JPH11194447A - Heat-developable photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance sensitivity and storage stability for a long time before and after heat development by chemically sensitizing photosensitive silver salt in the presence of a specified organic gold compound. SOLUTION: This heat-developable photosensitive material contains at least the photosensitive silver salt, an organic silver salt, a reducing agent, and a binder on a support, and the photosensitive silver salt is a silver halide subjected to chemical sensitization in the presence of the organic gold compound. The photosensitive silver salt functions as a light sensor and it is preferred to have a small average grain diameter, and to be concrete, it is preferred to be <=0.1 μm, and further preferably, 0.01-0.1 μm, and it is preferred that the silver halide grains are monodisperse ones and have a monodispersion degree of <=40%, and further preferably, <=30%. The forms of silver halide grains are not specially limited, but it is preferred that a Miller index of a [100] face-occupying rate is high as >=50%, especially, >=70%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photothermographic material having high sensitivity and excellent storage stability, and more particularly to a black-and-white photothermographic material.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making and medical treatment, waste liquid caused by wet processing of an image forming material has been a problem in terms of workability. It is strongly desired to reduce the amount of waste liquid.

[0003] Therefore, there is a need for a technique relating to photothermographic materials for photographic technology, which enables efficient exposure with a laser imagesetter or laser imager and can form a high-resolution, clear black image. I have.

[0004] Such techniques include, for example, US Patent Nos. 3,152,904 and 3,487,075 and D.C. Morgan (Dry Silver Photograph)
hic Materials) ”(Handbook)
of Imaging Materials, Mar
cel Dekker, Inc. 48, 1991)
And the like, a photothermographic material containing an organic silver salt, photosensitive silver halide grains and a reducing agent on a support is known.

[0005]

However, in photothermographic materials, high sensitivity is strongly desired.

However, simply applying a sensitization technique generally used in a conventional photosensitive material which undergoes wet development processing not only easily causes fogging at the time of thermal development, but also causes a problem before the thermal development processing. There is a problem that fogging easily occurs during the storage period.

In these photosensitive materials, after exposure, heat development is usually performed only at 80 to 250 ° C., and fixing is not performed. Therefore, silver halide and organic silver salts remaining in unexposed areas are not removed and are left as they are. It remains in the photosensitive material. When these remaining silver halides and organic silver salts are stored for a long period of time, the fog density of the unexposed portions may increase, the coloring may occur, and the color tone of the developed silver may change to a warm black tone. It was a problem.

Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a photothermographic material and an image recording apparatus which have high sensitivity and excellent long-term storage properties before and after heat development. It is to provide a method.

[0009]

According to the present invention, there is provided a photothermographic material comprising at least a photosensitive silver salt, an organic silver salt, a reducing agent and a binder on a support. Wherein the photosensitive silver is silver halide chemically sensitized in the presence of an organic gold compound.

In a preferred embodiment of the present invention, the organic gold compound is a compound having at least one sulfur atom as an atom constituting the compound.

In a more preferred embodiment of the present invention, the organic gold compound is at least one compound represented by the following general formula (I) or (II). In the general formula _{(I) (H r Au m} [L] n [X] p) q [ Formula, L represents a organic compound ligand having a thione or thiol group, X represents an anion. r is 0, 1 or 2, m is 1 or 2, p is 1, 2 or 3, p is 0, 1, 2
Alternatively, 3 and q each represent an integer of 1 to 4. General formula (II) E-SO ₂ S-Au (I) -SG [wherein E and G may be the same or different, and represent an aliphatic group, an aromatic group or a heterocyclic group. Represent. As another preferred embodiment of the present invention, the following general formula (III)
Or it contains at least one compound represented by (IV).

[0012]

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Wherein (A ₁ ) and (A ₁ ) ′ are —SO
₃ M or -COOM, wherein M represents a hydrogen atom, a metal atom, an ammonium group or a phosphonium group.
(A ₁ ) and (A ₁ ) ′ may be the same or different. m represents an integer of 1 to 10. (A ₂ ) and (A
₂ ) 'represents an electron-withdrawing group, which may be the same or different. n represents an integer of 1 to 10. (A ₃ ) and (A ₃ ) ′ represent a functional group containing a sulfur or selenium atom capable of binding to a silver ion, and (A ₃ ) and (A ₃ ) ′ may be the same or different. r is 1 or 2. Y represents an aliphatic hydrocarbon or an aromatic hydrocarbon,
X represents a sulfur atom or a selenium atom. ]

An image recording method according to the present invention for solving the above-mentioned problems is to write the above photothermographic material by exposure for a time of 10 ^-2 seconds or less and to heat it at a developing temperature of 80 ° C or more and 250 ° C or less. In a more preferred embodiment, the light used for the exposure is a laser beam.

[0015]

Embodiments of the present invention will be described below in detail. The photothermographic material of the present invention forms a photographic image using a photothermographic processing method. For details of the photothermographic material, see, for example, US Pat. No. 3,152,904.
No. 3,457,075 and D.C. Morgan (M
organic silver photographic material (Dry)
Silver Photographic Mate
rial) ”and D.R. Morgan and B.A. "Thermally Processed Silver System" by Shelly
SilverSystems) ”(Imaging Processes and Materials (Imaging)
Processes and Materials) N
Eblette Eighth Edition, Sturge,
V. Walworth, A .; Shepp, 2nd page, 1969) and the like.

Among them, the light-sensitive material used in the present invention is a light-sensitive material which forms an image without performing fixing only by thermal development at a temperature of 80 to 250 ° C. Since the fixing is not performed, the silver halide and the organic silver salt remaining in the unexposed areas remain in the photosensitive material without being removed.

The photosensitive silver salt (silver halide particles) in the present invention functions as an optical sensor. In the present invention, in order to suppress the white turbidity after image formation, and to obtain good image quality, the average particle size is preferably smaller, specifically, the average particle size is preferably 0.1 μm or less,
More preferably 0.01 μm to 0.1 μm, especially 0.0 μm
2 μm to 0.08 μm is preferred. When the silver halide grains are so-called normal crystals having a cubic or octahedral shape, the average grain size refers to the length of the edges of the silver halide grains. In the case of non-normal crystals, for example, in the case of spherical, rod-shaped or tabular grains, it refers to the diameter of a sphere equivalent to the volume of silver halide grains.

The silver halide grains are preferably monodisperse grains. The monodisperse particles referred to herein are particles having a degree of monodispersity of 40% or less, more preferably 30% or less, particularly preferably 0.1% or more and 20% or less.
% Or less.

Monodispersity = (standard deviation of particle size) / (average value of particle size) × 100 In the present invention, the silver halide particles have an average particle size of 0.1.
μm or less and more preferably monodisperse particles,
By setting it in this range, the granularity of the image is also improved.

The shape of the silver halide grains is not particularly limited, but it is preferable that the ratio occupied by the Miller index [100] plane is high, and this ratio is 50% or more, and more preferably 7%.
It is preferably at least 0%, particularly preferably at least 80%. The ratio of the [100] plane of the Miller index is determined by the T.V. method using the dependence of the adsorption of the sensitizing dye on the [111] plane and the [100] plane. Tani, J .; Imaging Sci. , 29,
165 (1985).

The average particle diameter of the monodisperse particles is 0.1 μm.
The following is preferable, and more preferably 0.01 μm to 0.1
μm, particularly preferably 0.02 μm to 0.08 μm.

Another preferred shape of silver halide grains is tabular grains. Here, the tabular grains are:
An aspect ratio (= r / h) of 2 or more when the square root of the projected area of the particle is r μm and the thickness in the vertical direction is h μm. Among them, those having an aspect ratio of 3 or more and 50 or less are preferable.

The average particle diameter of the tabular grains is preferably 0.1 μm or less, and more preferably 0.01 μm to 0.08 μm.
μm is more preferred. These are disclosed in U.S. Pat.
No. 337, 5,314,798, 5,320,9
No. 58 and the like, and the desired tabular grains can be easily obtained. In the present invention, when these tabular grains are used, the sharpness of an image is further improved.

The composition of the silver halide is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide and silver iodide. The photographic emulsion used in the present invention is P.I. Chimie et by Glafkids
Physique Photographique (P
aul Montel, 1967); F. D
Photographic Emuls by uffin
ion Chemistry (The Focal P
Res., 1966); L. Zelikman
Making and Coating by et al
Photographic Emulsion (Th
e Focal Press, 1964) and the like.

That is, any of an acidic method, a neutral method, an ammonia method and the like may be used. In order to form a solution by reacting a soluble silver salt and a soluble halide, a one-side mixing method, a double-mixing method, a combination thereof and the like are used. Either may be used.

The silver halide may be added to the image forming layer by any method, and the silver halide is arranged so as to be close to the reducible silver source.

The silver halide may be prepared by converting part or all of the silver in the organic silver salt to silver halide by the reaction of the organic silver salt with a halogen ion,
Silver halide may be prepared in advance and added to a solution for preparing an organic silver salt, or a combination of these methods is possible, but the latter is preferred.

In general, the silver halide is preferably contained in an amount of 0.75 to 30% by weight based on the organic silver salt.

The silver halide used in the present invention includes VIB, VIIB, VI belonging to transition metals of the Periodic Table of the Elements.
It preferably contains ions or complex ions of metals belonging to groups II and IB. The above metals include Cr, W
(The above-mentioned VIB group): Re (VIIB group): Fe, Co,
Ni, Ru, Rh, Pd, Os, Ir, Pt (VI
II): Cu and Au (above IB) are preferable, and when used for a photosensitive material for plate making, Rh, Re, and
It is preferable to be selected from Ru, Ir, and Os.

These metals can be introduced into the silver halide in the form of a complex. In the present invention, the transition metal complex is preferably a six-coordinate complex represented by the following general formula.

In the general formula [ML ₆ ] ^m , M is a group VIB, VIIB, or VII of the periodic table.
A transition metal selected from Group I and Group IB elements, L represents a bridging ligand, and m represents 0, -1, -2 or -3.

Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and alcohol. Each ligand of
Nitrosyl, thionitrosyl and the like can be mentioned, and preferred are aquo, nitrosyl and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands. L may be the same or different.

Particularly preferred examples of M are rhodium (Rh), ruthenium (Ru), rhenium (Re) and osmium (Os).

The following are specific examples of the transition metal coordination complex. ^{_{1: [RhCl 6] 3- 2}} : [RuCl 6] 3- 3: [ReCl 6] 3- 4: [RuBr 6] 3- 5: [OsCl 6] 3- 6: [CrCl 6] 4- 7: _{[Ru (NO) Cl 5]} 2- 8: [RuBr 4 (H 2 O)] 2- 9: [Ru (NO) (H 2 O) Cl 4] - 10: [RhCl 5 (H 2 O)] ^{2- 11: [Re (NO)} Cl 5] 2- 12: [Re (NO) CN 5] 2- 13: [Re (NO) ClCN 4] 2- 14: [Rh (NO) 2 Cl 4] - 15: [Rh (NO) ( H 2 O) Cl 4] - 16: [Ru (NO) CN 5] 2- 17: [Fe (CN) 6] 3- 18: [Rh (NS) Cl 5] 2 ^{- 19: [Os (NO)} Cl 5] 2- 20: [Cr (NO) Cl 5] 2- 21: [Re (NO) Cl 5] - 22: [Os (NS) Cl 4 (TeCN)] 2 ^{- 23: [Ru (NS)} C ^{_{5] 2- 24: [Re (}} NS) Cl 4 (SeCN)] 2- 25: [Os (NS) Cl (SCN) 4] 2- 26: [Ir (NO) Cl 5] 2-

One of these metal ions or complex ions may be used, or two or more of the same and different metals may be used in combination.

The content of these metal ions or complex ions is generally 1 to 1 mol per mol of silver halide.
The amount is suitably from ^10-9 to ^1-10-2 mol, preferably 1 mol.
X 10 ^-8 to 1 X 10 ^-4 mol.

The compound which provides these metal ions or complex ions is preferably added during silver halide grain formation and incorporated into silver halide grains. Preparation of silver halide grains, that is, nucleation and growth , Physical aging,
Although it may be added at any stage before and after chemical sensitization, it is particularly preferable to add at the stage of nucleation, growth, and physical ripening,
Further, it is preferably added at the stage of nucleation and growth, most preferably at the stage of nucleation.

In the addition, it may be added in several divided portions, may be added uniformly in silver halide grains, or may be added to silver halide grains.
-306236, 3-167545, 4-76
No. 534, No. 6-110146, No. 5-273683
As described in Japanese Patent Application Laid-Open No. H10-284, etc., the particles can be contained in the particles with a distribution. Preferably, a distribution can be provided inside the particles.

These metal compounds can be added by dissolving them in water or a suitable organic solvent (eg, alcohols, ethers, glycols, ketones, esters, amides). A method in which an aqueous solution of a powder or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble silver salt solution or a water-soluble halide solution during particle formation and placed, or a silver salt solution and a halide solution are used. When mixed simultaneously, a third aqueous solution is added to prepare silver halide grains by a three-liquid simultaneous mixing method, a method in which a required amount of an aqueous solution of a metal compound is charged into a reaction vessel during grain formation, or halogen is added. There is a method in which another silver halide grain doped with a metal ion or a complex ion in advance at the time of preparing silver halide is added and dissolved. In particular, a method of adding an aqueous solution of a powder of a metal compound or an aqueous solution in which a metal compound and NaCl and KCl are dissolved together is added to a water-soluble halide solution. When adding to the particle surface, a required amount of an aqueous solution of a metal compound can be charged into the reaction vessel immediately after the formation of the particles, during or at the end of physical ripening, or at the time of chemical ripening.

The silver halide grains of the present invention have been subjected to chemical sensitization in the presence of an organic gold compound. Chemical ripening or chemical sensitization process conditions such as pH, pAg, temperature,
There is no particular limitation on the time and the like, and the reaction can be performed under conditions generally performed in the art.

For chemical sensitization, it is preferable to use an organic gold compound containing at least one sulfur capable of reacting with silver ions. As the organic gold compound containing at least one sulfur, gold thiosulfate, gold thiocyanate, or the like can be used.

As preferred organic gold compounds in the present invention, those represented by the general formula (1) or (II) can be mentioned. When such an organic gold compound is used, the ratio of gold adsorbed or reacted on the surface of silver halide grains increases, and the ratio of gold present in the binder can be reduced. Here, the binder is a dispersion medium such as gelatin or polymer latex which is a substance to be contained other than the silver halide grains contained in the silver halide photographic material, and various photographic additives dispersed in the dispersion medium. Agents shall be included.

Next, the organic gold compound represented by formula (1) or (II) will be described in detail.

In the above general formula (1), the anion group represented by X includes a halogen ion (for example, fluorine, chlorine, bromine, iodine ion), a perchlorate ion, a borofluoride ion, a sulfate ion, Examples include groups such as nitrate ion and thiocyanate ion.

The 5- or 6-membered heterocyclic ligand represented by L is an anionic, cationic or neutral monocyclic group and is represented by the following formula (IA) or (IB) ) Is selected.

[0046]

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In the general formulas (IA) and (IB), Y ₁
And Y ₂ each represent an oxygen atom, a sulfur atom, a selenium atom or a ＮＲNR ₁ group, and Z ₁ , Z ₂ , Z ₃ , Z ₄ and Z ₅ each represent

[0048]

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＝ CHSH, ＮＲNR ₁ , —N ＝ group, oxygen atom, sulfur atom or selenium atom, and at least one of Z _{1 to} Z ₄ represents ＝ C ＝ W group or ＣＨCHSH group. W represents an oxygen atom, a sulfur atom, a selenium atom or an NR ₁ group.
R ₁ represents a hydrogen atom, an alkyl group, an aryl group, or a heterocyclic group; R ₂ and R ₃ each represent an alkyl group, an aryl group, a heterocyclic group, a halogen atom, a hydroxyl group, a mercapto group, an alkoxy group, an alkylthio group; , Aryloxy group, arylthio group, heterocyclic oxy group, heterocyclic thio group, amino group, phosphonyl group, carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, sulfo group, imide group, carbamoyl group, sulfamoyl group,
Acyl group, cyano group, acyloxy group, carbamoyloxy group, silyloxy group, ureido group, sulfamoylamino group, nitro group, sulfonyl group, sulfinyl group,
Each group represents an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonamide group, or the like.

In the general formulas (I), (IA) and (IB), specific examples of the 5-membered heterocyclic group formed by Y ₁ , Z ₁ , Z ₂ , Z ₃ and Z ₄ are as follows. , Pyrrole (for example, 2 (IH) -pyrroline, 2-pyrrolidinium,
2 (3H) -pyrroline, groups such as pyronium, etc., imidazoles (eg, groups such as 2 (3H) -imidazoline, 2-imidazolinium, 2 (3H) -imidazoline, imidazolium), oxazoles (eg, 2 ( 3H) -oxazolidine, 2-oxazolinium, groups such as 2 (3H) -oxazoline and oxazolium), isoxazoles (for example, groups such as 3 (2H) -isoxazoline and 3-isoxazolium), and thiazoles (for example) 2 (3
H) -thiazolidine, 2-thiazolium, 2 (3H)-
Groups such as thiazoline and thiazolium), isothiazoles (such as 3 (2H) -isothiazoline and 3-isothiazolium), and selenazoles (such as 2 (3H)-
Groups such as selenazolidine and selenazolium), oxazolidine series (for example, 2-thiooxazolidine-2,4-dione, 2,4-oxazolidinedione, oxazolidine-
Groups such as 4-one, 2-oxazoline-4-one), thiazolidine (for example, 2-thioazoline-2,4-dione, 2,4-thiazolidinedione, thiazolidine-4-one)
Groups such as on, 2-thiazolin-4-one), imidazolidine (eg, 2-thioimidazolidin-2,4-dione, 2,4-imidazolidindione, isothiazolidin-4-one, 2-imidazolidin) -4-one and the like),
Selenazolidine-based (for example, 2-thioselenazolidine, n-
Groups such as 2,4-dione, 2,4-selenazolidinedione, selenazolidine-4-one, and 2-selenazolin-4-one).

In the general formulas (I), (IA) and (IB), Y ₂ , Z ₁ , Z ₂ , Z ₃ , Z ₄
And the 6-membered heterocyclic group formed by Z ₅
Pyridine (for example, 1,2-dihydro-2-pyridylidene, 2-pyridinium, tetrahydropyridine-2,4
-Dione, groups such as tetrahydropyridine-2,6-dione), pyrimidines (for example, tetrahydropyrimidine-
2,4-dione, tetrahydropyrimidine-2,6-dione, hexahydropyridine-2,4,6-trione,
Groups such as 2-thiohexahydropyridine-2,4,6-trione and the like, and Z pyrazoline groups (groups such as pyrazolin-5-one and pyrazolidine-3,5-dione).

In the groups substituted on these rings,
Examples of the alkyl group represented by R ₁ , R ₂ and R ₃ include straight-chain / branched unsubstituted groups such as methyl, ethyl, propyl, amyl, 2-ethylhexyl, dodecyl, 2-hexyldecyl and octadecyl. A group, a group on a ring such as cyclopentyl, cyclohexyl, or 2-carboxyethyl;
-Hydroxyethyl, 2-methanesulfonylaminoethyl, 2-methoxyethyl, 2- (2-methoxyethyl)
Examples include substituted groups such as ethyl, 2-methanesulfonylethyl, 3-sulfopropyl, and trifluoromethyl. Examples of the aryl group include phenyl, 4-t-butylphenyl, and 2,4-di-t-amyl. Phenyl, 4-
Nitrophenyl, 3-nitrophenyl, 4-methanesulfonylphenyl, 3-methanesulfonylaminophenyl, 2,4,6-trichlorophenyl, 4-trifluorophenyl, 2-methoxyphenyl, 2-acetylaminophenyl, 2- ( Substituted or unsubstituted groups such as 2-ethylureido) phenyl and the like, and examples of the heterocyclic group include 2-pyridine, 2-furyl, 2-pyrimidyl and 2-pyrimidyl.
Thienyl, 5-nitro-2-thienyl, 4-methyl-2
And substituted and unsubstituted groups such as -thiazolyl and 1-pyridinyl.

The halogen atom represented by R ₂ and R ₃ is, for example, fluorine, chlorine, bromine or iodine atom, and the alkoxy group is, for example, methoxy, ethoxy, propoxy, 2-methoxyethoxy, 2-methylthioethoxy, Examples include substituted and unsubstituted groups such as 2-methanesulfonylethoxy and 2-dodecyloxy. Examples of the aryloxy group include substituted and unsubstituted groups such as phenoxy, 2-methylphenoxy, and 4-t-butylphenoxy. Examples of each group and the heterocyclic oxy group include groups such as 1-phenyltetrazol-5-oxy and 2-tetrahydropyranyloxy, and examples of the acyloxy group include groups such as acetoxy and butanoyloxy. And
Examples of the carbamoyloxy group include each group such as acylaminooxy and N-methylcarbamoyloxy.Examples of the silyloxy group include each group such as trimethylsilyloxy and dibutylmethylsilyloxy.As the alkylthio group, For example, methylthio, octylthio, tetradecylthio, octadecylthio, 3-
There are substituted and unsubstituted groups such as phenoxypyrropropylthio and 3- (4-t-butylphenoxy) propylthio. Examples of the arylthio group include phenylthio, 2-butoxy-5-t-octylphenylthio, and 3-pentane. Examples of such groups include decylphenylthio, 2-carboxyphenylthio, and 4-tetradecanamidophenylthio. Examples of the heterocyclic thio group include 2-pentazothiazolylthio and 2,4-diphenoxy-1,3,3. Examples include groups such as 5-triazole-6-thio and 2-pyridylthio. Examples of the acylamino group include groups such as acetamido, butanamide, and benzamide. Examples of the amino group include amino, anilino, and 2-amino. Hydroxyanilino, 2-mercaptoanilino, N-acetylanilino,
There are various groups such as methylamino, N, N-diethylamino, and the ureido group is, for example, 2-phenylureido, 2
-Methylureido, 2,2-dibutylureido and the like. Examples of the sulfamoylamino group include N, N-dipropylsulfamoylamino and N-methyl-N-decylsulfamoylamino. Examples of the sulfonamide group include methanesulfonamide, butanesulfonamide, hexanesulfonamide, benzenesulfonamide, p-toluenesulfonamide, and 2-methylthio-5-hydroxybenzenesulfonamide. And as the alkoxycarbonylamino group, for example, methoxycarbonylamino,
There are various groups such as butoxycarbonylamino. Examples of the aryloxycarbonylamino group include groups such as phenoxycarbonylamino. Examples of the carbamoyl group include N-ethylcarbamoyl, N, N-dibutylcarbamoyl, and N- ( Each group includes 2-methoxyethyl) carbamoyl and N, N-dimethylcarbamoyl. Examples of the sulfamoyl group include N-ethylsulfamoyl, N, N-dipropylsulfamoyl, and N, N-dipropylsulfamoyl.
Examples of each group include N-dimethylsulfamoyl and the like; examples of the sulfonyl group include groups such as methanesulfonyl, butanesulfonyl, benzenesulfonyl, and p-toluenesulfonyl; examples of the sulfinyl group include ethanesulfinyl; There are various groups such as 3-phenoxypropylsulfinyl, and examples of the phosphonyl group include groups such as phenoxyphosphonyl, ethoxyphosphonyl, and phenylphosphonyl.Examples of the alkoxycarbonyl group include methoxycarbonyl and butoxycarbonyl. Examples of the aryloxycarbonyl group include groups such as phenoxycarbonyl and p-anisidyl. Examples of the acyl group include an acetyl group, 3-carboxypropanoyl, benzoyl, and p
And each group such as N-succinimide, N-phthalimide, and 3-allylsuccinimide.

As the compound represented by the general formula (I), a compound represented by the following general formula [Ia] or [Ib] is preferably used.

[0055] In formula (Ia) _{[Au m '(L) n'} (X) p ' ] _q general formula [Ib] _{H r' Au (L) (} X) formula, L, X and q each, It is the same as defined in general formula [I]. r 'is an integer of 1 or 2, and r' is 2 when X is a divalent group. m 'is an integer of 1 or 2; n' is an integer of 1, 2 or 3;
Alternatively, an integer of 1 satisfies the relationship m + p = n.

Specific examples of the compound represented by the formula (I) are shown below, but the present invention is not limited to these.

[0057]

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[0058]

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[0059]

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[0060]

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The organic gold compound used in the present invention can be synthesized by a known method. For example, Bull. Che
m. Japan, (1975) 48 (3), 1024-
9, J.I. Inorg. nucl. Chem, Vol. 3
8 (1), 7-11 (1976), Transitio
n Met. Chem, Vol. 2 (6), 224-2
27 (1977) and JP-A-1-147537.

Next, the organic gold compound represented by the general formula (II) will be described in detail.

When E and G are aliphatic groups, they are saturated or unsaturated, linear, branched or cyclic aliphatic hydrocarbon groups, preferably alkyl groups having 1 to 22 carbon atoms, Is an alkenyl group or an alkynyl group of 2 to 22,
These may have a substituent. Examples of the alkyl group include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, 2-ethylhexyl, decyl, dodecyl, hexadecyl, octadecyl, cyclohexyl, isopropyl, and t-butyl. Examples of the alkenyl group include allyl and butenyl.

The aromatic groups of E and G include monocyclic or condensed ring aromatic groups, and preferably have 6 to 2 carbon atoms.
0, for example, phenyl and naphthele.
These may be substituted.

The heterocyclic group of E and G is a 3- to 15-membered ring having at least one element selected from nitrogen, oxygen, sulfur, selenium and tellurium and having at least one carbon atom. And preferably a 3- to 6-membered ring, for example, pyrrolidine, piperidine, pyridine, tetrahydrofuran, thiophene, oxazal, thiazole, imidazole, benzothiazole, benzoxazole, benzimidal, selenazole, benzoselenazole, tellurazole, triazole, benzotriazole , A tetrazole, an oxadiazole, and a thiadiazole ring.

Examples of the substituents for E and G include, for example, an alkyl group (eg, methyl, ethyl, hexyl), an alkoxy group (eg, methoxy, ethoxy, octyl), an aryl group, eg, phenyl, naphthyl, tolyl, a hydroxy group , A halogen atom (eg, fluorine, chlorine, bromine, iodine), an aryloxy group (eg, phenoxy), an alkylthio group (eg, methylthio, butylthio), an arylthio group (eg, phenylthio), an acyl group (eg, acetyl, propionyl, butyryl) , Valeryl),
Sulfonyl group (eg, methylsulfonyl, phenylsulfonyl), acylamino group (eg, acetylamino, benzoylamino), sulfonylamino group (eg, methanesulfonylamino, benzenesulfonylamino), acyloxy group (eg, acetoxy, benzoxy), carboxyl group, a cyano group, a sulfo group, an amino group, _-SO 2 SM group (M represents a monovalent cation), -
SO ₂ R ¹ group can be mentioned.

Preferred as M is a metal ion or an organic cation. Examples of the metal ion include a lithium ion, a sodium ion, and a potassium ion. Examples of the organic cation include an ammonium ion (ammonium, tetramethylammonium, tetrabutylammonium, etc.), a phosphonium ion (tetraphenylphosphonium), and a guanidyl group.

Hereinafter, specific examples of the compound represented by formula (II) are shown, but the present invention is not limited to these.

[0069]

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[0070]

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[0071]

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[0072]

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[0073]

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[0074]

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[0075]

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For the method of synthesizing the above-mentioned organic gold compound and the like according to the present invention, reference is made to US Pat. No. 5,686,236.

Examples of the organic gold compounds other than the organic gold compounds represented by the general formulas (I) and (II) used in the present invention include JP-A-4-268550 and JP-A-6-11.
No. 788, Japanese Patent Publication No. 44-15748, and the like. Specific examples include the following gold compounds, which are merely examples.

[0078]

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The organic gold compound used in the present invention is preferably dissolved in a water-miscible solvent such as water, methanol, ethanol or fluorinated alcohol, alone or in a mixed solvent, and added to the silver halide grain emulsion. The gold compound used in the present invention may be added at any time during the emulsion production process, but is preferably added at the start of chemical ripening, in the middle, or immediately before the end. The addition amount is not uniform depending on the type of silver halide emulsion, the type of gold compound, ripening conditions and the like, but is usually from 1 × 10 ⁻⁴ mol to 1 × 10 ⁴ mol per mol of silver halide.
⁻⁸ mol, more preferably 1 × 10 ⁻⁵ mol to 1 mol
× 10 ⁻⁸ mol.

Next, the compounds represented by formulas (III) and (IV) of the present invention will be described.

In the general formulas (III) and (IV), (A ₁ )
(A ₁ ) ′ represents —SO ₃ M or —COOM, M represents a hydrogen atom,
It represents a metal atom (for example, a transition metal capable of forming a bond with sulfur or selenium such as alkali metal, silver, gold, and palladium), or a quaternary ammonium group or a phosphonium group. The structures of (A ₁ ) and (A ₁ ) ′ may be the same or different. Here, m is an integer of 1 to 10.

(A ₂ ) and (A ₂ ) ′ are electron-withdrawing groups (for example,
Fluorine atom, a trifluoromethyl group, a cyano group, a nitro group, -SOCF ₃ group, -SO ₂ NH ₂ group, -SO ₂ CH ₃ group and the like are preferred) represents, of (A ₂₎ and (A ₂₎ ' The structure may be the same or different. Note that n is an integer of 1 to 10.

(A ₃ ) and (A ₃ ) ′ represent a functional group containing a sulfur or selenium atom capable of binding to a silver ion (for example, a mercapto group, a thione group, a —SeH group, and a ＳSe group are preferable). , (A ₃ ) and (A ₃ ) ′ may have the same or different structures. Note that r represents 1 or 2.

Y is an aliphatic hydrocarbon (for example, having 4 carbon atoms)
It represents an aliphatic hydrocarbon of 20 to 20 or less, or an aromatic hydrocarbon (for example, a benzene ring, a naphthalene ring or the like is preferable).

X represents a sulfur or selenium atom.

In addition to the substituents such as (A ₁ ), (A ₁ ) ′, (A ₂ ), (A ₂ ) ′, (A ₃ ), (A ₃ ) ′, the following substituents You may have. That is, a halogen atom other than fluorine, a hydroxyl group, an amino group, an acylamino group, an alkylamino group, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkoxy group, an aryloxy group, an alkylthio group, an alkoxycarbonyl group, and a carbamoyl group , An alkoxyalkyl group, an aminoalkyl group, an acylaminoalkyl group, a hydroxyalkyl group, a carboxyalkyl group, a sulfoalkyl group, and an alkylsulfonamide group.

These compounds were obtained from the Journal of the Chemical Society (C) (J. Chem. So
c. Sect. C), p. 626, 1965, ibid., 1
347, 1971, Journal of Organic Chemistry (J. Org. Chem.), 34
Volume, 534 pages, 1969, JP-A-60-184057.
And the method described in JP-A-60-204742 or a method analogous thereto. Some compounds are commercially available as chemical reagents.

Specific examples of the compounds represented by formulas (III) and (IV) of the present invention are shown below, but the present invention is not limited to these.

[0089]

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[0090]

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[0091]

Embedded image The compounds represented by the general formulas (III) and (IV) may be added at any time during chemical ripening. If added before the completion of chemical ripening, the effect may be high, but if added separately before and after the completion, the effect may be further enhanced.

The compounds may be used in combination of two or more kinds, or may be used in combination with other inhibitors. As an addition method, the powder may be added as it is, or a solution dissolved in a low-boiling organic solvent such as methanol, ethanol, or ethyl acetate or water or a mixed solvent of a low-boiling organic solvent and water may be added. I do not care. At this time, if necessary, a regulator for changing the pH may be used to enhance the solubility. Further, when added as an added particulate solid dispersion, an even higher effect may be obtained. In any case, the addition amount is 0.01 g to 0.5 g per mol of silver, and preferably 0.1 g to 0.5 g.
It is from 0.2 g to 0.2 g.

In the present invention, both sulfur sensitization and gold sensitization may be performed simultaneously, or separately and stepwise. In the latter case, after moderately applying sulfur sensitization,
Alternatively, if gold sensitization is performed during the process, a favorable result may be obtained.

In the present invention, selenium sensitization can be used in combination, and a wide variety of selenium compounds can be used as the selenium sensitizer.

Useful selenium sensitizers include colloidal selenium metal, isoselenocyanates (eg, allyl isoselenocyanate, etc.), and selenoureas (eg, N, N-dimethylselenourea, N, N, N'-triethylseleno). Urea, N, N, N'-trimethyl-N'-heptafluoroselenourea, N, N, N'-trimethyl-N'-heptafluoropropylcarbonylselenourea, N, N, N '
-Trimethyl-N'-4-nitrophenylcarbonylselenourea, etc.), selenoketones (eg, selenoacetone, selenoacetophenone, etc.), selenoamides (eg, selenoacetamide, N, N-dimethylselenobenzamide, etc.), selenocarboxylic acids and Selenoesters (eg, 2-selenopropionic acid, methyl-3-selenobutyrate, etc.), selenophosphates (eg, tri-p-triselenophosphate, etc.), selenides (triphenylphosphine selenide, diethylselena And diethyl diselenide). Particularly preferred selenium sensitizers are selenoureas, selenamides and selenoketones, selenides.

The amount of the selenium sensitizer to be used varies depending on the selenium compound used, silver halide grains, chemical ripening conditions and the like, but is generally 10 ^-8 to 10 ^-4 per mol of silver halide.
Use about moles. Depending on the properties of the selenium compound to be used, the addition may be carried out by dissolving in water or an organic solvent such as methanol or ethanol alone or in a mixed solvent. Further, a method in which the mixture is added in advance with a gelatin solution, or a method in which the mixture is added in the form of an emulsified dispersion of a mixed solution with a polymer soluble in an organic solvent by the method disclosed in JP-A-4-140739 may be used.

The temperature of chemical ripening using a selenium sensitizer is 4
The range is preferably from 0 to 90 ° C, more preferably from 45 ° C to 80 ° C. The pH is 4-9 and the pAg is 6
The range of -9.5 is preferred.

Examples of tellurium sensitizers useful as tellurium sensitization methods include telluroureas (eg, N, N-dimethyltellurourea, tetramethyltellurourea, N-carboxyethyl-N, N'-dimethyltellurourea). , N, N'-dimethyl-N'-phenyltellurourea), phosphine tellurides (for example, tributylphosphine telluride, tricyclohexylphosphine telluride, triisopropylphosphine telluride, butyl-diisopropylphosphine telluride, dibutylphenylphosphine telluride) Lido), telluroamides (for example, telluroacetamide, N, N-dimethyltellurobenzamide), telluroketones, telluroesters, and isotellurocyanates.
The technology for using the tellurium sensitizer is the same as the technology for using the selenium sensitizer.

In the present invention, so-called reduction sensitization can be carried out inside the grains by setting the atmosphere in an appropriate reducing atmosphere. Preferred examples of the reducing agent include, for example, thiourea dioxide, ascorbic acid and derivatives thereof. Other preferable reducing agents include hydrazine, polyamines such as ethylenetriamine, dimethylamine borane, sulfite and the like. The amounts of these added are preferably changed depending on the type of reduction sensitizer, the particle size of silver halide grains, the composition and crystal habit, the temperature of the reaction system, the pH, and the environmental conditions such as pAg. In this case, a preferable result can be obtained by using about 0.01 to 2 mg per mol of silver halide as a rough guide. In the case of ascorbic acid, the range is preferably about 50 mg to 2 g per mol of silver halide.

The conditions for reduction sensitization are as follows:
0 ° C., time is about 10 to 200 minutes, pH is about 5 to 11, p
Ag is preferably in the range of about 1 to 10 (here, pAg
The value is the reciprocal of the Ag ⁺ ion concentration).

In the present invention, so-called silver ripening, which is a kind of reduction sensitization technique, is performed by adding a water-soluble silver salt.
The pAg at the time of silver ripening is suitably from 1 to 6, preferably from 2 to 6.
~ 4. Conditions such as temperature, pH, and time are preferably in the above-described reduction sensitization condition range. As a stabilizer for a silver halide photographic emulsion containing silver halide grains subjected to reduction sensitization, the following general stabilizers can be used, and the stabilizer disclosed in JP-A-57-82831 can be used. Inhibitors and / or V.I. S. Gahler's paper [Zeitsh
lift fur wissenschaftlich
e Photographie Bd. 63, 133
(1969)] and the use of thiosulfonic acids described in JP-A-54-1019 often give good results. These compounds may be added at any stage of the emulsion production process from the crystal growth to the preparation process immediately before coating.

In the present invention, the organic silver salt is a reducible silver source, and a silver salt of an organic acid or a heteroorganic acid containing a reducible silver ion source, especially a long chain (10 to 3 carbon atoms).
An aliphatic carboxylic acid having 0, preferably 15 to 25 carbon atoms, and a nitrogen-containing heterocyclic ring are preferred.

Organic or inorganic silver salt complexes wherein the ligand has a total stability constant for silver ions of 4.0 to 10.0 are also useful.

Examples of suitable silver salts include Research D
No. 17029 and 29996, and include: salts of organic acids, such as salts of gallic acid, oxalic acid, behenic acid, stearic acid, palmitic acid, lauric acid, etc .; silver carboxyalkylthio Urea salts (eg, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc.); silver of a polymer reaction product of an aldehyde and a hydroxy-substituted aromatic carboxylic acid Complexes (e.g., aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.), hydroxy-substituted acids (e.g., salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodisalicylic acid), silver salts of thioenes or Complex (for example, 3- (2-carboxyethyl) -4
-Hydroxymethyl-4- (thiazoline-2-thioene and 3-carboxymethyl-4-thiazoline-2-
Thioene), imidazole, pyrazole, urazole,
1,2,4-thiazole and 1H-tetrazole, 3-
Complexes or salts of silver and a nitrogen acid selected from amino-5-benzylthio-1,2,4-triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides.

In the present invention, a particularly preferred silver source is silver behenate.

The organic silver salt compound can be obtained by mixing a water-soluble silver compound and a compound which forms a complex with silver, and includes a forward mixing method, a reverse mixing method, a simultaneous mixing method, and a method described in JP-A-9-12764.
A controlled double jet method as described in No. 3 is preferably used.

In the present invention, the organic silver salt preferably has an average particle size of 1 μm or less and is monodispersed. The average particle size of the organic silver salt means that the particles of the organic silver salt are, for example, spherical,
In the case of rod-shaped or tabular grains, it refers to the diameter of a sphere equivalent to the volume of the organic silver salt grains. The average particle size is preferably 0.01 μm to 0.8 μm, particularly 0.05 μm.
m to 0.5 μm is preferred. Monodispersion has the same meaning as in the case of silver halide grains, and the preferred degree of monodispersion is 1 to 5.
30. In the present invention, the organic silver salt has an average particle size of 1
It is more preferable that the particles are monodisperse particles having a particle size of not more than μm.

In the present invention, in order to obtain a predetermined optical transmission density, the total amount of silver halide and organic silver salt is preferably from 0.3 g to 1.5 g per m ² in terms of silver. preferable. By setting it in this range, a high-contrast image can be obtained.

The amount of silver halide relative to the total amount of silver is
The weight ratio is 50% or less, preferably 25% or less, more preferably 0.1% to 15%.

The photothermographic material of the present invention preferably contains a reducing agent. Examples of suitable reducing agents are described in U.S. Patent Nos. 3,770,448, 3,773,512,
No. 3,593,863 and Research D
No. 17029 and 29996, and include the following:

Aminohydroxycycloalkenonone compounds (eg, 2-hydroxypiperidino-2-cyclohexenone); aminoreductones esters (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents An N-hydroxyurea derivative (for example, Np-methylphenyl-N
Hydrazones of aldehydes or ketones (e.g. anthracene aldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (e.g.
Hydroquinone, t-butyl-hydroquinone, isopropylhydroquinone and (2,5-dihydroxy-phenyl) methylsulfone); sulfhydroxamic acids (eg, benzenesulfhydroxamic acid); sulfonamidoanilines (eg, 4- (N- Methanesulfonamido) aniline); 2-tetrazolylthiohydroquinones (eg, 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (eg, 1,2,3,4-tetrahydro) Aminooxins; Azines (eg, a combination of an aliphatic carboxylic acid arylhydrazide and ascorbic acid); a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine; Hydroxanoic acids Combinations of azines and sulfonamidophenols; α-cyanophenylacetic acid derivatives; combinations of bis-β-naphthol and 1,3-dihydroxybenzene derivatives; 5-pyrazolones; sulfonamidophenol reducing agents; 2-phenylindane-1 ,
3-dione and the like; chroman; 1,4-dihydropyridines (eg, 2,6-dimethoxy-3,5-dicarbethoxy-1,4-dihydropyridine); bisphenols (eg, bis (2-hydroxy-3- t-butyl-5
-Methylphenyl) methane, bis (6-hydroxy-m
-Tri) mesitol, 2,2-bis (4-hydroxy-3-methylphenyl) propane,
4,5-ethylidene-bis (2-t-butyl-6-methyl) phenol), ultraviolet-sensitive ascorbic acid derivatives and 3-pyrazolidones.

Among them, particularly preferred reducing agents are hindered phenols.

The hindered phenols include compounds represented by the following general formula (A).

[0114]

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In the formula, R is a hydrogen atom or a group having 1 to 1 carbon atoms.
10 alkyl group _(e.g., -C ₄ H _9, 2,4,4-
R ′ and R ″ represent an alkyl group having 1 to 5 carbon atoms (eg, methyl, ethyl, t-
Butyl).

Specific examples of the compound represented by formula (A) are shown below. However, the present invention is not limited to the following compounds.

[0117]

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[0118]

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The amount of the reducing agent such as the compound represented by the above general formula (A) is preferably 1 × per mole of silver.
10 ^-2 to 10 mol, particularly preferably 1 × 10 ^{-2 to} 1.5
Is a mole.

Binders suitable for the photothermographic material of the present invention are transparent or translucent and generally colorless, and include natural polymer synthetic resins, polymers and copolymers, and other film-forming media such as gelatin, gum arabic,
Poly (vinyl alcohol), hydroxyethyl cellulose, cellulose acetate, cellulose acetate butyrate, poly (vinyl pyrrolidone), casein, starch, poly (acrylic acid), poly (methyl methacrylic acid), poly (vinyl chloride), poly (methacrylic acid) ), Copoly (styrene-maleic anhydride), copoly (styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal) s (eg, poly (vinyl formal) and poly (vinyl butyral)), poly (ester) ), Poly (urethane), phenoxy resin, poly (vinylidene chloride), poly (epoxide),
Poly (carbonate) s, poly (vinyl acetate),
There are cellulose esters and poly (amides). These may be hydrophilic or non-hydrophilic.

In the present invention, the binder amount of the photosensitive layer is preferably 1.5 to 10 for the purpose of preventing dimensional fluctuation after thermal development.
g / m ² , more preferably 1.
It is 7 to 8 g / m ² . If it is less than 1.5 g / m ² , the density of the unexposed portion will increase significantly and may not be usable.

In the present invention, a matting agent is preferably contained on the photosensitive layer side. In order to prevent damage to the image after thermal development, it is preferable to provide a matting agent on the surface of the photosensitive material. The matting agent is preferably contained in a weight ratio of 0.5 to 10% with respect to all binders on the emulsion layer side.

The material of the matting agent used in the present invention may be either an organic substance or an inorganic substance. For example, as inorganic substances, silica described in Swiss Patent No. 330,158, glass powder described in French Patent No. 1,296,995, etc., and alkali described in British Patent No. 1,173,181 etc. An earth metal or a carbonate such as cadmium or zinc can be used as a matting agent.

As the organic substance, US Pat. No. 2,322,
037 etc., Belgian Patent No. 625, 45
No. 1 and British Patent Nos. 981, 198, etc., polyvinyl alcohol described in JP-B-44-3643, etc., polystyrene or polymethacrylate described in Swiss Patent No. 330,158, U.S. Pat. Organic matting agents such as polyacrylonitrile described in 3,079,257 and the like and polycarbonate described in U.S. Pat. No. 3,022,169 can be used.

The shape of the matting agent may be either regular or irregular, but is preferably regular and spherical.

The size of the matting agent is represented by a diameter when the volume of the matting agent is converted into a spherical shape. In the present invention, the particle diameter of the matting agent indicates the diameter converted into a sphere. The matting agent used in the present invention preferably has an average particle size of 0.5 μm to 10 μm, more preferably 1.0 μm to 8.0 μm. The variation coefficient of the particle size distribution is preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the variation coefficient of the particle size distribution is a value represented by the following equation.

(Standard deviation of particle size) / (average value of particle size) × 100 The matting agent according to the present invention can be contained in any constituent layer, but is preferably used to achieve the object of the present invention. Is a constituent layer other than the photosensitive layer, and is more preferably the outermost layer as viewed from the support.

The method for adding the matting agent according to the present invention may be a method in which the matting agent is dispersed in a coating solution in advance and applied.
A method of spraying a matting agent after the application liquid is applied and before the drying is completed may be used. When a plurality of types of matting agents are added, both methods may be used in combination.

The photothermographic material of the present invention, which forms a photographic image by a heat development process, comprises a reducible silver source (organic silver salt), a catalytically active amount of silver halide, a hydrazine derivative,
The photothermographic material preferably contains a reducing agent and, if necessary, a color tone agent for suppressing the color tone of silver in a state of being usually dispersed in an (organic) binder matrix.

The photothermographic material of the present invention is stable at room temperature, but is developed by heating to a high temperature (for example, 80 ° C. to 250 ° C.) after exposure. Heating produces silver through an oxidation-reduction reaction between an organic silver salt (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is accelerated by the catalytic action of the latent image generated on the silver halide upon exposure. Silver produced by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas,
An image is formed. This reaction process proceeds without supplying a processing liquid such as water from the outside.

The photothermographic material of the present invention has at least one photosensitive layer on a support. Although only a photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer on the photosensitive layer.

In order to control the amount or wavelength distribution of light passing through the photosensitive layer, a filter layer may be formed on the same side as or opposite to the photosensitive layer, or a dye or pigment may be contained in the photosensitive layer. May be. As the dye, the compounds described in Japanese Patent Application No. 7-11184 are preferred.

The photosensitive layer may be composed of a plurality of layers, and the sensitivity may be changed to a high-sensitivity layer / low-sensitivity layer or a low-sensitivity layer / high-sensitivity layer in order to adjust the gradation.

Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and the other forming layers.

In the photothermographic material of the present invention, for example, a surfactant, an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, a coating aid and the like may be used.

It is preferable to add a color tone agent to the photothermographic material of the present invention. An example of a suitable toning agent is Resea
rc Disclosure No. 17029, which includes:

Imides (for example, phthalimide); cyclic imides, pyrazolin-5-ones and quinazolinones (for example, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2 , 4-thiazolidinedione); naphthalimides (eg, N-hydroxy-1,8-naphthalimide); cobalt complexes (eg, hexamine trifluoroacetate of cobalt), mercaptans (eg, 3
-Mercapto-1,2,4-triazole); N- (aminomethyl) aryldicarboximides (for example,
N- (dimethylaminomethyl) phthalimide); blocked pyrazoles, isothiuronium (isoth
uronium) derivatives and certain photobleaching combinations (eg, N, N'-hexamethylene (1-carbamoyl-3,5-dimethylpyrazole), 1,8-
A combination of (3,6-dioxaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) benzothiazole; a merocyanine dye (e.g., 3-ethyl-5-((3-ethyl -2-benzothiazolinylidene (benzothiazolinylidene))-1-methylethylidene) -2-thio-2,4
-Oxazolidinedione); phthalazinone, a phthalazinone derivative or a metal salt of these derivatives (for example, 4-
(1-naphthyl) phthalazinone, 6-chlorophthalazinone, 5,7-dimethyloxyphthalazinone, and 2,3
-Dihydro-1,4-phthalazinedione); a combination of phthalazinone and a sulfinic acid derivative (for example, 6-chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); phthalazine + phthalate Acid combinations; phthalazine (including phthalazine adducts) and maleic anhydride,
And phthalic acid, 2,3-naphthalenedicarboxylic acid or o
At least one selected from phenylene acid derivatives and anhydrides thereof (for example, phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride);
Quinazolinediones, benzoxazines, naloxazine derivatives; benzoxazine-2,4-diones (eg, 1,3-benzoxazine-2,4-dione); pyrimidines and asymmetric triazines (E.g., 2,4-dihydroxypyrimidine) and tetraazapentalene derivatives (e.g., 3,
6-dimercapto-1,4-diphenyl-1H, 4H-
2,3a, 5,6a-tetraazapentalene). Preferred toning agents are phthalazone or phthalazine.

The photothermographic material of the present invention may contain an antifoggant. What is known as the most effective antifoggant is mercury ion. Regarding the use of mercury compounds as antifoggants in photosensitive materials,
For example, it is disclosed in U.S. Pat. No. 3,589,903. However, mercury compounds are environmentally unfriendly. Non-mercury antifoggants include, for example, U.S. Pat.
No. 075 and 4,452,885 and JP-A-59
Preferred are antifoggants as disclosed in US Pat.

Particularly preferred non-mercury antifoggants are described in US Pat. Nos. 3,874,946 and 4,756,99.
No. 9, compound -C (X ₁ ) (X
₂ ) 1 represented by (X ₃ ), wherein X ₁ and X ₂ are halogen atoms, and X ₃ is hydrogen or a halogen atom.
It is a heterocyclic compound having the above substituent. As examples of suitable antifoggants, compounds described in paragraphs [0062] to [0063] of JP-A-9-90550 are preferably used.

Further, more suitable antifoggants are disclosed in US Pat. No. 5,028,523 and British Patent Application No. 92221.
No. 383.4, No. 9300147.7, No. 931
No. 1790.1.

The photothermographic materials of the present invention include, for example, JP-A-63-159814, JP-A-60-140335, JP-A-63-231437, JP-A-63-259651, and JP-A-6-259561.
3-304242, 63-15245, U.S. Pat. Nos. 4,639,414 and 4,740,455,
Nos. 4,741,966 and 4,751,175
No. 4,835,096. Useful sensitizing dyes for use in the present invention include, for example, Research Disclosure Item
Section 17643 IV-A (p. 23, December 1978),
Item 1831X (August 1978, p. 437)
Or cited in the literature cited. In particular, a sensitizing dye having a spectral sensitivity suitable for the spectral characteristics of various scanner light sources can be advantageously selected. For example, JP-A-9-34078, JP-A-9-54409, and JP-A-9-80
No. 679 is preferably used.

The support used in the present invention may be formed of a plastic film (for example, polyethylene terephthalate, polycarbonate, polyimide, nylon, cellulose, etc.) in order to obtain a predetermined optical density after development and to prevent deformation of the image after development. Triacetate, polyethylene naphthalate).

Among them, a preferred support is a support made of polyethylene terephthalate (hereinafter abbreviated as PET) and a plastic (hereinafter abbreviated as SPS) containing a styrene polymer having a syndiotactic structure.

The thickness of the support is preferably about 50 to 300 μm, more preferably 70 to 180 μm.

A plastic support which has been heat-treated can also be used. The plastics to be employed include the above-mentioned plastics. The heat treatment of the support means that after forming these supports and before the photosensitive layer is applied, at a temperature higher than the glass transition point of the support by 30 ° C. or more,
Preferably at a temperature higher than 35 ° C., more preferably 40 ° C.
Heating at a temperature higher than ℃. However, the effect of the present invention cannot be obtained by heating at a temperature exceeding the melting point of the support.

Next, the plastic used will be described.

In PET, all the polyester components are made of polyethylene terephthalate. In addition to polyethylene terephthalate, terephthalic acid, naphthalene-2,6-dicarboxylic acid, isophthalic acid, butylene dicarboxylic acid, 5-sodium Polyesters containing modified polyester components such as sulfoisophthalic acid, adipic acid, etc., and glycol components such as ethylene glycol, propylene glycol, butanediol, cyclohexane dimethanol, etc. in an amount of 10 mol% or less of the total polyester may be used.

SPS is polystyrene having steric regularity unlike ordinary polystyrene (atactic polystyrene). The regular stereoregular structure part of SPS is called a racemo chain, and it is preferable that there are more regular parts such as two, three, five or more. In the present invention, the racemo chain is 2 It is preferably 85% or more in the chain, 75% or more in the three chains, 50% or more in the five chains, and 30% or more in the further chains. The polymerization of SPS can be carried out according to the method described in JP-A-3-131843.

As the method for forming a film and the method for producing an undercoat according to the present invention, known methods can be used. Preferably, paragraphs [0030] to [0] of JP-A No. 9-50094 are used.
070].

In the image recording method of the present invention, the above-mentioned photothermographic material is written by exposure for 10 ^-2 seconds or less (hereinafter, referred to as short exposure if necessary), and the developing temperature is 80 ° C.
It is preferred to heat at a temperature of not more than ° C.

Light sources for short exposure include a glow lamp, a xenon lamp, a mercury lamp, a light emitting diode, and a He-N
e laser, argon laser, He-Cd laser,
Although a semiconductor laser is mentioned, a laser beam is preferable.

As an example of the method of making short exposure, He-N
With gas lasers such as e-lasers, short exposures of 10 ^-2 seconds or less can be achieved by passing the laser light through an optical component such as an AO modulator that acts as a shutter. In addition, since the semiconductor laser itself has an ON-OFF function, short exposure can be easily achieved.

In the present invention, the sensitivity is remarkably improved by short exposure of 10 ⁻² seconds or less, preferably 10 ^{−9 to} 10 ⁻⁵ seconds.

The developing method may be any type as long as it is heat development, and the heating means may be heating between a hot plate or heating by contact with the hot plate (for example, see JP-A-50-62635), a hot drum, a hot roller, Heating (for example, see Japanese Patent Publication No. 43-10791), heating by passing in hot air (for example, see Japanese Patent Application Laid-Open No. 53-32737), and passing through an inert liquid maintained at a constant temperature. Heating, or by heating along a heat source with a roller, belt, or guide member (for example,
-2546) etc. can be used.

The heating temperature is 80 ° C. or higher and 250 ° C. or lower. If the heating temperature is lower than 80 ° C., an image cannot be formed.
When the temperature exceeds 0 ° C., fogging of an image is extremely impractical.
A preferable selection range of the heating temperature is 100 ° C to 200 ° C.

[0157]

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

Example 1 [Preparation of Subbed Photographic Support] <Preparation of PET Subbed Photographic Support> A commercially available biaxially stretched heat-fixed PET film having a thickness of 100 μm was coated on both sides with 8 w / m 2. Apply a corona discharge treatment for ² minutes, apply the following undercoating coating solution a-1 on one surface to a dry film thickness of 0.8 μm, and dry to form an undercoating layer A-1. Was coated with the following undercoating coating solution b-1 so as to have a dry film thickness of 0.8 μm and dried to obtain an undercoating layer B-1.

<< Undercoat Coating Solution a-1 >> Butyl acrylate (30% by weight) t-butyl acrylate (20% by weight) Styrene (25% by weight) 2-hydroxyethyl acrylate (25% by weight) copolymer latex liquid (Solid content 30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Finished to 1 liter with water.

<< Undercoating Coating Solution b-1 >> Butyl acrylate (40% by weight) Styrene (20% by weight) Glycidyl acrylate (40% by weight) copolymer latex liquid (solid content 30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Make up to 1 liter with water.

Subsequently, the undercoat layer A-1 and the undercoat layer B-1
A corona discharge of 8 w / m ² · min is applied to the upper surface of the lower layer, and the lower layer upper layer coating solution a-2 is coated on the lower layer A-1 so as to have a dry film thickness of 0.1 μm. Sublayer B as Layer A-2
-1 is coated with the following undercoating layer coating solution b-2 having a dry film thickness of 0.
Coating was performed as a subbing upper layer B-2 having an antistatic function so as to have a thickness of 8 μm.

<< Coating Solution a-2 for Subbing Upper Layer >> Gelatin 0.4 g / m ² Weight (C-1) 0.2 g (C-2) 0.2 g (C-3) 0.1 g Silica particles ( (Average particle size: 3 μm) 0.1 g Finish to 1 liter with water.

<< Lower Coating Upper Layer Coating Solution b-2 >> (C-4) 60 g Latex liquid containing (C-5) as a component (solid content: 20%) 80 g Ammonium sulfate 0.5 g (C-6) 12 g Polyethylene glycol ( (Weight average molecular weight: 600) 6 g Finished to 1 liter with water.

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Embedded image (Heat treatment of the support) In the above-mentioned undercoat drying step of the undercoated support, the support was heated at a temperature of 140 ° C. Thereafter, it was gradually cooled.

(Preparation of Photosensitive Silver Halide Emulsion A) Water 9
After dissolving 7.5 g of inert gelatin and 10 mg of potassium bromide in 00 ml and adjusting the temperature to 35 ° C. and the pH to 3.0, 370 ml of an aqueous solution containing 74 g of silver nitrate and (98%) were added.
/ 2) An aqueous solution containing potassium bromide and potassium iodide in a molar ratio of 2/2) and the above-mentioned iridium compound (26) in a controlled double jet method while maintaining 1 × 10 ⁻⁶ mol per mol of silver at a pAg of 7.7. Added over 10 minutes. Thereafter, 4-hydroxy-6-methyl-1,3,3
a, 7-Tetrazindene 0.3 g was added, and the pH was adjusted to 5 with NaOH to obtain a cubic iodobromide having an average grain size of 0.06 μm, a variation coefficient of the projected diameter area of 8%, and a [100] face ratio of 87%. Silver particles were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant, and after desalting, 0.1 g of phenoxyethanol was added to adjust the pH to 5.9 and the pAg to 7.5 to obtain a silver halide emulsion.

Next, this silver halide emulsion was divided into equal parts,
1-ethyl as a sulfur sensitizer to the emulsion, 3- (2-thiazolyl) thiourea 5.0 × 10 ^-5 mol / mol Ag was added, further, a gold compound shown in Table 1 1.0 × 10 ^{- 6} mol /
Molar Ag was added and reacted at 55 ° C. for 60 minutes to sensitize the compound. Thereafter, the temperature of the silver halide emulsion was lowered to room temperature, and as shown in Table 1, the compound represented by the general formula (II) or (III) was added to some of the emulsions at 2 × 10 5
^A photosensitive silver halide emulsion was prepared by adding ^-4 mol / mol Ag and further adding an additive such as an antifoggant described below.

According to the method of Example 1 in JP-A-9-127463, silver behenate was prepared in the following manner.

Preparation of Na Behenate Solution 34 g of behenic acid was added to 340 ml of isopropanol for 65 days.
Dissolved at ° C. Next, while stirring, a 0.25N aqueous sodium hydroxide solution was added so as to have a pH of 8.7. At this time, about 400 ml of the sodium hydroxide aqueous solution was required.
Next, the aqueous sodium behenate solution was concentrated under reduced pressure to adjust the concentration of sodium behenate to 8.9% by weight.

Preparation of Silver Behenate A 2.94M silver nitrate solution was added to a solution of 30 g of ossein gelatin dissolved in 750 ml of distilled water, and the silver potential was adjusted to 4%.
00 mV. To this, 374 ml of the above sodium behenate solution was added at a speed of 44.6 ml / min at a temperature of 78 ° C. by using a controlled double jet method, and simultaneously a 2.94 M silver nitrate aqueous solution was supplied with a silver potential of 400 mV.
It was added so that it became. The amounts of sodium behenate and silver nitrate used at the time of addition were 0.092 mol and 0.101 mol, respectively.
Mole.

After completion of the addition, the mixture was further stirred for 30 minutes, and water-soluble salts were removed by ultrafiltration.

Preparation of Photosensitive Emulsion To this silver behenate dispersion, 0.01 mol of the above-mentioned photosensitive silver halide emulsion was added, and 100 g of a solution of polyvinyl acetate in n-butyl acetate (1.2 wt%) was further stirred.
Is gradually added to form a floc of the dispersion, water is removed, water is further washed twice and water is removed, and polyvinyl butyral (average molecular weight 3000) is used as a binder.
60 g of a 1: 2 mixed solution of 2.5 wt% of butyl acetate and isopropyl alcohol was added with stirring, and polyvinyl butyral (average molecular weight 4000) as a binder was added to the thus obtained mixture of behenic acid and silver halide. ) And isopropyl alcohol.

The following layers were sequentially formed on a PET support to prepare a sample. The drying was performed at 75 ° C. for 5 minutes.

Coating on back side: A liquid having the following composition was applied to a wet thickness of 80 μm.

Polyvinyl butyral (10% isopropanol solution) 150 ml Dye-B 70 mg Dye-C 70 mg

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Photosensitive layer surface side coating Photosensitive layer: A solution having the following composition was coated and the silver amount was 2.0 g / m2.
^2. 3.5 of polyvinyl butyral as binder
g / m ² .

Photosensitive Silver Halide Emulsion A Amount giving 3 g / m ² in terms of silver sensitizing dye-1 (0.1% DMF solution) 2 mg Antifoggant-1 (0.01% methanol solution) 3 ml Antifogging Agent-2 (1.5% methanol solution) 8 ml Antifoggant-3 (2.4% DMF solution) 5 ml Phthalazone (4.5% DMF solution) 8 ml Developer-1 (10% acetone solution) 13 ml Hardening agent H (1% methanol / DMF = 4: 1 solution) 2 ml

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Surface protective layer: A solution having the following composition was wetted to a thickness of 1
It was applied on each photosensitive layer so as to have a thickness of 00 μm. Acetone 175 ml 2-propanol 40 ml methanol 15 ml cellulose acetate 8.0 g phthalazine 1.0 g 4-methylphthalic acid 0.72 g tetrachlorophthalic acid 0.22 g tetrachlorophthalic anhydride 0.5 g matting agent (monodispersion having an average particle size of 4 μm) Silica) 2g

<< Evaluation of Photographic Performance >> Each of the above samples was exposed (10 ⁻⁷ seconds) with a laser sensitometer equipped with a 760 nm semiconductor laser, and then processed (developed) at 120 ° C. for 15 seconds to obtain a sample. The obtained image was evaluated by a densitometer. The result of the measurement is Dmin, the sensitivity (1 from Dmin).
0 (reciprocal of the ratio of the exposure meter giving a high density). Table 1 shows relative sensitivities with the sensitivity of 1 as 100.

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[Table 1]

As is clear from Table 1, the sample Nos. 2-No. No. 15 shows little change in sensitivity and Dmin due to storage aging regardless of before and after the heat development treatment, indicating that it is excellent. Compound III-4
And / or Sample No. 3 containing Compound IV-3. 8 ~
No. In No. 15, the color tone of the image was improved to a cool black tone so that it could be visually identified unexpectedly.

Example 2 (Preparation of photosensitive silver halide emulsion B) Japanese Patent Application No. 9-252
No. 077, the average particle diameter is 0.05 μm.
Was prepared. The aspect ratio was 6.0, the average iodine content of the whole grains was 0.4 mol%,
The average iodine content on the outermost surface of the grains was 2.8 mol%.

Next, this silver halide emulsion B was equally divided, and the following dye-2 and dye-3 were added to each emulsion.
1-ethyl, 3- (2-thiazolyl) thiourea is 8.0
× 10 ^-5 mol / mol Ag, and 1.6 × 10 ^-6 mol / mol Ag of the gold compound shown in Table 2 were added.
The mixture was allowed to react for 0 minutes and subjected to spectral sensitization and chemical sensitization. Then, after lowering the temperature of the silver halide emulsion to room temperature,
As shown in Table 2, a compound represented by the general formula (II) or (III) was added to some of the emulsions in an amount of 3.0 × 10 ⁻⁴ mol / mol Ag, and further additives such as an antifoggant described below were added. By the addition, a light-sensitive silver halide emulsion was prepared.

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The emulsion prepared as described above was coated and dried in the same manner as in Example 1 except that the above conditions and the coating conditions for the photosensitive layer described below were used to obtain evaluation samples.

Coating conditions on photosensitive layer side Photosensitive layer: A solution having the following composition was coated at a silver amount of 2.0 g / m 2.
^2. 3.5 of polyvinyl butyral as binder
g / m ² .

Photosensitive Silver Halide Emulsion B Amount of 3 g / m ² in terms of silver sensitizing dye-2 (0.1% DMF solution) 2 mg sensitizing dye-3 1 mg antifoggant-4 (0.01% Methanol solution) 3 ml Antifoggant-5 (1.5% methanol solution) 8 ml Antifoggant-3 (2.4% DMF solution) 5 ml Phthalazone (4.5% DMF solution) 8 ml Developer-1 (10% acetone Solution) 13 ml High contrast agent H (1% methanol / DMF = 4: 1 solution) 2 ml

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<< Evaluation of Photographic Performance >> 820 nm Diode
Example of each sample above using a laser sensitometer equipped with
Evaluation was performed in the same manner as in Example 1. The exposure time is 10^-6 In seconds
Was.

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[Table 2]

As is clear from Table 2, the sample Nos. 16-No. The sample No. 30 shows excellent changes in sensitivity and Dmin with storage aging regardless of before and after the heat development treatment, and thus is excellent.

The sample No. 23 to NO. 30 was the same as Example 1 in that the silver tone was improved.

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According to the present invention, it is possible to provide a photothermographic material having excellent long-term storage properties before and after thermal development and an image recording method.

Claims (6)

[Claims] 1. A photothermographic material containing at least a photosensitive silver salt, an organic silver salt, a reducing agent and a binder on a support, wherein said photosensitive silver is subjected to chemical sensitization in the presence of an organic gold compound. A photothermographic material, characterized in that it is a silver halide. 2. The photothermographic material according to claim 1, wherein the organic gold compound is a compound having at least one sulfur atom as an atom constituting the compound. 3. An organic gold compound represented by the following general formula (I) or (II):
3. The photothermographic material according to claim 1, wherein the photothermographic material is at least one compound represented by the formula: General formula (I) ( _Hr Au _m [L] _n [X] _p ) _q [wherein, L represents an organic compound ligand having a thione or thiol group, and X represents an anion. r is 0, 1 or 2, m is 1 or 2, p is 1, 2 or 3, p is 0, 1, 2
Alternatively, 3 and q each represent an integer of 1 to 4. General formula (II) E-SO ₂ S-Au (I) -SG wherein E and G may be the same or different and represent an aliphatic group, an aromatic group or a heterocyclic group. ] 4. The photothermographic material according to claim 1, wherein the photothermographic material contains at least one compound represented by the following general formula (III) or (IV). Embedded image [Wherein (A ₁ ) and (A ₁ ) ′ represent —SO ₃ M or —COOM, and M represents a hydrogen atom, a metal atom, an ammonium group or a phosphonium group. (A ₁ ) and (A ₁ ) ′ may be the same or different. m represents an integer of 1 to 10. (A ₂ ) and (A ₂ ) ′ represent an electron-withdrawing group and may be the same or different. n represents an integer of 1 to 10. (A ₃ ) and (A
₃ ) 'represents a functional group containing a sulfur or selenium atom capable of binding to a silver ion, and (A ₃ ) and (A ₃ )' may be the same or different. r is 1 or 2. Y represents an aliphatic hydrocarbon or an aromatic hydrocarbon, and X represents a sulfur atom or a selenium atom. ] 5. The photothermographic material according to claim 1, wherein
An image recording method, wherein writing is performed by exposure for ^-2 seconds or less, and heating is performed at a developing temperature of 80 ° C or more and 250 ° C or less. 6. The image recording method according to claim 5, wherein the light used for the exposure is a laser beam.