Equipment: HP—5890 + HP—Chem Station

Column: HP— 1 30m X O. 32mm Χ Ο. 25 ^ πι (ΗΡ¾)

Inlet: 250 ° C

Detector: 280 ° C

Oven: 250 ° C—constant

Carrier gas: He

Head pressure: 80kPa

(Quantification of free aliphatic carboxylic acid content)

(1) Weigh accurately about 20 mg of sample, place in a 200 ml eggplant-shaped flask, add 10 ml of methanol, and perform ultrasonic dispersion for 1 minute at 25 ° C (free organic carboxylic acid is extracted).

(2) Filter it and put the filtrate in a 200π eggplant type flask to dryness (free organic carboxylic acid is separated).

(3) Add 15 ml of methanol and 3 ml of 4 mol ZL hydrochloric acid and perform ultrasonic dispersion for 1 minute. (4) Put a Teflon (registered trademark) boiling stone and reflux for 60 minutes.

(5) Add 60 ml of water and 60 ml of ethyl acetate to the resulting reaction solution, Extract the ester cake into the ethyl acetate phase. Extract ethyl acetate twice.

(6) The ethyl acetate phase is dried and vacuum dried for 30 minutes.

(7) Add 1 ml of benzanthrone solution (internal standard: approx. LOOmg of benzanthrone dissolved in toluene to a constant volume of 100 ml) in a 10 ml volumetric flask.

(8) Dissolve (6) with toluene, put into the volumetric flask of (7), and make a constant volume with toluene.

(9) Perform GC measurement under the following measurement conditions.

[0044] Equipment: HP—5890 + HP—Chem Station

Column: HP— 1 30m X O. 32mm Χ Ο. 25 ^ πι (ΗΡ¾)

Inlet: 250 ° C

Detector: 280 ° C

Oven: 250 ° C—constant

Carrier gas: He

Head pressure: 80kPa

(Structure and shape of aliphatic carboxylic acid silver salt)

The shape of the aliphatic carboxylic acid silver salt that can be used in the present invention is not particularly limited and may be any shape such as a needle shape, a rod shape, a flat plate shape, and a flake shape. In the present invention, flake-shaped aliphatic carboxylic acid silver salts and short needle-shaped or rectangular parallelepiped-shaped carboxylic acid silver salts having a major axis / minor axis length ratio of 5 or less are preferably used.

In the present specification, the flaky aliphatic carboxylic acid silver salt is defined as follows. Observe the aliphatic carboxylic acid silver salt with an electron microscope, approximate the shape of the aliphatic carboxylic acid silver salt particle to a rectangular parallelepiped, and define the sides of the rectangular parallelepiped as a, b, c (c is b ) When calculating with the shorter numbers a and b, calculate X as follows.

[0046] x = b / a

In this way, X is obtained from about 200 particles, and when the average value X (average) is obtained, particles satisfying the relationship of x (average) ≥1.5 are defined as flakes. Preferably 30≥x (average) ≥1.5, more preferably 20≥x (average) ≥2.0. Incidentally, an acicular shape is l≤x (average) less than 1.5. [0047] In the flake shaped particle, a can be regarded as the thickness of a tabular particle having a main plane with b and c as sides. The average of a is 0.01 μm or more, 0.23 μ111 or more, more preferably 0.1 m or more and 0.20 m or less. The average of cZb is preferably 1 or more and 6 or less, more preferably 1.05 or more and 4 or less, further preferably 1.1 or more and 3 or less, and particularly preferably 1.1 or more and 2 or less.

[0048] The aliphatic carboxylic acid silver salt according to the present invention may be a crystal particle having a core Z shell structure as disclosed in European Patent 1168069A1 and Japanese Patent Application Laid-Open No. 2002-23303. In the case of the core Z shell structure, all or part of either the core part or the shell part is made of an organic silver salt other than silver aliphatic carboxylate, for example, an organic compound such as phthalic acid or benzimidazole. Silver salt may be used as a constituent of the crystal grains.

[0049] In the present invention, the tabular aliphatic carboxylic acid silver salt particles may be preliminarily dispersed together with a binder, a surfactant or the like, if necessary, and then dispersed and pulverized with a media disperser or a high-pressure homogenizer. preferable. As the preliminary dispersion method, for example, a general stirrer such as an anchor type or a propeller type, a high-speed rotating centrifugal radiation type stirrer (dissolver), or a high-speed rotating shear type stirrer (homomixer) can be used.

[0050] Further, as the media disperser, for example, a rolling mill such as a ball mill, a planetary ball mill, and a vibration ball mill, a bead mill that is a medium agitation mill, an attritor, and other basket mills can be used. Various types of high-pressure homogenizers can be used, such as a type that collides with walls, plugs, etc., a type that divides the liquid into multiple parts that collide with each other at high speed, and a type that passes a thin orifice.

[0051] Ceramics used for the ceramic beads used when dispersing the media include yttrium-stabilized zircoure and zircoua reinforced alumina (these are because of the low generation of impurities due to friction with the beads and the disperser during dispersion). A ceramic containing zircoure is hereinafter preferably abbreviated as zircoyu).

[0052] In the apparatus used for dispersing the tabular aliphatic carboxylic acid silver salt particles according to the present invention, as a material of the member in contact with the aliphatic carboxylic acid silver salt particles, for example, zirconium, alumina, nitriding Ceramics such as silicon and boron nitride or diamond Among them, it is preferable to use zircoyu. When the above dispersion is performed, it is preferable to add a binder concentration of 0.1 to 10% of the weight of the aliphatic carboxylic acid silver. It is preferable that the liquid temperature does not exceed 45 ° C throughout the dispersion. Further, as preferable operating conditions for this dispersion, for example, when a high-pressure homogenizer is used as the dispersing means, 29 to: LOOMPa, the number of operations is preferably 2 times or more. In the case where a media disperser is used as a dispersing means, the peripheral speed is preferably 6 to 13 mZ seconds.

[0053] In the present invention, it is preferable that the non-photosensitive aliphatic carboxylic acid silver salt particles are formed in the presence of a compound that functions as a crystal growth inhibitor or a dispersant. In addition, the compound that functions as a crystal growth inhibitor or dispersant is preferably an organic compound having a hydroxyl group or a carboxyl group.

In the present invention, the compound functioning as a dispersant and not a crystal growth inhibitor for aliphatic silver carboxylate particles coexists with the compound in the production process of aliphatic silver carboxylate particles. When an aliphatic silver carboxylate is produced under the conditions, a compound having a function and an effect of monodispersing with a smaller particle size than that produced under the conditions is described. Specific examples include monohydric alcohols having 10 or less carbon atoms, preferably secondary alcohols, tertiary alcohols, glycols such as ethylene glycol and propylene glycol, polyethers such as polyethylene glycol, and glycerin. The preferred amount of added calories is 10 to 200% by mass with respect to the silver aliphatic carboxylate.

[0055] On the other hand, branched fat containing isomers such as isoheptanoic acid, isodecanoic acid, isotridecanoic acid, isomyristic acid, isopalmitic acid, isostearic acid, isoarachidic acid, isobehenic acid, isohexaconic acid, etc. Group carboxylic acids are also preferred. In this case, preferred side chains include an alkyl group or a alkenyl group having 4 or less carbon atoms. In addition, aliphatic unsaturated carboxylic acids such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid, moloctic acid, eicosenoic acid, arachidonic acid, eicosapentaenoic acid, enolekaic acid, docosapentaenoic acid-docosahexaenoic acid, and ceracolonic acid Examples include acids. A preferable addition amount is 0.5 to: LOmol% of silver aliphatic carbonate.

[0056] Glycosides such as dalcoside, galactoside, fructoside, trehalose, sucrose, etc. Trehalose-type disaccharides, polysaccharides such as glycogen, dextrin, dextran, alginic acid, cellosolves such as methyl ceguchi sorb, ethyl ceguchi sorb, water-soluble organic solvents such as sorbitan, sorbit, ethyl acetate, methyl acetate, dimethylformamide, polyvinyl alcohol, Also preferred are water-soluble polymers such as polyacrylic acid, acrylic acid copolymer, maleic acid copolymer, carboxymethylenosenorose, hydroxypropenoresenorerose, hydroxypropinoremethenoresenorelose, polybylpyrrolidone, and gelatin. Listed as a compound. A preferable addition amount is 0.1 to 20% by mass with respect to the silver aliphatic carboxylate.

[0057] Alcohols having 10 or less carbon atoms, preferably secondary alcohols such as isopropyl alcohol, and tertiary alcohols such as t-butyl alcohol increase the solubility of the aliphatic carboxylic acid alkali metal salt in the particle production process. By reducing the viscosity, the dispersion is monodispersed and has a small particle size by increasing the stirring efficiency. Branched aliphatic carboxylic acids and aliphatic unsaturated carboxylic acids have higher steric hindrance than the straight chain aliphatic carboxylic acid silver, which is the main component, when the aliphatic carboxylic acid silver is crystallized, and the disorder of the crystal lattice is larger. As a result, large crystals are not formed, resulting in a small particle size.

[0058] (Reducing agent)

In the present invention, it is preferable to use the compound represented by the general formula (1) alone or in combination with another reducing agent having a different chemical structure as a silver ion reducing agent. The reducing agent used here is preferably a bisphenol type reducing agent. Examples of reducing agents that can be used in combination with the compound represented by the general formula (1) include paragraph numbers “0043” to “0045” of JP-A-11-65021, page 7 line 34 to page 18 of European Patent Publication (EP0803764A1). 1 line 2, paragraph numbers “0124” to “0133” of JP-A-2003-302723, paragraph numbers “0124” to “0127” of JP-A-2003-31595 4, paragraph number “0042” of JP-A-2004-4650 ”To“ 0 057 ”. The compound represented by the general formula (1) is preferably contained in an image forming layer containing an organic acid silver salt, but may be contained in an adjacent non-image forming layer!

[0059] In the general formula (1), R represents a hydrogen atom or a substituent. As a substituent,

1

Alkyl group, cycloalkyl group, alkenyl group, alkyl group, aryl group, heterocyclic group, Group, a rogen atom, a cyan group and the like. A hydrogen atom, an alkyl group, a cycloalkyl group, or a alkenyl group is preferable, and a hydrogen atom or an alkyl group is more preferable. These substituents may further have a substituent. Examples of the substituent include an alkyl group, a cycloalkyl group, a halogenated alkyl group, an alkyl group, an alkyl group, an aryl group, and a heterocyclic group. A halogen atom, a cyano group, a hydroxyl group, a carboxyl group, an alkoxy group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a rubamoyloxy group, an alkoxycarboxoxy group, an aryloxycarboxoxy group, Amino group, amino group, acylamino group, aminocarbolumino group, alkoxycarbolumino group, aryloxycarbolumino group, sulfamoylamino group, alkyl and arylsulfo-lumino group, mercapto group, alkylthio Group, arylthio group, heterocyclic group, sulfamoyl group, sulfo group, alkyl group And aryl sulfier groups, alkyl and aryl sulfonyl groups, acyl groups, aryl carbonyl groups, alkoxycarbonyl groups, strong rubamoyl groups, aryl and heterocyclic azo groups, imide groups, silyl groups, Examples thereof include hydrazino group, ureido group, boronic acid group, phosphato group, sulfato group, and other known substituents.

R2 and R3 each represent a branched alkyl group having 3 to 8 carbon atoms. Examples of branched alkyl groups include t-butyl, t-amyl, i-propyl, i-butyl, i-propyl, 1,1-dimethylbutyl, 1-methylcyclopentyl, 1-methylcyclobutyl, Examples include 1-methylcyclopropyl group, 1methylbutyl group, 1,3 dimethylbutyl group, 1-methylpropyl group, 1,1,2-trimethylpropyl group, 1-ethyl-1-methylpropyl group, and the like. A t-butyl group, a 1,1-dimethylbutyl group or a tamyl group is preferable, and a tamyl group is more preferable. These branched alkyl groups may further have a substituent, and examples of the substituent include a hydroxyl group, a cyano group, a mercapto group, a halogen atom, an amino group, an imide group, a silyl group, and a hydrazino group.

A and A are each a hydroxyl group or deprotected to form a hydroxyl group.

1 2

Represents a group to be obtained, preferably a hydroxyl group. Examples of the group that can be deprotected to form a hydroxyl group include groups that can be deprotected by the action of acid and Z or heat to form a hydroxyl group. Specifically, ether groups (methoxy, t-butoxy, aryloxy, benzyl Oxy, triphenyl methoxy, trimethylsilyloxy, etc.), hemiacetal group (tetrahydroloxy, etc.), ester group (acetyloxy, benzoyloxy, p-trobenzoyloxy, formyloxy, trifluoroacetyloxy, bivaluloyloxy, etc.), carbonate Groups (such as ethoxycarbonyloxy, phenoxycarbonyloxy, t-butyloxycarboxyloxy, etc.), sulfonate groups (such as p-toluenesulfo-loxy, benzensulfo-loxy, etc.), strong rubamoyloxy groups (such as phenylcarbamoyloxy) Thiocarboxoxy group (benzylthiocarboxoxy etc.), nitrate ester group, sulphateate group (2,4 dinitrobenzene sulphooxy etc.). n and m are each a force representing an integer of 3 to 5, preferably 3 or 4, and more preferably 3.

[0061] The structure of the substituents R, R, R, A and A exemplified above is a bisphenol type reducing agent.

1 2 3 1 2

This is one of the factors that determine the thermal properties and crystallinity of the photothermographic material. The melting point, thermal decomposition temperature, and crystallinity of the reducing agent in the photothermographic material greatly correlate with photographic performance.

[0062] When used in the photothermographic material according to the invention, the melting point is preferably 80 to 250 ° C and the thermal decomposition temperature is preferably 200 ° C or higher. Thermal development in which a reducing agent remains in the photosensitive material after development processing For photosensitive materials, the reducing agent with higher crystallinity suppresses material diffusion during storage, so the concentration of the capri portion due to the reduction reaction during image storage Since the fluctuation is small, the crystallinity of the reducing agent is high, which is better.

[0063] Specific examples of the reducing agent represented by the general formula (1) are shown below, but the present invention is not limited thereto.

[0064] [Chemical 2]

[ε ^] [S900]

LY

[0066] [Chemical 4] [S ^] 900]

[9 ^] [8900]

[6900]

OAV

§ Emperor 0 [6 ^] [ΐΖΟΟ]

[0072] [Chemical 10] [π¾] [ε οο]

[0074] [Chemical 12]

[0075] [Chemical 13]

[0076] The reducing agent may be contained in the coating solution by any method such as a solution form, an emulsified dispersion form, or a solid fine particle dispersion form, and may be contained in the photothermographic material.

In the present invention, US Pat. Nos. 3,589,903 and 4,021,249, British Patent 1,486,148 and JP-A-51-51933, 50-36110, Polyphenolic compounds described in 50- 116023, 5 2-84727 or JP-B 51-35727, such as 2, 2'-dihydroxy-1, / binaphthinole, 6, 6'-jib mouth Mo 2, 2 '— Dihydroxy 1, 1' Binaphthyl described in US Pat. No. 3,672,904 such as binaphthyl Tolls, and further described in, for example, US Pat. No. 3,801,321 such as 4-benzenesulfonamidophenol, 2-benzenesulfonamidophenol, 2,6-dichloro-4benzenesulfonamidophenol, 4-benzensulfonamidonaphthol, etc. Such sulfonamide phenols or sulfonamide naphthols can also be used as a silver ion reducing agent.

[0078] The amount of reducing agent used varies depending on the type of aliphatic carboxylic acid silver salt, reducing agent, and other additives. L0 mol, preferably 0.1 to 3 mol is suitable. In the present invention, a reducing agent is added to and mixed with a photosensitive emulsion solution composed of light-sensitive silver halide and aliphatic carboxylic acid silver salt grains and a solvent immediately before coating. Small and preferred.

[0079] (Photosensitive silver halide)

Photosensitive silver halide (also referred to as “halogen-silver”) is intrinsically light-absorbing as a characteristic of halogen-silver crystals, or artificially physicochemically radiates visible to infrared light. When absorbing light in any region within the light wavelength range from the ultraviolet light region to the infrared light region, it can absorb, and there is a physical / physical change in the silver halide crystal and in the Z or crystal surface. It refers to halogen-molybdenum crystal grains that have been processed and produced as possible.

[0080] The halogenated silver of the present invention can be prepared as a halogenated silver grain emulsion (also called a halogenated silver emulsion) using a known method. That is, any of acid method, neutral method, ammonia method, etc. can be used. As a method of reacting a soluble silver salt and a soluble halogen salt, any one of a one-side mixing method, a simultaneous mixing method, a combination thereof and the like can be used. Of these methods, the so-called controlled double jet method is preferred, in which halogen silver halide grains are prepared while controlling the formation conditions.

[0081] Usually, a silver halide silver seed grain is divided into two stages: grain nucleation and grain growth, and these can be performed continuously at once. Nuclei (seed grain) formation and grain growth are also possible. Alternatively, the method may be performed separately. The controlled double jet method, which controls the particle formation conditions such as pAg and pH, is preferable because the particle shape and size can be controlled. For example, when performing a method in which nucleation and grain growth are performed separately, first, a silver salt Aqueous solution and halide solution are uniformly and rapidly mixed in gelatin solution, and after nucleation (nucleation process), particles are grown while supplying silver salt solution and halide solution under controlled pAg, pH, etc. Halogenated silver particles are prepared by a grain growth process. After the formation of grains, the desired salt halide emulsion can be obtained by removing unnecessary salts, etc. by a known desalting method such as noodle method, fluorination method, ultrafiltration method, electrodialysis method, etc. Obtainable.

[0082] The particle size distribution of the halogen silver halide grains according to the present invention is preferably monodisperse. The monodispersion here means that the coefficient of variation of the particle diameter obtained by the following formula is 30% or less. Preferably it is 20% or less, More preferably, it is 15% or less.

[0083] Coefficient of variation of particle size (%) = (standard deviation of particle size Z average value of particle size) X 100

Examples of the shape of silver halide grains include cubes, octahedrons, tetrahedral grains, tabular grains, spherical grains, rod-shaped grains, and potato grains. Among these, cubic, octahedral grains, etc. A tetradecahedral, tabular halogen silver halide grain is preferred.

[0084] When tabular silver halide grains are used, the average aspect ratio is preferably 1.5 to 100, more preferably 2 to 50. These are described in U.S. Pat. Nos. 5,264,337, 5,314,798, and 5,320,958 to easily obtain the desired tabular grains. Can do. Further, grains having rounded corners of silver halide grains can be preferably used.

[0085] Although there is no particular limitation on the crystal habit of the outer surface of the silver halide grain, the crystal habit (plane) is selected according to the adsorption reaction of the sensitizing dye on the surface of the halogenated silver grain. In the case of using a sensitizing dye having a property, it is preferable to use silver halide grains having a relatively high ratio of crystal habits adapted to the selectivity. For example, when using a sensitizing dye that selectively adsorbs on the crystal face of the Miller index [100], it is preferable that the ratio of the [100] face is high on the outer surface of the silver halide grain. It is preferably 50% or more, more preferably 70% or more, and particularly preferably 80% or more. The ratio of the Miller index [100] plane is based on the adsorption dependency of the [111] plane and the [100] plane in the adsorption of the sensitizing dye. T. Tani, J. ImagingSci., 29, 165 (1985). [0086] The silver halide grains used in the present invention are preferably prepared using a low molecular weight gelatin having an average molecular weight of 50,000 or less at the time of forming the grains, but particularly used at the time of nucleation of the silver halide silver grains. Is preferred. The low molecular weight gelatin preferably has an average molecular weight of 50,000 or less, more preferably 2,000 to 40,000, and particularly preferably 5,000 to 25,000. The average molecular weight of gelatin can be measured by gel filtration chromatography. Low molecular weight gelatin can be hydrolyzed by adding gelatin-degrading enzyme to a commonly used gelatin aqueous solution with an average molecular weight of about 100,000, heating by adding acid or alkali, and heating at atmospheric pressure or under pressure. Can be obtained by thermal decomposition, decomposition by ultrasonic irradiation, or a combination of these methods. The concentration of the dispersion medium at the time of nucleation of the silver halide grains is preferably 5% by mass or less, more preferably 0.05 to 3.0% by mass.

[0087] The halogen silver halide grains used in the present invention preferably use a compound represented by the following general formula at the time of grain formation.

[0088] YO (CH CH O) (CH (CH) CH O) (CH CH O) Y

2 2 m 3 2 p 2 2 η

In the formula, Υ represents a hydrogen atom, SO M, or CO—B—COOM, and M represents a hydrogen atom.

Three

Represents an ammonium group substituted with an alkali metal atom, an ammonium group or an alkyl group having 5 or less carbon atoms, and B represents a chain or cyclic group forming an organic dibasic acid. m and n each represents 0 to 50, and p represents 1 to 100.

[0089] The polyethylene oxide compound represented by the above general formula is a process for producing a gelatin aqueous solution in the production of a normal silver halide photographic light-sensitive material, a water-soluble halide and a water-soluble compound in the gelatin solution. It has been used preferably as an antifoaming agent for significant foaming when the emulsion raw materials are stirred or moved, such as the step of adding a functional silver salt and the step of coating an emulsion on a support. A technique used as a foaming agent is described in, for example, JP-A-44 9497. The polyethylene oxide compound also functions as an antifoaming agent during nucleation. The compound represented by the above general formula is preferably used in an amount of 1% by mass or less based on silver, more preferably 0.01 to 0.1% by mass.

[0090] The polyethylene oxide compound is preferably added in advance to the dispersion medium before nucleation as long as it exists at the time of nucleation, but it may be added during nucleation. , During nucleation The silver salt aqueous solution to be used may be added to the ride aqueous solution. Preferably, it is used by adding 0.01 to 2.0% by mass to the aqueous solution of Rhino, Ride or both. In addition, the compound is preferably present for a time of at least 50% of the nucleation step, more preferably 70% or more. The polyethylene oxide compound may be added as a powder, or may be added in a solvent such as methanol.

[0091] The temperature at the time of nucleation is usually 5 to 60 ° C, preferably 15 to 50 ° C. Even if the temperature is constant, the temperature rise pattern (the temperature at the start of nucleation is Even when the temperature is increased gradually during nucleation at 25 ° C and the temperature at the end of nucleation is 40 ° C) or vice versa, it is preferable to control within the above temperature range. .

[0092] The concentration of the silver salt aqueous solution and halide aqueous solution used for nucleation is preferably 3.5 mol ZL or less, and more preferably 0.01 to 2.5 mol ZL. The rate of addition of silver ion during nucleation, the reaction solution 1L per ^{1. 5 X 10- 3 ~3. 0} X 10- 1 mol Z worth good better tool further preferably 3. 0 X 10- ³ ~8. is 0 X 10- ² mole Z min.

[0093] The pH at the time of nucleation is usually a force that can be set in the range of 1.7 to 10. The pH on the alkali side broadens the particle size distribution of the nuclei to be formed, and is preferably pH 2 to 6. Moreover, pBr at the time of nucleation is usually 0.05 to 3.0, preferably 1.0 to 2.5, more preferably 1.5 to 2.0.

[0094] The average grain size of the silver halide grains is usually 10 to 50 nm, preferably 10 to 40 nm, and more preferably 10 to 35 nm. If the average grain size of the silver halide grains is smaller than lOnm, the image density will decrease, or the light-irradiated image will be stored (the image obtained by thermal development will be used for diagnosis in a bright room, or stored in a bright room) The storage stability) may deteriorate. If it exceeds 50 nm, the image density may be lowered.

[0095] The average particle size referred to here means that the halogen-silver particles contained in the halogen-silver particle emulsion are cubic or octahedral so-called normal crystals. Say the length of the ridge. In addition, when the silver halide grains are tabular grains, it means the diameter when converted into a circular image having the same area as the projected area of the main surface. In addition, when it is not a normal crystal, for example, in the case of a spherical particle, a rod-like particle, etc., the diameter when considering a sphere equivalent to the volume of the halogenated silver particle is calculated as the particle size. Measurement is performed using an electron micrograph, The average particle size was determined by averaging the measured values of the particle size of 300 particles.

[0096] Further, in the present invention, the gradation of image density can be adjusted by using silver halide grains having an average particle diameter of 55 to 100 nm and halogenated silver grains having an average particle diameter of 10 to 50 nm in combination. In addition to the adjustment, the image density can be improved, and the decrease in image density over time can be improved (smaller). The ratio (mass ratio) of the silver halide grains having an average particle diameter of 10 to 50 nm and the silver halide grains having an average particle diameter of 55 to 100 nm is preferably 95: 5 to 50:50, more preferably 90: 10-60: 40.

[0097] As described above, when two types of silver halide emulsions having an average particle diameter are used, the two types of silver halide emulsions may be mixed and contained in the photosensitive layer. . In addition, it is also preferable that the photosensitive layer is composed of two or more layers for gradation adjustment and the like, and each layer contains the silver halide emulsions having the two average grain sizes separately. .

[0098] (silver halide grains having a silver iodide content of 5 to 100 mol%)

As the silver halide grains, silver halide grains containing silver iodide can be preferably used. As the halogen composition, the silver iodide content is preferably 5 to: LOO mol%. More preferably 40 to: LOO mol ^_0/0, more preferably 70: A LOO mol ^_0/0, preferably especially 90: a LOO mol%. If the silver iodide content is in this range, the intra-grain halogen composition distribution may be uniform, may be changed stepwise, or may be changed continuously. Further, halogen silver halide grains having a core Z shell structure having a high silver iodide content in the interior and Z or on the surface can also be preferably used. The preferred structure is a double to five-fold structure, more preferably a two to four-fold core Z seal particle.

[0099] As a method for introducing silver iodide into silver halide grains, a method of adding an aqueous alkali iodide solution during grain formation, fine grain silver iodide, fine grain silver iodobromide, fine grain silver iodochloride, fine grain iodine, A method of adding at least one fine particle among silver chlorobromide and a method using an iodide ion releasing agent described in JP-A-5-323487 and JP-A-6-11780 are preferred.

[0100] The silver halide grains according to the present invention preferably exhibit direct transition absorption derived from a silver iodide crystal structure at a wavelength of 350 to 440 nm. Whether these silver halides have light absorption of direct transition can be easily distinguished by the fact that exciton absorption due to direct transition is observed in the vicinity of 400 to 430 nm. [0101] (Heat conversion internal latent image type silver halide grains)

The photosensitive silver halide silver particle according to the present invention is a heat conversion internal latent image type (internal latent image type after heat development) halogen silver halide particle disclosed in JP-A-2003-270755 and JP-A-2005-106927, that is, The silver halide grains are preferably silver halide grains whose surface sensitivity is lowered by conversion from the surface latent image type to the internal latent image type by heat development. In other words, in the exposure before thermal development, a latent image that can function as a catalyst for a development reaction (reduction reaction of silver ions by a silver ion reducing agent) is formed on the surface of the halogen silver halide grains, and after the thermal development process has elapsed. In this exposure, a larger number of latent images are formed in the interior of the silver halide grains than the surface of the silver halide grains. It is preferable in terms of storage stability.

[0102] The heat-converted internal latent image type silver halide grains, like ordinary surface latent image type silver halide grains, are 0.00 per mol of an aliphatic carboxylic acid silver salt that can function as a silver ion source. It is preferably used in the range of 1 to 0.7 mol, preferably 0.03 to 0.5 mol.

[0103] (Amphiphilic dispersion of silver halide grains)

In the process of manufacturing a photothermographic material, from the viewpoint of improving photographic performance and color tone, the aggregation of silver halide grains is prevented, the silver halide grains are dispersed relatively uniformly, and finally the developed silver is dispersed. It is preferable that the desired shape can be controlled.

[0104] In order to prevent aggregation and uniformly disperse the gelatin used, the hydrophilic groups such as amino and carboxyl groups of gelatin are chemically modified according to the conditions of use, etc., to improve the properties of gelatin. Those modified are preferred. For example, the hydrophobization modification of the amino group in the gelatin molecule includes forces such as phenylcarbamoylation, phthalation, hatching, acetylation, benzoylation, ditrophylation, etc. is not. Further, the substitution rate is preferably 95% or more, more preferably 99% or more. Further, methyl esterification or amidation, which may be combined with a hydrophobic modification of a carboxyl group, may be mentioned, but it is not particularly limited thereto. The substitution rate of the carboxyl group is preferably 50 to 90%, more preferably 70 to 90%. Here, the hydrophobic group in the above-mentioned hydrophobization modification refers to a group whose hydrophobicity is increased by substituting the amino group and / or carboxyl group of gelatin. [0105] Further, it is also preferable depending on the purpose that the halogen silver halide emulsion is prepared by using a polymer that dissolves in both water and an organic solvent as described below, instead of gelatin or in combination with gelatin. For example, it is particularly preferred when the silver halide silver halide emulsion is uniformly dispersed in an organic solvent system. Examples of the organic solvent include alcohol-based, ester-based, and ketone-based compounds. In particular, ketone organic solvents such as methanol, acetone, methyl ethyl ketone, and jetyl ketone are preferable.

[0106] The polymer that is soluble in both water and the organic solvent may be any of natural polymers, synthetic polymers, and copolymers. For example, gelatins, rubbers and the like modified so as to belong to the category of the present invention can be used. Alternatively, polymers belonging to the following classifications can be used by introducing functional groups suitable for the purpose of preventing aggregation and uniform dispersion.

[0107] Examples of the polymer include polybulu alcohols, hydroxyethyl celluloses, cellulose acetates, cellulose acetate butyrates, polybutylpyrrolidones, casein, starch, polyacrylic acid and acrylic esters, polymethyl Methacrylic acid and methacrylic acid esters, polyvinyl chlorides, polymethacrylic acids, styrene-maleic anhydride copolymers, styrene-acrylonitrile copolymers, styrene-butadiene copolymers, polybulucetals ( Polybulformal and Polybutyral), polyesters, polyurethanes, phenoxy resins, polysalts and vinylidenes, polyepoxides, polycarbonates, polyvinyl acetates, polyolefins, cellulose esters, polyamides And the like. Several kinds of these polymers may be copolymers, but particularly preferred are polymers obtained by copolymerizing monomers of acrylic acid, methacrylic acid and esters thereof.

[0108] The polymer may be a polymer that dissolves in both water and an organic solvent in the same state, but may be dissolved in water or an organic solvent by pH control or temperature control, or may be insoluble. included. For example, a polymer having an acidic group such as a carboxyl group becomes hydrophilic in a dissociated state depending on the type, but becomes lipophilic when it is lowered to a non-dissociated state and can be made soluble in a solvent. Conversely, polymers having amino groups become lipophilic when the pH is raised, and become ionic and water-soluble when the pH is lowered. The cloud point phenomenon is well known for non-active agents. However, it becomes lipophilic and soluble in organic solvents when the temperature rises, and it becomes hydrophilic (that is, soluble in water) when the temperature is lowered (as a well-known thermosensitive polymer, Poly-N-i-propylacrylamide and copolymers thereof) are also included in the present invention. If micelles can be formed and evenly emulsified even if not completely dissolved.

[0109] In the present invention, since various monomers are combined, it is not generally stated which monomer should be used to what extent, but a hydrophilic monomer and a hydrophobic monomer are used in an appropriate ratio. It can be easily understood that the desired polymer can be obtained by combining them.

[0110] The polymer that dissolves in both the water and the organic solvent may be adjusted by dissolving the pH and the like as described above, or may be unadjusted, but at least 1% by mass or more (25 ° C with respect to water). C) and an organic solvent having a solubility of 5% by mass or more (25 ° C.) in methyl ethyl ketone is preferred. From the viewpoint of solubility, so-called block polymers, graft polymers, comb polymers, and the like are more suitable as polymers that are soluble in both water and organic solvents used in the present invention. Comb polymers are particularly preferred. The isoelectric point of the polymer is preferably pH 6 or less.

[0111] In order to produce a comb polymer, various methods can be used, but it is desirable to use a monomer capable of introducing a side chain having a molecular weight of 200 or more into the comb part (side chain). In particular, it is preferable to use an ethylenically unsaturated monomer containing a polyoxyalkylene group such as ethylene oxide or propylene oxide. As the polyoxyalkylene group-containing ethylenically unsaturated monomer, those having a polyoxyalkylene group represented by the following general formula are particularly preferable.

[0112] One (EO) — (PO)-(TO) One R

k m n

In the formula, E represents an ethylene group, P represents a propylene group, T represents a butylene group, and R represents a substituent. Examples of the butylene group include tetramethylene and i-butylene groups. k represents an integer of 1 to 300, m represents an integer of 0 to 60, and ηί. Preferably, ίMA ki ma 1 ~ 200, mi ma 0 ~ 30, ηί ma 0 ~ 20. However, k + m + n≥2 is preferable in order to be a comb polymer. The polyoxyalkylene group-containing ethylenically unsaturated monomer may be used alone or in combination of two or more. [0113] The substituent represented by R represents an alkyl group, an aryl group, a heterocyclic group, and the like, and examples of the alkyl group include methyl, ethyl, propyl, butyl, hexyl, octyl, dodecyl and the like. Examples of aryl groups include phenyl and naphthyl groups, and examples of heterocyclic groups include enyl and pyridyl groups. These groups further include halogen atoms, alkoxy groups (methoxy, ethoxy, butoxy, etc.), alkylthio groups (methylthio, butylthio, etc.), acyl groups (acetyl, benzoyl, etc.), alkanamide groups (acetoamide, propionamide, etc.) ), An arylamide group (such as benzoylamide) or the like. Further, these substituent groups may be further substituted by these groups.

[0114] The polyoxyalkylene group represented by the general formula can be introduced into the polymer by using an ethylenically unsaturated monomer having the polyoxyalkylene group. Examples of the ethylenically unsaturated monomer having these groups include polyoxyalkylene acrylate (and meta acrylate), which are commercially available hydroxypoly (oxyalkylene) materials such as trade name " Pull mouth-g '[Pluronic (Asahi Denki Kogyo Co., Ltd.)], Ade force polyether (Asahi Denka Kogyo Co., Ltd.), Carbowax [Carbowax (Glico-Products Co., Ltd.)], Triton [Roriton And PE G (Daiichi Kogyo Seiyaku Co., Ltd.) and the like can be produced by reacting them with acrylic acid, methacrylic acid, acrylic chloride, methacrylic chloride or acrylic acid anhydride by a known method. In addition, poly (oxyalkylene) diathalylate produced by a known method can also be used.

[0115] In addition, commercially available monomers include, as a hydroxyl group-terminated polyalkylene glycol mono (meth) ate acrylate manufactured by NOF Corporation, Blemmer PE-90, Blemmer PE-200, Blemmer PE-350, Blemmer AE-90. , Blemmer AE—200, Blemmer AE 400, Blemmer PP—1000, Blemmer PP—500, Blemmer PP—800, Blemmer AP—150, Blemmer AP—400, Blemmer AP—550, Blemmer AP—800, Blemmer 50PEP— 300, Blemmer 70PEP-350B, Blemmer AEP series, Blemmer 55PET-400, Blemmer 30PET-800, Blemmer 55PET-80, Blemmer AET series, Blemmer 30PPT-800, Blemmer 50ΡΡΤ-800, Blemmer 70ΡΡΤ-800, Blemmer APT series , Blemmer 10PPB-500B, Blemmer 10APB-500B and the like. Similarly, Nippon Oil & Fats Alkyl Powder As end polyalkylene glycol mono (meth) acrylates, Blemmer PME—100, Blemmer PME—200, Blemmer PME—400, Blemmer PME—1000, Blemmer One PME—4000, Blemmer AME—400, Blemmer 50POEP—800B, Blemma 50AOEP—800B, Blemmer PLE—200, Blemmer ALE—200, Blemmer ALE—800, Blemmer PSE—400, Blemmer PSE—1300, Blemmer ASEP series, Blemmer PKEP series, Blemmer AKEP series, Blemmer ANE 300, Blemmer ANE—1300 , BLEMMER PNEP series, BLEMMER PNPE series, BLEMMER 43ANEP-500, BLEMMER 70ANEP-550, etc .; Kyoeisha Co., Ltd. LIGHT ESTER MC, LIGHT ESTER 130MA, LIGHT ESTER 041MA, LIGHT ATALYLATE BO-A, LIGHT ATTALRATE EC— A, light attalate MTG A, Light Atari les over preparative 130A, light Atari rate dpm A, Light Atari rate P- 200A, light Atari rate NP- 4EA, Light Atari rate NP- 8EA and the like.

[0116] As the polymer, a graft polymer using a so-called macromer can also be used.

For example, it is described in “New Polymer Experiments 2, Polymer Synthesis, Reaction” edited by Polymer Society of Japan, Kyoritsu Shuppansha, 1995. It is also described in detail in Yuya Yamashita's “Chemical Monomer Chemistry and Industry” published by IPC, 1989. Among the macromers, the useful molecular weight is in the range of 10,000 to 100,000, the preferred range is 10,000 to 50,000, and the particularly preferred range is in the range of 10,000 to 20,000. If the molecular weight is less than 10,000, the effect cannot be exerted, and if it exceeds 100,000, the polymerizability with the copolymerization monomer forming the main chain deteriorates. Specifically, Toagosei Co., Ltd. AA-6, AS-6S, AN-6S, etc. can be used.

Of course, the present invention is not limited to the above specific examples. The polyoxyalkylene group-containing ethylenically unsaturated monomer may be used alone or in combination of two or more.

[0118] Other monomers specifically reacted with the above monomers include (meth) acrylic acid esters, (meth) acrylamides, aryl esters, aryloxyethanols, buresters, bur esters. , Dialkyl itaconate, mono (or di) alkyl esters of fumaric acid, etc., crotonic acid, itaconic acid, (meth) acrylonitrile, maleylnitrile, styrene, etc. [0119] Specific examples include the following compounds.

[0120] Acrylic acid esters: methyl acrylate, ethyl acrylate, propyl acrylate, chloro ethino rare acrylate, 2-hydroxy ethino rare acrylate, trimethylol propane mono acrylate, benzyl acrylate, methoxy benzyl Atalylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, etc., methacrylic acid esters: methyl methacrylate, ethyl methacrylate, propyl methacrylate, chlorethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl methacrylate Trimethylolpropane monometatalylate, benzenoremetatalylate, methoxybenzyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, acrylamides: acrylamide, N-alkyl Acrylamide (Alkyl group having 1 to 3 carbon atoms, such as methyl, ethyl, propyl), N, N dialkylacrylamide, N hydroxyethyl-N-methylacrylamide, N-2-acetamidoethyl-N-acetylethylacrylamide Such. Further, as alkyloxyacrylamide, methoxymethylacrylamide, butoxymethylacrylamide, etc., methacrylamides: methacrylamide, N-alkylmethacrylamide, N-hydroxyethyl-N-methylmethacrylamide, N2-acetamidoethyl N-acetyl Merylamide, methoxymethyl methacrylamide, butoxymethyl methacrylamide, etc. allylic compounds: allylic esters (alaryl acetate, allylic acid proallyl, allylic caprylate, allylic laurate, allylic palmitate, allylic stearate, benzoic acid) Acid aryl, acetoacetyl acetate, lactyl lactate, etc.), aryloxetano mononole, etc., butyl ethers: alkyl butyl ether (hexyl vinyl ether, octino levinino leetenore, decino levinino) Leetenore, ethinorehexinorevininoreethenore, methoxetinorevininoreetenore, ethoxyethinorevininoatenore, chronoretinolinobine ether, 1 methyl 2, 2-dimethylpropyl vinyl ether, 2 ethino lebutinore vininore Tenole, hydroxyethinolevinoleateol, diethyleneglycolenovininate ether, dimethylaminoethyl vinyl ether, jetylaminoethyl vinyl ether, butinoleaminoethinolevinoleateolate, benzyl vinyl ether, tetrahydrofurfuryl bur ether, etc.) Bull esters: Bull butyrate, beluo i-butyrate, bull trimethyl acetate, vinyl jetyl acetate, belvalate, vinyl capate, bull chloracetate Over DOO, Bulle di chloroacetate, Bulle methoxy § cetearyl one , Butyl butoxyacetate, vinyl latate, bur-β-phenyl butyrate, bicyclohexyl carboxylate, etc., dialkyl itaconates: dimethyl itaconate, jetyl itaconate, dibutyl itaconate, etc. Dialkyl esters or monoalkyl esters of fumaric acid: dibutyl fumarate, etc., crotonic acid, itaconic acid, acrylonitrile, metatalonitrile, maleylnitrile, styrene, etc.

[0121] In the case of introducing a linear or branched alkyl group having 4 to 22 carbon atoms, an aromatic group, or a 5-membered or higher polycyclic group, among the above-mentioned monomers or other monomers, Choose monomers that contain these functional groups! For example, 1-Buylimidazole and its derivatives can be used to introduce a heterocyclic group having 5 or more members. Furthermore, an isocyanate group or an epoxy group is introduced into the polymer in advance, and these are combined with alcohols or amines containing a linear or branched alkyl group, an aromatic group, or a 5- or more-membered heterocyclic group. Various functional groups may be introduced into the polymer by reaction. To introduce isocyanate cyanoxy, a power lens ΜΟΙ (manufactured by Showa Denko KK) can be used as a blender G (manufactured by NOF Corporation). It is also preferable to introduce urethane bonds.

[0122] The following are specific examples of the amphiphilic polymer for preparing halogenated silver used in the present invention. The present invention is not limited to these.

[0123] [Chemical 14]

15]

(Polymerization initiator)

As the polymerization initiator, an azo polymer polymerization initiator or an organic peroxide can be used. As the azo polymer polymerization initiator, ABN-R (2, 2'-azobisisobuty-tolyl), ABN-V (2, 2'-azobis (2,4-dimethylvaleronitrile) manufactured by Nippon Hydrazine Kogyo Co., Ltd. )), ABN- Ε (2, 2 '-azobis (2-methyl petit-tolyl))). Organic Peroxides include benzoyl peroxide, dimethyl ethyl ketone peroxide, lauryl peroxide, Pertetra A, Perhexa HC, Perhexa TMH, Parhexa C, and Monohex, manufactured by NOF Corporation. NOxa V, NOHEXA 22, NONOHEXA MC, NOVu chinole Η, Λ—cumyl H, park mill P, permenta H, PEROCTA H, perbutyl C, perbutyl D, perhexyl D, perroyl IB, NO Nipple 355, Parroil, Parroil, Parroy Nole SA, Nyper BW, Nyper BMT—K40, Nyper ΒΜΤ— ナイ 40, Nipper , Parroyl OPP, Parroyl SBP, Park Mill ND, Bar Octa ND, Norcyclo ND, Perhexyl ND, Perbutyl ND, Perhexyl PV , Monohexa 25 0, Peroctor 0, Perhexyl 0, Perbutyl 0, Perbutyl IB, Perbutyl L, Novutinore 355, Perhexyl I, Perbutinole I, Perbutyl E, Nohexa 25Z, Perhexa 25MT Perbutyl A, perhexyl Z, perbutyl ZT, perbutyl soot and the like.

[0126] Examples of the polymerization inhibitor include hydroquinone and ρ-methoxyphenol, which are quinone-based inhibitors. Seiko Chemical's phenothiazine, methoquinone, non-flex arno, ΜΗ (methylhydroquinone), TBH (t-butylhydroquinone), PBQ (p-benzoquinone), tolquinone, TBQ (t-butyl-p-benzoquinone), 2,5-diphenyl p-benzoquinone Etc.

[0127] The isoelectric point of the polymer is preferably pH 6 or less. If a polymer with a high isoelectric point is used, as will be described later, when desalting of silver halide silver particles by the coagulation precipitation method, decomposition of the silver halide grains is promoted, and photographic performance is adversely affected. It is. In addition, when dispersing the silver or silver oxide fine particles in the solvent, it is necessary to disperse unless the pH is raised. The isoelectric point of the polymer is measured by, for example, isoelectric focusing or measuring the pH after passing a 1% aqueous solution through a mixed bed column of cation and cation exchange resin.

[0128] Various acidic groups can be introduced to lower the isoelectric point of the polymer. Examples include a carboxyl group and a sulfo group. In addition to using monomers of acrylic acid and methacrylic acid for introducing a carboxyl group, a polymer containing methyl methacrylate or the like can be obtained by partially hydrolyzing. For introduction of carboxyl group, styrene sulfo In addition to using 2-acrylamide-2-methylpropanesulfonic acid as a monomer, it can also be introduced after polymer preparation by various sulfuric acid methods. In particular, the use of a carboxylic acid is particularly preferable because the property can be changed to water-soluble by neutralization or semi-neutralization in which the solubility in a solvent is relatively high in an unneutralized state. Neutralization can be carried out with sodium or potassium salts, and organic salts such as ammonia, monoethanolamine, diethanolamine, triethanolamine and the like may be used. Imidazoles, triazoles and amidoamines can be used.

[0129] Polymerization is preferably carried out in the presence of a solvent from the viewpoint of workability that can be carried out in the presence or absence of a solvent. Preferred solvents include alcohols such as ethanol, i-propyl alcohol, butanol, i-butanol, and t-butanol, ketones such as acetone, methyl ethyl ketone, methyl-i-butyl ketone, and methyl amyl ketone, and acetic acid. Esters such as methyl, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and butyl lactate, methyl 2-oxypropionate, ethyl 2-oxypropionate, propyl 2-oxypropionate, 2-oxypropion Acid butyl, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, 2-methoxypropionate

Monocarboxylic acid esters such as butyl onate, polar solvents such as dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, ethers such as methyl solvosolve, cellosolve, butylcerosolve, butyl carbitol, ethylcetosolve sorb acetate, propylene Propylene glycols such as lenglycol, propylene glycolenomonomethylenole ether, propylene glycolenomonoethylenoate acetate, propylene glycolenomonoethylenoate acetate, propylene glycol monobutyl ether acetate, and esters thereof, 1, 1, 1 Halogen solvents such as trichloroethane and chloroform, ethers such as tetrahydrfuran and dioxane, aromatics such as benzene, toluene and xylene, and perfluoro Tan, fluorine I spoon Ina one Torikiddo such as perfluoro tributyl § Min, and the like.

[0130] Depending on the polymerizability of each monomer, a dropping polymerization method in which a monomer and an initiator are added dropwise to a reaction vessel is also effective for obtaining a polymer having a uniform composition. Column filtration, re- Unreacted monomer can be removed by removal by precipitation purification, solvent extraction or the like. Alternatively, low-boiling unreacted monomers can be removed by stripping.

[0131] (Chemical sensitization, spectral sensitization, supersensitization)

The photosensitive silver halide grains can be chemically sensitized. For example, by a method described in JP-A-2001-249428 and 2001-249426, a compound that releases chalcogens such as sulfur, selenium, and tellurium, and a noble metal compound that releases noble metal ions such as gold ions. Use to form a chemical sensitization center (chemical sensitization nucleus) capable of capturing electrons or holes generated by photoexcitation of photosensitive silver halide grains or spectral sensitizing dyes on the grains. it can. In particular, it is preferably chemically sensitized by an organic sensitizer containing a chalcogen atom.

[0132] The organic sensitizer containing a chalcogen atom is preferably a compound having a group capable of adsorbing to halogenated silver and an unstable chalcogen atom site. These organic sensitizers are disclosed in JP-A-60-150046, JP-A-4-109240, JP-A-11-218874, JP-A-11-218875, JP-A-11-218876, JP-A-11-194447, etc. Organic sensitizers having various structures can be used, and among them, at least one compound having a structure in which a chalcogen atom is bonded to a carbon atom or a phosphorus atom by a double bond It is preferable. In particular, a thiourea derivative having a heterocyclic group and a triphenylphosphine sulfide derivative are preferred. As a method for chemical sensitization, techniques according to various chemical sensitization techniques conventionally used in the production of silver halide light-sensitive materials for conventional wet processing can be used (TH James edition “The Theory of”). the Photograph ic Process "4th edition, Macmillan Publishing Co., Ltd. 1977, edited by the Japan Society of Photography," Basics of Photographic Engineering (Silver Salt Photography), Corona, 1979). When sensitized and then mixed with non-photosensitive aliphatic carboxylic acid silver salt particles, chemical sensitization can be performed by a conventional method.

[0133] The amount of chalcogen compound used as an organic sensitizer varies depending on the chalcogen compound used, silver halide grains, the reaction environment during chemical sensitization, etc. 10- ⁸ ~: L0- ² more preferably moles preferably fixture 10- ⁷ ~: L0- ³ molar is used.

[0134] There are no particular restrictions on the environmental conditions for chemical sensitization, but photosensitive halogen silver halide grains. Chalcogen atoms in the presence of compounds that can annihilate or reduce the size of their chalcogen silver or silver nuclei, and in particular in the presence of oxidizing agents that can oxidize silver nuclei. It may be preferable to perform chalcogen sensitization using an organic sensitizer containing benzene. The sensitizing conditions in this case are 6 to pAg: 7 to 10, more preferably 7 to 10, pH 5 to 8 is more preferably 4 to 10, and 30 to 30. It is preferable to apply sensitization at a temperature below ° C.

[0135] The optical sensitization using these organic sensitizers is preferably performed in the presence of a heteroatom-containing compound having adsorptivity to the spectral sensitizing dye or the halogen silver halide particles. By performing chemical sensitization in the presence of a compound having adsorptivity to the silver halide silver particles, dispersion of the chemically sensitized central core can be prevented, and high sensitivity and low capri can be achieved. Spectral sensitizing dyes will be described later, but nitrogen-containing heterocyclic compounds described in JP-A No. 3-24537 are preferred as heteroatom-containing compounds having adsorptivity to halogenated silver. As an example. In the nitrogen-containing heterocyclic compound, examples of the heterocyclic ring include pyrazole, pyrimidine, 1,2,4-triazole, 1,2,3-triazole, 1,3,4-thiadiazole, 1,2,3-thiadiazole, 1, 2, 4-thiadiazole, 1, 2, 5-thiadiazole, 1, 2, 3, 4-tetrazole, pyridazine, 1, 2, 3-thiadiazine ring, these ring forces ~ 3 bonded Examples of the ring include triazolotriazole, diazaindene, triazaindene, and pentazaindene rings. A heterocyclic ring condensed with a monocyclic heterocyclic ring and an aromatic ring, for example, phthalazine, benzimidazole, indazole, benzthiazole ring and the like can also be applied.

[0136] Among these, azaindene ring is preferable, and an azaindene compound having a hydroxyl group as a substituent, for example, hydroxytriazaindene, tetrahydroxyazaindene, hydroxypentazaindene compound and the like are more preferable. U ,.

[0137] The heterocyclic ring may have a substituent other than a hydroxyl group. Examples of the substituent include an alkyl group, a substituted alkyl group, an alkylthio group, an amino group, a hydroxyamino group, an alkylamino group, a dialkylamino group, an arylamino group, a carboxyl group, an alkoxy group, a carbonyl group, a halogen atom, and a cyano group. And so on.

[0138] The amount of the heterocyclic compound added depends on the size, composition, and other conditions of the halogenated silver particles. The amount of force approximate to Wataru connexion vary over a wide range depending on the matter or the like is in the range of 1 0 one ⁶ -1 mole per Harogeni匕銀1 mol, preferably 10 ⁴ to 1 ₀ - is ¹ mols .

[0139] The photosensitive silver halide can be subjected to noble metal sensitization by using a compound that releases noble metal ions such as gold ions. For example, chloroaurate and organic gold compounds can be used as gold sensitizers. The gold sensitization technique disclosed in JP-A-11-194447 is a reference.

[0140] In addition to the above-described sensitization methods, reduction sensitization methods and the like can also be used. As a shell-like compound for reduction sensitization, ascorbic acid, diacid thiourea, stannous chloride, A hydrazine derivative, a borane compound, a silane compound, a polyamine compound, or the like can be used. Further, reduction sensitization can be performed by ripening the emulsion while maintaining the pH at 7 or more or pAg at 8.3 or less.

[0141] In the present invention, the silver halide grains subjected to chemical sensitization were formed in the presence of an aliphatic carboxylic acid silver salt, but the aliphatic carboxylic acid silver salt was not present. It may be formed under conditions, or a mixture of both.

[0142] When the surface of the photosensitive silver halide grains is chemically sensitized, it is preferable that the chemical sensitization effect substantially disappears after the thermal development process. Here, the effect of chemical sensitization substantially disappears when the sensitivity of the imaging material obtained by the chemical sensitization technique is chemically sensitized after the thermal development process! / Sensitive, say that the sensitivity decreases to 1.1 times or less. In order to eliminate the chemical sensitization effect in the heat development process, an oxidant that can destroy the chemical sensitization center (chemical sensitization nucleus) by an acid-oxidation reaction at the time of heat development, for example, release of the above-mentioned halogen radicals. It is necessary to add an appropriate amount of the organic compound or the like to the emulsion layer or Z and the non-photosensitive layer of the imaging material. The content of the oxidant is preferably adjusted in consideration of the oxidizing power of the oxidant, the decrease in the chemical sensitization effect, and the like.

[0143] The photosensitive silver halide is preferably subjected to spectral sensitization by adsorbing a spectral sensitizing dye. As the spectral sensitizing dye, cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, styryl dyes, hemiyanine dyes, oxonol dyes, hemioxonol dyes, and the like can be used. For example, JP-A-63-159841, 60-140335, 63-231437, 63-259 651, 63-304242, 63-15245, U.S. Patents 4, 639, 414, 4, 7 40, 455, 4, 741, 966, 4, 751, 175, Sensitizing dyes described in US Pat. No. 4,835,096 can be used.

[0144] Useful sensitizing dyes used in the present invention include, for example, Research Disclosure (hereinafter abbreviated as RD) 17643IV—A (December 23, 1978), RD18431X (August 1978 4 page 37) ) Is described in the literature described or cited. In particular, the power of using sensitizing dyes with spectral sensitivity suitable for the spectral characteristics of various laser imagers and scanner light sources is preferred. For example, the compounds described in JP-A Nos. 934078, 954409, and 980679 are preferably used.

[0145] Useful cyanine dyes are cyanine dyes having basic nuclei such as thiazoline nucleus, oxazoline nucleus, pyrroline nucleus, pyridine nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus and imidazole nucleus. In addition to the basic nuclei described above, preferred merocyanine dyes are preferably thiohydantoin, rhodanine, oxazolidinedione, thiazolinedione, barbituric acid, thiazolinone, malono-tolyl and pyrazo. Includes acidic nuclei such as Ron nuclei.

[0146] In the present invention, a sensitizing dye having spectral sensitivity particularly in the infrared can also be used.

Examples of infrared spectral sensitizing dyes preferably used include infrared spectral sensitizing dyes disclosed in US Pat. Nos. 4,536,473, 4,515,888, and 4,959,294. It is

In the photothermographic material of the present invention, the sensitizing dye represented by the following general formula (SD1) and the following general formula (SD2) as described in JP-A-2004-309758 It is preferable that at least one sensitizing dye is selected and contained.

[0148] [Chemical 16] General formula (SD1)

[0149] In the formula, Y and Y are each an oxygen atom, a sulfur atom, a selenium atom, or a CH = CH group.

1 2

L to L each represent a methine group. R ¹ and R ² each represent an aliphatic group. R ³ and

1 9

R ⁴ each represents a lower alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, an aryl group or a heterocyclic group. W, W, W, and W are each a hydrogen atom, a substituent, or

1 2 3 4

A group of nonmetallic atoms necessary to form a condensed ring by bonding between W and W or W and W.

1 2 3 4

The Or R ³ and W, R ³ and W, R ⁴ and R ³ , R ⁴ and W

1 2 4

Represents a group of non-metallic atoms necessary to form. X

1 represents the ions necessary to cancel the charge in the molecule, and kl represents the number of ions required to cancel the charge in the molecule. ml represents 0 or 1; nl and n2 each represents 0, 1 or 2; However, nl and n2 are not 0 at the same time.

[0150] The above infrared sensitizing dyes are, for example, the authors of F'Nom's: The Chemistry of Heterociciic and ompounds, ^ ¾18 ^, The Cyanme Dyes and Related and o mpounds (A. Weissberger ed. Interscience Company dried (J, New York, 1964) [It can be easily synthesized by this method.

[0151] These infrared sensitizing dyes may be added at any time after the preparation of halogen silver, for example, added to a solvent or dispersed in the form of fine particles in a so-called solid dispersion state. It can be added to a light-sensitive emulsion containing grains or halogenated silver grains Z aliphatic carboxylic acid silver salt grains. Similarly to the compound containing a helium atom having an adsorptivity to the above-described halogen silver particles, it is added to the halogen silver particles prior to chemical sensitization and adsorbed. Then, chemical sensitization can be performed, which can prevent dispersion of the chemical sensitization central core and achieve high sensitivity and low capri.

[0152] The above-mentioned spectral sensitizing dye may be used alone, but as described above, it is preferable to use a combination of plural kinds of spectral sensitizing dyes. This combination is often used for the purpose of supersensitization and enlargement or adjustment of the photosensitive wavelength region.

[0153] Emulsions containing photosensitive silver halides and aliphatic carboxylic acid silver salts used in heat-developable photosensitive materials, together with sensitizing dyes, substantially do not have a spectral sensitizing action themselves or visible light. A substance that does not absorb and exhibits a supersensitizing effect may be included in the emulsion, so that the silver halide grains may be supersensitized!

[0154] Useful sensitizing dyes, combinations of dyes exhibiting supersensitization, and substances exhibiting supersensitization are described in RD17643 (issued in December 1978), page J, Section IV, or Japanese Patent Publication 9- No. 25500, No. 43-4933, JP-A-59-19032, JP-A-59-192242, JP-A-5-341432, and the like. Aromatic mercapto compounds or mercapto derivative compounds are preferred.

[0155] Ar-SM

In the formula, M is a hydrogen atom or an alkali metal atom, and Ar is an aromatic ring or condensed aromatic ring having one or more nitrogen, sulfur, oxygen, selenium, or tellurium atoms. The heteroaromatic ring is preferably benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotelrazole, imidazole, oxazole, pyrazole, triazole, triazine. , Pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline, or quinazoline. However, other heteroaromatic rings are also included.

[0156] Mercapto derivative compounds that substantially produce the above mercapto compounds when contained in a dispersion of an aliphatic carboxylic acid silver salt or a silver halide grain emulsion are also included. In particular, preferred examples include mercapto derivative compounds represented by the following.

[0157] Ar-S-S -Ar

In the formula, Ar has the same meaning as in the case of the mercaptoic compound represented above.

[0158] The above heteroaromatic ring includes, for example, a halogen atom (chlorine, bromine, iodine), a hydroxyl group, Amino group, carboxyl group, alkyl group (having 1 or more carbon atoms, preferably having 1 to 4 carbon atoms) and alkoxy group (1 or more carbon atoms, preferably 1 to 4 carbon atoms) It may have a substituent selected from the group consisting of those having atoms.

[0159] In addition to the supersensitizer described above, a macrocyclic compound having a heteroatom disclosed in JP-A-2001-330918 can also be used as the supersensitizer.

[0160] The supersensitizer is preferably used in a photosensitive layer containing an aliphatic carboxylic acid silver salt and a silver halide silver particle in an amount of 0.001 to 1.0 mol per mol of silver. Particularly preferred is 0.01 to 0.5 mole per silver mole.

[0161] In the present invention, spectral sensitization is performed by adsorbing a spectral sensitizing dye to the surface of photosensitive halogen silver halide grains, and the spectral sensitization effect is substantially reduced after the thermal development process. It is preferable to disappear. Here, the spectral sensitization effect substantially disappears when the sensitivity of the imaging material obtained with a sensitizing dye, supersensitizer, etc. is spectrally sensitized after the thermal development, 1. It means to decrease to less than 1 times.

[0162] In order to eliminate the spectral sensitization effect in the thermal development process, a spectral sensitizing dye that is easily detached from the halogenated silver particles by heat is used during thermal development, or Z and the spectral sensitizing dye are acidified. It is necessary to contain an appropriate amount of an oxidizing agent that can be destroyed by the reaction, such as the halogen radical-releasing compound, in the emulsion layer or Z and the non-photosensitive layer of the imaging material. The content of the oxidizing agent is preferably adjusted in consideration of the oxidizing power of the oxidizing agent, the reduction range of the spectral sensitization effect, and the like.

[0163] (Color tone adjusting agent)

Next, the color tone of an image obtained by thermally developing a photothermographic material will be described.

[0164] Regarding the color tone of an output image for medical diagnosis such as a conventional X-ray photographic film, it is said that a cold tone image tone is easier for a reader to obtain a more accurate diagnostic observation result. Here, the cool image tone means a pure black tone or a bluish black tone of a black image. On the other hand, a warm image tone is said to be a dark black tone with a black image, but in order to allow a more precise quantitative discussion, the International Lighting Commission (CIE) ), Based on the recommended expression.

[0165] The terms "more cold" and "more warm" in terms of color tone refer to the minimum density Dmin and optical density. It can be expressed by the hue angle hab at D = l. That is, the hue angle hab is calculated using the color coordinates a * and b * of the L * aV color space, which is a color space with a perceptually uniform rate recommended by the International Commission on Illumination (CIE) in 1976. It is calculated by the following formula.

[0166] (Formula) hab = tan—l (b * Za *)

As a result of examination by the expression method based on the hue angle, it is preferable that the hue of the photothermographic material of the present invention after development is in the range of hue angle hab of 180 degrees, hab, 270 degrees, and more preferably 200. It was found to be hab 270 degrees, most preferably 220 hab 260 degrees. This is disclosed in Japanese Patent Laid-Open No. 2002-6463.

[0167] Conventionally, u, V * or a *, b * in the CIE 1976 (L * u * v *) color space or (LW) color space near an optical density of 1.0 is a specific numerical value. It is known that a diagnostic image with a favorable visual color tone can be obtained by adjustment, and is described in, for example, Japanese Patent Application Laid-Open No. 2000-29164.

[0168] As a result of further intensive studies on photothermographic materials, the horizontal axis is u * or a * in the CIE 1976 (L uV *) color space or (L * aV) color space. When plotting u *, V or a *, b * at various photographic densities on a graph with the axis as V * or b *, and creating a linear regression line, the linear regression line is set to a specific range. By adjusting to, it was found that it has a diagnostic ability equal to or better than that of conventional wet silver salt light-sensitive materials. The preferred range of conditions is described below.

[0169] (1) Measure the optical density 0.5, 1.0, 1.5 and the minimum optical density of the silver image obtained after heat development processing of the photothermographic material, and CIE 1976 (L * u * v *) The linear coefficient of determination (multiple determination) of the linear regression line created by placing u and V at each optical density above in two-dimensional coordinates, where the horizontal axis of the color space is u * and the vertical axis is V *. ) R2 is preferably from 0.998 to 1.000. Furthermore, it is preferable that the V * value of the intersection with the vertical axis of the linear regression line is 5 to 5, and the slope (v * Zu *) is 0.7 to 2.5.

[0170] (2) Measure the optical density of the photothermographic material of 0.5, 1.0, 1.5 and the lowest optical density, and set the horizontal axis of the CIE 1976 (LW) color space to a *, And the vertical coefficient b * is a two-dimensional coordinate where the a * and b * at each optical density above are placed and the coefficient of determination (multiple determination) R2 of the linear regression line created is between 0.998 and 1.000. Preferably there is. Furthermore, with the vertical axis of the linear regression line It is preferable that the b * value of the intersection point is -5 to 5 and the slope (b * Za *) is 0.7 to 2.5.

[0171] Next, an example of a method for creating the above-described linear regression line, that is, a method for measuring u, v * and a *, b * in the CIE 1976 color space will be described.

[0172] Using a heat development apparatus, prepare a 4-stage wedge sample including unexposed areas and optical densities of 0.5, 1.0, and 1.5. Each wedge density part produced in this way is measured with a spectrocolorimeter (manufactured by Koryo Minolta, Inc .: CM-3600d, etc.), and u, V * or a *, b * are calculated. The measurement conditions at that time are F7 light source as the light source, 10 degree viewing angle, and measurement in the transmission measurement mode. Plot u *, V or a *, b * measured on a graph with u * or a * on the horizontal axis and V * or b * on the vertical axis to obtain a linear regression line, and the coefficient of determination (multiple determination) R2 Find the intercept and slope.

[0173] Next, a specific method for obtaining a linear regression line having the above characteristics will be described.

[0174] In the present invention, it is directly and indirectly involved in the development reaction process of a reducing agent (developer), silver halide grains, aliphatic carboxylic acid silver and the following toning agent. By adjusting the addition amount of the compound or the like, the developed silver shape can be optimized to obtain a preferable color tone. For example, if the developed silver shape is dendritic, it becomes a bluish direction, and if it is a filament shape, it becomes a yellowish direction. That is, the adjustment is made in consideration of the tendency of the developed silver shape.

[0175] Conventionally, phthalazinone or phthalazine, phthalic acids, and phthalic anhydrides are generally used as toning agents. Examples of suitable toning agents are disclosed in RD17029, US Pat. Nos. 4,123,282, 3,994,732, 3,846,136, 4,021,249 and the like.

In addition to such a toning agent, the color tone is adjusted using couplers disclosed in JP-A-11 288057, European Patent 1,134,611A2, etc., and leuco dyes described in detail below. It can also be adjusted. In particular, it is preferable to use a coupler or a leuco dye for fine adjustment of the color tone.

The photothermographic material can also be adjusted in color tone using a leuco dye as described above. The leuco dye is preferably heated at a temperature of about 80 to 200 ° C. for about 0.5 to 30 seconds. In addition, any leuco dye that forms a pigment by being oxidized by an oxidized form of the above reducing agent or the like, which is any colorless or slightly colored compound that is oxidized to a colored form, can be used. Compounds that are pH sensitive and can be oxidized to a colored state are useful.

[0178] Representative leuco dyes suitable for use in the present invention are not particularly limited. For example, biphenol leuco dyes, phenol leuco dyes, indoor-phosphorus leuco dyes, acrylic vinyl leuco dyes, phenoxazine leuco dyes, Nojiazine leuco dye and phenothiazine leuco dye. U.S. Pat.Nos. 3,445,234, 3,846,136, 3,994,732, 4,021,249, 4,021,250, 4,4 No. 022,617, No. 4,123,282, No. 4,368,247, No. 4,461,681, and JP-A-50-36110, JP-A-59-206831, JP-A-5-204087 No. 11-231460, No. 2002-169249, No. 2002-236334, and the like.

[0179] In order to adjust to a predetermined color tone, it is preferable to use leuco dyes of various colors singly or in combination of a plurality of types. In the present invention, the use of a highly active reducing agent changes the color tone (especially yellowishness) depending on the amount and ratio of use, or the use of fine-grain silver halide makes the concentration particularly 2. In order to prevent an image from becoming excessively reddish at a high density portion of 0 or more, it is preferable to use a leuco dye that develops yellow and cyan in combination and adjust the amount of use.

[0180] The color density is preferably adjusted appropriately in relation to the color tone of the developed silver itself. In the present invention, the color is adjusted so as to have a reflection optical density of 0.01 to 0.05 or a transmission optical density of 0.005 to 0.50, and the color tone is adjusted so that an image in the color tone range is preferable. It is preferable. It is preferable that the sum of the maximum densities at the maximum absorption wavelength of the dye image formed by the leuco dye is 0.01 to 0.50, more preferably 0.02 to 0.30, and particularly preferably 0. It is preferable to develop the color so as to have 03 to 0.10.

[0181] (Yellow coloring leuco dye)

The photothermographic material can also be adjusted in color tone using a leuco dye as described above. In the present invention, a color image forming agent that increases the absorbance at 360 to 450 nm when oxidized is preferably used as the yellow color-forming leuco dye. These color image forming agents are particularly preferably color image forming agents represented by the following general formula (YA). [0182] [Chemical Formula 17] General formula (YA>

[0183] In the formula, R represents a substituted or unsubstituted alkyl group, and R represents a hydrogen atom, substituted or unsubstituted.

11 12

The forces R 1 and R 2 representing substituted alkyl or acylamino groups are 2-hydroxyphenyl groups.

11 12

It is never a til group. R represents a hydrogen atom or a substituted or unsubstituted alkyl group.

13

R 1 represents a substituent that can be substituted on the benzene ring.

14

[0184] R represents a substituted or unsubstituted alkyl group, and R represents a substituent other than a hydrogen atom.

11 12

In this case, R represents an alkyl group. The alkyl group is an alkyl group having 1 to 30 carbon atoms.

11

May have a preferred substituent. Specifically, methyl, ethyl, butyl, octyl, i-propyl, t-butynole, t-octyl, t-pentyl, sec-butyl, cyclohexenole, 1-methyl-cyclohexyl and the like are sterically larger than i-propyl. Groups such as i-propyl, i-nonyl, t-butyl, t-amyl, t-octyl, cyclohexyl, 1-methyl cyclohexyl, adamantyl, etc., among which secondary or tertiary alkyl groups are preferred. Particularly preferred are tertiary alkyl groups such as t-butyl, t-octyl, and t-pentyl. Examples of the substituent that R 1 may have include a halogen atom, an aryl group,

11

Examples thereof include an alkoxy group, an amino group, an acyl group, an acylamino group, an alkylthio group, an arylothio group, a sulfonamide group, an acyloxy group, an oxycarbonyl group, a strong rubamoyl group, a sulfamoyl group, a sulfonyl group, and a phosphoryl group.

[0185] R represents a hydrogen atom, a substituted or unsubstituted alkyl group, or an acyl amino group. Al

12

The kill group is preferably an alkyl group having 1 to 30 carbon atoms, and the acylamino group is preferably an acyl group having 1 to 30 carbon atoms. Among them, the explanation of the alkyl group is the same as R. Asyl

11

The amino group may be unsubstituted or substituted, and specific examples include an acetylylamino group, an alkoxyacetylylamino group, an aryloxycetylamino group, and the like. Preferred as R

12 or a hydrogen atom or an unsubstituted alkyl group having 1 to 24 carbon atoms. , I-propyl, t-butyl. R and R are 2-hydroxyphenol

11 12

It is not a ru group.

[0186] R represents a hydrogen atom or a substituted or unsubstituted alkyl group. As an alkyl group

13

The explanation of the alkyl group preferred by the alkyl group having 1 to 30 carbon atoms is the same as that for R.

11

R is preferably a hydrogen atom or an unsubstituted alkyl group having 1 to 24 carbon atoms.

13

Examples include methyl, i-propyl, t-butyl and the like. One of R and R is water

12 13

It is preferable to be an elementary atom.

[0187] R represents a substitutable group on the benzene ring, for example, the substitution in the general formula (RD1)

14

The same group as described for the group R ⁴ . R is preferably a substituted or unsubstituted carbon.

14

They are a C1-C30 alkyl group and a C2-C30 oxycarbonyl group, and a C1-C24 alkyl group is more preferable. Examples of the substituent of the alkyl group include aryl, amino, alkoxy, oxycarbol, acylamino, acyloxy, imide, ureido, aryl, amino, oxycarbonyl and alkoxy. The group is more preferred. These alkyl group substituents may be further substituted with these substituents.

Next, the bisphenol compound represented by the following general formula (YB), which is particularly preferably used in the present invention among the compounds represented by the general formula (YA), will be described.

[0189] [Chemical 18]

[0190] In the formula, Z is —S— or — C (R) (R

21 21 ') — represents R and R

21 21 ′ each represents a hydrogen atom or a substituent. Examples of the substituent represented by R 1 and R ′ include R ^{1 in} the general formula (RDl).

21 21

And the same groups as the substituents mentioned in the above. R, R

21 21 ′ is preferably a hydrogen atom or an alkyl group.

[0191] R 1, R 2, R 'and R' each represent a substituent. The substituent is represented by the general formula (RDl)

22 23 22 23

And the same groups as the substituents mentioned for R ² and R ³ in. [0192] R 1, R 2, R 'and R' are preferably an alkyl group, a alkenyl group or an alkyl group.

22 23 22 23

Group, aryl group, and heterocyclic group, and an alkyl group is more preferable. Examples of the substituent on the alkyl group include the same groups as those described in the description of the substituent in formula (RD1). R, R, R 'and R

22 23 22 23 ′ is more preferably a tertiary alkyl group such as t-butyl, t-pentyl, t-octyl, 1-methyl-cyclohexyl and the like.

[0193] R 1 and R 'each represents a hydrogen atom or a substituent, and examples of the substituent include those represented by the general formula (R

24 24

Examples thereof include the same groups as the substituents exemplified in the description of R ⁴ in D1).

[0194] Examples of the compounds represented by the general formulas (YA) and (YB) include compounds II 1 to -40 described in paragraphs "0032" to "0038" of JP-A-2002-169249, Mention may be made of the compounds ITS-1 to ITS-12 described in paragraph "0026" of European Patent 1,211,093.

[0195] Specific examples of the bisphenol compounds represented by the general formulas (YA) and (YB) are shown below.

1S The present invention is not limited to these.

[0196] [Chemical 19]

[0198] The addition amount of the compound of general formula (YA) (including the compound of hindered dorfolhi compound and the compound of general formula (YB)) is usually 0.0001 to 0.01 mol per mol of silver, preferably Is from 0.0005 to 0.01 mol, more preferably <0.001 to 0.008 mol.

[0199] Further, the molar ratio of the addition ratio of the yellow color-forming leuco dye to the total of the reducing agents is preferably 0.001 to 0.2. More preferred.

[0200] (Cyan coloring leuco dye)

The photothermographic material of the present invention can also be adjusted in color tone using a cyan color-forming leuco dye in addition to the yellow color-forming leuco dye. The cyan chromophoric leuco dye is preferably any colorless or slightly colored compound that oxidizes into a colored form when heated at a temperature of about 80-200 ° C for about 0.5-30 seconds. Any leuco dye that forms a pigment by oxidation with an oxidant of a reducing agent can be used. Compounds that are pH sensitive and can be oxidized to a colored state are useful.

[0201] A color image forming agent that increases the absorbance at 600 to 700 nm when oxidized is preferably used as the cyan color-forming leuco dye. As these compounds, for example, Japanese Patent Application Laid-Open No. 59-206831 (particularly compounds having λ max in the range of 600 to 700 nm), Compounds of general formulas (I) to (IV) of JP-A-5-204087 (specifically, compounds of (1) to (18) described in paragraphs “0032” to “0037”) and JP-A-11-231460 And compounds of the general formulas 4 to 7 (specifically, compounds No. 1 to No. 79 described in the paragraph “0105”)

[0202] The cyan color-forming leuco dye preferably used in the present invention is a compound represented by the following general formula (CLA) or general formula (CLB-I). The color image forming agent represented by the general formula (CLB-I) is particularly preferable in that it can adjust the color tone even when added in a small amount due to its high coloring efficiency and is excellent in image storage stability.

[0203] Hereinafter, the compounds of general formula (CLA) and general formula (CLB-I) will be described in detail.

[0204] [Chemical formula 21] General formula (CLA)

[0205] In the formula, R 1 and R 2 are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, an alkyl,

31 32

Kenyl group, alkoxy group, NHCOR group (R is an alkyl group, aryl group, heterocyclic group

30 30

Represents. Or R 1 and R 2 are connected to each other to form an aliphatic hydrocarbon ring or aromatic carbon

31 32

It is a group that forms a hydrogen ring or a heterocyclic ring. A is — NHCO group, —CONH group or

Three

NHCONH group, R is a substituted or unsubstituted alkyl group, aryl group or

33

Represents a heterocyclic group.

[0206] In addition, -A R may be a hydrogen atom. For example, the —A R moiety represents a hydrogen atom

3 33 3 33

Or A represents one NHCO group, CONH group or one NHCONH group, and R

3 33 represents a substituted or unsubstituted alkyl group, aryl group or heterocyclic group.

[0207] W is a hydrogen atom or —CONHR group, —COOR group or —COOR group (R is substituted or

3 35 35 35 35 represents an unsubstituted alkyl group, aryl group or heterocyclic group. ) And R

34 is a hydrogen atom

, Halogen atom, substituted or unsubstituted alkyl group, alkenyl group, alkoxy group, force Rubamoyl group or -tolyl group is represented. R is CONHR, —COR or CO

36 37 37

OR group (R represents a substituted or unsubstituted alkyl group, aryl group or heterocyclic group.)

37 37

X represents a substituted or unsubstituted aryl group or heterocyclic group.

Three

[0208] In the general formula (CLA), examples of the halogen atom represented by R 1 and R 2 include fluorine atom

31 32

The alkyl group includes alkyl groups having up to 20 carbon atoms (methyl group, ethyl, butyl, dodecyl, etc.), and the alkyl group includes carbon atoms. Up to 20 alkenyl groups (bule, allyl, butyl, hexyl, hexagenole, etheninore 2 propenole, 3 butenore, 1-methylolene 3 propenyl, 3 pentale, 1-methyl-3 butyr, etc.) Examples of the alkoxy group include alkoxy groups having up to 20 carbon atoms (methoxy, ethoxy, etc.). In addition, the alkyl group represented by R in the NHC OR group is an alkyl group having up to 20 carbon atoms.

30 30

Group (methyl, ethyl, butyl, dodecyl, etc.), and aryl groups include phenyl and naphthyl.

Groups having 6 to 20 carbon atoms such as ruthenium, and examples of the heterocyclic group include chenyl, furyl, imidazolyl, pyrazolyl, pyrrolyl and the like. An alkyl group represented by R

33

Is preferably an alkyl group having up to 20 carbon atoms, for example, methyl, ethyl, propyl, dodecyl, etc., and the aryl group is preferably an aryl group having 6 to 20 carbon atoms, such as phenol. And heterocyclic groups include, for example, chael, furyl, imidazolyl, pyrazolyl, pyrrolyl and the like.

[0209] In the CONHR group, COR group or COOR group represented by W, represented by R

The alkyl group is preferably an alkyl group having up to 20 carbon atoms, and examples thereof include methyl, ethyl, butyl, dodecyl and the like, and the aryl group preferably has from 6 to 20 carbon atoms. Examples of the aryl group include phenyl and naphthyl, and examples of the heterocyclic group include chenyl, furyl, imidazolyl, pyrazolyl and pyrrolyl.

[0210] Examples of the halogen atom represented by R include fluorine, chlorine, bromine, iodine and the like.

34

Examples of the alkyl group include chain or cyclic alkyl groups such as methyl, butyl, dodecyl, cyclohexyl and the like, and examples of the alkenyl group include alkenyl groups having up to 20 carbon atoms (bulu, allyl, butyr, Hexane, Hexagel, Etul 2 Lopeninole, 3-butenyl, 1-methyl-3-propenyl, 3-pentenyl, 1-methyl-3-butenyl, etc.), and examples of alkoxy groups include methoxy, butoxy, tetradecyloxy, Examples thereof include jetyl carbamoyl, phenol carbamoyl and the like. A nitrile group is also preferred. Among these, a hydrogen atom and an alkyl group are more preferable.

[0211] R 1 and R 2 may be linked to each other to form a ring structure. The above groups are further single

33 34

It can have a substituent or a plurality of substituents. Typical substituents include halogen atoms (fluorine, chlorine, bromine, etc.), alkyl groups (methyl, ethyl, propyl, butyl, dodecyl, etc.), hydroxyl groups, cyano groups, nitro groups, alkoxy groups (methoxy, ethoxy). Etc.), alkylsulfonamide groups (methylsulfonamide, octylsulfonamide, etc.), arylsulfonamides (phenylsulfonamide, naphthylsulfonamide groups, etc.), alkylsulfamoyl groups (ptylsulfamoyl etc.), arylsulfa Moyl (phenylsulfamoyl, etc.), alkyloxycarbonyl group (methoxymethoxy, etc.), aryloxycarboro group (phenoloxycarbol, etc.), aminosulfonamide group, acylamino group, carbon Vamoyl, sulfol, sulfiel, sulfoxy, sulfo, Ruoki sheet group, alkoxy group, alkyl carboxymethyl - group, Arirukarubo - group, Aminokarubo - group, and the like.

[0212] R or R is preferably a phenol group, more preferably a halogen atom or cyan.

30 35

A full group having a plurality of groups as substituents.

[0213] In a CONHR group, COR group or COOR group represented by R, represented by R

The alkyl group having 36 to 37 37 37 is preferably an alkyl group having up to 20 carbon atoms, and examples thereof include methyl, ethyl, butyl, dodecyl and the like. The aryl group is preferably an aryl group having 6 to 20 carbon atoms. Examples thereof include phenol, naphthyl and the like, and examples of the heterocyclic group include chenyl, furyl, imidazolyl, pyrazolyl, pyrrolyl and the like.

[0214] Examples of the substituent that the group represented by R can have include R 1 to R 5 in the general formula (CLA).

37 31 34 The same substituents as mentioned in the description can be used.

[0215] The aryl group represented by X has 6 to 20 carbon atoms such as phenol and naphthyl.

Three

And heterocyclic groups include, for example, chenyl, furyl, imidazolyl, and pyridine. Examples include lazolyl and pyrrolyl. As a substituent that the group represented by X can have

Three

Is the same as the substituents mentioned in the explanation of R to R in the general formula (CLA).

31 34

Can do. As the group represented by X, an alkylamino group (such as jetylamino) at the para position

Three

Preferred are aryl groups or heterocyclic groups having.

[0216] These groups may include photographically useful groups.

Specific examples of cyan color-forming leuco dye (CLA) are shown below, but the cyan color-forming leuco dye used in the present invention is not limited to these examples.

[0218] [Chemical 22]

twenty three]

Four]

[0221] Next, the compound represented by the general formula (CLB-I) will be described. The compound represented by the general formula (CLB-I) is preferably a compound represented by the following general formula (CLB-II) or (CLB-III), and most preferably a compound represented by (CLB-III). Masle.

First, the compound represented by the general formula (CLB—I) will be described.

[0223] [Chemical 25] —General formula (CLB— 1>

[0224] In the formula, R 1, R 2, R 3 and R 4 are each a hydrogen atom, an aliphatic group, an aromatic group, an alkoxy group

41 42 40a 40b

Represents a group, an aryloxy group, an acylamino group, a sulfonamide group, a strong rubermoyl group, or a halogen atom. R is a hydrogen atom, aliphatic group, aromatic group, acyl group, alkoxycarbon

43

Represents an alkyl group, an aryloxycarboquinyl group, a strong rubamoyl group, a sulfamoyl group, or a sulfonyl group. X X

41 and 42 represent a substitutable group on the benzene ring. m41 and m42

Represents an integer from 0 to 5. If m41 and m42 are 2 or more, multiple Xs and Xs may be the same

41 42 May be different.

[0225] Specific examples of the aliphatic group represented by R 1, R 2, R 3 and R 4 include an alkyl group, an alkyl group,

41 42 40a 40b

Examples thereof include hydrocarbon groups such as a nyl group and an alkynyl group. These hydrocarbon groups preferably have 1 to 20 carbon atoms, more preferably 1 to 20 carbon atoms. Examples of the alkyl group having 1 to 25 carbon atoms include methyl, ethyl, propyl, i-propyl, t-butyl, pentyl, hexyl, cyclohexyl, etc., and examples of the cycloalkyl group include cyclohexyl, cyclopentyl group, etc. As the alkyl group, Etul 2 -probe, 3 -butur, 1-methyl 3-probe, 3-pentyl, 1-methyl 3-butur, etc. 1Probule, propargyl, etc.

[0226] Specific examples of the aromatic group represented by R 1, R 2, R 3 and R 4 include an aryl group (phenol).

41 42 40a 40b

, Naphthyl, etc.) and heterocyclic groups (pyridyl, thiazolyl, oxazolyl, imidazolyl, furyl, pyrrolyl, pyrazyl, pyrimidinyl, pyridazyl, selenazolyl, sriphoral, piperidinyl, pyrazolyl, tetrazolyl, etc.).

[0227] Specific examples of the alkoxy group include methoxy, ethoxy, i-propoxy group, t-butoxy group. Specific examples of the isotropic aryloxy group include phenoxy and naphthyloxy isosyl. As the acyl amino group, acetylamino-containing benzoylamino and the like, and specific examples of the sulfonamide group include methanesulfonamide, butanesulfonamide, octanesulfonamide, Benzenesulfonamide, etc., has the following rubamoyl groups: aminoamino, methylaminocarbonyl, dimethylaminocarbonyl, propylaminocarbonyl, pentylaminocarbonyl

Cyclohexylaminocarbonyl, phenylaminocarbonyl, 2-pyridylaminocarbonyl and the like.

[0228] The halogen atom is chlorine, bromine or iodine.

[0229] R 1 and R 2 are preferably aliphatic groups, alkoxy groups, aryloxy groups, and more preferably.

41 42

Or an alkyl group or an alkoxy group, more preferably a secondary or tertiary alkyl group or an alkoxy group.

[0230] R 1 and R 2 are preferably a hydrogen atom, an aliphatic group, more preferably a hydrogen atom.

40a 40b

[0231] Examples of the aliphatic group, aromatic group, alkoxy group, and aryloxy group represented by R include

43

In the above R 1 and R 2, groups exemplified as specific examples can be exemplified.

41 42

[0232] Specific examples of the acyl group represented by R include acetyl, propionyl, butanol, and

43

Xanoyl, cyclohexanoyl, benzoyl, pyridinoyl and the like can be mentioned.

[0233] Specific examples of the alkoxycarbonyl group represented by R include a methoxycarbonyl group,

43

Examples thereof include a toxicarbol group and a t-butoxycarbonyl group.

[0234] Specific examples of the arylcarbonyl group represented by R include phenoxycarboro.

43

Examples of the powerful rubamoyl group include amino carbonate, methylaminocarbonyl, dimethylaminocarbonyl, propylaminocarbonyl, pentylaminocarbonyl, cyclohexylaminocarbonyl, phenylaminocarbonyl, and the like. , 2-pyridylamino force, and the like. Examples of the sulfamoyl group include methylsulfamoyl, dimethylsulfamoyl, and phenylsulfamoyl. Examples of the sulfol group include methylsulfonyl, butylsulfol, and octylsulfo- And the like.

[0235] R is preferably a hydrogen atom, an alkyl group, or an acyl group, more preferably a hydrogen atom or carbon.

43

It is a 1 to 10 prime alkyl group or an acyl group.

[0236] Specific examples of the substitutable group on the benzene ring represented by X and X include 1 carbon atom. ˜25 alkyl groups (methyl, ethyl, propyl, isopropyl, t-butyl, pentyl, hexylcyclohexyl, etc.), cycloalkyl groups (cyclohexyl, cyclopentyl, etc.), alkenyl groups (bulu, allyl, butenyl, hexyl) Kiseru, Hexager, Etul

—2 propenyl, 3 butenyl, 1-methyl 3 propenyl, 3 pentenyl, 1-methyl-3-butul, etc.), alkyl groups (such as etul, propargyl), glycidyl groups, attalylate groups, metatalylate groups, Aryl groups (such as phenol and naphthyl), heterocyclic groups (such as pyridyl, thiazolyl, oxazolyl, imidazolyl, furyl, pyrrolyl, pyrajur, pyrimidinyl, pyridazyl, selenazolyl, sriphoral, piperidyl, pyrazolyl, tetrazolyl Etc.), halogen atoms (chlorine, bromine, iodine, fluorine, etc.), alkoxy groups (methoxy, ethoxy, propyloxy, pentyloxy, cyclopentyloxy, hexyloxy, cyclohexoxy, etc.), aryloxy groups (phenoxy, etc.), alkoxycarbonyl groups (Methyloxycarbonyl, ethylo Xyloxycarbonyl, butyloxycarbonyl, etc.), aryloxycarbonyl groups (such as phenylcarboxyl), sulfonamide groups (methanesulfonamide, ethanesulfonamide, butanesulfonamide, hexanesulfonamide, cyclohexanesulfonamide, Benzenesulfonamide, etc.), sulfamoyl group (aminosulfonyl, methylaminosulfonyl, dimethylaminosulfonyl, butylaminosulfonyl, hexylaminosulfonyl, cyclohexylaminosulfonyl, phenylaminosulfonyl, 2-pyridylaminosulfol, etc.), ureido Groups (methylureido, ethylureido, pentylureido, cyclohexylureido, feruleureido, 2-pyridylureido, etc.), acyl groups (acetylyl, propionyl, butanoyl) , Hexanol, cyclohexanol, benzoyl, pyridinoyl, etc.), rubamoyl group (amino carbonyl, methylamino carbonyl, dimethylaminocarbonyl, propylamino carb)

Borol, pentylaminocarbol, cyclohexylaminocarbole, phenylaminocarbole, 2-pyridylaminocarbol, etc.), amide group (acetamido, propionamido, butanamido, hexaneamido, benzamido) ), Sulfo group (methylsulfol, ethinolesnorehoninore, butinolesnorehoninore, cyclohexenoresnorehoninore, pheninolesnorehoninole, 2-pyridylsulfol, etc.), sulfone Amide group (methylsulfonamide, octylsulfonamide, phenylsulfonamide, naphthylsulfonamide, etc.), amino group (amiethyl ester) Dimethylamino-containing butylamino, cyclopentylamino-containing 2-pyridylamino, etc.), cyano group, nitro group, sulfo group, carboxyl group, hydroxyl group, oxamoyl group and the like. These groups may be further substituted with these groups.

[0237] X and X are preferably an alkoxy group, an aryloxy group, a strong rubamoyl group, an amide

41 42

Group, sulfonamido group, amino group, more preferably alkoxy group, amino group.

[0238] Next, among the compounds represented by the general formula (CLB—I), a general formula (CLB

The compounds represented by II) and general formula (CLB-III) are described below.

[0239] [Chemical 26]

[0240] In the formula, R 1, R 2 and R 3 have the same meanings as R 1, R 2 and R in the above general formula (CLB—I), respectively.

41 42 43 41 42 43 X and X are each an aliphatic group, aromatic group, amino group, alkoxy group or arylo group.

43 44

Represents a xy group.

[0241] Aliphatic group, aromatic group, amino group, alkoxy group, aryloxy represented by X and X

43 44

Examples of the silyl group include an aliphatic group, an aromatic group represented by X and X in the general formula (CLB—I),

41 42

Examples thereof include the same groups as the specific examples of the amino group, alkoxy group and aryloxy group. X and X

43 is preferably an alkoxy group, an aryloxy group or an amino group, more preferably

44

A alkoxy group and an amino group;

[0242] R 1, R 2, R 3 and R 4 each represent a hydrogen atom or an alkyl group. Tool of the alkyl group

44 45 46 47

Examples include methyl, ethyl, propyl, i-propyl, t-butyl, pentyl, hex And the like. These groups may have a substituent at an arbitrary position. Examples of the substituent include those exemplified as the substituent in the general formula (CLB-I). R 1, R 2, R and R are preferably an alkyl group having 1 to 10 carbon atoms, more preferably

44 45 46 47

Is methyl, ethyl.

[0243] The compounds represented by the general formulas (CLB-I) to (CLB-III) can be easily synthesized by a conventionally known method such as the method described in JP-B-7-45477. Hereinafter, the power of the present invention is not limited to these examples showing specific examples of leuco dyes represented by the general formulas (CLB-I) to (CLB-III).

[0244] [Chemical 27]

[§] "02458

C c-

4 CH

One {i One) B2_> B CLB3CLc—I—

[62 ^] [9W0]

(ΖΙ-βΊ0) (U-βΊ) (oi.-ano)

LZl90 / L00Zdr / 13d εζ

[0247] [Chemical 30]

(CLB— 37) (CLB-38) (CLB-39)

(CLB— 40) (CLB-41) (CLB -42)

32]

[0250] [Chemical 33]

[0251] The amount of the cyan chromophoric leuco dye added is usually from 0.0001 to 0.05 mole per mole of silver, preferably 0.005 to 0.02 monolayer, more preferably 0.00. 001 ~ 0.01 Mono. The ratio of the added amount of cyan chromogenic leuco dye to the total of the reducing agents is 0.001 to 0.2 force girls, and 0.005 to 0.1 force girls.

The photothermographic material of the present invention has a maximum absorption of a dye image formed with a cyan leuco dye. It is preferable to set the sum of the maximum densities at the collection wavelength to be 0.01-0.50, more preferably 0.02-0.30, particularly preferably 0.03-0.10. Rikishi.

[0253] In the present invention, a subtle color tone can be adjusted by using a magenta chromogenic leuco dye or a yellow chromogenic leuco dye in combination with the cyan chromogenic leuco dye.

[0254] The yellow color-forming leuco dye and the cyan color-forming leuco dye represented by the general formulas (YA) and (YB) may be added by a reducing agent addition method represented by the general formula (1). It can be added by the same method, and it can be added to the coating solution by any method such as solution form, emulsified dispersion form, solid fine particle dispersion form, etc.

[0255] The reducing agent of the general formula (1), the yellow coloring leuco dye and the cyan coloring leuco dye of the general formula (YA), (YB) are contained in a photosensitive layer containing an aliphatic carboxylic acid silver salt. Although it is preferable that one is contained in the photosensitive layer and the other may be contained in the non-photosensitive layer adjacent to the photosensitive layer, or both may be contained in the non-photosensitive layer. If the photosensitive layer is composed of a plurality of layers, each layer may be contained in a separate layer.

[0256] (Silver saving agent)

The photosensitive layer or the non-photosensitive layer according to the present invention may contain a silver saving agent. As used herein, a silver saving agent refers to a compound that can reduce the amount of silver necessary to obtain a certain silver image density.

[0257] Although various mechanisms for the function of reducing the necessary silver amount are conceivable, a compound having a function of improving the covering power of developed silver is preferred. Here, the covering power of developed silver means the optical density per unit amount of silver. This silver saving agent can be present in the photosensitive layer, the non-photosensitive layer, or any of them. Preferred examples of the silver saving agent include hydrazine derivative compounds, vinyl compounds, phenol derivatives, naphthol derivatives, quaternary onium compounds, and silane compounds. Specific examples include silver saving agents disclosed in paragraphs “0195” to “0235” of JP-A-2003-270755.

[0258] As the silver saving agent according to the present invention, particularly preferred silver saving agents are compounds represented by the following general formulas (SE1) and (SE2). [0259] General formula (SE1)

Q -NHNH-Q

1 2

In the formula, Q is an aromatic group bonded to NHNH Q at the carbon atom site, or a heterocycle

1 2

Q represents a strong rubamoyl group, an acyl group, an alkoxy carbo group, an aryl group.

2

Shikar

A bonyl group, a sulfonyl group, or a sulfamoyl group is represented.

[0260] [Chemical Formula 34] General formula (SE2)

[0261] In the formula, R represents an alkyl group, an acyl group, an acylamine group, a sulfonamide group, an alkoxy group, a carbonyl group, or a group of rubamoyl groups. R ¹² represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkylthio group, an arylothio group, an acyloxy group, or a carbonate group. R ¹³ and R ¹⁴ each represent a group that can be substituted on the benzene ring. R ¹³ and R ¹⁴ may be linked to each other to form a condensed ring.

[0262] In the general formula (SE2), when R ¹³ and R "are connected to each other to form a condensed ring, the condensed ring is particularly preferably a naphthalene ring. The general formula (SE2) is a naphthol-based compound. In some cases, R ¹¹ is preferably a strong rubamoyl group, particularly preferably a benzoyl group, and R ¹² is particularly preferably an alkoxy group, preferably an alkoxy group or an aryloxy group. Better!/,.

[0263] (Thermal solvent)

The photothermographic material of the present invention preferably contains a thermal solvent. Here, the thermal solvent is defined as a material capable of lowering the heat development temperature by 1 ° C. or more compared to a heat-developable photosensitive material containing no heat solvent. More preferred are materials that can lower the heat development temperature by 2 ° C or more, and particularly preferred are materials that can lower the temperature by 3 ° C or more. For example, a photothermographic material A containing a thermal solvent is different from a photothermographic material A containing a thermal solvent. When the photothermographic material containing B is a photothermographic material, the photothermographic material is exposed to the photothermographic material B and processed at a heat developing temperature of 120 ° C and a heat developing time of 20 seconds. A heat solvent is used when the heat development temperature for A with the same exposure and heat development time is 119 ° C or less. The thermal solvent has a polar group as a substituent and is preferably represented by the general formula (TS), but is not limited thereto.

[0264] General formula (TS)

(Y) nZ

In the general formula (TS), Y represents an alkyl group, an alkyl group, an alkyl group, an aryl group or a heterocyclic group. Z is a hydroxyl group, carboxy group, amino group, amide group, sulfonamide group, phosphoric acid amide group, cyano group, imide, ureido, sulfoxide, sulfone, phosphine, phosphinoxide or nitrogen-containing heterocyclic group. Represents. n represents an integer of 1 to 3, which is 1 when Z is a monovalent group, and is the same as the valence of Z when Z is a divalent or higher group. When n is 2 or more, multiple Ys may be the same or different.

[0265] Y may further have a substituent, and may have a group represented by Z as a substituent. Y will be described in more detail. In the general formula (TS), Y is a linear, branched or cyclic alkyl group (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 25 carbon atoms such as methyl, ethyl, n -Propyl, iso-propyl, sec-butyl, t-butyl, t-octyl, n-amyl, t-amyl, n-dodecyl, n-tridecyl, octadecyl, icosyl, docosyl, cyclopentyl, cyclohexyl, etc. ), An alkenyl group (preferably having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, particularly preferably 2 to 25 carbon atoms such as vinyl, aryl, 2-butyl, and 3-pentale). ), Aryl groups (preferably having 6 to 40 carbon atoms, more preferably 6 to 30 carbon atoms, particularly preferably 6 to 25 carbon atoms such as phenol, p-methylphenol, and naphthyl). , Heterocyclic group (Preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms such as pyridyl, virazil, imidazolyl and pyrrolidyl). These substituents may be further substituted with other substituents. These substituents may be bonded to each other to form a ring. [0266] Examples of the substituent which Y may further have a substituent include the substituent described in "0015" of JP-A-2004-21068. The reason why development activity is achieved by using a hot solvent is that the hot solvent melts near the development temperature, so that it is compatible with the substances involved in the development, and the temperature is lower than when no thermal solvent is added. This is thought to be possible in order to make the reaction possible. Thermal development is a reduction reaction involving a highly polar carboxylic acid or silver ion transporter, so it has a polar group! / Is preferred to form ヽ.

[0267] The thermal solvent preferably used in the present invention has a melting point of 50 ° C or higher and 200 ° C or lower, more preferably 60 ° C or higher and 150 ° C or lower. In particular, in a photothermographic material that emphasizes stability to an external environment such as image storage stability, which is the object of the present invention, a thermal solvent having a melting point of 100 ° C. or higher and 150 ° C. or lower is preferable.

[0268] Specific examples of the thermal solvent include compounds described in "0017" of JP-A-2004-21068, compounds described in "0027" of US Published Patent No. US2002Z0025498, MF-1 to MF-3 MF6, MF-7, MF-9 to MF-12, MF-15 to MF-22.

[0269]添力卩量thermal solvent in the present invention is 0. 01~5. Og / m ² is preferred instrument than good Mashiku be the 0.1 05-2 at. 5g / m ^2, more preferably Is between 0.1 and 1.5 g / m ² . The thermal solvent is preferably contained in the photosensitive layer. Moreover, although the said thermal solvent may be used independently, you may use it in combination of 2 or more type. In the present invention, the thermal solvent may be contained in the coating solution by any method such as a solution form, an emulsion dispersion form, or a solid fine particle dispersion form, and may be contained in the photosensitive material.

[0270] As a well-known emulsification dispersion method, an oil such as dibutyl phthalate, tricresyl phosphate, glyceryl triacetate or jetyl phthalate, or a co-solvent such as ethyl acetate or cyclohexanone is used. And a method of mechanically preparing an emulsified dispersion.

[0271] In addition, as a method for dispersing solid fine particles, a powder of a hot solvent is dispersed in an appropriate solvent such as water by a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill or ultrasonic waves, and solid dispersion is performed. The method of producing a thing is mentioned. In that case, protection Colloids (for example, polyvinyl alcohol) and surfactants (for example, surfactants such as sodium triisopropylnaphthalene sulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. In the mills described above, beads such as zirconium are usually used as a dispersion medium, and Zr and the like eluted from these beads may be mixed in the dispersion. Although it depends on the dispersion conditions, it is usually in the range of lppm to 1000ppm. If the Zr content in the photosensitive material (photothermographic material) is 0.5 mg or less per lg of silver, there is no practical problem. The aqueous dispersion preferably contains a preservative (eg, benzoisothiazolinone sodium salt).

[0272] (Anti-capricious agent, image stabilizer)

In any of the constituent layers of the photothermographic material of the present invention, an anti-capri agent for preventing the occurrence of force preserving during storage before heat development, and an image stabilization for preventing image deterioration after heat development. It is preferable to contain an agent. Hereinafter, the anti-capri and image stabilizer that can be used in the present invention will be described.

[0273] Since reducing agents having protons such as bisphenols and sulfonamidophenols are mainly used as reducing agents, these hydrogens are stabilized and the reducing agents are deactivated. It is preferable that a compound capable of preventing and preventing the reaction of reducing silver ions is contained. Also, silver atoms generated when raw film and images are stored! / It is preferable that a compound capable of acid bleaching tanned metallic silver (silver cluster) is contained. As specific examples of compounds having these functions, for example, biimidazolyl compounds, ododonium compounds and halogen atoms described in paragraphs “0096” to “0128” of JP-A-2003-270755 are released as active species. List possible compounds.

[0274] Further, a polymer having at least one monomer repeating unit having a halogen radical releasing group as disclosed in JP-A-2003-91054, a vinyl described in paragraph "0013" of JP-A-6-208192, Preferable specific examples include sulfone and Z or j8-halosulfone, and various capri prevention and image stabilizers such as vinyl type inhibitors having an electron withdrawing group described in JP-A-2005-107496. .

[0275] When the reducing agent used in the present invention has an aromatic hydroxyl group (-OH), particularly in the case of bisphenols, it has a group capable of forming a hydrogen bond with these groups. It is preferable to use a non-reducing compound in combination. Specific examples of particularly preferred hydrogen bonding compounds in the present invention include, for example, paragraphs “0061” to “0” of JP-A-2002-90937.

Compound (II 1) to (II 40) described in “064”.

[0276] On the other hand, many compounds that can release a halogen atom as an active species are known as an anti-capri and image stabilizer. Specific examples of the column f of the compounds that generate these active halogen atoms include compounds of general formula (9) described in paragraphs “0264” to “0271” of JP-A-2002-287299.

[0277] The amount of these compounds added is preferably within a range in which the increase in printout silver due to the formation of halogenated silver due to the reaction of halogen released from the compound with silver ions does not become a problem. Specific examples of compounds that generate these active halogen atoms include compounds (III-1) to (III) described in paragraphs “0086” to “0087” of JP-A-2002-169249 in addition to the above-mentioned patents. — 23), compounds described in paragraphs “0031” to “0034” of JP2003-50441 1-la to l-lo, 1 2a to l 2o, compounds described in paragraphs “0050” to “0056” 2a to 2z, 2aa to 211, 2-la to 2-lf, JP-A 2003-91054, paragraphs “0055” to “0058”, compounds 4 1 to 4 32, paragraphs “0069” to “0072” The compounds 5-1 to 5-10 can be mentioned.

[0278] Examples of the capri inhibitor preferably used in the present invention include compound examples a to j described in paragraph "0012" of JP-A-8-314059, and paragraph "0028" of JP-A-7-209797. Thiosulfonate esters A to K, compound examples (1) to (44) described from page 14 of JP-A-55-140833, compounds described in paragraph “0063” of JP-A-2001-13627 (I — (1) to (I 6), (C 1) to (C 3) described in paragraph “0066”, compounds (III 1) to (III 108) described in paragraph “00 27” of JP-A-2002-90937, As compounds of vinyl sulfones and Z or β-halosulfones, compounds described in paragraph “0013” of JP-A-6-208192, VS—1 to VS-7, compound HS—1 to HS-5, sulfo-benzotriazole Compound KS-1 to KS-8 as described in JP-A-2000-330235, and substituted propene nitrile compound as PR-20 as described in JP-T 2000-515995 Examples include PR-08 and compounds (1) 1 to (1) 132 described in paragraphs “0042” to “0051” of JP-A-20 02-207273. [0279] In general, the anti-capri agent is used in an amount of at least 0.001 mol per mol of silver. Usually, the range is 0.01 to 5 moles, preferably 0.02 to 0.6 moles of compound per mole of silver.

[0280] In addition to the above compounds, the photothermographic material may contain various compounds conventionally known as anti-capriformants, but has the same reaction activity as the above compounds. Even if it is a compound which can produce | generate a seed | species, the compound from which a capri prevention mechanism differs may be sufficient. For example, U.S. Pat.Nos. 3,589,903, 4,546,075, 4,452,885, JP-A-5-57234, U.S. Pat.No. 3,874,946, 4,756,999 And compounds described in JP-A-9-288328 and JP-A-9-90550. Further, other antifoggants include compounds disclosed in US Pat. No. 5,028,523 and European Patents 600,587, 605,981, and 631,176.

[0281] (Activator 'Slip agent)

(Fluorine surfactant)

In the present invention, a fluorine-based surfactant represented by the following general formula (SF) is used in order to improve film transportability and environmental suitability (accumulation in a living body) in a laser imager (heat development processing apparatus). Is preferably used.

[0282] General formula (SF)

(Rf- (Lf)-) — (Yf) — (Af)

nl pi ml ql

In the formula, Rf represents a substituent containing a fluorine atom, Lf represents a divalent linking group having no fluorine atom, and Yf represents a (pi + ql) -valent linking group having no fluorine atom. Af represents a cation group or a salt thereof, nl and ml each represents an integer of 0 or 1, pi represents an integer of 1 to 3, and ql represents an integer of 1 to 3. However, when ql is 1, nl and ml are not 0 at the same time.

[0283] In the general formula (SF), examples of the substituent containing a fluorine atom represented by Rf include a fluorinated alkyl group having 1 to 25 carbon atoms (trifluoromethyl, trifluoroethyl, perfluoroethyl, fluorobutinole, perfluorooctinole. Perfluorododecinole and perfluorooctadecyl) or a fluorinated group (perfluoroprobe, perfluorobutur, perfluoronone and perfluorododecyl, etc.). Rf preferably has 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms. Rf is 2-12 fluorine atoms Preferably, the number of fluorine atoms is 3-12.

[0284] Divalent linking groups having no fluorine atom represented by Lf include, for example, alkylene groups (methylene, ethylene, butylene, etc.), alkyleneoxy groups (methyleneoxy, ethyleneoxy, butyleneoxy, etc.), oxyalkylenes, etc. Group (oxymethylene, oxyethylene, oxybutylene, etc.), oxyalkyleneoxy group (oxymethyleneoxy, oxyethyleneoxy, oxyethyleneoxyethyleneoxy, etc.), phenylene group, oxyphenylene group , A phenyl group, an oxyphenyl group, or a group obtained by combining these groups.

[0285] Af represents the power of a cation group or a salt thereof, for example, a carboxyl group or a salt thereof (a sodium salt, a potassium salt and a lithium salt), a sulfo group or a salt thereof (a sodium salt, a potassium salt and a lithium salt), sulfuric acid And a non-festel group or a salt thereof (sodium salt, potassium salt and lithium salt), a phosphoric acid group or a salt thereof such as thorium salt and potassium salt thereof, and the like. Examples of the (pi + ql) -valent linking group having no fluorine atom represented by Y include, for example, a trivalent or tetravalent linking group having no fluorine atom and a nitrogen or carbon atom as the center. A group of atoms. nl represents an integer of 0 or 1, and is preferably 1.

[0286] The fluorine-based surfactant represented by the general formula (SF) is an alkyl compound having 1 to 25 carbon atoms into which a fluorine atom is introduced (trifluoromethyl, pentafluoroethyl, perfluorobutyl, perfluorooctyl and perfluorooctyl). A compound having a lotadecyl, etc.) and an alkenyl compound (a compound having perfluorohexenyl, perfluorononenyl, etc.) and a fluorine atom, respectively, a tri- to hexavalent alkanol compound, a hydroxyl group The compound obtained by addition reaction or condensation reaction with 3 to 4 aromatic compounds or hetero compounds (partially Rf-modified alkanol compounds) is further added to, for example, sulfate ester compounds. It can be obtained by introducing a cation group (Af) by means such as 匕.

[0287] Examples of the tri- to hexavalent alkanol compound include glycerin, pentaerythritol, 2-methyl-2-hydroxymethyl 1,3-propanediol, 2,4-dihydroxy-3-hydroxymethylpentene, 1, 2, 6-hexanetriol, 1, 1, 1-tris (hydroxymethyl) propane, 2,2-bis (butanol) -3, aliphatic triol, tetramethylolmethane, D-sorbitol, xylitol, D-man -Tall and so on. In addition, the above hydroxy Examples of aromatic compounds and hetero compounds having 3 to 4 sil groups include 1,3 5-trihydroxybenzene (fluorodalcine) and 2 4 6-trihydroxypyridine.

[0288] Preferred examples of the fluorine-based surfactant represented by the general formula (SF) are shown below.

[0289] [Chemical 35]

SF- 1 SF— 2

SF— 3 SF— 4

CH ₂ OC ₉ F ₁₇

CH— CH ₂ OS0 ₃ Li C ₉ F ₁₇ OCH ₂ -C-CH ₂ OS0 ₃ Li

CH ₂ OS0 ₃ Li CH ₂ OS0 ₃ Li

SF—5 SF—6

SF SF— 8 3Li

SF— 9 SF— 10

CH ₂ OC3F CH ₃

CH ₂ CHOS0 ₃ Li

CH— OS0 ₃ Na CH— CH ₂ OC ₈

CH ₂ CHOS0 ₃ Li

CH ₂ CH ₃

CH ₂ OS0 ₃ Na

[0290] [Chemical 36] SF— 11 SF— 12

CH ₂ OC ₈ F ₁₇ CH2OC12F 5

CaF, ₇ OCH ₂ 1 C 1 CH ₂ OS0 ₃ Li C ₁₂ F _2S OCH ₂ -C-CH ₂ OS0 ₃ Li

CH ₂ OS0 ₃ Li CH ₂ OS0 ₃ Li

-13 —14

SF- 15 SF— 16

O CH ₂ OC ₈ F ₁₇ CH ₂ OS0 ₃ Li

LiOSCH ₂ — C— CH ₂ OS0 ₃ Li Re 6 13OCH2— One CHsOC ^ Fis

O CH ₂ OS0 ₃ Li CH ₂ OS0 ₃ Li

-17-18

Li0 ₃ S— C ₃ F _& — S0 ₃ Li Li0 ₅ SC ₄ h ₈ — SO3L1

science fiction

CHjCOOCH ₂ (CF ₂ CF ₂ ) ₃ H

₃ S-CHCOOCH ₂ (CF ₂ CF ₂ ) ₃ H

SF 21 C ₂ H ₅

CH ₂ COOCH ₂ CHC ₄ H ₉

Na0 ₃ S-CHCOOCH ₂ CH, {CF ₂ CF ₂ ) 3-H

[0291] As a method of adding the fluorine-based surfactant represented by the general formula (SF) to the coating solution, it can be added according to a known addition method. That is, it can be dissolved in an alcohol such as methanol or ethanol, a ketone such as methyl ethyl ketone or acetone, or a polar solvent such as dimethylsulfoxide or dimethylformamide. In addition, fine particles of 1 m or less can be added by dispersing in water or an organic solvent by sand mill dispersion, jet mill dispersion, ultrasonic dispersion or homogenizer dispersion. Regarding the fine particle dispersion technique, many techniques have been disclosed. The fluorine-based surfactant represented by the general formula (SF) is preferably added to the outermost protective layer.

[0292] The addition amount of the fluorine-based surfactant represented by the general formula (SF) is lm ² per 1 X 10- ⁸ ~1 X 1 0 ¹ mole preferably tool 1 X 10- ⁵ 1 X 10- mol are particularly preferred. If the range is less than the former range, the charging characteristics may not be obtained. If the range exceeds the former range, humidity dependence is high, and the storage stability under high humidity may deteriorate.

[0293] (Surface property modifier)

The photothermographic material is used in the manufacturing process such as coating, drying, processing, etc., when the photosensitive material is scraped, turned over, brought into contact with various devices during transportation, or between the photosensitive surface and the backing surface. The contact between photosensitive materials is often undesirably affected. For example, the surface of the photosensitive material may be scratched or slipped, or the photosensitive material may be transported in a developing device or the like.

[0294] Therefore, in the photothermographic material, in order to prevent scratches on the surface and deterioration in transportability, any one of the constituent layers of the material, particularly on the support. It is preferable that the outermost layer contains a lubricant, a matting agent or the like to adjust the surface physical properties of the photosensitive material.

[0295] In the photothermographic material of the invention, the outermost layer on the support contains organic solid lubricant particles having an average diameter of l30 / zm, and these organic solid lubricant particles are dispersed by a polymer dispersant. This is what it is. The melting point of the lubricant particles is preferably higher than the heat development processing temperature, preferably 80 ° C or higher, more preferably 110 ° C or higher.

[0296] As the organic solid lubricant particles used in the present invention, compounds that lower the surface energy are preferred. For example, polyethylene, polypropylene, polytetrafluoroethylene, and copolymers thereof are pulverized. Examples thereof include formed particles. Examples of organic solid lubricant particles having polyethylene and polypropylene power include polytetrafluoroethylene, polypropylene / polyethylene copolymer, polyethylene (low density), polyethylene (high density), and polypropylene.

[0297] The organic solid lubricant particles are preferably a compound represented by the following general formula (SC1) or general formula (SC2).

[0298] General formula (SCI) (R) -X L X — (R)

SCI p2 SCI 6 SC2 SC2 q2

General formula (SC2) (R COO M ^{+ z}

SCI z

In the formula, each R R represents a C 6 60 substituted or unsubstituted alkyl group,

SCI SC2

A kenyl group, an aralkyl group or an aryl group, and when p2 or q2 is 2 or more, R and R may be the same or different. X and X each contain a nitrogen atom

SCI SC2 SCI SC2

Indicates a divalent linking group. L is a substituted or unsubstituted p2 + q2 valent alkyl group, alkyl-

6

R group, aralkyl group or aryl group. M represents a Z-valent metal ion.

[0299] In the compound represented by the above general formula (SC1) or (SC2), the total number of carbon atoms is not particularly limited, but generally 20 or more is preferable, and 30 or more is more preferable. Definition of R and R

Examples of the substituent that the alkyl group, alkenyl group, aralkyl group or aryl group in SCI SC2 may have include a halogen atom, a hydroxyl group, a cyan group, an alkoxy group, an aryloxy group, an alkylthio group, Aryloyl group, alkoxycarbol group, aryloxycarbol group, amino group, acylamino group, sulfo-lumino group, ureido group, force rubermoyl group, sulfamoyl group, isacyl group, sulfol group, sulfiel group, aryl group And an alkyl group. These groups may further have a substituent, and preferred substituents include a halogen atom, a hydroxyl group, an alkoxy group, an alkylthio group, an alkoxycarbo group, an acylamine group, a sulfo-amino group, an acyl group, and the like. And an alkyl group. As the halogen atom, a fluorine atom and a chlorine atom are preferable.

[0300] The alkyl component in the alkoxy group, the alkylthio group, and the alkoxycarbonyl group is the same as the alkyl group of R 1 described later. The amino group of the acylamino group and sulfo-lumino group

SC2

The group may be an N-substituted amino group, and the substituent is preferably an alkyl group. The groups bonded to the acyl group, the carbo group of the acyl group, and the sulfo group of the sulfoamino group are an alkyl group and an aryl group, and the above alkyl groups are preferable.

[0301] R 1 and R 2 have 6 to 60 carbon atoms, preferably 6 to 40 carbon atoms, more preferably 10 carbon atoms.

SCI SC2

-30 substituted or unsubstituted alkyl groups, alkenyl groups, aralkyl groups, or aralkyl groups, and these alkyl groups, alkenyl groups, and aralkyl groups may be linear, branched, or containing a cyclic structure. A mixture of these may be used. Preferred and R examples

RSCl SC2 includes octyl, t-octyl, dodecyl, tetradecyl, hexadecyl, 2-hexyldecyl, octadecyl, C H (n is 20 to 60), eicosyl, docosal, melicyl.

n 2n- 1

, Octenyl, myristol, oleyl, erucyl, phenyl, naphthyl, benzyl, naphthyl, dipentyl, cyclohexyl, and groups having these substituents. [0302] Divalent linking groups X and X containing a nitrogen atom are preferably CON (R) —, —N (R

SCI SC2 3 4

) CON (R) —, — N (R) COO. Where R to R are each a hydrogen atom or a substitution

5 6 3 6

Indicates a group.

[0303] L represents a substituted or unsubstituted p + q-valent alkyl group, alkenyl group, aralkyl group,

6

Indicates the reel group. Although carbon number of these hydrocarbon groups is not specifically limited, Preferably it is 1-60, More preferably, it is 1-40, More preferably, it is 10-40. p2 + q2 valent hydrocarbon in p2 + q2 valent hydrocarbon group means that p2 + q2 hydrogen atoms in the hydrocarbon are removed and p 2 X — groups and q2 X groups are bonded Indicates to do. p2 and q2 are integers from 0 to 6

SCI SC2

I≤p2 + q2≤6, preferably I≤p2 + q2≤4. It is also preferred that both p2 and q2 forces ^ are 1.

[0304] The compound represented by the general formula (SC1) may be a synthetic product or a natural product. Even if it is a natural product or a synthetic product, synthetic compounds made from higher fatty acids and alcohols of natural products, including those with different carbon numbers, straight-chain and branched compounds, and the ability to form a mixture of these compounds It's okay to use a mixture! / ヽ. From the viewpoint of the quality stability of the composition, a synthetic product is preferred.

[0305] Specific examples of the preferred compound represented by the general formula (SC) are shown below, but the present invention is not limited thereto.

[0306] Lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, hydroxy stearic acid amide, oleic acid amide, ergic acid amide, ricinoleic acid amide, N lauryl lauric acid amide, N-palmityl palmitic acid amide , N-stearyl stearic acid amide, N oleyloleic acid amide, N-stearyl oleic acid amide, N oleyl stearic acid amide, N-stearyl oleic acid amide, N oleyl palmitic acid amide, N-stearyl monohydroxystearic acid Amide, N-oleyl hydroxystearic acid amide, methylol stearic acid amide, methylol behenic acid amide, methylene bis stearic acid amide, methylene bis lauric acid amide, methylene bis hydroxy stearic acid amide, ethylene Strength prillic acid amide, ethylene bis strength purinic acid amide, ethylene bislauric acid amide, ethylene bisstearic acid amide, ethylene bisisostearic acid amide, ethylene bishydroxystearic acid amide, ethylene bisbehenic acid amide, hexamethylene Bistearic acid Amide, Hexamethylenebisbehenamide, Hexamethylenebishydroxystearic acid amide, Butylene bishydroxystearic acid amide, N, N '-Distearyl adipic acid amide, N, N'-Distearyl sebacic acid amide, Methylene bisoleic acid amide, ethylene bis-oleic acid amide, ethylene bis-ergic acid amide, hexamethylene bis-oleic acid amide, N, N '—dioleyl adipic acid amide, N, N ′ —dioleyl sebacin Acid amide, m—xylylene stearamide, N, N ′ —distearylisophthalic acid amide, ethanolamine distearate, N—butynole N ′ —stearinoreurea, N—phenole N′—stearyl urea , N-stearinore N'-stearyl urea, xylylene bis-stearyl urea, toluylene bis-steer Rilurea, hexamethylene bisstearyl urea, diphenylmethane bisstearyl urea.

[0307] The organic solid lubricant is preferably used in a state of being dispersed in advance in the coating solution. As the name suggests, organic solid lubricants are slippery on the surface, so the affinity of water and organic solvents is often not sufficiently high. Aggregation or sedimentation may occur. Aggregation or sedimentation in the coating solution is undesirable because it causes coating failure when processed into a film. Methods for improving the stability of the dispersion include a method of modifying the surface and using an electrostatic effect, and a method of using the effect of steric hindrance using a surface adsorbing layer by a polymer dispersant. The former is a general dispersion stabilization method. However, the use of the photothermographic material is likely to affect the other performance of the surface modifier itself, and it is effective for both aqueous and non-aqueous methods. The latter method, which is easy to express, is preferred.

[0308] As the polymer dispersant, a binder used in the photosensitive material can be used. Specifically, polybutyl butyral, polyvinyl acetal, poly vinyleno cornole, senorelose acetate butyrate, senorelose acetate propionate and the like can be used.

[0309] The amount of the polymer dispersant is preferably used in the range of 1 to 200% by mass with respect to the organic solid lubricant particles to be dispersed. The dispersion method is not particularly limited, but a resolver set, an ultrasonic method, a pressure method, or the like can be used, and it is preferable to perform the dispersion treatment with a dispersion device with a cooling device so as not to generate heat. [0310] The average particle size of the organic solid lubricant particles refers to the average particle size after dispersion by the following method. In order to obtain the average particle diameter referred to in the present invention, a dispersion liquid containing lubricant particles is diluted, dropped onto a grid with a strong support film, and dried, and then a transmission electron microscope (manufactured by Nippon Denshi Co., Ltd.) is used. : 2000FX type, etc.), directly after taking a photo at 5000x magnification, the scanner captures the negative as a digital image, and using an appropriate image processing software, each particle size (equivalent circle diameter) is 300 The average particle size can be obtained from the arithmetic average measured as described above.

[0311] In the light-sensitive material of the present invention, at least one layer on the support contains the compound represented by the general formula (SC), and a nonionic fluorine-containing surfactant and an anionic fluorine-containing interface. U, which preferably contains an activator.

[0312] The nonionic fluorine-containing surfactant that can be used is not particularly limited, but a compound represented by the following formula (AIF) is preferred.

[0313] General formula (AIF) Rf — (AO) — Rf

1 n3 2

Where Rf

1 and Rf

2 represents a fluorine-containing aliphatic group, which may be the same or different. AO represents a divalent group having at least one alkyleneoxy group, and n3 represents an integer of 1 to 30

[0314] The fluorine-containing aliphatic group represented by Rf and Rf includes linear, branched and cyclic groups, or

1 2

An aliphatic group composed of these combinations, for example, an alkylcycloaliphatic group can be mentioned. Preferred fluorine-containing aliphatic groups include fluoroalkyl groups having 1 to 20 carbon atoms (—C F, 1 C F, etc.), sulfofluoroalkyl groups (C F SO—, C F SO—, etc.), C

4 9 8 17 7 15 3 8 17 3 n

F SO N (R) R single group (R is a hydrogen atom, alkyl group having 1 to 20 carbon atoms,

2n + l 2 1 2 1

Coxyl group, alkyl carboxyl group or aryl group, and R each have 1 to 20 carbon atoms.

2

Represents an alkylene group or an alkylene carbonyl group, and n represents an integer of 1 to 20. C F SO

7 15 2

N (C H) CH

2 5 2, C F SO N (CH COOH) CH CH CH—etc.)

8 17 2 2 2 2 2

You may have a substituent.

[0315] AO is a group having an alkyleneoxy group such as ethyleneoxy, propyleneoxy, i-propyleneoxy and the like, and may have a substituent such as an amino group at the terminal. n is preferably an integer of 5 to 15. Examples of nonionic fluorine-containing surfactants represented by the general formula (AIF) are CF (CH CH O) CF, CF (CH CH O) CF, CF CH CH (OH) CH (CH CH O) CH CH (OH) CH CF, CF (CH CH O) CF, CF (CH C

2 2 15 2 2 7 15 7 15 2 2 10 7 15 12 25 2

H O) C F, C F CH CH (OH) CH (CH CH O) CH CH (OH) CH C F, C

2 15 12 25 8 17 2 2 2 2 20 2 2 8 17

F (CH CH O) C F, C F (CH CH O) C F, C F SO N (C H) CH (CH

8 17 2 2 18 8 17 8 17 2 2 20 8 17 7 15 2 2 5 2 2

CH O) CH N (CH) SO C F, C F O (CH CH O) C F and the like,

2 22 2 3 2 7 15 9 17 2 2 22 9 17

The present invention is not limited to these.

[0316] Further, as the ionic fluorine-containing surfactant (FA) that can be used in the present invention, there is no particular limitation, but specific compounds are shown below, but the present invention is not limited thereto.

[0317] [Chemical 37]

FA-1

CI

HOOC— (CFJ-CF ^ -COJH

FA-2

CI

CI (CF ₂ -CF> ₃ CF ₂ C0 ₂

FA—3

FA-4

CF ₃

CF ₃ (CF ₂ ¾-CF- (CH ₂ ) — C0 ₂ Na

FA—a

H (CF ₂ -CF ₂ ) ₄ CH ₂ -O-SO _z — <CO _z H

FA—6

CH ₃

CF ₃ (CF ₂ -CO-N (CH ₂ ) ^ ~ C0 ₂ H

FA

FA -8

CF ₃

CF ₃ -C C-CHF-CF,

C ₂ F ₃ SOjNa [0318] [Chemical 38]

FA—9

C ₃ H ₇

I

CHsCOOCHsCHaNSO H,

Na0 ₃ S-CHCOOCH ₂ CH ₂ NSO ₂ C ₈ H ₁₇

S0 ₃ Na is 4th or 5th or a mixture of them)

FA -11

O

H— (CF ₂ > ₄ — CH ₂ —

OH

FA 12

O

H-(CF ₂ ) ₃ -p-ONa

ONa

FA—13

FA—14

C ₂ H ₅

C ₆ H ₁₃ CONCH ₂ COONa

FA— 15 C ₃ H ₇

I

CF _s (CF ₂ ) ₇ S0 ₂ -N-CH ₂ -S0 ₃ Na

FA— 16 C ₃ H ₇

I

C _a H ₁₇ S0 ₂ -N- {CH ₂ CH ₂ 0) ₄ (CH ₂ ) 4S0 ₃ Na

[0319] [Chemical 39] FA—17

C ₂ H ₅

CF ₃ (CF ₂ ) ₇ S0 ₂ -N-CH ₂ -COONa FA- 18

C3H7

I

CF ₃ (CF ₂ ) ₇ S0 ₂ — N— CH ₂ — COOK

FA—19

C ₂ H ₆

C _a H ₁₇ CONCH ₂ CH ₂ S0 ₃ Na

(One S0 ₃ K is o-, m- or p-position, or a mixture of them>

FA— 21 C ₂ H ₅

CF ₃ (CF ₂ ) ₇ S0 ₂ -N-{CH ₂ ) _s -COOK FA -22

CF ₃ <CF ₂ >"— CH ₂ — 0— SQ ₃ Na

FA -23

CF ₃ (CF ₂ ) ₆ -COO (CH ₂ ) ₃ -SO3K

FA -24

H <CF ₂ ) ₄ — CH ₂ _ O— (CH ₂ } _ S 0 ₃ Na

FA-25

CH ₂ COOCH ₂ (CF ₂ ) ₄ H Na0 ₃ S— CHCOOCH ₂ (CF ₂ ) ₄ H

40]

3ε -Vd

^E (BNO) dO ^z HO ^z HOO— ^ O d ⁶ 0

eiMOOO— (— O ^il d ^s O

οε-vd

eN ^E OS-. "d

8Z-VJ

■ j ¹

ed0

'dO- ^ OOOO-HD-^' O

BN ^s OS

.Zl90 / .00Zdf / X3d Z6

FA -36

CH ₃ — CONCH ₂ CH ₂ COOK

FA—37

C ₉ F ₁₇ 0— — S0 ₂ NCH ₂ CH ₂ COOH

FA -38

C ₉ F ₁₇ OCH _z CH ₂ S0 ₃ Na

FA-39

OCH ₂ CH ₂ CH ₂ CH ₂ OP (ONa) ₂

FA -42

HCF ₂ (CF ₂ ) _B OCH ₂ CH ₂ CH ₂ SO _a Na 42]

FA -43

HCF ₂ (CF ₂ ) ₉ 0— ^ V- (OCH ₂ CH ₂ ) _{1 ()} 0- (CH ₂ ) 3S03Na

FA -44

FA— 45

C ₃ H _T

C ₈ F ₁₇ SOjNCH ₂ COONa

FA 46

C ₉ F ₁₇ 0— — COONa

FA -47

. S0 ₃ Na

FA—48

C3H7

0 F ^ ₇ S0 ₃ N- (CH ₂ CH ₂ 0) ₃ 《CH ₂ ) ₄ S0 ₃ Wa 3]

FA— 49 FA-50

C ₇ F ₁₅ COOH H-fCF ₂ — CHjCOOIMH ₄

FA -55 FA -56

CH ₃ H- (CF ₂ ) j-CH ₂ OOC-CH ₂

C ₇ F ₁₅ CON-CH ₂ CH ₂ S0 ₃ Na

H ~ fCF ₂ ) | ~ CH ₂ OOC— CH— S0 ₃ Na

FA—57

H to CF ₂ CH ₂ 0 to CH ₂ CH ₂ 0 OC-CH ₂

H ~ cF CH ₂ 0 ~ (CH ₂ CH ₂ 0 ^ ~ OC-CH-CH ₂ S0 ₃ p: Average 3

FA -58

C ₃ H ₇

C ₈ F ₁₇ SO ₂ N- CH ₂ CH ₂ O- (CH _i ) 5-S0 ₃ Na p: Average 4

FA— 59

p: Average 7

FA -60

Cio ^ iC ^ CHzO-fCHjC ^ O- ^ p-fCHj ^ j-SOaNa p: Average 6

FA ~ 61 -62

C ₃ H ₇ o C ₃ H ₇ O

C _a F ₁₇ SO _z N -CH ₂ CH ₂ 0 1 P— ONa C ₈ F ₁₇ S0 ₂ N— fCH ₂ CH ₂ 0½ -P-ONa

ONa

p: Average 5

FA -63

C, H ₇

C ₈ l = ₁₇ S0 ₂ N— CH ₂ CH ₂ OS0 ₃ Na 44]

FA -64

yCOONa

C ₃ F _{1 7} S0 ₂ IM

COONa

FA -67

C ₆ H ₁₃ 0 -OC-CH ₂

C ₈ F ₁₇ CH ₂ CH ₂ OOC-CH-S0 ₃ Na

FA -68

C ₃ H ₇

C ₈ F ₁₇ SOjN— fCH ₂ CHCH ₂ o) j- CH ₂ ) j-S03Na

OH

FA -69

The amount of each fluorine-containing surfactant used is generally from 0.01 to lm ² of photosensitive material: Lg is preferred, and 10 to 500 mg is preferred! / ヽ. More preferably, it is 50 to 300 mg.

In addition to the above, fluorine-containing surfactants include ionic fluorine-based surfactants described in JP-A-60-244945, JP-A-63-306437, and JP-A-1-24245; Fluorosurfactants used in combination with cation cation as described in 197, 068, 5-204115, etc. can be used.

The addition layer of the fluorine-containing surfactant may be any layer without particular limitation, but is preferably contained in the outermost layer. [0326] (Dye, pigment)

In the photothermographic material of the present invention, a filter layer is formed on the same side as or opposite to the photosensitive layer in order to control the amount of light transmitted through the photosensitive layer or the wavelength distribution. It is preferable to contain a dye or a pigment. As the dye used, known compounds that absorb light in various wavelength regions can be used depending on the color sensitivity of the photosensitive material.

[0327] For example, when the photothermographic material of the present invention is used as an image recording material by infrared light, a squarylium dye having a thiopyrylium nucleus as disclosed in JP-A-2001-83655 (this specification) A thiopyrylium squarium dye), a squarylium dye having a pyrylium nucleus (referred to herein as a pyrylium squarylium dye), Alternatively, it is preferable to use a pyrylium crocoum dye.

[0328] A compound having a squarylium nucleus is a compound having 1-cyclobutene-2-hydroxy-4one in the molecular structure, and a compound having a croconium nucleus is 1-cyclopentene-2-hydroxylone in the molecular structure. It is a compound having 4, 5 dione. Here, the hydroxyl group may be dissociated. Hereinafter, in the present specification, these pigments are collectively referred to as squarylium dyes for convenience. As the dye, a compound described in JP-A-8-201959 is also preferable.

[0329] (Support)

Support materials used for photothermographic materials include various polymer materials, glass, wool cloth, cotton cloth, paper, metal (aluminum, etc.), etc. What can be processed into a certain sheet or roll is suitable. Accordingly, the support in the photothermographic material of the present invention includes cellulose acetate film, polyester film, polyethylene terephthalate (PET) film, polyethylene naphthalate (PEN) film, polyamide film, polyimide film, cellulose triacetate film (TAC). ) Or a plastic film such as a polycarbonate (PC) film is preferred, and a biaxially stretched PET film is particularly preferred. The thickness of the support is about 50 to 300 μm, preferably 70 to 180 μm. In order to improve the chargeability, a metal oxide and a conductive compound such as z or a conductive polymer can be included in the constituent layers. These may be contained in any layer, but are preferably contained in the backing layer or the surface protective layer on the photosensitive layer side, the undercoat layer, and the like. The conductive compounds described in columns 14 to 20 of US Pat. No. 5,244,773 are preferably used.

[0330] In particular, in the present invention, it is preferable that the surface protective layer on the backing layer side contains a conductive metal oxide. Here, the conductive metal oxide is a crystalline metal oxide particle that contains oxygen defects and a small amount of foreign atoms that form donors with respect to the metal oxide used. Are generally preferred because of their high electrical conductivity, and the latter is particularly preferred because the latter does not add fog to the silver halide emulsion. Examples of metal oxides include ZnO, TiO, SnO, AlO, InO, SiO, MgO, BaO, MoO, VO, etc.

2 2 2 3 2 3 2 3 2 5

In particular, ZnO, TiO and SnO are preferred. Examples that include heteroatoms

twenty two

For example, Al, In, etc. are added to ZnO, Sb, Nb, P, halogen elements are added to SnO

2

Addition of elements, etc., and addition of Nb, Ta, etc. to TiO are effective. These heterogeneous fields

2

The addition amount of the child is preferably in the range of 0.01 to 30 mole ^_0/0, preferably especially if 0.1 to 10 mole ^_0/0. Furthermore, a silicon compound may be added during the production of fine particles in order to improve fine particle dispersibility and transparency.

[0331] The metal oxide fine particles used in the present invention have electrical conductivity, and the volume resistivity thereof is 10 ⁷ Ω'cm or less, particularly 10 ⁵ Ω'cm or less. These acid compounds are described in JP-A Nos. 56-143431, 56-120519, 58-62647 and the like. Furthermore, using a conductive material in which the above metal oxide is attached to other crystalline metal oxide particles or fibrous materials (such as titanium oxide) as described in JP-B-59-6235. Also good.

[0332] The particle size that can be used is preferably 1 μm or less, but if it is 0.5 m or less, the stability after dispersion is good and it is easy to use. In order to make the light scattering property as small as possible, it is very preferable to use conductive particles of less than 0. This makes it possible to form a transparent photosensitive material. When the conductive metal oxide is needle-like or fibrous, the length is preferably 30 / zm or less and the diameter is preferably 1 μm or less, and particularly preferably the length is 10 μm or less and the diameter is 0 μm. It is 3 μm or less, and the length Z diameter ratio is 3 or more. SnO is commercially available from Ishihara Sangyo Co., Ltd.

2

SNS10M, SN-100P, SN-100D, FSS10M, etc. are used! / I can do it. [0333] (Layer structure)

The photothermographic material of the present invention has a photosensitive layer which is at least one image forming layer on a support. Although only the photosensitive layer may be formed on the support, it is preferable to form at least one non-image forming layer on the photosensitive layer. For example, it is preferable that a protective layer is provided on the photosensitive layer for the purpose of protecting the photosensitive layer. On the opposite side of the support, a “clump” is formed between the photosensitive materials or in the photosensitive material roll. In order to prevent “sticking”, a knock coat layer is provided.

[0334] As a binder used in these protective layers and backcoat layers, a polymer having a glass transition point (Tg) higher than that of the photosensitive layer and less likely to be scratched or deformed, such as cellulose acetate, cellulose acetate butyrate, and cellulose acetate. Polymer power such as propionate The medium power of the binder is selected.

[0335] Note that two or more photosensitive layers may be provided on one side of the support or one or more layers on both sides of the support for gradation adjustment and the like.

[0336] (Application of constituent layers)

The photothermographic material is preferably formed by preparing a coating solution in which the above-described constituent materials are dissolved or dispersed in a solvent, applying a plurality of coating solutions simultaneously, and then performing a heat treatment. Here, “multiple simultaneous multi-layer coating” means that the coating solution for each component layer (photosensitive layer, protective layer, etc.) is prepared, and when this is applied to the support, the coating and drying are repeated for each layer individually. This means that the constituent layers are formed in such a state that the multilayer coating is simultaneously performed and the drying process can be performed simultaneously. That is, the upper layer is provided before the remaining amount of all the solvents in the lower layer reaches 70% by mass or less (more preferably 90% by mass or less).

[0337] There are no particular restrictions on the method of simultaneously applying multiple layers of each constituent layer, for example, bar coater method, curtain coating method, dipping method, air knife method, hopper coating method, reverse roll coating method, gravure coating method, etast A known method such as a coating method can be used. Of these various methods, the slide coating method and the etatrusion coating method are more preferable. These coating methods are the same in the case of coating with the undercoat layer when providing the force back layer described for the side having the photosensitive layer. JP-A-2000-15173 has a detailed description on the simultaneous multilayer coating method in the photothermographic material. The

[0338] The silver coating amount is preferably selected in accordance with the purpose of the light-sensitive material, but is preferably 0.8 to 1.5 g / m ² for the purpose of medical images. G 1.0 to 1.3 g / m ² is more preferred. Among the coated silver amounts, those derived from halogenated silver preferably occupy 2-18% of the total silver amount, and more preferably 5-15%. Further, the coating density of halogen silver particles of 0.01 m or more (equivalent particle diameter equivalent to a sphere) is preferably 1 × 10 ¹⁴ to 1 × 10 ¹⁸ particles / m ² . Furthermore, 1 × 10 ¹⁵ to 1 × 10 ¹⁷ / m ² is preferable.

[0339] Further, the coated weight of light-insensitive long-chain aliphatic carboxylic acid silver Said, Harogeni匕銀one particle per 1 X 10- ¹⁷ to 1 of 0. 01 mu m or more (a sphere equivalent grain diameter) X 10- ¹⁴ g is preferred instrument ^{^{1 X 10- 16 ~1 X 10- 15}} g is more preferred.

[0340] When applied under the conditions within the above ranges, the maximum optical density of the silver image per certain amount of applied silver, that is, the silver coating amount (covering power), the color tone of the silver image, etc. I also like power and get results.

[0341] The photothermographic material of the present invention contains a solvent in the range of 5 to 1, OOOmgZm ² during development! /, I prefer to be. It is more preferable to be adjusted so that 10~ 150mg / m ^2! /. As a result, the photothermographic material has high sensitivity, low capri and high maximum density. Examples of the solvent include those described in JP-A-2001-264930, paragraph “0030”, but are not limited thereto. These solvents can be used alone or in combination of several kinds. The content of the solvent in the photosensitive material can be adjusted by changing conditions such as temperature conditions in the drying process after the coating process. The content of the solvent can be measured by gas chromatography under conditions suitable for detecting the contained solvent.

[0342] (Heat development)

The photothermographic material of the present invention is characterized in that after imagewise exposure, the photothermographic material is processed by a heat developing machine that forms an image by heating at a desired development temperature. The heat development temperature is preferably in the range of 110 to 150 ° C, more preferably in the range of 115 to 135 ° C. If the heating temperature is less than 80 ° C, sufficient image density cannot be obtained in a short time, and if the heating temperature is high (particularly 200 ° C or more), transfer to a roller due to melting of the binder, transportability, developing machine, etc. Adversely affect . By heating, a silver image is generated by a redox reaction between an aliphatic carboxylic acid silver salt (which functions as an oxidizing agent) and a reducing agent. This reaction process proceeds with no external supply of treatment liquid such as water! / ヽ.

[0343] The heating means may be any means such as contact heating with a heating drum or a heating plate, non-contact heating such as radiation, but contact heating with a heating plate is preferred. The contact heating surface may be either the image forming layer (photosensitive layer) side or the non-image forming layer (non-photosensitive layer) side. The non-image forming layer (photosensitive layer) side is the contact heating surface for stability to the processing environment. I prefer to be there. It is preferable that the developing unit is configured by combining a plurality of zones and a plurality of means that are independently temperature controlled, and further includes at least one heat retention zone that maintains a specific developing temperature. Preferably it is. Therefore, in the heat development apparatus that can be preferably used in the present invention, the heat development process can employ a separate structure for the temperature raising portion and the heat retaining portion, and in the temperature raising portion, heating means such as a heating member can be used. By maintaining close contact with the sheet film and suppressing the occurrence of density unevenness, the heat retaining part uses an optimum heating method that is different between the temperature rising part and the heat retaining part, which does not require such close contact, It is possible to achieve a configuration that allows rapid processing of the thermal development process, downsizing of the apparatus, and cost reduction while maintaining high image quality without density unevenness.

[0344] In the heat development apparatus, the temperature raising unit heats the sheet film while pressing the sheet film against a plate heater by a counter roller, and the heat retaining unit is interposed between guides having at least one heater. The sheet film can be heated in the formed slit. In the temperature raising part, the sheet heater is pressed against the plate heater by the opposing roller and brought into contact with the plate heater, so that the plate heater and the sheet film can be brought into close contact with each other. Therefore, it is only necessary to transport while keeping the temperature between the slits (heat insulation), so there is no need for drive parts for the transport system, and the size of the device can be reduced and the cost can be reduced without requiring much accuracy of the slit dimensions. Become. Example

[0345] Hereinafter, the present invention will be described in detail with reference to examples, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, “parts” in the examples represents “parts by mass” and “%” represents “% by mass”.

[0346] (Preparation of underdrawn support) Corona discharge treatment was applied to both sides of a biaxially stretched PET film with a blue dye concentration of 0.113 under the condition of 1 OWZm ² min, and the coating solution for the undercoat layer on the back side with the following composition was dried on one side. After coating to a thickness of 0.06 / zm and drying at 140 ° C, the coating solution for the knock surface side undercoat with the following composition was applied to a dry film thickness of 0.2 m. Dried at 140 ° C. On the other side, a coating solution for the undercoat layer on the image forming surface side having the following composition is applied so as to have a dry film thickness of 0.25 m, and then the undercoat layer on the image forming surface side having the following composition. The coating solution was applied to a dry film thickness of 0.06 / zm and then dried at 140 ° C. These were heat-treated at 140 ° C. for 2 minutes to obtain an undercoated support.

[0347] Surfactant for undercoat layer:

[2, 4— (C H)] — C H— (CH CH O) SO Na

9 19 6 3 2 2 12 3

(Back surface side undercoat lower layer coating solution)

Styrene Z Glycidyl metatalylate Copolymer polymer latex of Z-butyl atylate (20Z20Z40) (solid content 30%) 16. Og

Styrene Z-Butyl Atylate Copolymer latex of Z-hydroxymethyl metatalylate (25Z45Z30) (solid content 30%) 4. Og

Tin oxide sol (solid content 10%, synthesized by the method described in JP-A-10-059720) 91g Surfactant SA-1 for subbing layer 0.5g

Distilled water was added to make 1,000 ml to make the coating solution.

[0348] (Back surface side undercoat upper layer coating solution)

Modified water-based polyester for knock layer * (solid content 18%) 215.0 g Surfactant for undercoat layer 0.4 g

True spherical silica matting agent (Seahoster KE-P50: manufactured by Nippon Shokubai Co., Ltd.) Distilled water was added to 0.3 g or more to make 1,000 ml to obtain a coating solution.

In a polymerization reactor, dimethyl terephthalate 35.4 parts, dimethyl isophthalate 33.63 parts, 5-sulfo-isophthalic acid dimethyl sodium salt 17.92 parts, ethylene glycol 62 parts, calcium acetate monohydrate 0.065 parts Then, 0.022 part of manganese acetate tetrahydrate was added and transesterification was carried out while distilling methanol at 170-220 ° C under a nitrogen stream. After that, 0.04 part of trimethyl phosphate, 0.04 part of antimony trioxide as a polycondensation catalyst and 6.8 parts of 1,4-cyclohexanedicarboxylic acid were added, and the reaction temperature of 220-235 ° C was almost theoretical. An amount of water was distilled off and esterification was conducted. Thereafter, the reaction system was further depressurized and heated for about 1 hour, and finally subjected to polycondensation at 280 ° C. and 133 Pa or less for about 1 hour to obtain a modified aqueous polyester precursor. The intrinsic viscosity of the precursor was 0.33.

[0350] 850 ml of pure water was placed in a 2 L three-necked flask equipped with a stirring blade, a reflux condenser, and a thermometer, and 150 g of the precursor was gradually added while rotating the stirring blade. The mixture was stirred at room temperature for 30 minutes, then heated to an internal temperature of 98 ° C over 1.5 hours, and heated at this temperature for 3 hours * dissolved. After completion of the heating, the mixture was cooled to room temperature over 1 hour and allowed to stand overnight to prepare a precursor solution having a solid concentration of 15%.

[0351] Put 1900 ml of the above precursor solution in a 3 L four-necked flask equipped with a stirring blade, reflux condenser, thermometer, and dropping funnel, and heat the internal temperature to 80 ° C while rotating the stirring blade. did. To this, 6.52 ml of a 24% aqueous solution of ammonium peroxide was added, and a monomer mixture (28.5 g of glycidyl methacrylate, 21.4 g of ethyl acrylate, 21.4 g of methyl methacrylate) was added. The solution was added dropwise over a period of 3 minutes, and the reaction was continued for another 3 hours. Thereafter, the solution was cooled to 30 ° C. or lower and filtered to prepare a solution of a modified aqueous polyester for a back layer having a solid concentration of 18%.

[0352] (Image forming surface side undercoat coating solution)

Copolymer latex of styrene Z-acetoxetoxyl metatalylate Z glycidyl metatalylate Z butyl acrylate (40Z40Z20Z0.5) (solid content 30%)

70g

Surfactant for undercoat layer 0.3g

Distilled water was added to make 1,000 ml to make the coating solution.

(Image forming surface side undercoat upper layer coating solution)

Modified water-based polyester for image forming surface * (Solid content 18%) 80. Og Surfactant for subbing layer 0.4 g

True spherical silica matting agent (Seahoster KE-P50: mentioned above) Distilled water was added to 0.3 g or more to make 1,000 ml, and a coating solution having a solid content concentration of 0.5% was obtained.

<Synthesis of modified aqueous polyester for image forming surface *> 1800 ml of the modified aqueous polyester precursor solution, 31 g of the monomer mixture, 3 lg of acetocetoxy chinenoremethacrylate, 6 lg of glycidinomethacrylate, 7.6 g of butyrate Except that, a solution of the modified aqueous polyester for image forming surface having a solid content concentration of 18% was prepared in the same manner as the modified aqueous polyester for knock layer.

(Preparation of silver halide emulsion)

(Solution A)

Phthalated gelatin (phthalated modification rate 95%) 66. 2g Surfactant AO-1 (10% methanol aqueous solution) 10ml Potassium bromide 32g

Finish to 5429 ml with water.

AO-: HO— (CH CH O) (CH (CH) CH O) (CH CH O) H (m + n = 5 to 7)

(Solution B)

0. 67molZL Silver nitrate aqueous solution 2635ml

(Solution.)

Potassium bromide 51. 55g

Potassium iodide 1. 47g

Finish to 660ml with water

(Solution.)

Potassium bromide 154.9 g

Potassium iodide 4.41 g

Potassium iron cyanide (0.5% solution) 15ml

Ha chloride iridium acid (酸) potassium (1% solution) 0.93ml

Finish to 1982ml with water

(Solution E)

0. 4molZL potassium bromide aqueous solution

(Solution F)

Potassium hydroxide 0.71g Finish to 20ml with water

(Solution G)

56% aqueous acetic acid 10. Oml

(Solution H)

Anhydrous sodium carbonate 1.16g

Finish to 107ml with water

Using the mixing stirrer shown in Japanese Patent Publication No. 58-58288, a 1/4 volume of solution B and a total volume of solution C were added to solution A at a temperature of 35 ° C, pAg 8.09 at the same time. It was added over a period of 4 minutes 4 ⁵ seconds by been nucleation. After 1 minute, the entire amount of Solution F was added. During this time, solution E was used appropriately for the adjustment of pAg. After 6 minutes, the amount of 3Z4 of solution B and the total amount of solution D were added over a period of 14 minutes and 15 seconds by a simultaneous mixing method at a temperature of 35 ° C. and a pAg of 8.09 μg. After stirring for 5 minutes, the temperature was lowered to 30 ° C., and the entire amount of Solution G was added to precipitate the silver halide emulsion. The supernatant was removed leaving 2000 ml of the sedimented portion, 10 liters of water was added, and after stirring, the halogenated silver emulsion was again settled. The remaining portion of 1500 ml was left, the supernatant was removed, 10 liters of water was further added, and after stirring, the silver halide emulsion was allowed to settle. After leaving 1500 ml of the sedimented portion and removing the supernatant, Solution H was added, the temperature was raised to 60 ° C, and the mixture was further stirred for 100 minutes. Finally, the pH was adjusted to 5.8, and water was added so that the final finish was 1150 g, to obtain a photosensitive halogen silver halide emulsion. This emulsion was monodisperse cubic silver iodobromide grains having an average grain size of 0.043 ^ m and a (100) plane ratio of 92%.

(Preparation of polymer for amphiphilic dispersion)

0. A 5-liter four-separable flask equipped with a dropping device, thermometer, nitrogen gas inlet tube, stirring device and reflux condenser, methyl ethyl ketone (MEK) 50 g, diacetone acrylamide 20 g, methoxypolyethylene glycol Charge 20g of monometatalylate (Nippon Yushi Co., Ltd .: Bremer PME-400), 20g of stearoxy polyethylene glycol monometatalylate (Blenmer PSE-400, Nihon Yushi Co., Ltd.) and 0.12g of lauryl peroxide. Heated to 80 ° C. Further, a solution obtained by dissolving 40 g of N-iso-propylacrylamide in 43 g of MEK was dropped into a separable flask over 2 hours. Thereafter, the temperature was raised over 1 hour, and when it was refluxed, 0.17 g of lauryl peroxide was dissolved in 33 g of MEK. The liquid was dropped into the flask over 2 hours and reacted at the same temperature for another 3 hours. Thereafter, a solution obtained by dissolving 0.33 g of methylhydroquinone in 107 g of MEK was added, and after cooling, a 30% polymer solution for amphiphilic dispersion was obtained. The molecular weight was about 120,000 in terms of polyethylene oxide equivalent mass average molecular weight by GPC (gel permeation chromatography). Subsequently, this polymer solution was dropped into a sufficient amount of water, and the supernatant was removed to take out a polymer solid.

[0356] (Preparation of amphiphilic dispersion of silver halide grains)

38 g of methanol was added to 7.5 g of the polymer solid content for amphiphilic dispersion and dissolved at 45 ° C. with stirring for 30 minutes. Thereto, 42 g of the silver halide emulsion adjusted to 45 ° C. was added dropwise over 2 minutes, and the mixture was further stirred for 30 minutes. After cooling this solution to 30 ° C, the solution left for 30 minutes is separated into two layers. The supernatant of the liquid was removed, and 500 g of MEK was added to the remaining liquid. After stirring well, distillation was performed under reduced pressure until the water content in the liquid was less than 5%. Finally, MEK was added so that a total amount of 157 g and 50 g of a 10% polybutyl petital M EK solution were added to obtain an amphiphilic dispersion of silver halide grains.

[0357] (Preparation of aliphatic carboxylate silver particles)

Aliphatic carboxylic acid (compositional molar ratio is behenic acid: arachidic acid: stearic acid = 85/1 1/4) 1,850 g and 90% of pure water adjusted to 5% concentration are stirred at 85 ° C. Then, 1036 ml of 5 molZL potassium hydroxide aqueous solution was added over 5 minutes and then reacted for 60 minutes to obtain an aliphatic potassium carboxylate aqueous solution. Then additional pure was added so that the concentration of the aqueous potassium aliphatic carboxylate solution was 5%. On the other hand, 38 and 300 g of a 5% silver nitrate aqueous solution were prepared and kept at 10 ° C. Aliphatic potassium carboxylate aqueous solution and silver nitrate power A pump capable of feeding at a constant flow rate was prepared, and a reaction device was prepared so that both solutions could react in a Y-shaped mixing device. Add the total amount of the previous aliphatic potassium carboxylate aqueous solution and silver nitrate aqueous solution to the mixing device over 4 minutes at a constant addition rate, and stock the liquid that came out from the lower part of the Y-shaped tube. did. During the addition, the stock tank was kept at 35 ° C. Thereafter, the solid content was separated by suction filtration, and the solid content was washed with water at 25 ° C. until the conductivity of the permeated water reached S / cm. The obtained dehydrated cake was dried at 50 ° C. using a fluidized bed to obtain a dried powder of aliphatic carboxylic acid silver salt particles. [0358] (Preparation of aliphatic carboxylic acid silver salt dispersion emulsion)

Polybulbutyral (Sekisui Chemical Co., Ltd .: ESREC B · BL-SHP) 41 g dissolved in MEK1, 239 g, VMA—GETZMANN resolver DISPERMAT CA— A preliminary dispersion was prepared by gradually adding 412 g of silver salt and mixing well. After adding all of the powdered aliphatic carboxylic acid silver salt, the mixture was stirred at 1,500 rpm for 15 minutes. This pre-dispersed liquid is a media-type disperser filled with 80% of the internal volume of 0.5 mm diameter Zirco Your Beads (made by Torayene Earth: Treceram) so that the residence time in the mill is 1.2 minutes. An aliphatic carboxylic acid silver salt dispersion emulsion was prepared by supplying to DISPERMAT SL-C125 EX type (VMA-GETZMANN) and dispersing at a mill peripheral speed of 9 mZs. The solid content concentration of the obtained aliphatic carboxylate silver salt dispersion emulsion was about 27%.

[0359] (Coating of image forming layer, surface protective layer, back layer)

An image forming layer and a slip layer are placed on the undercoat of the undercoated support on the image forming layer side so that the silver amount is 1.26 g / 0.06 gZm ² , and the wet weight is 23 gZm ² . A surface protective layer was applied in multiple layers. Subsequently, the back layer was applied on the opposite side of the image forming layer side undercoat so that the wet weight was 25 gZm ² . Each drying was performed at 60 ° C for 2 minutes. A photothermographic material was obtained by carrying out heat treatment at 79 ° C for 10 minutes while conveying the sample coated on both sides.

[0360] (Preparation of coating solution for image forming layer)

157 g of the silver halide grain amphiphilic dispersion was added to 1,692 g of the aliphatic carboxylic acid silver salt dispersion emulsion solution, and the mixture was kept at 18 ° C. with stirring, and bis (dimethylacetamido) dibromobromate. (1.1% methanol solution) 9.4 g was added and stirred for 1 hour. Subsequently, 11.3 g of calcium bromide (11% methanol solution) was added and stirred for 30 minutes. Further, an infrared sensitizing dye solution was added and stirred for 1 hour, and then the temperature was lowered to 13 ° C. and stirred for another 30 minutes. While keeping the temperature at 13 ° C., the polyvinyl butyral rosin powder shown in Table 1 was added and dissolved in the amount shown in Table 1 with respect to the total solid content in the image forming layer. After confirming dissolution, 37 g of tetrachlorophthalic acid (4.3% MEK solution) was added, and the following additives were added at intervals of 15 minutes, and stirring was continued to obtain an image forming layer coating solution. [0361] Phthalazine 12. 9g

DesmodurN3300 (Movey Corp .: polyfunctional aliphatic isocyanate)

Amounts shown in Tables 1 and 2

Leuco dye 1 1. 4g

Leuco dye 2 0. 6g

4-methylphthalic acid l lg

Anti-capri agent solution

Developer solution

Infrared sensitizing dye 1 200 mg, Infrared sensitizing dye 2 200 mg, 5-methyl-2-mercabutene imidazole 100 mg, 2 black mouth-benzoic acid 16 g, sensitizing dye solubilizer 1.5 g dissolved in MEK 135 g An infrared sensitizing dye solution was prepared.

Reducing agent 1-1: 160 g and dye- A: 500 mg was dissolved in MEK and finished to 800 g to obtain a developer solution.

16 g of tribromomethylsulfururidine was dissolved in MEK and finished to 180 g to obtain an antifoggant solution.

[0364] (Slip layer coating solution)

16.5 g of the image forming layer coating solution prepared above

MEK 1.5 g

Polymethylmetatalylate (Rohm and Haas, Paraloid A21) 25g (surface protective layer coating solution)

MEK 1056g

Cellulose acetate butyrate (Eastman Chemical Co., CAB171-15)

148g

Polymethylmetatalylate (Rohm and Haas, Paraloid A21) 6g Calcium stearate (Nippon Yushi Co., Ltd .: MC-2) 3g Crosslinking agent (CH = CH SOCH) CH (OH) 2.5g

2 2 2 2

Benzotriazonore 2g

Fluorosurfactant CF O (CHCHO) CF 5.

(Back layer coating solution)

MEK 1350g

Senorelose acetate propionate

(Eastman Chemical: CAP482-20) 155g

Dye A 0.71g

Dye B 1.7g

Fluorine-based acrylic copolymer (Daikin Kogyo Co., Ltd .: Optoflon FM450) 1.6 g Amorphous saturated copolyester (Toyobo Co., Ltd .: Byron 240P) 12 g True spherical cross-linking matting agent (Sekisui Chemical Co., Ltd .: MBX-8) 4. Og surfactant CF O (CHCHO) CF 7. lg

9 17 2 2 23 9

Surfactant LiO S (CF) SO Li

2 3 lg

[Chemical 45]

Infrared sensitizing dye 1

6]

Dye A

《Evaluation of fluctuation of sensitivity, capri concentration, maximum concentration by storage》

The photothermographic material sample prepared as described above was processed into half-cut size (34.5 cm x 43. Ocm), and then two samples of samples wrapped in the following packaging material in a 25 ° C 50% environment were prepared. . After storing at room temperature for 2 weeks, one bag was stored at 23 ° C ZlO days, and the other bag was stored at 55 ° CZlO days, and then the following evaluation was performed.

[0368] (Packaging materials)

PET10 μ m / PE12 μ mZ aluminum foil 9 μ m / Nyl5 μ mZ poly ethylene 50 comprising carbon 3% m (oxygen ^{permeability: 0. 05mlZatm * m 2 'day} (25 ° C), moisture permeability: 0. 0 01gZm ² 'day (40 ° C90% RH)) Barrier bag and paper tray are used. (Latm is 1. 01 3 X 10 ⁵ Pa.)

A laser imager equipped with a 786nm semiconductor laser with a maximum output of 50mW was exposed to heat and developed at 129 ° C for 8 seconds. The resulting image was evaluated with a densitometer. (Here, “heat development at the same time as exposure” means a sheet of photosensitive material made of photothermographic material that is partially exposed and developed on a part of the sheet that has already been exposed. But Means to be started. The distance between the exposed area and the developed area was 12 cm, and the linear velocity at this time was 30 mmZ seconds. The transport speed from the photosensitive material supply unit to the image exposure unit, the transport rate at the image exposure unit, and the transport rate at the thermal development unit were each 30 mmZ seconds. ) The exposure was performed in a stepped manner while reducing the exposure energy amount by logEO.05 for each step from the maximum output.

[0369] Measure the density of the formed image obtained as described above using a densitometer!ヽ, horizontal axis

A characteristic curve consisting of light intensity and vertical axis density was created. In the characteristic curve, the sensitivity is defined as the reciprocal of the exposure that gives a density 1.0 higher than the unexposed area, and the minimum density capri density (minimum density) and the maximum density were measured. Sensitivity was expressed as a relative value with the value of Sample 1 stored at 23 ° C for 10 days as 100.

[0370] [Table 1]

Desmodur For image forming layer For image forming layer For image forming layer

N3300 binder (1) binder (2)

(* 3)

Tg addition amount Tg addition amount total addition amount addition amount Degree of polymerization Risa! Three

('c) (* 1) (.c) (* 1) (* 2) (* 4)

500 62 40 ― ― ― 40 4.0%

500 62 22.75 2600 67 17.25 40 4.0%

500 62 22.75 2600 67 12.25 35 4.0%

500 76 22.75 2600 75 12.25 35 4.0%

500 76 22.75 2600 75 12.25 35 3.0%

500 76 17.75 2600 75 12.25 30 3.0%

500 76 12.75 2600 75 12.25 25 3.0%

500 76 10.75 2600 75 12.25 23 3.0%

500 76 17.75 800 73 12.25 30 3.0%

500 76 17.75 1000 73 12.25 30 3.0%

500 76 17.75 3000 73 12.25 30 3.0%

500 76 17.75 3500 72 12.25 30 3.0%

1200 75 40 ― ― ― 40 3.0%

1200 75 35 One ― ― 35 3.0%

1200 75 30 ― ― ― 30 3.0%

1200 75 25 ― ― ― 25 3.0%

1200 75 23 ― 23 3.0%

800 76 30 ― ― ― 30 3.0%

1000 76 30 ― ― ― 30 3.0%

3000 73 30 ― ― ― 30 3.0%

3500 72 30 ― One ― 30 3.0%

Performance 1 (* 5) Performance 2 (* 6)

No. Remarks

Force yellow density Senritsu density Sensitivity power yellow density Maximum density Sensitivity

1 0.17 3.3 100 0. 198 3.2 70 Comparison

2 0.168 3.21 96 0. 172 2.83 62 Comparison

3 0. 169 3.48 100 0.178 3.46 97 The present invention

4 0.167 3.45 99 0.171 3.4 91 The present invention

5 0.169 3.51 103 0.175 3.48 99 The present invention

6 0. 17 3.53 102 0.176 3.5 99 The present invention

7 0.172 3.53 103 0.178 3.51 100 The present invention

8 0.181 3.53 104 0.195 3.33 91 Comparison

9 0.182 3.47 107 0.203 3.25 85 Comparison

10 0.173 3.5 105 0.178 3.46 101 The present invention

11 0.168 3.54 100 0. 172 3.48 96 The present invention

12 0.165 3.33 89 0.168 2.98 63 Comparison

13 0. 166 3.35 90 0. 188 3. 14 68 Comparison

14 0.169 3.52 102 0.175 3.46 97 The present invention

15 0. 17 3.53 103 0.177 3.49 97 The present invention

16 0.172 3.5 103 0.179 3.5 99 The present invention

17 0.181 3.51 103 0.199 3.25 87 Comparison

18 0.179 3.45 105 0.201 3.13 66 Comparison

19 0.171 3.52 104 0. 179 3.44 95 The present invention

20 0.164 3.54 96 0. 167 3.5 93 The present invention

21 0.162 3.13 82 0. 164 2.54 55 Comparison * 1: Ratio to the total solid content in the image forming layer (mass%)

* 2: ratio of the binder total image forming layer to the total solid content in the image-forming layer (mass ^_0/0)

* 3: Made by MOI ^^: Polyfunctional aliphatic isocyanate

* 4: ratio to the binder total amount of the image forming layer (mass ^_0/0)

* 5: Performance of products stored at 23 ° C for 10 days (after storage for 2 weeks at room temperature)

* 6: Performance of 55 ° C / 10 曰 storage product (after storage for 2 weeks at room temperature)

As is clear from Tables 1 and 2, the photothermographic material of the present invention can greatly suppress capri (minimum density), capri rise during high-temperature storage without degrading sensitivity, and sensitivity reduction. Recognize.

Claims

The scope of the claims

[1] A photothermographic material having an image-forming layer containing a non-photosensitive aliphatic silver carboxylic acid salt particle, a photosensitive halogenated silver particle, a silver ion reducing agent, and a polymer binder on a support. The binder amount of the image forming layer is 25 to 35% by mass with respect to the total solid content contained in the image forming layer, and the binder has a polymerization degree of 1000 or more.

A photothermographic material comprising 000 or less of a polymer.

[2] The isocyanate layer compound is added to the image forming layer in an amount of more than 0% by mass and not more than 3.5% by mass with respect to the binder amount of the image forming layer. 2. The photothermographic material according to item 1.

[3] The photothermographic material according to [1] or [2], wherein the Tg of the noinder is 70 to 105 ° C.

[4] The photothermographic device according to any one of [1] to [3], wherein the image forming layer contains polyvinyl acetal resin as at least one binder. material.

[5] Any one of claims 1 to 4, wherein the non-photosensitive aliphatic carboxylic acid silver salt particles have a silver salt strength of a fatty acid having a behenic acid content of 70 to 99.99 mol%. 2. The photothermographic material according to claim 1.

[6] The photothermographic material according to any one of [1] to [5], wherein the silver ion reducing agent is represented by the following general formula (1).

[Chemical 1]

—General formula (1)

OH, OH

(CH ₂ ) _n (CH ₂ ) _m

A! A ₂

one two Three

Represents 3 to 8 branched alkyl groups. A and A are each independently a hydroxyl group, or reduction or deprotection. Represents a group capable of forming a hydroxyl group by being protected, and n and m represent an integer of 3 to 5. The total silver content of the non-photosensitive aliphatic carboxylic acid silver salt particles and the photosensitive halogenated silver particles is from 0.8 to 1.5 g / m ² . 6. The photothermographic material according to any one of items 6 above.