JPH08278592A - Heat-developable photosensitive material - Google Patents

Abstract

PURPOSE: To obtain the heat-developable photosensitive material capable of forming an image good in sharpness and easy to be seen by forming a dye layer having an absorption not below a specified value on at least one side of a support. CONSTITUTION: The dye layer of the heat-developable photosensitive material contains at least one kind of dye, preferably, 2 kinds of dyes each having an absorption of >=0.4 in the region of 750-1500nm and >=0.3 in the visible region. A preferable dye having such an absorption in 750-1500nm is embodied by the one represented by the formula in which each of Z<1> and Z<2> is an atomic group necessary to form a 5- or 6-membered N-containing optionally condensed hetero ring, such as an oxazole, isooxazole, or benzoxazole ring; each of R<1> -R<4> is a 1-10C, preferably, 1-6C alkyl group; and X<-> is an anion embodied by a halogen ion or ethyl-sulfate ion or the like.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photothermographic material,
The present invention relates to a photothermographic material having good sharpness and easy to see images.

[0002]

2. Description of the Related Art A photothermographic material for forming a photographic image by using a photothermographic processing method is disclosed, for example, in US Pat.
No. 3457075, and D.I. Morgan and B. “Thermally Processed Silver Systems” by Shely
(Imaging Processes and Materials) Neblette 8th
Edition, Sturge, V.I. Walwor
th), A. Edited by Shepp, page 2, 1969
Year). Such a photothermographic material is
It contains a reducible silver source (eg organic silver salt), a catalytically active amount of photocatalyst (eg silver halide), a toning agent controlling the color tone of silver and a reducing agent, usually dispersed in an (organic) binder matrix. ing. The photothermographic material is stable at room temperature, but it is a reducible silver source (functions as an oxidizing agent) when heated to a high temperature (for example, 80 ° C or higher) after exposure.
Silver is produced through a redox reaction between a reducing agent and a reducing agent.
This redox reaction is promoted by the catalytic action of the latent image generated by exposure. The silver produced by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas and forms an image. In recent years, in the medical field, technology has advanced with the keywords of processing simplification, speedup, and environmental friendliness. In this direction, an infrared laser (especially an electromagnetic wave having a wavelength of 750 nm or more) is used for exposure and a system for thermal development is conceivable. However, such a system is insufficient for medical use, especially in terms of sharpness and visibility of images.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photothermographic material which has good sharpness and is easy to see images.

[0004]

The above-mentioned objects have been achieved by the following means.

(1) A dye layer is provided on at least one side of a support, the dye layer has an absorption of at least 0.4 in the range of 750 nm to 1500 nm, and at least 0.03 in the visible region. A photothermographic material having the above absorption.

(2) The photothermographic material according to the above (1), which has an absorption of at least 0.03 in the visible region of 500 nm to 700 nm. Further (3) 7 of the dye layer
The photothermographic material according to (1) or (2) above, wherein the dye having an absorption of 0.4 or more in 50 nm to 1500 nm is a dye represented by the following general formula (I).

[0007]

[Chemical 4]

In the formula, Z ¹ and Z ² each represent a nonmetallic atom group necessary for forming a 5- or 6-membered nitrogen-containing heterocycle which may be condensed, and R ¹ and R ² are each an alkyl group. , An alkenyl group or an aralkyl group, R ³ and R ⁵ each represent a hydrogen atom or a group of non-metal atoms necessary for connecting to each other to form a 5- or 6-membered ring, and R ⁴ represents a hydrogen atom, an alkyl group, halogen atom, an aryl ^{group, -N (R 6) R 7} ,
R ⁸ represents —SR ⁸ or —OR ⁹ , R ⁶ represents a hydrogen atom, an alkyl group or an aryl group, R ⁷ represents an alkyl group, an aryl group, a sulfonyl group or an acyl group, and R ⁸ and R ⁹ are each an alkyl group. Alternatively, it represents an aryl group, and R ⁶ and R ⁷ may combine with each other to form a 5- or 6-membered ring. a and b each represent 0 or 1, and X ⁻ represents an anion.

(4) A photothermographic material, wherein the dye represented by the general formula (I) in (3) is a dye represented by the following general formula (II).

[0010]

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In the formula, Z ³ and Z ⁴ each represent a nonmetallic atom group necessary for forming a benzo or naphtho condensed ring, and R 3
¹⁰ and R ¹¹ each represent an alkyl group, an aralkyl group or an alkenyl group, and R ¹² and R ¹⁴ each represent a hydrogen atom or a non-metal atomic group necessary for forming a 5- or 6-membered ring by connecting with each other; ¹³ represents a hydrogen atom, an alkyl group, a halogen atom, an aryl group, —N (R ¹⁹ ) R ²⁰ , —SR ²¹ or —OR ²² , and R ¹⁹ , R ²⁰ , R ²¹ and R ²² are each an alkyl group or aryl. It represents a group, and R ¹⁹ and R ²⁰ may combine with each other to form a ring. R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸
Each represents an alkyl group, R ¹⁵ and R ¹⁶ or R ¹⁷ and R ¹⁸
May combine to form a ring. X ^- represents an anion.

(5) A photothermographic material, wherein the dye represented by the general formula (I) in (3) is a dye represented by the following general formula (III).

[0013]

[Chemical 6]

In the formula, Z ³ and Z ⁴ each represent an atom necessary for forming a benzo or naphtho condensed ring, R ¹⁰ and R ¹¹ each represent an alkyl group, an aralkyl group or an alkenyl group, and R ²³ and R ²⁴ represents an alkyl group or an aryl group, R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each represent an alkyl group, and R ¹⁵ and R ¹⁶ or R ¹⁷ and R ¹⁸ are linked to form a ring. Good. X ^- represents an anion.

(6) 500 nm to 700 nm in the dye layer
The photothermographic material of (1) to (5), wherein the dye having an absorption of at least 0.03 or more is selected from anthraquinone, azo, azomethine, indoaniline, and pyrazolotriazole dyes. .

(7) Characterized by being a mono-sheet type
The photothermographic material according to any one of (1) to (6).

(8) The photothermographic material according to any one of (1) to (7), which is for infrared laser exposure.

The dye layer in the photothermographic material of the present invention contains one or more dyes. Preferably, the two dyes have an absorption in the range of 750 nm to 1500 nm of 0.4 or more and an absorption in the visible region of 0.03 or more.

The dye having the absorption in the range of 750 nm to 1500 nm of 0.4 or more is preferably the dye represented by the general formula (I). The general formula (I) will be described.

In formula (I), the optionally condensed 5- or 6-membered nitrogen-containing heterocyclic ring represented by Z ¹ and Z ² is an oxazole ring, isoxazole ring, benzoxazole ring or naphthoxazole ring. , Thiazole ring, benzothiazole ring, naphthothiazole ring, indolenine ring, benzoindolenine ring, imidazole ring, benzimidazole ring, naphthimidazole ring, quinoline ring, pyridine ring, pyrrolopyridine ring, furopyrrole ring, etc. . A 5-membered nitrogen-containing heterocycle in which a benzene ring or a naphthalene ring is condensed is preferable, and an indolenine ring is most preferable. These rings may be substituted. As the substituent, a lower alkyl group (eg, methyl, ethyl), an alkoxy group (eg, methoxy, ethoxy), a phenoxy group (eg, unsubstituted phenoxy, p-chlorophenoxy), a carboxy group, a halogen atom (Cl, Br, F), an alkoxycarbonyl group (for example, ethoxycarbonyl), a cyano group, a nitro group, a hydroxy group and the like.

The alkyl group represented by R ¹ , R ² , R ⁴ , R ⁸ and R ⁹ has 1 to 10 carbon atoms, more preferably 1 carbon atom.
To 6 alkyl groups (eg methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl). Further, it may be substituted with a hydroxy group, a carboxy group, a halogen atom (Cl, Br) or the like. The alkyl groups represented by R ⁶ and R ⁷ include R ¹ , R ² , R ⁴ and R ⁸
And an alkyl group and an alkoxycarbonylalkyl group represented by R ⁹ (eg, methoxycarbonylmethyl, ethoxycarbonylmethyl, ethoxycarbonylethyl)
Is. Examples of the 5- or 6-membered ring formed by R ³ and R ⁵ which are linked to each other include cyclopentene and cyclohexene, and these rings have a substituent (eg, methyl,
t-butyl, phenyl).

The halogen atom represented by R ⁴ includes F, C
1 and Br. R ⁴ , R ⁶ , R ⁷ , R ⁸ and R
^The aryl group represented by ⁹ preferably has 6 to 12 carbon atoms, and examples thereof include a phenyl group and naphthyl. The aryl group may be substituted with the substituent described for the substituent which the ring of Z ¹ may have. The aralkyl group represented by R ¹ and R ² is preferably an aralkyl group having a carbon number of 7 to 12 (eg, benzyl, phenylethyl) and has a substituent (eg, methyl, alkoxy, chloro atom). May be. The alkenyl group represented by R ¹ and R ² is preferably an alkenyl group having a carbon number of 2 to 6, and examples thereof include a 2-pentenyl group, a vinyl group, an allyl group,
Examples thereof include 2-butenyl group and 1-propenyl group. The sulfonyl group represented by R ⁷ is preferably a sulfonyl group having 1 to 10 carbon atoms, for example, a mesyl group,
Examples thereof include a tosyl group, a benzenesulfonyl group and an ethanesulfonyl group. The acyl group represented by R ⁷ is 2
An acyl group having 10 to 10 carbon atoms is preferable, for example,
An acetyl group, a propionyl group, and a benzoyl group can be mentioned. R ⁶ and R ⁷ may combine with each other to form a heterocycle. Examples of the heterocycle include piperidine, morpholine, piperazine and the like, and these rings may have a substituent (eg, methyl, phenyl, ethoxycarbonyl). More preferably, R ¹ and R
² is an alkyl group, R ³ and R ⁴ are linked to form a 5- or 6-membered ring, and R ⁴ is —N (R ⁶ ) R ⁷ . More preferably, at least one of R ^{6 and} R ⁷ is a phenyl group.

[0023] X ^- include anions represented by halogen ions ^{(Cl -, Br -, I} -), p- toluenesulfonate ion, ethyl sulfate ion, PF ₆ ^-, B
F ₄ ⁻ , ClO ₄ ^{− and the} like can be mentioned.

In the present invention, the dye represented by the general formula (II) is more preferable. The general formula (II) will be described in detail. The benzo or naphtho fused ring formed by Z ³ and Z ⁴ may be substituted with the substituent described for Z ¹ . R ¹⁰ , R ¹¹ , R ¹³ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ²¹
And the alkyl group represented by R ²² has the same meaning as the alkyl group represented by R ¹ , R ² , R ⁴ , R ⁸ and R ⁹ described in the general formula (I). R ¹⁵ and R ¹⁶ , and R ¹⁷ and R ¹⁸ may be linked to each other to form a ring (for example, a cyclohexane ring).
The alkyl group represented by R ¹⁹ and R ²⁰ has the same meaning as the alkyl group represented by R ⁶ and R ⁷ in formula (I).
The alkenyl group and aralkyl group represented by R ¹⁰ and R ¹¹ are synonymous with the alkenyl group and aralkyl group of R ¹ and R ² . The aryl group represented by R ¹³ , R ¹⁹ , R ²⁰ , R ²¹ and R ²² is represented by R ⁴ , R ⁶ , R ⁷ and R ⁸ of the general formula (I).
And R ^{9 has} the same meaning as the aryl group. The halogen atom of R ^{13 has} the same meaning as the halogen atom of R ⁴ . Ring formation by R ¹⁹ and R ^{20 has the same} meaning as ring formation by R ⁶ and R ⁷ . X ^-
Has the same meaning as X ^{− in} formula (I). Preferably R ¹⁰
And R ¹¹ are each an alkyl group, R ¹² and R ¹⁴ are linked to form a 5- or 6-membered ring, and R ¹³ is a compound represented by —N (R ¹⁹ ) R ²⁰ . Particularly preferred is a compound having a phenyl group in at least one of R ^{19 and} R ²⁰ . In the present invention, the dye represented by the general formula (III) is particularly preferable.

The general formula (III) will be described in detail. The benzo or naphtho fused ring formed by Z ³ and Z ⁴ may be substituted with the substituent described for Z ¹ . R ¹⁰ , R ¹¹ , R
^The alkyl group represented by ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ has the same meaning as the alkyl group in R ¹ , R ² , R ⁴ , R ⁸ and R ⁹ described in formula (I). R ¹⁵ and R ¹⁶ , R ¹⁷ and R ¹⁸
May be linked to each other to form a ring (for example, a cyclohexane ring). The alkyl group represented by R ²³ and R ²⁴ is
It has the same meaning as the alkyl group for R ⁶ and R ⁷ described in the general formula (I). The alkenyl group and aralkyl group represented by R ¹⁰ and R ¹¹ are synonymous with the alkenyl group and aralkyl group of R ¹ and R ² . The aryl group represented by R ²³ and R ²⁴ has the same meaning as the aryl group represented by R ⁶ and R ⁷ in formula (I). Ring formation by R ²³ and R ^{24 has the same} meaning as ring formation by R ⁶ and R ⁷ . X ^- represents the general formula (I) X ^- as synonymous. More preferably, R ¹⁰ and R ¹¹ are each an alkyl group, and R ²³ and R ²⁴ are each a phenyl group. Specific examples of the dye of the present invention are shown below, but the scope of the present invention is not limited thereto.

[0026]

[Chemical 7]

[0027]

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[0028]

[Chemical 9]

[0029]

[Chemical 10]

[0030]

[Chemical 11]

[0031]

[Chemical 12]

[0032]

[Chemical 13]

[0033]

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[0034]

[Chemical 15]

The dyes of this invention are described in US Pat. No. 3,671,
It can be synthesized with reference to No. 648 or the like and the following synthesis examples. Synthesis Example (Synthesis of Compound 2) 1,2,3,3-tetramethyl-5
-Chloroindolenium-p-toluenesulfonate 11.4 g, N- (2,5-dianilinomethylenecyclopentylidene) -diphenylaluminum perchlorate 7.2 g, ethyl alcohol 100 ml, acetic anhydride 6 ml, triethylamine 12 ml Temperature 100 ℃
After stirring for 1 hour, the precipitated crystals were filtered off. Recrystallization with 100 ml of methyl alcohol gave 7.3 g of compound 2. Melting point: 270 ° C. or higher, λmax: 800.8 nm ε:
2.14 × 10 ⁵ (chloroform) Other compounds can be similarly synthesized.

The dye having absorption in the range of 750 nm to 1500 nm can be added to the dye layer near the support on the same side as the photosensitive layer and to the dye layer on the side opposite to the photosensitive layer. The dye may vary depending on the desired purpose, but 0.1 to 1000 mg so as to have an absorption of at least 0.4 in the range of 750 nm to 1500 nm.
/ M ² , preferably 1 to 200 mg / m ^{2 is} added. At least 0. 0 to 500 nm to 700 nm used in the present invention.
As the dye having an absorption of 03 or more, anthraquinone, azo, azomethine, indoaniline, and pyrazolotriazole dyes are preferably used. More preferably, it is an anthraquinone dye. 500 in the present invention
The amount of the dye having an absorption at nm to 700 nm depends on the absorption of the dye, but is 0.5 mg / m-150 mg / m ² , more preferably 1 so as to have an absorption of at least 0.03 or more. -100 mg / m ² may be used. 50 below
Specific examples of dyes having absorption at 0 nm to 700 nm are shown below.
The present invention is not limited to these.

[0037]

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[0038]

[Chemical 17]

[0039]

[Table 1]

It is preferable that any of the dyes be dissolved in an organic solvent and added. From the viewpoint of being friendly to the earth, it is preferable that the photothermographic material is such that the dye substantially remains on the image sheet to be observed. More preferred is a mono-sheet type photothermographic material (a type in which all materials provided for image formation are completed as image sheets to be observed). Further, in order to achieve the purpose, it is preferably a photothermographic material for infrared laser exposure. Further, the wavelength of infrared laser exposure is 750 nm or more, further preferably 80
The thickness is preferably 0 nm or more.

The photothermographic material of the present invention forms a photographic image using a photothermographic processing method. As such a photothermographic material, as described above, for example, US Pat.
152904, 3457075, and D.M. Morgan and B. “Thermally Processed SilverSy” by Shely
stems) "(Imaging Processes &
Materials (Imaging Processes and Materials) Neb
lette 8th Edition, Sturge, V.L. Walworth, A. Edited by Shepp, page 2,
1969) and the like.

The photothermographic material of the present invention may be any one as long as it can form a photographic image by using a photothermographic treatment, but it contains a reducible silver source (eg organic silver salt) and a catalytically active amount of photocatalyst (eg halogen). It is preferably a photothermographic material containing silver halide), a color tone controlling agent for controlling the color tone of silver, and a reducing agent in a state of being normally dispersed in an (organic) binder matrix. The photothermographic material of the present invention is stable at room temperature,
After exposure, it is developed by heating to a high temperature (for example, 80 ° C. or higher). When heated, silver is produced through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and the reducing agent. This redox reaction is promoted by the catalytic action of the latent image generated by exposure. The silver produced by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas and forms an image.

The photothermographic material of the present invention has at least one photosensitive layer on a support. Although only the photosensitive layer may be formed on the support, it is preferable to form at least one non-photosensitive layer on the photosensitive layer. A filter layer may be formed on the same side or on the opposite side of the photosensitive layer in order to control the amount of light passing through the photosensitive layer or the wavelength distribution, and a dye represented by the general formula (I) of the present application may be formed in the photosensitive layer. Other dyes or pigments may be included. The photosensitive layer may be composed of a plurality of layers, and the sensitivity may be a high sensitive layer / low sensitive layer or a low sensitive layer / high sensitive layer for adjusting gradation. Various additives may be added to any of the light-sensitive layer, non-light-sensitive layer, and other forming layers.

The support applicable to the photothermographic material of the present invention includes, for example, paper, polyethylene-coated paper, polypropylene-coated paper, parchment, cloth, etc .;
Sheets or films of metals such as aluminum, copper, magnesium, zinc; glass or chromium alloys, steel,
Glass coated with a metal such as silver, gold or platinum; poly (alkyl methacrylates) (eg poly (methyl methacrylate)), poly (esters) (eg poly (ethylene terephthalate)), poly (vinyl acetals) ), Poly (amides) (eg, nylon), and cellulose esters (eg, cellulose nitrate, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate) and the like. For 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.

Each binder layer (eg, synthetic polymer) together with the chemical agent in the photothermographic material of the present invention may form a self-supporting film. The support may be a known auxiliary material such as vinylidene chloride, an acrylic acid monomer (eg, acrylonitrile or methyl acrylate).
And unsaturated dicarboxylic acids (eg itaconic acid, acrylic acid), carboxymethylcellulose, copolymers and terpolymers of poly (acrylamide); and similar polymeric materials may be supplementarily coated.

Suitable binders are transparent or translucent, generally colorless, and include natural polymeric 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 (vinylpyrrolidone), casein, starch, poly (acrylic acid), poly (methylmethacrylic acid), poly (vinyl chloride), poly (methacrylic acid), copoly (styrene-maleic anhydride), copoly (Styrene-acrylonitrile), copoly (styrene-butadiene), poly (vinyl acetal)
(For example, poly (vinyl formal) and poly (vinyl butyral)), poly (ester) s, poly (urethane) s, phenoxy resin, poly (vinylidene chloride), poly (epoxides), poly (carbonates), There are poly (vinyl acetate), cellulose esters, and poly (amide) s. The binder may be formed by coating with water, an organic solvent or an emulsion.

The addition of toning agents is highly desirable. Examples of suitable toning agents are disclosed in Research Report 17029,
There are: imides (eg phthalimide);
Cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, succinimide, 3-phenyl-2-pyrazolin-5-one, 1-phenylurazole, quinazoline and 2,4-thiazolidinediones); naphthalimides (eg, , N-hydroxy-1,8-naphthalimide); cobalt complex (eg, hexamine trifluoroacetate of cobalt), mercaptans (eg, 3-mercapto-1,2,4-triazole); N
-(Aminomethyl) aryldicarboximides (eg N- (dimethylaminomethyl) phthalimide);
Blocked pyrazoles, isothiuronium (isot
hiuronium) derivative and certain photobleaching agents in combination (eg, N, N ′ hexamethylene (1-carbamoyl-3,5-dimethylpyrazole), 1,8- (3,6-)
A combination of dioxaoctane) bis (isothiuronium trifluoroacetate) and 2- (tribromomethylsulfonyl) benzothiazole); a merocyanine dye (for example, 3-ethyl-5-((3-ethyl-2-benzothia Zolinylidene (benzothiazolinylidene) -1
-Methylethylidene) -2-thio-2,4-oxazolidinedione); phthalazinone, phthalazinone derivatives or metal salts 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 (eg, ,
6-chlorophthalazinone + sodium benzenesulfinate or 8-methylphthalazinone + sodium p-trisulfonate); combination of phthalazine + phthalic acid; phthalazine (including adduct of phthalazine), maleic anhydride, and phthalic acid , 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivatives and their anhydrides (for example,
Phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride) in combination with at least one compound; quinazolinediones, benzoxazine, naltoxazine derivatives; benzoxazine-2,4-dione (Eg 1,3-benzoxazine-2,4-dione); pyrimidines and asymmetric-triazines (eg 2,4-dihydroxypyrimidine), and tetraazapentalene derivatives (eg
3,6-dimerocapto-1,4-diphenyl-1H, 4
H-2,3a, 5,6a-tetraazapentalene. Phthalazine is preferred as a toning agent:

[0048]

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It is As the reducing agent, so-called photographic developers such as phenidone, hydroquinones, catechol and the like may be contained, but hindered phenol is preferable. Color light-sensitive materials such as those disclosed in U.S. Pat. No. 4,460,681 are also conceivable in the realization of the present invention.

Examples of suitable reducing agents are described in US Pat. No. 3,770.
448, 3773512, 3593863, and Research Disclosure Nos. 17029 and 29.
963 and include the following: aminohydroxycycloalkenone compounds (eg, 2-hydroxy-piperidino-2-cyclohexenone); aminoreductones esters (eg, as precursors of developers) (eg, Piperidinohexose reductone monoacetate); N-hydroxyurea derivatives (eg Np-
Methylphenyl-N-hydroxyurea); aldehyde or ketone hydrazones (eg, anthracene aldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (eg, hydroquinone, t-butyl-hydroquinone) , Isopropylhydroquinone and (2,5-dihydroxy-phenyl) methyl sulfone); sulfhydroxamic acids (eg, benzenesulfhydroxamic acid); sulfonamide anilines (eg, 4- (N-
Methanesulfonamido) aniline); 2-tetrazolylthiohydroquinones (eg, 2-methyl-5- (1-
Phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (eg 1,2,3,4-
Tetrahydroquinoxaline); amidooxins; azines (for example, aliphatic carboxylic acid aryl hydrazides and ascorbic acid); polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine; hydroxanoic acids; azines and sulfones Combination of amidophenols; α-cyanophenylacetic acid derivative; bis-β-naphthol and 1,3-
Combination of dihydroxybenzene derivatives; 5-pyrazolones; sulfonamide phenol reducing agent; 2-phenylindane-1,3-dione, etc .; chromane; 1,4-dihydropyridines (eg 2,6-dimethoxy-3 , 5-dicarboethoxy-1,4-dihydropyridine); bisphenols (for example, bis (2-
Hydroxy-3-t-butyl-5-methylphenyl) methane, bis (6-hydroxy-m-tri) mesitol, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 4,4 -Ethylidene-bis (2
-T-butyl-6-methyl) phenol), UV-sensitive ascorbic acid derivatives and 3-pyrazolidones. A preferred developer is a hindered phenol of general formula (A):

[0051]

[Chemical 19]

Here; R is a hydrogen atom or a carbon atom of 1
10 alkyl group (e.g., -C ₄ H _9, 2,4,4
-Trimethylpentyl), R ⁵ and R ⁶ are alkyl groups having 1 to 5 carbon atoms (eg, methyl, ethyl, t
-Butyl).

A silver halide useful as a catalytically active amount of a photocatalyst is any photosensitive silver halide (eg, silver bromide, silver iodide, silver silver, chlorobromide, silver iodobromide, chloroiodo). However, it is preferable that the iodide ion is contained. The silver halide may be added to the imaging layer in any manner, with the silver halide being placed in close proximity to the reducible silver source. Generally it is preferred that the silver halide contain an amount of 0.75 to 30% by weight, based on the reducible silver source. The silver halide may be prepared by conversion of the silver soap portion by reaction with halogen ions, preformed and added at the time of soap formation, or a combination of these methods is possible. The latter is preferred.

The reducible silver source can be any material containing a source of reducible silver ions. Silver salts of organic and heteroorganic acids, especially long chains (10-30, preferably 15-25
Aliphatic carboxylic acids having the number of carbon atoms of 1) are preferred. Also useful are organic or inorganic silver salt complexes in which the ligand has a total stability constant for silver ions of 4.0 to 10.0. Examples of suitable silver salts are found in Research Disclosure No. 1702.
9 and 29963, including:
Salts of organic acids (eg gallic acid, oxalic acid, behenic acid,
Stearic acid, palmitic acid, lauric acid, etc.); Silver carboxyalkyl thiourea salts (for example, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea, etc.); Aldehydes Complex of a polymer reaction product of carboxylic acid with hydroxy-substituted aromatic carboxylic acid (eg, aldehydes (formaldehyde, acetaldehyde, butyraldehyde), hydroxy-substituted acids (eg, salicylic acid, benzoic acid, 3,5-
Dihydroxybenzoic acid, 5,5-thiodisalicylic acid),
Silver salts or complexes of thioenes (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-amino-5-benzylthio-1,2,4-
Complexes or salts of nitrogen acid and silver selected from triazole and benzotriazole; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides. The preferred silver source is silver behenate. The reducible silver source preferably has a silver amount of 3 g / m ² or less. It is more preferably 2 g / m ² or less.

An antifoggant may be contained in such a light-sensitive material. The most effective antifoggant was mercury ion. The use of mercury compounds as antifoggants in light-sensitive materials is described, for example, in US Pat.
No. 03. However, mercury compounds are environmentally unfavorable. As the non-mercury antifoggant, for example, the antifoggants disclosed in US Pat. Nos. 4,456,075 and 4,458,885 and Japanese Patent Publication No. 59-57234 are preferable.

Particularly preferred non-mercury antifoggants are compounds such as those disclosed in US Pat. Nos. 3,874,946 and 4,756,999, --C (X ¹ ) (X ² ) (X ³ ), where X ¹ and X ² Is a heterocyclic compound having one or more substituents represented by halogen (for example, F, Cl, Br and I) and X ³ is hydrogen or halogen). Examples of suitable antifoggants include:

[0057]

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[0058]

[Chemical 21]

Even more preferred antifoggants are US Pat. No. 5,028,523 and British Patent Application No. 9222138.
3.4, 9300147.7, 93111790.1
No.

The photothermographic material of the present invention includes, for example, JP-A Nos. 63-159841, 60-140335, 63-231437, 63-259651, and 6-63.
3-304242, 63-15245, U.S. Pat. Nos. 4,639,414, 4,740,455, and 47,419.
The sensitizing dyes described in Nos. 66, 4751175 and 4835096 can be used.

[0061]

【Example】

Example 1 Photosensitive mixture NaOH 89 g Distilled water 1500ml solution prepared solution stearate 126g behenic acid 630g of distilled water 13 liters 85 ° C. 15 minutes Emulsion A concentrated HNO ₃ 19 ml of distilled water 50ml solution AgNO ₃ 365 g Distilled water 2500ml solution of polyvinyl butyral 86 g Ethyl acetate 4300 ml solution Polyvinyl butyral 290 g Isopropanol 3580 ml solution N-Bromosuccinimide 9.7 g Acetone 690 ml

The solution was added over 5 minutes with vigorous stirring while keeping the solution at 85 ° C., and then the solution was added to 2
Add over 5 minutes. After stirring for 20 minutes, 35
Cool down to ℃. Add the solution over 5 minutes with more vigorous stirring at 35 ° C. and continue stirring for 90 minutes.
Then, the solution was added, and the mixture was left without stirring, and the aqueous phase was removed together with the salt contained therein to obtain an oil phase, which was desolvated to remove traces of water, and then the solution was added and vigorously stirred at 50 ° C. Then, the solution was added over 20 minutes and stirred for 105 minutes to obtain emulsion A.

The following layers were successively formed on a biaxially stretched 175 μ thick polyethylene terephthalate support. Drying was performed at 75 ° C. for 5 minutes.

Back side coating Antihalation layer (wet thickness 80 micron) Polyvinyl butyral (10% isopropanol solution) 150 ml Dye (solvent uses DMF, acetone or methyl chloride) Table 2

Photosensitive layer side coating Photosensitive layer (wet thickness 140 micron) Photosensitive emulsion A 73 g Sensitizing dye-1 (0.1% DMF solution) 2 ml Antifoggant-1 (0.01% methanol solution) 3 ml Fog Inhibitor-2 (0.85% methanol solution) 10 ml Anti-foggant-3 (0.85% methanol solution) 10 ml Phtharazone (4.5% DMF solution) 9 ml Reducing agent-1 (10% acetone solution) 13 ml

Surface protective layer (wet thickness 100 micron) 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 0.24 g Tetrachlorophthalic anhydride 0.5 g

[0067]

[Chemical formula 22]

Sensitometry The photothermographic material prepared above was processed into a half-cut size,
An 830 nm laser diode was exposed with a beam tilted 13 ° from the vertical. Then, using a heat drum, 1
A heat development treatment was performed at 20 ° C. for 5 seconds. Evaluation of sharpness Exposure was made to white light of 2856K with light dispersed by using an interference filter of 830 nm and processed under the above conditions, and sharpness was measured with an optical density of 1.0 and an MTF value of 15 lines / mm. evaluated.

Evaluation of Visibility of Image The heat-treated sample was visually evaluated. ◯: Clean is acceptable Δ: Dull color is anxious ×: Image is difficult to see and there is a problem

[0070]

[Table 2]

From Table 2, the sample of the present invention has no problem in the visibility of the image and has a good sharpness.

Example 2 Preparation of Photosensitive Emulsion B Solution Stearic acid 131 g Behenic acid 635 g Distilled water 13 liters 85 ° C. and mixed for 15 minutes Solution A Preformed cubic AgBrI (I = 4 mol%) 0.05 μ (as Ag) 0.22 mole) distilled water 1250ml solution NaOH 89 g distilled water 1500ml solution of concentrated HNO ₃ 19 ml of distilled water 50ml solution AgNO ₃ 365 g distilled water 2500ml solution polyvinylbutyral 86g ethyl acetate 4000ml solution polyvinylbutyral 290g isopropanol 3580ml

Solution A was added over 10 minutes with vigorous stirring while keeping the solution at 85 ° C., followed by addition of solution over 5 minutes, and then over 25 minutes. After stirring for 20 minutes as it is, the temperature is lowered to 35 ° C. Add the solution over 5 minutes with more vigorous stirring at 35 ° C. and continue stirring for 90 minutes. Then, the solution was added, and the mixture was left without stirring, and the aqueous phase was removed together with the salt contained therein to obtain an oil phase, which was desolvated to remove traces of water, and then the solution was added and vigorously stirred at 50 ° C. After 10
Emulsion B was obtained by stirring for 5 minutes.

A test was conducted in the same manner as in Example 1 except that the antihalation layer was provided below the photosensitive layer on the side of the photosensitive layer. Similar to Example 1, the sample using the dye layer of the present invention had no problem in viewability of images and had high sharpness.

[0075]

According to the present invention, the sharpness is excellent and the image is easy to see.

Claims (8)

[Claims] 1. A dye layer is provided on at least one side of a support, the dye layer has an absorption of at least 0.4 in the range of 750 nm to 1500 nm, and at least 0.03 or more in the visible region. A photothermographic material having the absorption of 2. The photothermographic material according to claim 1, which has an absorption of at least 0.03 or more in a visible region of 500 nm to 700 nm. 3. A dye layer having a density of 0.
The photothermographic material according to claim 1, wherein the dye having an absorption of 4 or more is a dye represented by the following general formula (I). Embedded image In the formula, Z ¹ and Z ² each represent a non-metal atom group necessary for forming a 5- or 6-membered nitrogen-containing heterocycle which may be condensed, and R ¹ and R ² are each an alkyl group or an alkenyl group. Or an aralkyl group, R ³ and R ⁵ each represent a hydrogen atom or a group of non-metal atoms necessary for connecting to each other to form a 5- or 6-membered ring, and R ⁴ represents a hydrogen atom, an alkyl group, a halogen atom, aryl ^{groups, -N (R 6) R 7} , represents -SR ⁸ or -OR ^9, R ⁶ is a hydrogen atom, an alkyl group or an aryl group, R ⁷ is an alkyl group, an aryl group,
It represents a sulfonyl group or an acyl group, R ⁸ and R ⁹ each represent an alkyl group or an aryl group, and R ⁶ and R ⁷ may be linked to each other to form a 5- or 6-membered ring. a and b each represent 0 or 1, and X ⁻ represents an anion. 4. The photothermographic material according to claim 3, wherein the dye represented by the general formula (I) is a dye represented by the following general formula (II). Embedded image In the formula, Z ³ and Z ⁴ each represent a non-metal atom group necessary for forming a benzo or naphtho condensed ring, R ¹⁰ and R ¹¹ each represent an alkyl group, an aralkyl group or an alkenyl group, and R ¹² and R ¹² Each ¹⁴ represents a hydrogen atom or a group of non-metal atoms necessary for forming a 5- or 6-membered ring by connecting with each other, and R ¹³ represents a hydrogen atom, an alkyl group, a halogen atom, an aryl group, -N (R ¹⁹ ) R. ²⁰ , -SR ²¹ or -OR ²² , R ¹⁹ , R ²⁰ , R ²¹ and R ²² each represent an alkyl group or an aryl group, and R ¹⁹ and R ²⁰ may be linked to each other to form a ring. . R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each represent an alkyl group, and R ¹⁵ and R ¹⁶ or R ¹⁷ and R ¹⁸ may be linked to form a ring. X ^- represents an anion. 5. The photothermographic material according to claim 3, wherein the dye represented by the general formula (I) is a dye represented by the following general formula (III). Embedded image In the formula, Z ³ and Z ⁴ each represent an atom necessary for forming a benzo or naphtho condensed ring, R ¹⁰ and R ¹¹ each represent an alkyl group, an aralkyl group or an alkenyl group, and R
²³ and R ²⁴ each represent an alkyl group or an aryl group,
R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each represent an alkyl group,
¹⁵ and R ¹⁶ or R ¹⁷ and R ¹⁸ may combine to form a ring. X ^- represents an anion. 6. The dye having an absorption of at least 0.03 at 500 nm to 700 nm in the dye layer is selected from anthraquinone, azo, azomethine, indoaniline, and pyrazolotriazole dyes. The photothermographic material according to claim 1. 7. The photothermographic material according to claim 1, which is of a monosheet type. 8. The photothermographic material according to claim 1, which is for infrared laser exposure.