JPH05197068A - Heat developable photosensitive material - Google Patents

Abstract

PURPOSE:To obtain the heat-developable photosensitive material restrained from occurrence of fog in the case of storing it at a comparatively low temperature and improved in storage stability and coatability. CONSTITUTION:This heat-developable photosensitive material has on a support at least one kind of photosensitive layer containing a binder, photosensitive silver halide, and a dye donor releasing or forming a diffusible dye at the time of heat development, and also has at least one layer containing a F-containing cationic compound and a transition metal compound on the photosensitive layer side of the support, and it is preferred to add an anionic surfactant to this fluorocompound-containing layer and to add a nonionic surfactant to a layer formed on the photosensitive layer side of the support.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material, and more particularly to a photothermographic material having improved storage stability.

[0002]

BACKGROUND OF THE INVENTION A thermal development process in which a development process is performed by heating is known, and a process for obtaining a black and white image and a color image is known. Further, a so-called transfer type photothermographic material is also well known, which transfers an image obtained by heat development from the photographic material to the image receiving layer.

The photothermographic material usually has a binder, a photosensitive silver halide emulsion, a reducing agent, and, if necessary, a dye-donor substance, an organic silver salt and various other photographic additives on a support. is doing. Further, in the transfer type photothermographic material, the case where the above-mentioned photosensitive material has an image receiving layer capable of receiving silver or dye and the image receiving having an image receiving layer capable of receiving silver or dye are provided separately from the photosensitive material. May be used for.

In particular, when the photothermographic material is used as a photothermographic color photosensitive material, a method is used in which a dye image receiving material is used, and after the diffusible dye image is formed, the image dye is diffuse-transferred to the dye image receiving material. It is preferable from the viewpoint of obtaining a highly pure dye image.

Many methods and improved techniques for this method have been disclosed in the past.

The photothermographic material generally contains a reducing agent for a silver halide emulsion or an organic silver emulsion in the photosensitive material. These are generally reductive and are easily oxidatively decomposed during storage, or have a weak interaction with a silver halide emulsion, and have unfavorable adverse effects (for example, desensitization) during storage of the photothermographic material. , Dmin rise, Dma
x decrease, etc.) is given.

Therefore, a number of techniques have been proposed in the past for improving the storage stability of the photothermographic material. However, other techniques are not always adversely affected or the effect is insufficient. Not enough.

Japanese Unexamined Patent Publication (Kokai) No. 61-63839 discloses a technique of containing a transition metal ion to suppress fogging during storage. Specific examples of transition metal ions include Zn ²⁺ , N
i ²⁺ , Cd ²⁺ , Mn ²⁺ , V ³⁺ , Co ^{3+ and the} like are mentioned.
Examples of these salts include nitrates, sulfates, phosphates, acetates, borates, and benzoates.

As a result of further studies on these techniques, the present inventor found that the effect of preventing fogging by these transition metal ions is certainly 60 ° C. for 3 days, as described in the examples of the above publications. For relatively short-term storage at relatively high temperatures, such effects may be obtained, but at temperatures near room temperature for relatively long periods (for example, at 30 ° C, 1
It was found that the effect of preventing fogging of transition metal ions was insufficient when stored for about one month to half a year).

As a result of further study by the inventor of the present invention, the effect of reducing fogging by transition metal ions depends on the type of the surfactant contained in the photothermographic material when stored at such a relatively low temperature for a long period of time. I understood.

[0011]

SUMMARY OF THE INVENTION With respect to the above problems, an object of the present invention is to provide a photothermographic material having improved storability of the photothermographic material when stored at a relatively low temperature. A second object of the present invention is to provide a photothermographic material which suppresses the occurrence of fog, especially when stored at a relatively low temperature, and has improved coatability.

[0012]

The above object of the present invention is to provide, on a support, at least one photosensitive layer containing a binder, a photosensitive silver halide and a dye-donor substance which releases or forms a diffusible dye during heat development. The photothermographic material has a fluorine-containing cation compound and a transition metal compound in at least one layer on the side of the photosensitive layer with respect to the support.

It is a preferred embodiment of the present invention that the above-mentioned layer containing a fluorinated cation compound further contains an anionic surfactant and has a nonionic surfactant on the side of the photosensitive layer with respect to the support. ..

In the present invention, by incorporating a fluorine-containing cation compound and a transition metal compound in the photothermographic material, the occurrence of fogging when the photothermographic material is stored at a relatively low temperature for a long time is effectively prevented. However, when the fluorinated cation-based compound-containing layer further contains an anionic surfactant, the coatability of the photothermographic material is improved.

By containing a nonionic surfactant on the photosensitive layer side of the support, the storage stability of the fluorine-containing cation compound and the transition metal compound is further improved.

The structure of the present invention will be described in detail below.

The transition metal compounds used in the present invention are IIIa, IVa, Va, VIa, VIIa, VIII, Ib and IIb of the periodic table.
Is an organic or inorganic salt of.

The preferred transition metal ions are Zn ²⁺ , Ni ²⁺ ,
Cd ²⁺ , Mn ²⁺ , V ³⁺ , Co ²⁺ , Fe ³⁺ , especially Zn ²⁺
Is most preferred.

The transition metal compounds of the present invention can be used in the form of various organic or inorganic salts with the above transition metal ions. For example, sulfate, nitrate, hydrochloride, phosphate,
Inorganic salts such as borate, carbonate and hydroxide, oxalate,
Organic salts such as acetate, formate, citrate and benzoate can be used. As a particularly preferable Zn ²⁺ compound, zinc sulfate, zinc chloride, zinc nitrate, zinc hydroxide, zinc acetate, zinc carbonate and the like are preferably used.

The layer of the above-mentioned transition metal compound added to the photothermographic material is not particularly limited, and may be added to any layer such as a silver halide emulsion layer, an intermediate layer, a protective layer and an undercoat layer.
An intermediate layer, an undercoat layer, a protective layer and the like are preferable, and they may be added to a plurality of layers.

The addition amount of the above-mentioned transition metal compound varies depending on the kind of the metal compound used, but is generally in the range of 0.1 to 100 mmol, preferably 1 to 50 mmol per 1 m ^{2 of the} photothermographic material.

The water-soluble transition metal compound of the present invention is preferably added as an aqueous solution, but compounds having relatively low water solubility, such as zinc carbonate and zinc hydroxide, are averaged by a ball mill, a sand mill or the like. Is preferably added in the form of a solid dispersion of fine particles of 0.1 to 10 μm.

The fluorine-containing cationic surfactant used in the present invention is a compound represented by the following general formula [F].

The general formula _{[F] R f -T-X} + Y - However, R _f is a 1-20 hydrocarbon group having a carbon number of at least one of the hydrogen atoms are replaced with fluorine atoms. T represents a chemical bond or a divalent group. X represents a cationic group and Y represents a counter anion.

[0025]

[Chemical 1]

[0026]

[Chemical 2]

Specific examples of the fluorine-containing cationic surfactant preferably used in the present invention are given below.

[0028]

[Chemical 3]

[0029]

[Chemical 4]

[0030]

[Chemical 5]

In the present invention, it is more preferable to use a particularly insoluble sulfonamide type fluorine-containing surfactant in the same layer as the anionic surfactant. Here, “poorly soluble” means that 2 g of the surfactant is added to 100 cc of H ₂ O at 23 ° C.
After stirring for 1 hour and standing at 23 ° C. for 24 hours, a precipitate is formed, or when a floating material is observed, it is considered to be insoluble. For example, FK-1, FK-8, FK-15, FK-16, and the like correspond, but the present invention is not limited to these and can be divided by the above test.

The photothermographic material of the present invention preferably contains an anionic surfactant in the fluorine-containing cationic surfactant-containing layer from the viewpoint of preventing cissing failure during coating and generation of fine particles.

The anionic surfactant preferably used in the present invention is selected from those represented by the following general formula [A].

General formula [A] R- (K) n-L In the formula, R is an alkyl group having 4 to 24 carbon atoms, an alkenyl group,
It represents an aralkyl group and a fluorohydrocarbon group in which a hydrogen atom of these groups is substituted with a fluorine atom. K represents a divalent linking group, and n represents 0 or 1. L is a sulfonic acid group,
Sulfonic acid ester group, carboxylic acid group, phosphonic acid group,
It represents a phosphonate group, a phosphite group and salts thereof. Specific examples of the divalent group of K will be given below.

[0035]

[Chemical 6]

Specific examples of the anionic surfactant used in the present invention are shown below, but the invention is not limited thereto.

[0037]

[Chemical 7]

[0038]

[Chemical 8]

[0039]

[Chemical 9]

[0040]

[Chemical 10]

[0041]

[Chemical 11]

[0042]

[Chemical 12]

[0043]

[Chemical 13]

[0044]

[Chemical 14]

[0045]

[Chemical 15]

[0046]

[Chemical 16]

Of these, a fluorinated anionic surfactant is preferable, and it is more preferable to use a sulfonamide type fluorinated anionic surfactant.

The fluorine-based anionic surfactant according to the present invention or the fluorine-based cationic surfactant according to the present invention is, for example, US Pat. Nos. 2,559,751 and 2,567,011.
2,732,398, 2,764,602, 2,806,866, 2,8
09,998, 2,915,376, 2,915,528, 2,934,450
No., No. 2,937,098, No. 2,957,031, No. 3,472,894,
No. 3,555,089, No. 2,918,501, British Patent No. 1,143,927,
1,130,822, Japanese Examined Patent Publication No. 45-37304, JP-A-47-9613,
50-121243, 50-117705, 49-134614, 50
-117727, 52-41182, 51-12392 specifications,
Journal of the British Chemical Society (J. Chem. Soc.), 1950, page 2789, 1957.
Year 2574 and 2640, Journal of the American Chemical Society (J. Amer. Chem.
Soc.) Volume 79, page 2549 (1957), Oil Chemistry (J. Japan. Oil Che
mistsSoc.) Volume 12, page 653, Journal of Organic Chemistry (J.Org.Che)
m.) Volume 30, page 3524 (1965) and the like. Among these fluorine-containing surfactants according to the present invention, a certain kind is a trade name of Megafac F from Dainippon Ink and Chemicals, Inc., and Fluorad FC from Minnesota Mining and Manufacturing Company. Under the trade name of Imperial Chemical Industry under the name of Monflor under the trade name of EIDupont from Nemeras & Company under the name of Zonyls or from Farbeberke Hoechst under the name of Licowet. VPF
It is marketed under the brand name.

The total amount of the fluorine-containing cation activator and the fluorine-containing anion activator used in the present invention is preferably 0.1 to 1000 mg, preferably 0.5 to 3 mg per 1 m ^{2 of the} photothermographic material.
00 mg is preferable, and 1.0 to 150 mg is more preferable. When used in combination, two or more fluorine-containing anion activators and fluorine-containing cation activators may be used in combination.

In addition, a fluorine-containing nonionic activator, a fluorine-containing betaine activator and a hydrocarbon activator may be used in combination.

The addition ratio of the fluorinated anion activator and the fluorinated cation activator of the present invention is 1:10 to 10: 1.
Is preferred. More preferably, it is 3: 7 to 7: 3.

The place where the fluorine-containing anion activator and the fluorine-containing cation activator of the present invention are added is not particularly limited and may be either a photosensitive layer or a non-photosensitive layer, but a protective layer is preferable.

The fluorinated cationic surfactant and the anionic surfactant of the present invention are preferably added to the protective layer, but can be added to layers other than the protective layer. Also,
The fluorine-containing cation-based surfactant and the anion-based surfactant of the present invention may be used alone in each layer that is not used in combination. Of course, it is also possible to use a surfactant other than the present invention (for example, a non-fluorine-containing cationic surfactant, a nonionic surfactant, etc.) in any layer.

The photothermographic material of the present invention preferably contains a nonionic surfactant on the photosensitive layer side.

When the nonionic surfactant is contained, the fogging increase due to long-term storage at a relatively low temperature due to the combined use of the transition metal compound and the fluorine-containing cationic surfactant is further improved. Not only does it have the advantage that the transfer rate and peelability are improved.

The nonionic surfactant preferably used in the present invention is a polyethylene glycol nonionic surfactant represented by the following general formula [N].

[0057] In the general formula _{[N] R 30 -J- (CH} 2 CH 2 O) p-H type, R ₃₀ represents an alkyl group, an alkenyl group, an aryl group, or R ₃₁ CO- group, J represents an oxygen atom Or −N (R ₃₂ ) −
Represents a group. R ₃₁ represents an alkyl group, R ₃₂ represents a hydrogen atom,
Alkyl group, an aryl group, or - represents a _{(CH 2 CH 2 O) q} -H. p and q each represent an integer of 3 to 100.

In the general formula [N], the alkyl group, alkenyl group, aryl group represented by R ₃₀ , the alkyl group represented by R ₃₁ and the alkyl group or aryl group represented by R ₃₂ are each a substituent. You may have.

Specific examples of the polyethylene glycol nonionic surfactant represented by the general formula [N] are shown below.

[0060]

[Chemical 17]

In addition to the above, Japanese Patent Publication No. 1-59572, 42
The compounds described at page, column 84, line 27 to page 43, column 86, line 31 can also be preferably used in the present invention.

The amount of the nonionic surfactant added is 0.01 to ² g, preferably 0.05 to ² g, per 1 m ^{2 of the} photothermographic material.
It is in the range of 1 g.

The photothermographic material of the present invention will be described below.

The heat-developable light-sensitive material of the present invention has on a support at least one light-sensitive layer containing a light-sensitive silver halide and a dye-donor substance that releases or forms a diffusible dye during heat development. However, it is preferable to form or release yellow, magenta and cyan diffusible dyes.
An intermediate layer is preferably provided between the photosensitive layers which are composed of one or more photosensitive layers and which form or release dyes of different hues, from the viewpoint of preventing color mixture.

As the photosensitive silver halide used in the photothermographic material of the present invention, those known in the art can be used. Examples thereof include silver chloride, silver bromide, silver iodobromide and silver chlorobromide. Alternatively, silver chloroiodobromide can be used.

The silver halide may have a uniform composition from the inside to the surface of the grain, or may be a silver halide having a composition which changes continuously or stepwise inside and on the surface.

The shape of silver halide may be tabular, cubic, spherical, octahedral, dodecahedron, tetrahedral or the like having a clear crystal habit or not.

Further, for example, US Pat. Nos. 2,592,250 and 3,22.
0,613, 3,271,257, 3,317,322, 3,511,622
No. 3,531,291, No. 3,447,927, No. 3,761,266,
The internal latent image type silver halide emulsions described in JP-A-3,703,584, JP-A-3736,140, JP-A-3,761,276, JP-A-52-15661 and JP-A-55-127549 can also be used.

The light-sensitive silver halide can be added with a metal ion species such as iridium, gold, rhodium, iron and lead in the form of a suitable salt at the stage of grain formation.

The photosensitive silver halide emulsion has a grain size of about 0.
The thickness is 02 to 2 μm, preferably about 0.05 to 0.5 μm.

In the present invention, as a method for preparing a photosensitive silver halide, a photosensitive silver salt forming component such as a water-soluble halide is allowed to coexist with an organic silver salt described below, and a part of the organic silver salt is subjected to photosensitive halogenation. It can also be formed by converting a part of silver.

The photosensitive silver halide emulsion is obtained by chemically sensitizing the surface of silver halide grains with a known sensitizer (eg, active gelatin, inorganic sulfur, sodium thiosulfate, thiourea dioxide, sodium chloroaurate). It is also possible to carry out chemical sensitization in the presence of a nitrogen-containing heterocyclic compound or a mercapto group-containing heterocyclic compound.

Further, the light-sensitive silver halide can be spectrally sensitized to blue, green, red and near-infrared light by a known spectral sensitizing dye such as cyanine and merocyanine used in ordinary photography.

These sensitizing dyes are used in an amount of 1 μmol to 1 mol, preferably 10 μmol to 0.1 mol, per mol of silver halide.
Can be added at any time during the formation of silver halide grains, the removal of soluble salts, before the start of chemical sensitization, at the time of chemical sensitization, or after the end of chemical sensitization.

Examples of the dye-donor substances used in the photothermographic material of the present invention include those disclosed in JP-A-61-61157 and 61-611.
No. 58, No. 62-44738, No. 62-129850, No. 62-129851,
No. 62-129852, No. 62-169158, couplers forming diffusible dyes described in Japanese Patent Application No. 1-200859, for example, leuco dyes described in JP-A No. 61-88254, U.S. Pat. 95
Azo dyes described in No. 7, or U.S. Patent Nos. 4,463,079, 4,
439,513, JP-A-59-60434, 59-65839, 59-71
046, 59-87450, 59-123837, 59-124329
No. 59-165054, No. 59-165055, etc. In particular, a compound that forms a diffusible dye by a coupling reaction is preferable. For example, JP-A-2-863, page 9, lower left column 2
It is represented by the general formula (a) in the line.

Among them, a polymer coupler having a polymer chain having a repeating unit derived from a monomer represented by the general formula (b) described in the lower right column, line 8 of the same publication is preferable.

Examples of positive type dye-donor substances include, for example:
JP 59-55430, 59-165054, 59-154445,
59-116655, 59-124327, 59-152440, 64-13
There are compounds described in each publication such as No. 546.

The above dye-providing substances may be used alone or in combination of two or more kinds. Further, in the present invention, a polymer UV agent may be contained in the same layer together with the above-mentioned dye-providing substance, and in that case, the dye-providing substance and the polymer UV agent may be simultaneously dispersed.

The photothermographic material of the present invention is, for example,
A dye-donor substance is contained in a microcapsule together with the polymerizable compound described in JP-A-2-293753 and JP-A-2-308162, and the resulting compound is thermally developed to image-wise the polymerization reaction of the polymerizable compound. Alternatively, it can also be applied to a photothermographic material of a type in which the microcapsules are cured in the reverse image to change the diffusivity of the dye-donor substance to the image receiving layer to form an image.

In the photothermographic material of the present invention, a known organic silver salt can be used for the purpose of increasing sensitivity and improving developability.

The organic silver salt that can be used in the present invention is
For example, JP-B-43-4921, JP-A-49-52626, and JP-A-52-14
1222, 53-36224, 53-37626, 53-36224,
53-37610 and other publications and U.S. Patent 3,330,633,
No. 3,794,496, No. 4,105,451, etc., silver salts of long-chain aliphatic carboxylic acids and silver salts of carboxylic acids having a heterocycle (for example, silver behenate, α- (1-phenyltetrazolethio)). Silver acetate), Japanese Patent Publication No. 44-26582, No. 45-
No. 12700, No. 45-18416, No. 45-22815, JP-A-52-1373
No. 21, No. 58-118638, No. 58-118639, U.S. Pat.
Examples thereof include silver salts of compounds having an imino group described in JP-A No. 274 and the like, acetylene silver described in JP-A No. 61-249044, and the like.

Particularly, a silver salt of a compound having an imino group is preferable, and for example, a silver salt of benzotriazole and its derivative (for example, silver benzotriazole, silver 5-methylbenzotriazole, etc.) is particularly preferable.

A reducing agent is preferably used in the photothermographic material of the invention. The reducing agent preferably used is selected from those conventionally known for photothermographic materials depending on the developing mechanism and the dye forming or releasing mechanism.
The reducing agent referred to herein also includes a reducing agent precursor that releases the reducing agent during thermal development.

Examples of the reducing agent which can be used in the present invention include US Pat. Nos. 3,351,286, 3,761,270 and US Pat.
No. 3,764,328, No. 3,342,599, No. 3,719,492,
Research Disclosure No. 12,146, No. 15,108,
15,127, and JP-A-56-27132, 53-135628,
No. 57-79035 p-phenylenediamine system and p-
Aminophenol-based developing agent, phosphoric amide phenol-based developing agent, sulfonamide aniline-based developing agent, and hydrazone-based developing agent, phenols, sulfonamide phenols, polyhydroxybenzenes, naphthols, hydroxybisnaphthyls, methylenebisphenol , Ascorbic acids, 1-aryl-3-pyrazolidones, hydrazones, and precursors of the above various reducing agents.

The dye-providing substance can also serve as the reducing agent.

A particularly preferred reducing agent is JP-A-56-146133.
And N- (pN ′, N′-dialkylamino) phenylsulfamate and its derivatives described in JP-A No. 62-227141 and JP-A No. 2-863, page 7, lower left column, line 6 To the compounds described in the lower right column of page 8.

A thermal solvent may be used in the photothermographic material of the present invention for the purpose of accelerating the transfer of dye and other purposes. The thermal solvent is a compound that has a function of liquefying during thermal development and promoting thermal development and thermal transfer of a dye, and is preferably in a solid state at room temperature.

Examples of the thermal solvent that can be used in the present invention include US Pat. Nos. 3,347,675, 3,667,959 and 3,347,675.
438,776, 3,666,477, Research Disclosure No. 17,643, JP-A-51-19525, 53-24829, 5
3-60223, 58-118640, 58-198038, 59-2295
No. 56, No. 59-68730, No. 59-84236, No. 60-191251,
No. 60-232547, No. 60-14241, No. 61-52643, No. 62-78
554, 62-42153, 62-44737, 63-53548,
63-161446, JP-A 1-224751, 2-863, 2-12
Examples thereof include the compounds described in each publication such as 0739 and 2-123354. Specifically, urea derivatives (urea, dimethylurea, phenylurea, etc.), amide derivatives (eg, acetamide, stearylamide, p-toluamide, p-propanoyloxyethoxybenzamide, etc.), sulfonamide derivatives (eg, p-toluene). Sulfonamide etc.) and polyhydric alcohols (eg 1,6 hexanediol, pentaerythritol, polyethylene glycol etc.) are preferably used.

The above thermal solvent can be added to any layer such as a photosensitive silver halide emulsion layer, an intermediate layer, a protective layer, or an image receiving layer of an image receiving material. Wt% to 500 wt%, more preferably 20 wt% to 2
It is 00% by weight.

The hydrophilic binder used in the photothermographic material of the present invention is, for example, JP-A-2-86310.
The binders described in the upper right column, line 14 to the lower left column, line 10 can be used including preferable combinations.
Particularly preferred binders are gelatin, polyvinylpyrrolidone and combinations thereof.

In addition to the above, various additives can be added to the photothermographic material of the present invention, if necessary.

Examples of development accelerators include JP-A-59-177.
550, 59-111636, 59-124333, 61-72233
No. 61-236548, JP-A 1-152454, JP-A 61-1596.
No. 42, JP-A-1-104645 and Japanese Patent Application No. 1-110767, or a development accelerator releasing compound, or a metal ion having an electronegativity of 4 or more described in JP-A-1-104645 can also be used. ..

Examples of the antifoggant include US Pat.
645,739, higher fatty acids, secondary mercury salts described in JP-B-47-11113, N-halides described in JP-A-51-47419, US Pat. No. 3,700,457, JP-A-51- Fifty
No. 725, Japanese Patent Application No. 1-69994, mercapto compound-releasing compounds described in 1-104271; arylsulfonic acid described in JP-A-49-125016; lithium carboxylate described in 51-47419; British Patent 1,455,271 and oxidizers described in JP-A-50-101019, sulfinic acids and thiosulfonic acids described in 53-19825, thiouracils described in 51-3223, sulfur described in 51-26019, sulfur, No. 51-42529, No. 51-811
No. 24, and No. 55-93149, disulfides and polysulfides, No. 51-57435, rosins or diterpenes, No. 51-104338, polymer acids having a carboxyl group or a sulfonic acid group, U.S. Pat. Thiazolythion described in 4,138,265, JP-A-54-51821 and JP-A-55-142,331.
No. 3, U.S. Pat. No. 4,137,079, triazoles, JP-A-55-140883, thiosulfinic acid esters, JP-A-59-46641, 59-57233, and 59-57234.
-Or tri-halide, a thiol compound described in JP-A-59-111636, a hydroquinone derivative described in JP-A-60-198540 and 60-227255, and a hydrophilic group described in JP-A-62-78554 Antifoggants, polymer antifoggants described in JP-A No. 62-121452, anti-foggants having a ballast group described in JP-A No. 62-123456, and colorless couplers described in JP-A No. 1-161239. Be done.

Examples of the base precursor include, for example, JP-A Nos. 56-130745, 59-157637, 59-166943, and 59-59.
180537, 59-174830, 59-195237, 62-10824
No. 9, No. 62-174745, No. 62-187847, No. 63-97942,
The compounds and base-releasing techniques described in JP-A-63-96159 and JP-A-1-68746 are cited.

Various known photographic additives other than those mentioned above can be used in the photothermographic material of the present invention. Examples thereof include antihalation dyes, antiirradiation dyes, colloidal silver, optical brighteners, Hardeners, antistatic agents, surfactants, inorganic and organic matting agents, anti-fading agents, UV absorbers, antifungal agents, white background color tone adjusting agents, may contain solid particulates adsorbing contaminants such as activated carbon. it can.

These various additives can be appropriately added not only to the photosensitive layer but also to any constituent layer such as an intermediate layer, an undercoat layer, a protective layer or a back layer.

As the support used in the photothermographic material of the present invention, for example, the supports described in JP-A-2-863, page 12, upper left column, line 15 to upper right column, line 1 can be used. .. Preferably, a polyethylene terephthalate support or a paper support such as cast coated paper or baryta paper is used.

In the back layer of the photothermographic material of the present invention, either a hydrophilic binder such as gelatin or a hydrophobic binder such as polyester can be used, but the hydrophilic binder is preferred. The back layer may be composed of one layer or two or more layers, and the fluorine-containing cationic surfactant and / or anionic surfactant of the present invention may be added to the uppermost layer of the back layer.

The dye image-receiving material used in combination with the photothermographic material of the present invention comprises a support and an image-receiving layer having a dye-receiving ability provided thereon.

The image-receiving layer is roughly classified into the case where the binder itself constituting the image-receiving layer has a dye-receiving ability and the case where a mordant capable of receiving the dye is contained in the binder. When the binder has a dye-accepting ability, the substance preferably used has a glass transition temperature of about 40 ° C. or higher and about 250.
Those formed of a polymer having a temperature of ℃ or below are preferable, and specifically, "Polymer Handbook Second Edition" (Joy Brand Wrap, E.H.
Inmargat), John Willie and Sons Publishing {Polymer Handbook 2nd. Ed. (J. Brandrup, E.
H. Immergut ed.) John Wily & Sons} synthetic polymers having a glass transition temperature of about 40 ° C. or higher are generally useful, and generally, the molecular weight of the polymer is 2,000 to 20.
A value of about 0,000 is useful. These polymers may be used alone or in combination of two or more kinds, and may be a copolymerizable polymer having two or more kinds of repeating units.

Specifically, JP-A-2-863, page 14, upper left column 1
The polymers described from the 4th line to the 14th line in the upper right column can be used including the preferable polymers.

Further, in the image receiving material in which the image receiving layer contains a mordant in the binder, a polymer containing a tertiary amine or a quaternary ammonium salt is preferably used as the mordant. For example, US Pat. 64-64
Examples thereof include compounds described in Japanese Patent No. 13546. As the binder used for holding these mordants, hydrophilic binders such as gelatin and polyvinyl alcohol are preferably used.

A dye receiving layer obtained by dispersing a hydrophobic polymer latex having dye receiving ability in a hydrophilic binder in a form similar to the image receiving layer having the mordant in the binder can also be used in the present invention.

The image-receiving material of the present invention may have a single image-receiving layer provided on a support, or may have a plurality of constituent layers coated thereon, in which case all of them are dyes. It can be an image receiving layer, or only a part of the constituent layers can be an image receiving layer.

Various known additives can be added to the image receiving material of the present invention. Examples of such additives include stain inhibitors, ultraviolet absorbers, optical brighteners, image stabilizers, development accelerators, antifoggants, pH regulators (acid and acid precursors, base precursors, etc.), heat Solvents, organic fluorine compounds, oil droplets, surfactants, hardeners, matting agents, various metal ions and the like can be mentioned.

When the image-receiving material has a back layer, the fluorine-containing cationic surfactant and the anionic surfactant of the present invention may be added to the back layer to improve the transportability during heat development. 2 back layers
It may be composed of more than one layer, and when it is composed of two or more layers, the fluorine-containing cationic surfactant and the anionic surfactant of the present invention are preferably added to the uppermost layer. As the binder for the back layer of the image receiving material, either a hydrophilic binder or a hydrophobic binder can be used.

The photothermographic material of the present invention can be exposed by a known exposure means suitable for the color sensitivity of the photosensitive material.

As an exposure light source that can be used, those described in JP-A-2-863, page 12, lower left column, lines 13 to 16 can be used, preferably a laser light source, CR
T light source and LED are used. The semiconductor laser, SHG element (second harmonic generating element) and the photothermographic material of the present invention are preferably 70 to 20 after imagewise exposure or at the same time as exposure.
0 ℃, more preferably 90 ~ 170 ℃, preferably 1 ~ 180
It is heat-developed for 2 seconds, more preferably 2 to 120 seconds to form a dye image. The transfer of the diffusible dye to the image receiving material may be carried out at the same time as the heat developing by bringing the image receiving layer surface of the image receiving material into close contact with the photosensitive layer side of the photosensitive material during the heat developing,
Further, the dye may be transferred by bringing the image-receiving material into close contact with the photosensitive material after heat development, and further, after supplying water, the photosensitive material and the image-receiving material may be brought into close contact with each other. In addition, 70-160 before exposure
Preheat the light-sensitive material in the range of ℃, or JP-A-60-14333
As described in No. 8 and No. 61-162041, immediately before development, at least one of the light-sensitive material and the image-receiving material is heated at 80 to 120 ° C.
It is also possible to preheat in the temperature range of.

When the heat-developable photosensitive material of the present invention is thermally developed, known heating means can be applied. For example, JP-A-2-863, page 13, upper left column, lines 12 to 19 The described method, the method by far infrared heating, etc. can be used.

[0110]

EXAMPLES Examples of the present invention will be shown below, but the embodiments of the present invention are not limited thereto.

Example-1 [Preparation of Photothermographic Material] A photothermographic material 1 having the layer constitution shown below was prepared on a photographic baryter paper having a thickness of 160 μm.

Here, the addition amount of each material is shown by the amount per 1 m ^{2 of the} photothermographic material.

The photosensitive silver halide emulsion and the organic silver salt are each expressed in terms of silver.

(The amounts of all the following additives used are also the same.) (Layer Constitution of Photothermographic Material 1) Subbing Layer Polyphenylene ether 2.0 g Polystyrene 2.0 g Antifoggant-2 1.0 g First layer (red photosensitive material) Layer) Benzotriazole silver 0.2g Dye donor (3) 0.9g Red-sensitive silver halide emulsion 0.23g (Ag) Gelatin 1.0g DAP 0.04g Thermal solvent-A 2.1g Anti-irradiation dye-2 0.01g Potassium bromide 0.005 g Second layer (first intermediate layer) Gelatin 0.05g Activated carbon 0.02g Reducing agent 1.42g Third layer (green light-sensitive layer) Benzotriazole silver 0.26g Dye-donor (2) 0.49g Green-sensitive silver halide emulsion 0.21g ( Ag) Gelatin 1.0g Thermal solvent-A 0.4g Anti-irradiation dye 0.02g Sodium chloride 0.002g DAP 0.08g 4th layer (2nd intermediate layer) Gelatin 0.82g UV absorber-1 0.3g Yellow filter dye 0.26g 5th Layer (blue photosensitive layer) Ben Triazole silver 0.41g Dye-donor (1) 1.0g Blue-sensitive silver halide emulsion 0.21g (Ag) Gelatin 1.1g Thermal solvent-A 0.8g 6th layer (protective layer) Gelatin 0.4g Polyvinylpyrrolidone (K-30) 0.1 g ZnSO ₄ (amount shown in Table 1) DAP 0.1 g UV absorber-1 0.4 g Each addition amount represents the amount added per 1 m ² . For each layer,
It contains 0.03 g of bisvinylsulfonylmethyl ether as a hardening agent per 1 g of gelatin, and the reducing agent is a mixture of reducing agent-1 and reducing agent-2 in a ratio of 7: 3 (weight ratio).

Table 1 shows the types and amounts of the surfactants used in the fourth and sixth layers. The surfactants used in the first to third layers and the fifth layer are as follows.

First layer A-30 0.018g Second layer A-30 0.008g Third layer A-30 0.015g Fifth layer A-30 0.014g Structure of additive used in photosensitive layer of photothermographic material The formula is shown below.

[0117]

[Chemical 18]

[0118]

[Chemical 19]

[0119]

[Chemical 20]

[Benzotriazole silver emulsion] Prepared by simultaneous mixing of an aqueous solution of ammoniacal silver nitrate and benzotriazole (containing 0.2 mol of ammonia water with respect to benzotriazole) in a 10% aqueous solution of phenylcarbamoyl gelatin at 50 ° C., and the addition was completed. Needle-like crystals (width 0.1-0.2μm, length 0.5-2μ)
m) got.

To this was added ST-2 as a stabilizer in an amount of 20 mg per mol of benzotriazole silver. The photosensitive silver halide emulsion (AgBrCl) used is shown below.

Item Blue-sensitivity Green-sensitivity (GEM-1) Red-sensitivity Halogen composition (Br mol%) 70 60 70 Particle shape Hexagonal cubic Cubic average particle size * 1 0.30 μm 0.19 μm 0.20 μm Particle size Distribution coefficient * 2 0.15 0.17 0.13 Surface chemical sensitization method * 3 S + Au S S + Au Stabilizer ST-1 ST-1 ST-2 Sensitizing dye BSD-1 GSD-1 RSD-1 * 1 Diameter in sphere conversion * 2 grains Diameter distribution coefficient = (particle size distribution standard deviation) / (average particle size) * 3 S + Au: gold-sulfur sensitization with sodium thiosulfate and potassium chloroaurate S: sulfur sensitization with sodium thiosulfate To each silver emulsion, 10 ^-6 mol of sodium iridium (IV) chloride was added per 1 mol of silver halide during grain formation.

ST-1: 5-methyl-1,3,3a, 7-tetrazaindene The chemical sensitization of each was carried out in the presence of a sensitizing dye.

[0124]

[Chemical 21]

Further, in the above-mentioned heat-developable light-sensitive material-1, heat-developable light-sensitive materials 2 to 20 in which the surfactants used in the first to sixth layers were changed as shown in Table 1, were simultaneously prepared.

The obtained photothermographic material was heated at 40 ° C. and relative humidity.
It was stored at 65% for 30 hours, and was cured to the desired degree of dura.
(The amount of water absorption at the photosensitive layer side at 30 ° C is 1.7 to 1.9 with respect to the total amount of gelatin at the photosensitive layer side) [Preparation of dye image receptor material] On a baryter paper support having a thickness of 160 μm, the following composition was used. The image-receiving layer was solvent-coated with methyl ethyl ketone as a solvent to prepare a dye image-receiving material-1. The amount added is the amount per 1 m ² of the image receiving material. Polyvinyl chloride 12.0g Thermal solvent-B 3.0g

[0127]

[Chemical formula 22]

[Evaluation of Photothermographic Material] The obtained photothermographic material-1 was exposed to monochromatic light of blue, green and red, and then exposed to 155
A heat development treatment was carried out at 60 ° C. for 60 seconds. Then, the image receiving layer surface side of the dye image receiving material-1 is superposed on the photosensitive layer side of the photothermographic material and heated and pressed at 120 ° C. for 20 seconds to transfer the dye image to the image receiving layer. It was peeled off from the image receiving material. The maximum and minimum densities of the dye image obtained on the image receiving layer were measured with green monochromatic light, and the results shown in Table 1 were obtained.

On the other hand, samples of heat-developable photosensitive materials 1 to 20 stored at 60 ° C. and 40% relative humidity for 3 days and 35 ° C. and 60% relative humidity
The same treatment was applied to the sample stored for 3 months and the results shown in Table 1 were obtained.

[0130]

[Table 1]

From the results shown in Table 1, the photothermographic materials 10 to 12 to which only ZnSO ₄ was added exhibited an excellent antifoggant effect under the condition of forced deterioration storage, but when stored at 35 ° C. for 3 months. Has an insufficient antifogging effect. On the other hand, it can be seen that the photothermographic material in which zinc sulfate and the fluorine-containing cationic surfactant of the present invention are used in combination can obtain the antifoggant effect even when stored under low temperature conditions.

Further, it can be seen that Samples 19 and 20 in which the nonionic surfactant is added to the fourth layer give higher Dmax.

Example-2 In the photothermographic material-13 prepared in Example-1, the photothermographic materials 21 to 27 in which ZnSO ₄ added to the sixth layer was changed to the transition metal compound shown in Table 2 were used. Was prepared in the same manner as in Example-1.

Zinc hydroxide and zinc carbonate were poured and dispersed by a ball mill and added.

The storage performance was examined by the method described in Example-1, and the results shown in Table 2 were obtained.

[0136]

[Table 2]

From the results shown in Table 2, it can be seen from the results of the immediate samples and changes in Dmin stored at 35 ° C. for 3 months that the zinc compound is the most excellent transition metal compound. Further, it can be seen that the photothermographic material containing the transition metal compound added as solid particles also exhibits excellent storage stability.

[0138]

According to the present invention, it is possible to provide a photothermographic material which suppresses the generation of fog when stored at a relatively low temperature, and has improved storability and coatability.

Claims (3)

[Claims] 1. A photothermographic material comprising, on a support, at least one photosensitive layer containing a binder, a photosensitive silver halide, and a dye-donor substance that releases or forms a diffusible dye during thermal development. A photothermographic material, wherein at least one layer on the side of the photosensitive layer with respect to the support contains a fluorinated cation compound and a transition metal compound. 2. The photothermographic material according to claim 1, wherein the fluorinated cation-based compound-containing layer further contains an anionic surfactant. 3. The photothermographic material according to claim 1, which comprises a nonionic surfactant on the side of the photosensitive layer with respect to the support.