JPH10123660A - Thermally developing photosensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quench the phosphor of cyanine dye and enhance the sharpness by containing a specified organic oxidizing agent and a specified dye. SOLUTION: This photosensitive material contains an organic oxidizing agent represented by the formula I and a dye represented by the formula II. In the formal I, X<1> and X<2> , which may be the same or different, each represent oxygen atom, sulfur atom, -NR<1> group or -CR<2> R<3> group, and (m) and (n) represent an integer of 0-3 as they satisfy m+n>=2, R<1> -R<3> , which may be the same or different, each represent hydrogen atom or a substituent. L<1> and L<2> , which may be the same or different, each represent a divalent connecting group. In the formula II, Z<1> and Z<2> , which may be the same or different, each represent a nonmetal atomic group necessary for forming a 5- or 6-membered nitrogenous heterocycle which may be condensed. R<4> and R<5> , which may be the same or different, each represent an alkyl group, an alkenyl group or the like, L represents a connecting group generated by connecting 5, 7 or 9 methine groups by conjugate double bond, (a), (b) and (c) each represent 0 or 1, and X represents an anion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a technique for improving sharpness of a photothermographic material.

[0002]

2. Description of the Related Art A photothermographic material for forming a photographic image using a heat development process is disclosed in, for example, US Pat. No. 3,152,904.
No. 3,457,075 and B.I. "Thermal Proceed Silver System" by Shely
ssed Silver Systems) "(Imaging Processes and Mats
erials) Neblette 8th edition, Sturge, V.E. Walworth, A .; Shepp, ed., Page 2, 1996). Such a photothermographic material comprises a reducible silver salt (for example, an organic silver salt), a catalytically active amount of a photocatalyst (for example, silver halide), a color tone controlling agent for controlling the color tone of silver, and a reducing agent which are usually (organic) binder. It is contained in a dispersed state in the matrix. The photothermographic material is stable at room temperature, but is exposed to high temperature (for example, 80
When heated to above (° C. or more), silver is generated through a redox reaction between a reducible silver source (functioning as an oxidizing agent) and a reducing agent. This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure. The silver formed by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of an image. 2. Description of the Related Art In recent years, in the medical field, technology has been advanced with the keywords of simplification and speeding up of processing and gentleness to the earth. In this direction,
A system in which exposure is performed by a near-infrared laser (in particular, an electromagnetic wave having a wavelength of 750 nm or more) and heat development is considered.
In order to improve the sharpness of an image of such a system, Japanese Patent Application No. 7-11184 uses a cyanine dye, but the sharpness is insufficient. Also EP071
No. 4,046 uses a dye in combination to improve sharpness, but is still insufficient. It is considered that the cyanine dye fluoresces and the sharpness was not sufficiently improved.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photothermographic material having excellent sharpness by quenching the fluorescence of a cyanine dye.

[0004]

The above object has been achieved by a photothermographic material containing an organic oxidant represented by the following formula (1a) and a dye represented by the following formula (2a).

[0005]

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In the formula, X ¹ and X ² may be the same or different and each represent an oxygen atom, a sulfur atom, ＝ NR ¹ group or ＣＲCR ² R ³ group, and m and n satisfy m + n ≧ 2. Represents an integer of 0 to 3 as described above. R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a substituent. L ¹ and L ² may be the same or different and represent a divalent linking group.

The general formula (1a) will be described in detail. The substituent represented by R ¹ , R ² and R ³ is a substituent bonded with a halogen atom or a carbon atom, an oxygen atom, a nitrogen atom or a sulfur atom, and is an alkyl group, an alkenyl group, an aralkyl group, an aryl group, Heterocyclic group, cyano group, nitro group, mercapto group, hydroxy group, alkoxy group, aryloxy group, alkylthio group, arylthio group, acyloxy group, amino group, alkylamino group, carboxamide group, sulfonamide group, sulfamoyl Amino group, oxycarbonylamino group, oxysulfonylamino group, ureido group, thioureido group, acyl group, oxycarbonyl group, carbamoyl group, sulfonyl group, sulfinyl group, sulfamoyl group, carboxyl group (including salt),
And a sulfo group (including a salt). These may be further substituted with these substituents.

Examples of the substituents represented by R ¹ , R ² and R ³ are shown in more detail. The alkyl group has 1 to 18 carbon atoms,
Preferably it is a linear, branched or cyclic alkyl group having 6 to 18 carbon atoms, such as methyl, ethyl, propyl, isopropyl, t-butyl, cyclopentyl, cyclohexyl, 2-hydroxyethyl, 3-hydroxypropyl, -Hydroxybutyl, 3-methoxypropyl, 2-aminoethyl, acetamidomethyl, 2-acetamidoethyl, carboxymethyl, 2-carboxyethyl, 2-sulfoethyl, ureidomethyl, 2-ureidoethyl, carbamoylmethyl, 2-carbamoylethyl, 3-carbamoylpropyl, pentyl, hexyl,
Octyl, decyl, undecyl, dodecyl, hexadecyl, octadecyl and the like can be mentioned. The alkenyl group has 2 to 18 carbon atoms, preferably 6 to 1 carbon atoms.
8 is a linear, branched or cyclic alkenyl group, for example, vinyl, allyl, 1-propenyl, 2-pentenyl, 1,3-butadienyl, 2-octenyl, 3-dodecenyl and the like.

The aralkyl group is an aralkyl group having 7 to 10 carbon atoms, such as benzyl. The aryl group is an aryl group having 6 to 10 carbon atoms, for example, phenyl, naphthyl, p-dibutylaminophenyl, p-
Methoxyphenyl and the like. The heterocyclic group forms a ring with a 5- or 6-membered saturated or unsaturated heterocyclic group composed of a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom. The number of heteroatoms and the kind of element may be one or more, for example, furyl, benzofuryl,
Pyranyl, pyrrolyl, imidazolyl, isoxazolyl, pyrazolyl, benzotriazolyl, pyridyl, pyrimidyl, pyridazinyl, thienyl, indolyl, quinolyl, phthalazinyl, quinoxalinyl, pyrrolidinyl, pyrrolinyl, imidazolidinyl, imidazolinyl, pyrazolidinyl, piperidinyl, pyridinyl, pyridinyl, piperidinyl
And morpholinyl. Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. The alkoxy group has 1 to 18 carbon atoms, preferably 6 to 1 carbon atoms.
8 alkoxy groups such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, 2-methoxyethoxy, 2-methanesulfonylethoxy, pentyloxy, hexyloxy, octyloxy, undecyloxy, dodecyloxy, hexadecyloxy, octadecyl Oxy and the like can be mentioned. As the aryloxy group, an aryloxy group having 6 to 10 carbon atoms, for example,
Phenoxy, p-methoxyphenoxy and the like can be mentioned. The alkylthio group has 1 to 18 carbon atoms, preferably 6 to 18 carbon atoms, and includes, for example, methylthio, ethylthio, octylthio, undecylthio, dodecylthio, hexadecylthio, octadecylthio and the like. The arylthio group has 6 to 10 carbon atoms.
Examples of the arylthio group include phenylthio and 4-methoxyphenylthio. The acyloxy group has 1 to 18 carbon atoms, preferably 6 to 1 carbon atoms.
8 acyloxy groups such as acetoxy, propanoyloxy, pentanoyloxy, octanoyloxy,
Dodecanoyloxy, octadecanoyloxy and the like can be mentioned.

The alkylamino group has 1 to 1 carbon atoms.
8, preferably an alkylamino group having 6 to 18 carbon atoms, such as methylamino, dimethylamino, diethylamino, dibutylamino, octylamino, dioctylamino, undecylamino and the like. The carbonamido group is a carbonamido group having 1 to 18 carbon atoms, preferably 6 to 18 carbon atoms, such as acetamido, acetylmethylamino, acetyloctylamino, acetyldecylamino, acetylundecylamino, acetyloctadecylamino, and propanoyl. Amino, pentanoylamino,
Octanoylamino, octanoylmethylamino, dodecanoylamino, dodecanoylmethylamino, octadecanoylamino and the like. The sulfonamide group is a sulfonamide group having 1 to 18 carbon atoms, preferably 6 to 18 carbon atoms, such as methanesulfonamide, ethanesulfonamide, propylsulfonamide, 2-methoxyethylsulfonamide, and 3-aminopropylsulfonamide. , 2-acetamidoethylsulfonamide, octylsulfonamide, undecylsulfonamide and the like. The oxycarbonylamino group has 1 to 1 carbon atoms.
8, preferably an oxycarbonylamino group having 8 to 18 carbon atoms, such as methoxycarbonylamino, ethoxycarbonylamino, octyloxycarbonylamino, undecyloxycarbonylamino and the like. The oxysulfonylamino group is an oxysulfonylamino group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms.
Methoxysulfonylamino, ethoxysulfonylamino, octyloxysulfonylamino, undecyloxysulfonylamino and the like. The sulfamoylamino group has 0 to 18 carbon atoms, preferably 8 to 18 carbon atoms.
In the sulfamoylamino group of, for example, methylsulfamoylamino, dimethylsulfamoylamino, ethylsulfamoylamino, propylsulfamoylamino,
Octylsulfamoylamino, undecylsulfamoylamino and the like. The ureido group has 1 to 1 carbon atoms.
18, preferably a ureido group having 8 to 18 carbon atoms, for example, ureide, methylureide, N, N-dimethylureide, octylureide, undecylureide and the like. The thioureido group is a thioureido group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, and examples thereof include thioureide, methylthioureide, N, N-dimethylthioureide, octylthioureide, and undecylthioureide. As the acyl group, an acyl group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, such as acetyl, benzoyl, octanoyl, decanoyl, undecanoyl,
Octadecanoyl and the like. The oxycarbonyl group is an oxycarbonyl group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, octyloxycarbonyl, undecyloxycarbonyl and the like. The carbamoyl group is a carbamoyl group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, such as carbamoyl, N, N-dimethylcarbamoyl, N-ethylcarbamoyl, N-octylcarbamoyl, N, N-dioctylcarbamoyl, N -Undecylcarbamoyl and the like. As the sulfonyl group, a sulfonyl group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, such as methanesulfonyl, ethanesulfonyl,
2-chloroethanesulfonyl, octanesulfonyl, undecanesulfonyl and the like. The sulfinyl group is a sulfinyl group having 1 to 18 carbon atoms, preferably 8 to 18 carbon atoms, such as methanesulfinyl, ethanesulfinyl, and octanesulfinyl. The sulfamoyl group has 0 to 18 carbon atoms, preferably 8 to 8 carbon atoms.
Examples of the 18 sulfamoyl groups include sulfamoyl, dimethylsulfamoyl, ethylsulfamoyl, octylsulfamoyl, dioctylsulfamoyl, undecylsulfamoyl and the like.

L¹, L^TwoMay be the same or different
Represents a divalent linking group. Here, the divalent linking group is
Consists of carbon, nitrogen, oxygen or sulfur atoms
And X¹, X^TwoIs 4 in cooperation with the carbon atom
Constructs an 8-membered ring. L¹, L ^TwoAs a specific example of
(R⁶) (R⁷)-, -C (R⁸) =, -N (R⁹)
-, -N =, -O-, -S-
You. Where R⁶, R⁷, R ⁸, R⁹Is a hydrogen atom or
Represents a substituent, the details of which are represented by R¹, R^Two, R^ThreeExplained in
Is synonymous with The 4- to 8-membered ring is saturated
Alternatively, an unsaturated condensed ring may be formed.
Examples of a cycloalkyl ring, an aryl ring or
Terror rings can be mentioned, and details thereof are as follows.¹, R^Two,
R^ThreeThis is synonymous with the one described in.

Further, as the 4- to 8-membered ring, examples of a 4-membered ring include cyclobutanedione, cyclobutenedione,
Benzocyclobutene quinone and the like as an example of a five-membered ring,
Cyclopentanedione, cyclopentenedione, cyclopentanedione, cyclopentenetrione, indandione, indantrione, tetrahydrofurandion, tetrahydrofurantrione, tetrahydropyrroledione, tetrahydropyrroletrione, tetrahydrothiophenedione, tetrahydrothiophenetrione, and the like as examples of six-membered rings , Benzoquinone, quinomethane, quinodimethane, quinone imine, quinone diimine, thiobenzoquinone, dithiobenzoquinone, naphthoquinone,
Anthraquinone, dihydrochromementione, dihydropyridinedione, dihydropyrazinedione, dihydropyrimidinedione, dihydropyridazinedione, dihydrophthalazinedione, dihydroisoquinolinedione, tetrahydroquinolinetrione, and the like, as examples of a seven-membered ring,
Examples of 8-membered rings include cycloheptanedione, cycloheptanetrione, azacycloheptanetrione, diazacycloheptanetrione, oxocycloheptanetrione, dioxocycloheptanetrione, and oxoazacycloheptanetrione. Octanetrione, azacyclooctanetrione, diazacyclooctanetrione, oxocyclooctanetrione, dioxocyclooctanetrione, oxoazacyclooctanetrione, cyclooctenedione, cyclooctadienedion, dibenzocyclooctenedione, and the like can be given. . L ¹ and L ² are X ¹ and X ²
As a ring formed jointly with the carbon atom substituted by
Preferably it is a 6-membered ring.

Among the compounds represented by the general formula (1a), the compounds represented by the following general formula (1b) are particularly preferred.

[0014]

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In the formula, R ¹⁰ , R ¹¹ , R ¹² and R ¹³ may be the same or different and each represents a hydrogen atom or a substituent. When R ¹⁰ and R ¹¹ or R ¹² and R ¹³ simultaneously serve as a substituent, they may be connected to each other to form an unsaturated condensed ring. X ¹¹ and X ²² may be the same or different;
¹ and X ² have the same meaning, and the preferred range is also the same.

In the general formula (1b), R ¹⁰ , R ¹¹ , R ¹² , R
Preferred combinations of ¹³ and X ¹¹ and X ²² will be described below. R ¹⁰ , R ¹¹ , R ¹² and R ¹³ represent a hydrogen atom, an alkyl group, a halogen atom, a cyano group, a nitro group,
Alkoxy group, alkylthio group, amino group, alkylamino group, carbonamide group, sulfonamide group, sulfamoylamino group, oxycarbonylamino group, oxysulfonylamino group, ureido group, thioureido group, acyl group, oxycarbonyl group, Preferred are a carbamoyl group, a sulfonyl group, and a sulfamoyl group, and a combination in which X ¹¹ and X ²² are an oxygen atom or a ＣC (R ¹⁴ ) (R ¹⁵ ) group. Here, R ¹⁴ and R ¹⁵ may be the same or different and each represents a halogen atom, a cyano group, an acyl group, an oxycarbonyl group, or a sulfonyl group.

In this combination, X ¹¹ and X ²² are more preferably an oxygen atom or a （C (R ¹⁴ ) (R ¹⁵ ) group at the same time, and when X ¹¹ and X ²² are simultaneously an oxygen atom, R ¹⁰ , R ¹¹ , R ¹² , and R ¹³ are more preferably electron-withdrawing groups, wherein the electron-withdrawing group means a substituent having a positive Hammett σp value. Has a halogen atom, a cyano group, a nitro group,
Examples include an acyl group, an oxycarbonyl group, a carbamoyl group, and a sulfonyl group. Particularly preferred combinations in which X ¹¹ and X ²² are simultaneously an oxygen atom include R ¹⁰ ,
R ¹¹ , R ¹² and R ¹³ are a hydrogen atom, a halogen atom, a cyano group, an alkylthio group, a carbonamide group, a sulfonamide group, an oxycarbonyl group, or a carbamoyl group, at least two of which are a halogen atom or a cyano group. Yes, the most preferred combination is R ¹⁰ ,
R ¹¹ , R ¹² and R ^{13 each} represent a hydrogen atom, a halogen atom, a cyano group, an alkylthio group having 8 to 18 carbon atoms,
A carbonamide group having 8 to 18 carbon atoms; an oxycarbonyl group having 8 to 18 carbon atoms;
18 carbamoyl groups, at least two of which are halogen atoms or cyano groups.

Among the compounds represented by the general formula (1b),
Further, a compound represented by the general formula (1c) is preferable.

[0019]

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In the formula, R ¹⁶ , R ¹⁷ , R ¹⁸ and R ¹⁹ are preferably a hydrogen atom, an alkyl group, a halogen atom, a cyano group, an alkoxy group, an acyl group or an oxycarbonyl group, more preferably a hydrogen atom, An alkyl group having 8 to 18 carbon atoms,
A halogen atom, an alkoxy group having 8 to 18 carbon atoms and an oxycarbonyl group having 8 to 18 carbon atoms, particularly preferably a hydrogen atom, an octyl group, a fluorine atom, a chlorine atom, a bromine atom and an octyloxycarbonyl group; Preferred are a hydrogen atom, an octyl group and a fluorine atom. Examples of specific compounds represented by the general formula (1a) of the present invention include the following compounds, but are not limited thereto.

[0021]

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[0022]

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[0023]

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[0024]

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[0025]

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[0026]

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The compound represented by the general formula (1a) is described, for example, in J. Chem. Soc. Perkin Trans. 1, 611 (1992), Synthesis,
It can be synthesized according to a general synthesis method such as 546 (1971). The reduction potential of these organic oxidants is noble than -1.0 volt, preferably noble than -0.5 volt, and particularly preferably -0.1 volt.
Desirably noble than 2 volts, most preferably no more than 0 volts. The value of the reduction potential Ered used here means the potential at which the organic oxidant is reduced by electron injection at the cathode in voltammetry, and the value of Ered can be accurately measured by the voltammetry. That is, tetra-n is used as a supporting electrolyte.
A voltammogram of an organic oxidizing agent of 1 × 10 ⁻³ M is measured in acetonitrile containing 0.1 M of ethylammonium perchlorate, and a half-wave potential obtained from the measured voltammogram is obtained.
The measurement is performed at 25 ° C. using platinum as the working electrode and a saturated carmel electrode (SCE) as the reference electrode.

Next, the cyanine dye represented by the general formula (2a) will be described.

[0029]

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In the formula, Z ¹ and Z ² may be the same or different and each represents a nonmetallic atom group necessary for forming a 5- or 6-membered nitrogen-containing heterocyclic ring which may be condensed; ⁴ and R ⁵ may be the same or different and each is an alkyl group,
Represents an alkenyl group or an aralkyl group, and L is 5, 7,
Or a linking group formed by linking 9 methine groups by a conjugated double bond, a, b and c each represent 0 or 1, and X represents an anion.

Further, the general formula (2a) will be described in detail. 5 or 6 which may be condensed and represented by Z ¹ and Z ²
Membered nitrogen-containing heterocyclic ring is an oxazole ring, an isoxazole ring, a benzoxazole ring, a naphthoxazole ring,
Examples thereof include a thiazole ring, a benzothiazole ring, a naphthothiazole ring, an indolenine ring, a benzoindolenine ring, an imidazole ring, a benzimidazole ring, a naphthoimidazole ring, a quinoline ring, a pyridine ring, a pyrrolopyridine ring, and a flopyrrole ring. Preferred is a 5-membered nitrogen-containing heterocyclic ring in which a benzene ring or a naphthalene ring is condensed, and most preferred is an indolenine ring. These rings may be substituted. Examples of the substituent include a lower alkyl group (for example, methyl and ethyl), an alkoxy group (for example, methoxy and ethoxy), a phenoxy group (for example, unsubstituted phenoxy and p-chlorophenoxy),
Examples thereof include a carboxyl group, a halogen atom (Cl, Br, F), an alkoxycarbonyl group (for example, ethoxycarbonyl), a cyano group, a nitro group, and a hydroxy group.

In (2a), R ⁴ and R ⁵ are an alkyl group, an alkenyl group or an aralkyl group, respectively. Alkyl groups are preferred. The carbon number of the alkyl group is 1
To 20 and more preferably 4 to 20. Examples of the alkyl group include methyl, ethyl, butyl, octyl, dodecyl, octadecyl. The alkyl group is a halogen atom (Cl, Br,
F), alkoxycarbonyl having 10 or less carbon atoms (eg, methoxycarbonyl), alkoxy having 10 or less carbon atoms (eg, methoxy, ethoxy), phenoxy having 20 or less carbon atoms (eg, 4-t-butylphenoxy), hydroxy and the like May be substituted. Aralkyl groups are 7-12
An aralkyl group having the carbon number of (e.g., benzyl, phenylethyl) is preferable, and a substituent (e.g., methyl,
Alkoxy, chloro atom). 2-1
An alkenyl group having 0 carbon atoms is preferable, and examples thereof include a 2-pentenyl group, a vinyl group, an allyl group, a 2-butenyl group, and a 1-propenyl group. It may be substituted with the substituent described for the alkyl group. Equation (2
In a), L is a linking group in which 5, 7, or 9 methine groups are conjugated with a double bond. The number of methine groups is preferably seven. The following formulas L5 and L7
And L9.

[0033]

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In the formula, R ²⁰ is a hydrogen atom, an alkyl group, a halogen atom, an aryl group, a heterocyclic group, NR ²⁵ R ²⁶ , SR
²⁷ or an OR ^27, R ²⁵ and R ²⁶ each represent a hydrogen atom, an alkyl group, an aryl group, a sulfonyl group or an acyl group, R ²⁷ represents an alkyl group or an aryl group, together with R ²⁵ and R ²⁶ They may be linked to form a 5- or 6-membered ring. R ²¹ and R ²² represent a hydrogen atom or a non-metallic atomic group which forms a 5- or 6-membered ring by bonding to each other. The alkyl group is an alkyl group having 1 to 10, more preferably 1 to 6, carbon atoms (for example, methyl, ethyl,
Propyl, butyl, isobutyl, pentyl, hexyl)
It is. Further, it may be substituted with a hydroxy group, a carboxyl group, a halogen atom (Cl, Br) or the like. Examples of the halogen atom include F, Cl, and Br.

The above aryl group has 6 to 12 carbon atoms.
Are preferred, and include a phenyl group or naphthyl
You. The aryl group may be substituted, and
Is Z ¹And the like. the above
The sulfonyl group is a sulfonyl having 1 to 10 carbon atoms.
Groups, for example, mesyl, tosyl, benzene
And a sulfonyl group and an ethanesulfonyl group.
You. The heterocyclic group includes pyridyl, furyl, pyra
Nil, pyrazolyl, pyrimidyl, thienyl, piperidi
And barbituric acid.

The acyl group has 2 to 10 carbon atoms.
Preferred are acyl groups such as acetyl and propio.
And a benzyl group and a benzoyl group. R^{twenty five}And R
²⁶May be linked to each other to form a heterocyclic ring. Hete
B ring includes piperidine, morpholine, piperazine, etc.
And substituents (eg, methyl, phenyl)
Ethoxycarbonyl). R²⁰
Is SR ²⁷It is preferred that (R²⁷Is the same as above
A) R^{twenty one}And R^{twenty two}Are connected to each other to form a 5- or 6-membered ring (eg,
For example, cyclopentene, cyclohexene)
Often, substituents (eg, methyl, t-butyl, phenyl)
). R^{twenty three}And R^{twenty four}Is water
Represents an element atom or an alkyl group. Alkyl group is as defined above
It is.

In the formula (2a), a, b and c are each 0 or 1. a and b are preferably 0. c is generally 1. However, when an anionic substituent such as carboxyl forms an inner salt with N ⁺ , c becomes 0. In the formula (2a), X is an anion. Examples of anions include halide ions (C
l, Br, I), p-toluenesulfonic acid ion, ethyl sulfate ion, PF ₆ ⁻ , BF ₄ ⁻ , ClO ₄ ^{− and the} like. A more preferred heptamethine cyanine dye is represented by the following formula (2b).

[0038]

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Where Z^ThreeAnd Z^FourBenzene ring
May be condensed with another benzene ring. R²⁸And R²⁹Is each
Represents an alkyl group, an aralkyl group or an alkenyl group.
Then R ^{twenty one}And R^{twenty two}Are each a hydrogen atom or
R represents a group of atoms necessary to form a 5- or 6-membered ring;²⁰
Represents a hydrogen atom, an alkyl group, a halogen atom, an aryl group,
Heterocyclic group, NR^{twenty five}R²⁶, SR²⁷Or OR²⁷Represents
R^{twenty five}, R²⁶, And R²⁷Is an alkyl group or aryl
R represents a group^{twenty five}And R²⁶Are linked together to form a ring
Good. R³⁰, R³¹, R³²And R³³Represents an alkyl group,
R³⁰And R³¹Or R³²And R³³Are linked to form a ring
Good. X represents an anion, and c is 0 or 1.
You.

Z^ThreeAnd Z^FourBenzene ring and its condensation
The other benzene ring may have a substituent.
Examples of substituents include Z¹And Z^TwoAnd the same as the above.
R²⁸And R²⁹Is R in the formula (2a)^FourAnd R^FiveSame as
Have righteousness. R³⁰, R³¹, R³²And R³³Alkyl group
Is R in the formula (2a)^FourAnd R^FiveAnd the alkyl group in
The same is true. R³⁰And R³¹, R³²And R³³And combine with each other
Examples of the ring formed by the above include a cyclohexane ring
I can do it. R²⁰, R^{twenty one}And R^{twenty two}Is given by the equation (L7)
R²⁰, R^{twenty one}And R^{twenty two}Has the same definition as X and c
Has the same definition as X and c in formula (2a). most
Preferably, R²⁸And R²⁹Is an alkyl group having 4 or more carbon atoms
And R^{twenty one}And R ^{twenty two}Form a 5- or 6-membered ring with²⁰But
SR²⁷(As defined above) and R³⁰, R³¹, R³²And R
³³Is a methyl group. Hereinafter, preferably used in the present invention
The following shows examples of cyanine dyes.

[0041]

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[0042]

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[0043]

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[0044]

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[0045]

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The dye of the present invention is disclosed in US Pat. No. 3,671,648.
Can be synthesized with reference to the number.

The oxidizing agent and the dye can be added to a photosensitive layer, a dye layer near the support on the same side as the photosensitive layer, and a dye layer on the side opposite to the photosensitive layer. Oxidizing agent and dye differ depending on the desired purpose 0.1 to 1000 mg / m ^2, but it is preferable 1 to 200 mg / m ² is added. The oxidizing agent and the dye are preferably dissolved in an organic solvent and added.

It is preferable that the dye is a photothermographic material substantially remaining on the image sheet where the dye is observed, because of its easiness on the earth. More preferably, it is a mono-sheet type (a type in which all materials provided for forming an image are completed as an image sheet to be observed) and a photothermographic material. Further, in order to achieve the object, a photothermographic material for infrared laser exposure is preferably used. Further, the wavelength of infrared laser exposure is preferably 750 nm or more, more preferably 800 nm or more.

The photothermographic material of the present invention forms a photographic image using a photothermographic processing method. Such a photothermographic material is disclosed in, for example, US Pat.
No. 152904, 3457075, and D.C. Morgan and B.A. "Thermally Processed SilverSy" by Shely
stems) "(Imaging Processors and
Materials (Imaging Processes and Materials) Neb
lette 8th edition, Sturge, V. Walworth, A .; Edited by Shepp, page 2,
1969).

The photothermographic material of the present invention may be any as long as it can form a photographic image by using a heat development process. The photothermographic material has a reducible silver source (eg, organic silver salt) and a catalytically active photocatalyst (eg, halogen). It is preferable that the photothermographic material contains a color tone controlling agent for controlling the color tone of silver and a reducing agent, usually in a state dispersed in an (organic) binder matrix. The photothermographic material of the present invention is stable at room temperature,
After exposure, development is performed by heating to a high temperature (for example, 80 ° C. or higher). Heating produces silver through a redox reaction between a reducible silver source (which functions as an oxidizing agent) and the reducing agent. This oxidation-reduction reaction is promoted by the catalytic action of the latent image generated by the exposure. The silver formed by the reaction of the organic silver salt in the exposed areas provides a black image, which contrasts with the unexposed areas, resulting in the formation of 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. 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 or the opposite side as the photosensitive layer, or a dye represented by the general formula (2a) may be formed on 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 the gradation. Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other forming layers.

Examples of the support applicable to the photothermographic material of the present invention include materials such as paper, polyethylene-coated paper, polypropylene-coated paper, parchment, and cloth;
Sheets or films of metals such as aluminum, copper, magnesium, zinc; glass or chromium alloy, steel,
Glass coated with a metal such as silver, gold, platinum; poly (alkyl methacrylates) (eg, poly (methyl methacrylate)), poly (esters) (eg, poly (ethylene terephthalate)), poly (vinyl acetal) ), Poly (amides) (eg, nylon), and cellulose esters (eg, cellulose nitrate, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate). The photothermographic material of the invention may contain, for example, a surfactant, an antioxidant, a stabilizer, a plasticizer, an ultraviolet absorber, and a coating aid.

The respective binder layers (for example, synthetic polymers) together with the chemicals in the photothermographic material of the present invention may form a self-supporting film. The support is made of known auxiliary materials, for example, vinylidene chloride, acrylic acid monomers (for example, acrylonitrile and methyl acrylate)
And copolymers and terpolymers of unsaturated dicarboxylic acids (eg, itaconic acid, acrylic acid), carboxymethylcellulose, poly (acrylamide); and similar polymeric materials.

Suitable binders are transparent or translucent, 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 (vinylpyrrolidone), 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)
(Eg, poly (vinyl formal) and poly (vinyl butyral)), poly (esters), poly (urethanes), phenoxy resins, poly (vinylidene chloride), poly (epoxides), poly (carbonates), There are poly (vinyl acetate), cellulose esters, and poly (amide) s. The binder may be coated from water or an organic solvent or emulsion.

The addition of toning agents is highly desirable. Examples of suitable toning agents are disclosed in Research Report No. 17029,
There are the following: imides (eg, phthalimide);
Cyclic imides, pyrazolin-5-ones, and quinazolinones (eg, 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 (eg, N- (dimethylaminomethyl) phthalimide);
Blocked pyrazoles, isothiuronium (isot
hiuronium) derivatives and certain photobleaching combinations (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 (e.g., 3-ethyl-5-((3-ethyl-2-benzothia) Zolinylidene (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-methyl) Phthalazinone + sodium p-trisulfonate); a combination of phthalazine + phthalic acid; phthalazine (including adducts of phthalazine) and maleic anhydride, and phthalic acid, 2,3-naphthalenedicarboxylic acid or o-phenylene derivative And its anhydrides (e.g., phthalic acid, Quinazolinediones, benzoxazines, naltoxazine derivatives; benzoxazine-2,4-diones (e.g., 1-hydroxybenzoic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride); , 3-
Benzoxazine-2,4-dione); pyrimidines and asymmetric triazines (e.g., 2,4-dihydroxypyrimidine), and tetraazapentalene derivatives (e.g., 3,6-dimerocapto-1,4-diphenyl-) 1
H, 4H-2,3a, 5,6a-tetraazapentalene. A preferred toning agent is phthalazine:

[0056]

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Is as follows. The reducing agent may contain a so-called photographic developer, for example, phenidone, hydroquinones, catechol and the like, but hindered phenol is preferred. A color light-sensitive material as disclosed in U.S. Pat. No. 4,460,681 is also conceivable for realizing the present invention.

Examples of suitable reducing agents are described in US Pat.
Nos. 448, 3773512, 3959633, and Research Disclosure Nos. 17029 and 29.
963, and include: aminohydroxycycloalkenone compounds (eg, 2-hydroxy-piperidino-2-cyclohexenone); aminoreductones esters (eg, Piperidinohexose reductone monoacetate); N-hydroxyurea derivatives (for example, Np-
Methylphenyl-N-hydroxyurea); hydrazones of aldehydes or ketones (eg, anthracenaldehyde phenylhydrazone); phosphoramidophenols; phosphoramidoanilines; polyhydroxybenzenes (eg, hydroquinone, t-butyl-hydroquinone) , Isopropylhydroquinone and (2,5-dihydroxy-phenyl) methylsulfone); sulfhydroxamic acids (e.g., benzenesulfhydroxamic acid); sulfonamidoanilines (e.g., 4- (N-
Methanesulfonamido) aniline); 2-tetrazolylthiohydroquinones (for example, 2-methyl-5- (1-
Phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (e.g., 1,2,3,4-
Amidooxins; Azines (for example, a combination of an aliphatic carboxylic acid arylhydrazide and ascorbic acid); a combination of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine; Hydroxanoic acids; Azines and sulfone Combinations of amidophenols; α-cyanophenylacetic acid derivatives; bis-β-naphthol and 1,3-
5-pyrazolones; sulfonamidophenol reducing agents; 2-phenylindane-1,3-dione and the like; chromans; 1,4-dihydropyridines (e.g., 2,6-dimethoxy-3) , 5-dicarbethoxy-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), ultraviolet-sensitive ascorbic acid derivatives and 3-pyrazolidones. Preferred developers are hindered phenols of the general formula (A):

[0059]

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Wherein R is a hydrogen atom or 1 carbon atom
To 10 alkyl groups (for example, -C _FourH₉, 2,4,4
-Trimethylpentyl);^FiveAnd R⁶Is a carbon source
An alkyl group having 1 to 5 children (for example, methyl, ethyl, t
-Butyl).

Silver halide useful as a catalytically active amount of photocatalyst can be any photosensitive silver halide (eg, silver bromide, silver iodide, silver silver, silver chlorobromide, silver iodobromide, chloroiodoodor). Silver iodide), but preferably contains iodine ions. The silver halide may be added to the image forming layer by any method, in which case the silver halide is arranged close to the reducible silver source. In general, it is preferred that the silver halide contains from 0.75 to 30% by weight, based on the reducible silver source. Silver halide may be prepared by conversion of the silver soap portion by reaction with a halide ion, may be preformed and added during the generation of the soap, or a combination of these methods is possible. The latter is preferred.

The reducible silver source can be any material containing a reducible silver ion source. Silver salts of organic and heteroorganic acids, especially long chains (10-30, preferably 15-25
) Aliphatic carboxylic acids 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 are described in Research Disclosure No. 1702.
9 and 29996, and include the following:
Salts of organic acids (eg, gallic acid, oxalic acid, behenic acid,
Stearic acid, palmitic acid, lauric acid, etc.); carboxyalkylthiourea salt of silver (for example, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea); aldehyde Silver complexes (e.g., aldehydes (formaldehyde, acetaldehyde, butyraldehyde), hydroxy-substituted acids (e.g., salicylic acid, benzoic acid, 3,5-
Dihydroxybenzoic acid, 5,5-thiodisalicylic acid),
Silver salts or complexes of thioenes (eg, 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 silver and nitrogen acids selected from triazoles and benzotriazoles; 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 content of 3 g / m ² or less. More preferably, it is 2 g / m ² or less.

Such a light-sensitive material may contain an antifoggant. 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 unfriendly. As the non-mercury antifoggant, antifoggants such as those disclosed in U.S. Pat. Nos. 4,460,075 and 4,452,885 and Japanese Patent Publication No. 59-57234 are preferred.

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 (eg, F, Cl, Br and I) and X ³ is hydrogen or halogen. Examples of suitable antifoggants include:

[0065]

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Even more suitable antifoggants are disclosed in US Pat. No. 5,028,523 and our UK patent application No. 92221.
Nos. 383.4, 9300147.7, 931179
No. 0.1.

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.
Nos. 3-304242, 63-15245, U.S. Pat. Nos. 4,639,414, 4,740,455, and 4,419.
Sensitizing dyes described in JP-A Nos. 66, 4751175 and 48335096 can be used.

[0068]

EXAMPLE 1 Photosensitive emulsion mixed solution NaOH 89 g of distilled water in preparing solution stearate 131g behenic acid 635g of distilled water 13 liters 85 ° C. 15 minutes A 1500 ml solution of concentrated HNO ₃ 19 ml of distilled water 50ml solution AgNO ₃ 365 g of distilled water 2500 ml solution 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

While maintaining the temperature of the solution at 85 ° C., the solution was added over 5 minutes with vigorous stirring.
Add over 5 minutes. After stirring for 20 minutes as it is, 35
Cool down to ° C. Add the solution over 5 minutes with more vigorous stirring at 35 ° C. and continue stirring for 90 minutes.
Thereafter, the solution was added, the stirring was stopped, and the mixture was left to stand. The aqueous phase was removed together with the contained salt to obtain an oil phase. The solvent was removed to remove traces of water. Then, the solution was added and the mixture was stirred vigorously at 50 ° C. Thereafter, the solution was added over 20 minutes and stirred for 105 minutes to obtain Emulsion A.

The following layers were sequentially formed on a polyethylene terephthalate support colored blue with Dye-A. Drying was performed at 75 ° C. for 5 minutes each.

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Back side coating Antihalation layer (wet thickness 80 microns) Polyvinyl butyral (10% isopropanol solution) 150 ml Dye (solvent uses DMF) Table 1 Organic oxidant (solvent uses acetone) Table 1 Described in

[0073]

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Photosensitive layer side coating Photosensitive layer (wet thickness 140 μm) 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 Antifoggant-3 (0.85% methanol solution) 10 ml Phthalazone (4.5% DMF solution) 8 ml Reducing agent-1 (10% acetone solution) 13 ml

[0075]

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Surface protective layer (wet thickness 100 microns) 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 0.5g

(Measurement of Fluorescence Spectrum) Fluorescence Spectrometer “Model NIR-” manufactured by Ritsu Applied Chemical Co., Ltd.
0818-I ”, the fluorescence emission intensity of the obtained sample was measured. The excitation light source used was a 300 W Xe lamp, 800 nm manufactured by Hoya Color Filter Glass Co., Ltd.
After monochromatization by the interference filter "R-76" and the heat prevention filter "R-70", the sample is irradiated with light through a flexible liquid fiber (containing distilled water) manufactured by Ultrafine Technology having a light transmittance of 0.1 to emit light. The fluorescence intensity to be measured was measured with a Ge detector cooled to the temperature of liquid nitrogen. The fluorescence intensity of each sample at 875 nm is shown in Table 1 as a relative value when the value of sample 2 is set to 100.

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

Evaluation of Residual Color Samples subjected to heat development without exposure were visually evaluated. ：: good △: worried about residual color ×: problematic with residual color

[0080]

[Table 1]

As can be seen from Table 1, the sample of the present invention has no problem in residual color and has good sharpness. The improvement in sharpness may be due to less fluorescence.

Example 2 Preparation of Photosensitive Emulsion B Solution 131 g of stearic acid 635 g of behenic acid Distilled water 13 liters Mixed at 85 ° C. for 15 minutes Solution A CuBr AgI prepared in advance (I = 4 mol%) 0.06 μm (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 4300ml solution polyvinylbutyral 290g isopropanol 3580ml

While maintaining the temperature of the solution at 85 ° C., the solution A is added with vigorous stirring over 10 minutes, the solution is added over 5 minutes, and then the solution is added 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. Thereafter, the solution was added, the stirring was stopped and the mixture was left to stand, and the aqueous phase was extracted together with the salt contained therein to obtain an oil phase. After removing the traces of water by removing the solvent, the solution was added and the mixture was stirred vigorously at 50 ° C. Later, 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. The results are shown in Table 2. The sample using the dye of the present invention had no problem with residual color as in Example 1, and had high sharpness.

[0085]

[Table 2]

Claims (2)

[Claims] 1. A photothermographic material comprising an organic oxidizing agent represented by the following general formula (1a) and a dye represented by the following general formula (2a). Embedded image In the formula, X ¹ and X ² may be the same or different and each represents an oxygen atom, a sulfur atom, a ＮＲNR ¹ group or ＣＲCR ² R ³
M and n represent an integer of 0 to 3 such that m + n ≧ 2. R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a substituent. L ¹ and L
² may be the same or different and each represents a divalent linking group. Embedded image Wherein, Z ¹ and Z ² may be the same or different, represents a non-metallic atomic group necessary for forming a nitrogen-containing heterocyclic ring each may be condensed 5 or 6 membered, R ⁴ and R ⁵ may be the same or different and each represents an alkyl group, an alkenyl group or an aralkyl group; L represents a linking group formed by linking 5, 7, or 9 methine groups by a conjugated double bond; b and c each represent 0 or 1, and X represents an anion. 2. The photothermographic material according to claim 1, wherein the reduction potential of the organic oxidant represented by the general formula (1a) is more noble than -0.5 V.