JP2001109102A - Heat developable photographic sensitive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat developable photographic sensitive material for the production of a printing plate having high sensitivity and high density, suppressed fog, excellent preservability, suppressed rise of fog with the lapse of time, ultrahigh contrast and excellent dot reproducibility. SOLUTION: The heat developable photographic sensitive material contains photosensitive silver halide, an organic silver salt, a reducing agent, a contrast enhancer and a compound of formula 1 or 2. In the formulae 1 and 2, R1 and R2 are each alkyl, alkoxy, aryloxy or the like, n1 is a positive integer of >=1 and n2 is a positive integer of >=3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a black and white photothermographic material for printing plate making.

[0002]

2. Description of the Related Art Conventionally, in the field of printing plate making, waste liquid caused by wet processing of an image forming material has become a problem in terms of workability. In recent years, the amount of treated waste liquid has been reduced from the viewpoint of environmental protection and space saving. It is strongly desired. Therefore, a technique relating to a photothermographic material capable of performing efficient exposure by a laser imagesetter and forming a high-resolution and clear black image has been expected. As this technique, for example, U.S. Patent Nos. 3,152,904 and 3,48
7,075 and D.C. “Dry Silver Photographic Materials (Dry Silver P) by Morgan
photographic Materials) ”(H
andbook of ImagingMateria
ls, Marcel Dekker, Inc. Forty-eighth
1991) is well known. Since these photosensitive materials are usually developed at a temperature of 80 ° C. or higher, they are called photothermographic materials.

[0003] Printing plate making films are required to have ultra-high contrast, high density and low fog. However, in the conventional photothermographic material as described above, it is difficult to increase the density, and when the density is increased, there is a problem that the fog is greatly deteriorated. Further, when a large amount of an organic silver salt is added in order to increase the concentration, not only the fog rises but also the fog increases with time, which causes a problem in storage stability. Further, at present, an image having low fog and a super-high contrast sufficient to be required as a printing plate making film has not been obtained.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a high-sensitivity, high-density, ultra-high-contrast, low-fogging, superior storage stability, and low fog over time. An object of the present invention is to provide a heat-developable photographic light-sensitive material for printing plate making which has excellent dot reproducibility.

[0005]

The object of the present invention has been attained by the following.

(1) In a photothermographic material containing a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent, at least one compound represented by the following general formula (1) or (2) is used. A heat-developable photographic light-sensitive material comprising a seed.

[0007]

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In the formula, R ₁ and R ₂ each represent an alkyl group, an alkoxy group, an aryloxy group, an aryl group, an isothiocyanate group, an amino group, an alkylthio group, an arylthio group, an azide group, or a derivative thereof; R ₁ and R ₂ may be the same or different. n1 represents a positive integer of 1 or more, and when n1 is 2 or more, a plurality of R ₁ and R ₂ may be the same or different.

[0009]

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In the formula, R ₁ and R ₂ are each represented by the general formula (1)
Of R _1, represents R ₂ as defined in group, R _1, R ₂ may be different even in the same. n2 represents a positive integer of 3 or more, and a plurality of R ₁ and R ₂ may be the same or different.

(2) In a photothermographic material containing a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent, a silver complex salt of the compound represented by the above formula (1) or (2) A heat-developable photographic light-sensitive material comprising at least one kind of

(3) In a photothermographic material containing a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent, at least one compound represented by the following general formula (3) or (4) is used. A heat-developable photographic light-sensitive material comprising a seed.

[0013]

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In the formula, R ₃ and R _{4 each} represent a hydrogen atom, having 1 to 3 carbon atoms.
Represents an alkyl group up to However, R ₃ and R ₄ are not simultaneously hydrogen atoms. R ₅ and R _{6 each} represent a hydrogen atom and a carbon number of 1 to
And R ₇ represents a hydroxyl group, an amino group or an alkyl group having 1 to 3 carbon atoms. R _8, R ₉ represents a hydrogen atom, an alkyl group having up to 5 carbon atoms, an acyl group or a -COOM ₂ group up to 18 carbon atoms. Where R ₈ and R ₉
Cannot be hydrogen atoms at the same time. M ₁ is a hydrogen atom,
Represents an alkali metal atom or an ammonium group. M ₂ represents a hydrogen atom, an alkyl group having up to 4 carbon atoms, an alkali metal atom, an aryl group, an aralkyl group having up to 15 carbon atoms. m represents 0, 1 or 2.

(4) In a heat-developable photographic material containing a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent, a silver complex salt of the compound represented by formula (3) or (4) A heat-developable photographic light-sensitive material comprising at least one kind of

(5) The heat-developable photographic material as described in any one of (1) to (4) above, wherein the photosensitive layer or a layer adjacent thereto contains a hydrazine derivative.

(6) The above-mentioned (1), which comprises at least one kind of an amine compound or a quaternary onium compound.
6. The photothermographic material according to any one of items 1 to 5.

(7) The photothermographic material according to any one of the above items (1) to (6), which forms a high-contrast image having a gamma of 10 or more.

Hereinafter, the present invention will be described in detail.

In the present invention, in at least one layer of the photothermographic material, the compound represented by formula (1) or (2) or the compound represented by formula (3) or (4) is used. (Hereinafter, these compounds may be referred to as the compounds of the present invention).

The compound represented by the general formula (1) or (2) is a compound called a phosphazene compound.

In the general formula (1) or (2), R
_The amino groups represented by ₁ and R ₂ include those having a substituent. Examples of the substituent include an aliphatic group such as an alkyl group and an aromatic group such as a phenyl group. Examples of the amino group having a substituent include, for example, a group in which one or two aliphatic groups are substituted, a group in which one or two aromatic groups are substituted, a group in which an aliphatic group and an aromatic group are substituted, and a cyclic group. And an amino group.

The compound represented by the general formula (1) or (2) of the present invention is a phosphazene derivative whose basic skeleton is composed of a P = N bond, and a part of the substituent is an ionic side chain group. Alternatively, the case of a pi-electron-based compound side chain group or a polyether side chain group is also included.

These compound groups include a high molecular weight compound group in which the P = N bond is linear, and a cyclic compound group and a cyclic compound group. The method of synthesizing these compounds is described in more detail as follows: (PNF ₂ ) ₃ , (PNF ₂ ) ₄ , (PNF ₂ ) n
And the like, in which the side group such as is a trimer, tetramer, or n-mer of an F atom, (PNCl ₂ ) ₃ , (PNCl ₂ ) ₄ , (PNCl ₂ )
Compounds in which the side group such as n (n <15) is a Cl atom trimer, tetramer, n-mer, (PNBr ₂ ) ₃ , (PNB
(Pr ₂ ) ₄ , (PNBr ₂ ) n, etc., a compound in which the side chain group is a Br atom trimer, tetramer, n-mer, (PNI ₂ ) ₃ , (PNI)
₂ ) ₄ , (PNI ₂ ) n or the like has a side chain group which is a halogen atom of a trimer, tetramer, or n-mer compound of I atom, and is represented by C ₆ H ₅ ON.
a, CH ₃ C ₆ H ₄ ONa, (C ₆ H ₅ O) ₂ Ca, CF ₃ C ₆
Fats such as H ₄ reaction of the metal salt of an aromatic organic compound such as ONa, C ₆ H ₅ aromatic compound having a hydroxyl group such as OH or _{CH 2 = C (CH 3)} -COOCH 2 CH 2 OH Aromatic compounds capable of nucleophilic substitution with a halogen atom on the P atom, such as aromatic alcohols, aromatic amines such as C ₆ H ₅ NH ₂ , amines such as aniline, sodium hydroxide, sodium carbonate, etc. And a method of mixing with a halogen acceptor compound.

The phosphazene derivative is generally synthesized in this manner.
There is no particular limitation.

The aromatic side group is generally a group derived from a compound having an aromatic ring.

[0027]

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And a group derived from a compound having a hydroxyl group as a functional group on an aromatic ring.

Further, the following groups derived from compounds having an amino group as a functional group on an aromatic ring such as aniline and phenylenediamine are exemplified.

[0030]

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Alternatively, examples thereof include the following groups derived from compounds having a mercapto group as a functional group on an aromatic ring such as thiophenol and dimercaptobenzene.

[0032]

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The combination of the side chain groups may not necessarily be composed of a single group, but may be a combination selected from a plurality of these groups.
It can be arbitrarily selected to have a solubility of 1 g or less in 100 g of a 40 ° C. aqueous solution adjusted to H10.00.
In addition, Chem. Rev .. , 1972, vol72,
No. And functional groups contained in the compounds shown in Nos. 4,315 to 356. These functional groups may further have a hydrophilic substituent such as a carboxyl group, a sulfonic acid group or a phosphoric acid group. Is also good.

Next, specific examples of the compound represented by the general formula (1) or (2) are shown, but the present invention is not limited to these.

(Chain compound) L-1 [NP (NCS) ₂ ] _n L-2 [NP (OMe) ₂ ] _n L-3 [NP (OEt) ₂ ] _n L-4 [NP (OCH ₂ CF) ₃ ) ₂ ] _n L-5 [NP (OCH ₂ C ₂ F ₅ ) ₂ ] _n L-6 [NP (OCH ₂ CF ₂ CF ₂ H) ₂ ] _n L-7 [NP (OCH ₂ C ₃ H ₇₎ ) ₂ ] _n L-8 [NP (OCH ₂ CF ₃ ) (OCH ₂ C ₃ F ₇ )] _n L-9 [NP (OCH ₂ (CF ₂ ) ₆ CF ₃ ) ₂ ] _n L-10 [NP ( OCH ₂ C ₂ F ₅ ) (OCH ₂ C ₃ F ₇ )] _n L-11 [NP (OCH ₂ CF ₂ CF ₂ H) (OCH ₂ C ₆ F ₁₂ H)] _n L-12 [NP (OPh) ₂ ] _n L-13 [NP (OC ₆ H ₄ F-p) ₂ ] _n L-14 [NP (OC ₆ H ₄ CF ₃ -m) ₂ ] _n L-15 [NP (OC ₆ H ₄ Cl−) p) _{2] n} L-1 _{[NP (OC 6 H 3 Cl} 2 -2,4) 2] n L-17 [NP (OC 6 H 4 C 6 H 5 -p) 2] n L-18 [NP (NHMe) 2] n L- 19 [NP (NHEt) ₂ ] _n L-20 [NP (NHPr-n) ₂ ] _n L-21 [NP (NHBu-n) ₂ ] _n L-22 [NP (NHPh) ₂ ] _n L-23 [ _{NP (NMe 2) 2] n} L-24 [NP (NC 5 H 10) 2] n L-25 [NP (NEt 2) Cl] n L-26 [NP (NEt 2) (NH 2)] n L -27 [NP (NEt ₂ ) (NHMe)] _n L-28 [NP (NEt ₂ ) (NHEt)] _n L-29 [NP (NEt ₂ ) (NHPr-n)] _n L-30 [NP (NEt) ₂ ) (NHBu-n)] _n L-31 (NPPh ₂ ) _n L-32 [NP (SEt) ₂ ] _n

[0036]

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(Cyclic compound) C-1 [NP (CF ₃ ) ₂ ] ₃ C-2 (NPPh ₂ ) ₃ C-3 (NPPh ₂ ) ₄ C-4 [NP (C ₆ H ₄ Cl-p) ₂ ] ₃ C-5 (NPet ₂ ) ₃ C-6 (NPet ₂ ) ₄ C-7 [NP (OCH ₂ CF ₃ ) ₂ ] C-8 [NP (OMe) ₂ ] ₃ C-9 [NP (OMe) ₂ ] ₄ C-10 [NP (OEt) ₂ ] ₃ C-11 [NP (OEt) ₂ ] ₄ C-12 [NP (OPr-i) ₂ ] ₃ C-13 [NP (OPr-i) ₂ ] ₄ C-14 [NP (OBu-n) ₂ ] ₃ C-15 [NP (OBu-n) ₂ ] ₄ C-16 [NP (OCH ₂ Ph) ₂ ] ₃ C-17 [NP (OCH ₂ Ph) _{2] 4 C-18 [NP} (OPh) 2] 3 C-19 [NP (OPh) 2] 4 C-20 [NP (SEt) 2] 4 C-21 [NP (SP _{) 2] 3 C-22 [} NP (NHMe) 2] 3 C-23 [NP (NHMe) 2] 4 C-24 [NP (NHEt) 2] 3 C-25 [NP (NHEt) 2] 4 C- 26 [NP (NHBu-n) ₂ ] ₃ C-27 [NP (NHBu-n) ₂ ] _n C-28 [NP (NMe ₂ ) ₂ ] ₃ C-29 [NP (NMe ₂ ) ₂ ] ₄ C- 30 [NP (NEt ₂ ) ₂ ] ₃ C-31 [NP (NEt ₂ ) ₂ ] ₄ C-32 [NP (NMePh) ₂ ] ₃ C-33 N ₃ P ₃ Ph ₃ (NHMe) ₃ (cis) C -34 N ₃ P ₃ Ph ₃ (NHMe) ₃ (trans) C-35 N ₃ P ₃ Ph ₃ (NHEt) ₃ (cis) C-36 N ₃ P ₃ Ph ₃ (NHEt) ₃ (trans) C-37 N ₃ P ₃ (NHEt) ₄ (OCH ₂ CF ₃ ) ₂ (gem) C-38 N ₃ P ₃ (NHEt) ₄ (OCH ₂ CF ₃ ) ₂ (non-gem) C-39 N ₃ P ₃ (OC ₆ H ₅ ) ₄ (NH ₂ ) ₂ (gem) C-40 N ₃ P ₃ (OC ₆ H ₅ ) ₄ (NH ₂ ) ₂ (non-gem) C-41 [NP (NCS) ₂ ] ₃ C-42 [NP (N ₃ ) ₂ ] ₃ C-43 [NP (OPr-n) ₂ ] ₃ C-44 [NP ( OCH ₂ CF ₃ ) ₂ ] ₃ C-45 [NP (SEt) ₂ ] ₃ C-46 [NP (NH ₂ ) ₂ ] ₃ C-47 [NP (CF ₃ ) ₂ ] ₄ C-48 (NPPh ₂ ) ₄ C-49 [NP (OPr-n) ₂ ] ₄ C-50 [NP (NH ₂ ) ₂ ] ₄ C-51 [NP (OMe) ₂ ] ₅ C-52 [NP (NMe ₂ ) ₂ ] ₅ C −53 [NP (OMe) ₂ ] ₆ C-54 [NP (NMe ₂ ) ₂ ] ₆ C-55 [NP (OMe) ₂ ] ₈ C-56 [NP (NMe ₂ ) ₂ ] ₈

[0038]

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[0039]

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[0040]

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[0041]

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(Chain compound)

[0043]

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In the present invention, the object of the present invention can also be achieved by adding a silver complex compound of the compound represented by the general formula (1) or (2). The silver complex compound is obtained by mixing the compound with silver nitrate. Forward mixing method, reverse mixing method, simultaneous mixing method,
A controlled double jet method as described in JP-A-1227643 is preferably used.

In the present invention, the compound represented by the above general formula (1) or (2) or a silver complex salt thereof is added only when the silver halide emulsion layer is added before coating. It is good, but it is preferred that the chemical ripening of the silver halide grains in the silver halide emulsion layer is completed, and it is more preferable to add it before the start of the chemical ripening.

Next, the compound represented by formula (3) or (4) will be described.

In the above general formula (3) or (4),
Examples of the alkyl group having 1 to 4 carbon atoms include a methyl, ethyl, propyl and butyl group.

The acyl group having up to 18 carbon atoms includes, for example, an acetyl group and a benzoyl group, and the aralkyl group having up to 15 carbon atoms includes, for example, a benzyl group and a phenethyl group. The aryl group includes a phenyl group, a naphthyl group and the like.

[0049] As the alkali metal atom M _1, for example, sodium ions, potassium ions.

Various synthetic methods are known for the above-mentioned compound of the present invention. For example, a Strecker amino acid synthetic method known as an amino acid synthetic method may be used. The reaction is performed by alternately adding acetic anhydride.

Next, specific examples of the compound represented by formula (3) or (4) of the present invention are shown, but the present invention is not limited to these.

[0052]

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[0053]

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In the present invention, the object of the present invention can also be achieved by adding a silver complex salt compound of the compounds represented by the general formulas (3) and (4).
The silver complex compound is obtained by mixing the compound with silver nitrate. A forward mixing method, a reverse mixing method, a simultaneous mixing method, and a controlled double jet method as described in JP-A-9-127463 are preferably used.

In the present invention, in order to add the compound represented by formula (3) or (4) or a silver complex salt thereof, if the silver halide emulsion layer is added before coating. It is good, but it is preferred that the chemical ripening of the silver halide grains in the silver halide emulsion layer is completed, and it is more preferable to add it before the start of the chemical ripening.

The above compounds of the present invention may be used alone or in combination.

The photothermographic material of the present invention contains a photosensitive silver halide, an organic silver salt, a reducing agent and a contrasting agent in addition to the compound of the present invention. And ethylene compounds are preferably used.

The hydrazine-based high contrast agent particularly preferably used includes a compound represented by the following general formula [H].

[0059]

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In the formula, A ₀ represents an aliphatic group, an aromatic group, a heterocyclic group or a -G ₀ -D ₀ group, B ₀ represents a blocking group, and A ₁ and A ₂ are both hydrogen atoms or Represents a hydrogen atom and the other represents an acyl group, a sulfonyl group or an oxalyl group. Here, G ₀ is a -CO- group, a -COCO- group,-
CS-group, -C (= NG ₁ D ₁ ) -group, -SO- group, -S
O ₂ - group or _{-P (O) (G 1 D} 1) - represents a group, G ₁ is a bond, -O- group, -S- group, or -N (D ₁₎ - represents a group, D ₁ Represents an aliphatic group, an aromatic group, a heterocyclic group or a hydrogen atom, and when a plurality of D ₁ are present in the molecule, they may be the same or different. D ₀ is a hydrogen atom,
Represents an aliphatic group, an aromatic group, a heterocyclic group, an amino group, an alkoxyl group, an aryloxy group, an alkylthio group or an arylthio group.

In the general formula [H], the aliphatic group represented by A ₀ preferably has 1 to 30 carbon atoms.
Particularly, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms is preferable, and examples thereof include a methyl group, an ethyl group, a t-butyl group, an octyl group, a cyclohexyl group, and a benzyl group. (For example, an aryl group,
Alkoxyl group, aryloxy group, alkylthio group,
Arylthio, sulfoxy, sulfonamido, sulfamoyl, acylamino, ureido, etc.).

In the general formula [H], the aromatic group represented by A ₀ is preferably a monocyclic or condensed-ring aryl group.
For example, a benzene ring or a naphthalene ring is mentioned, and A ₀
The heterocyclic group represented by is preferably a heterocyclic ring containing at least one hetero atom selected from nitrogen, sulfur, and oxygen atom in a single ring or a condensed ring, for example, a pyrrolidine ring,
Imidazole ring, a tetrahydrofuran ring, a morpholine ring, a pyridine ring, a pyrimidine ring, a quinoline ring, a thiazole ring, a benzothiazole ring, a thiophene ring, a furan ring, and, in -G ₀ -D ₀ group represented by A _0, G ₀ represents a -CO- group, -COCO- group, -CS- group, -C (= N
G ₁ D ₁ ) —, —SO—, —SO ₂ —, or —P
(O) represents a (G ₁ D ₁ ) — group. G ₁ is just a bond,
O—, —S— or —N (D ₁ ) —, wherein D ₁ represents an aliphatic group, an aromatic group, a heterocyclic group or a hydrogen atom;
When multiple D ₁ are present in a molecule, they may be the same or different. D ₀ represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an amino group, an alkoxyl group, an aryloxy group, an alkylthio group, an arylthio group,
Preferred D ₀ includes a hydrogen atom, an alkyl group, an alkoxyl group, an amino group and the like. Aromatic groups A _0, heterocyclic group or -G ₀ -D ₀ group may have a substituent.

Particularly preferred as A ₀ are an aryl group and a -G ₀ -D ₀ group.

In the general formula [H], A ₀ preferably contains at least one diffusion-resistant group or silver halide-adsorbing group. As the diffusion-resistant group, a ballast group commonly used in immobile photographic additives such as couplers is preferable, and as the ballast group, a photographically inert alkyl group, alkenyl group, alkynyl group, alkoxyl group, phenyl group,
Examples thereof include a phenoxy group and an alkylphenoxy group, and the total number of carbon atoms in the substituent is preferably 8 or more.

In the general formula [H], examples of the silver halide adsorption promoting group include thiourea, thiourethane group, mercapto group, thioether group, thione group, heterocyclic group, thioamide heterocyclic group, mercapto heterocyclic group, 64-9
No. 0439.

In the general formula [H], B ₀ represents a blocking group, preferably a -G ₀ -D ₀ group, and G ₀ represents-
CO- group, -COCO- group, -CS- group, -C (= NG
₁ D ₁₎ - group, -SO- group, -SO ₂ - group or -P
(O) A preferred (G ₀ ) representing a (G ₁ D ₁ ) — group is
C _O - group, -COCO- group, and the like, G ₁ is a single bond, -O- group, -S- group, or -N (D ₁₎ - represents a group, D ₁ is an aliphatic group, an aromatic Represents a group, a heterocyclic group or a hydrogen atom, and when a plurality of D ₁ are present in a molecule, they may be the same or different. D ₀ represents a hydrogen atom, an aliphatic group, an aromatic group, a heterocyclic group, an amino group, an alkoxyl group, an aryloxy group, an alkylthio group, or an arylthio group, and preferred D ₀ is a hydrogen atom, an alkyl group, an alkoxyl group, And an amino group. A ₁ ,
A ₂ is a hydrogen atom, or one is a hydrogen atom, and the other is an acyl group (acetyl group, trifluoroacetyl group, benzoyl group, etc.), a sulfonyl group (methanesulfonyl group, toluenesulfonyl group, etc.), or an oxalyl group (ethoxalyl group) Etc.).

Next, specific examples of the compound represented by the general formula [H] are shown below, but it should not be construed that the invention is limited thereto.

[0068]

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[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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Other hydrazine derivatives which can be preferably used include compounds H-1 to H-29 described in columns 11 to 20 of US Pat. No. 5,545,505.
U.S. Pat. No. 5,464,738, column 9 to column 1
Compounds 1 to 12 described in 1. These hydrazine derivatives can be synthesized by a known method.

The hydrazine derivative-added layer is a photosensitive layer containing silver halide and / or a layer adjacent to the photosensitive layer. The optimum amount is not uniform depending on the particle size of the silver halide grains, the halogen composition, the degree of chemical sensitization, the type of the inhibitor, etc., but is preferably from 10 ^-6 mol per mol of silver halide.
The range is preferably about 10 ^-1 mol, particularly preferably 10 ^-5 mol to 10 ^-2 mol.

Next, as the ethylene hardening agent preferably used, a compound represented by the following general formula [G] can be mentioned.

[0077]

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In the general formula [G], X and R are represented in the form of cis. However, the general formula [G] includes X and R in the form of trans. This is the same in the structural representation of a specific compound.

In the formula, X represents an electron-withdrawing group, and W is a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, a halogen atom, an acyl group, a thioacyl group, an oxalyl group, an oxyoxalyl group. , Thiooxalyl group, oxamoyl group, oxycarbonyl group, thiocarbonyl group, carbamoyl group, thiocarbamoyl group,
Sulfonyl group, sulfinyl group, oxysulfinyl group, thiosulfinyl group, sulfamoyl group, oxysulfinyl group, thiosulfinyl group, sulfinamoyl group, phosphoryl group, nitro group, imino group, N-carbonylimino group, N-sulfonylimino group, dicyano It represents an ethylene group, an ammonium group, a sulfonium group, a phosphonium group, a pyrylium group, or an immonium group.

R represents a halogen atom, a hydroxy group, an alkoxyl group, an aryloxy group, a heterocyclic oxy group, an alkenyloxy group, an acyloxy group, an alkoxycarbonyloxy group, an aminocarbonyloxy group, a mercapto group, an alkylthio group, an arylthio group, Organic or inorganic salts of ring thio group, alkenylthio group, acylthio group, alkoxycarbonylthio group, aminocarbonylthio group, hydroxy group or mercapto group (for example, sodium salt, potassium salt, silver salt, etc.), amino group, alkyl Amino group, cyclic amino group (for example, pyrrolidino group),
It represents an acylamino group, an oxycarbonylamino group, a heterocyclic group (e.g., a 5- to 6-membered nitrogen-containing heterocyclic ring such as a benzotriazolyl group, an imidazolyl group, a triazolyl group, or a tetrazolyl group), a ureido group, or a sulfonamide group. X and W, and X and R may be bonded to each other to form a cyclic structure. The ring formed by X and W includes, for example, pyrazolone, pyrazolidinone, cyclopentanedione, β-
Ketoractone, β-ketolactam and the like.

The general formula [G] will be further described.
Is a substituent whose Hammett's substituent constant σp can take a positive value. Specifically, a substituted alkyl group (eg, halogen-substituted alkyl), a substituted alkenyl group (eg, cyanovinyl), a substituted / unsubstituted alkynyl group (eg, trifluoromethylacetylenyl, cyanoacetylenyl), and a substituted aryl group (eg, cyanovinyl) Phenyl, etc.), substituted / unsubstituted heterocyclic groups (pyridyl, triazinyl, benzoxazolyl, etc.), halogen atoms, cyano groups, acyl groups (acetyl, trifluoroacetyl, formyl, etc.),
Thioacetyl group (thioacetyl, thioformyl, etc.), oxalyl group (methyloxalyl, etc.), oxyoxalyl group (ethoxalyl, etc.), thiooxalyl group (ethylthiooxalyl, etc.), oxamoyl group (methyloxamoyl, etc.), oxycarbonyl group (ethoxycarbonyl, etc.) etc),
Carboxyl group, thiocarbonyl group (such as ethylthiocarbonyl), carbamoyl group, thiocarbamoyl group, sulfonyl group, sulfinyl group, oxysulfonyl group (such as ethoxysulfonyl), thiosulfonyl group (such as ethylthiosulfonyl), sulfamoyl group, and oxysulfinyl Group (such as methoxysulfinyl), thiosulfinyl group (such as methylthiosulfinyl), sulfinamoyl group,
Sphinamoyl group, phosphoryl group, nitro group, imino group, N-carbonylimino group (N-acetylimino, etc.), N-sulfonylimino group (N-methanesulfonylimino, etc.), dicyanoethylene group, ammonium group, sulfonium group, phosphonium Groups, a pyrylium group, and an immonium group, and a heterocyclic group in which an ammonium group, a sulfonium group, a phosphonium group, an immonium group, and the like form a ring is also included. Particularly preferred as the σp value is a substituent having a value of 0.30 or more.

Examples of the alkyl group represented by W include methyl, ethyl, trifluoromethyl and the like, examples of the alkenyl group include vinyl, halogen-substituted vinyl and cyanovinyl, and examples of the alkynyl group include acetylenyl and cyanoacetylenyl. Examples of the group include nitrophenyl, cyanophenyl, and pentafluorophenyl, and examples of the heterocyclic group include pyridyl, pyrimidyl, triazinyl, succinimide, tetrazolyl, triazolyl, imidazolyl, and benzoxazolyl. W is σ
A p-value is preferably a positive electron-withdrawing group, and more preferably, the value is 0.30 or more.

Among the above substituents for R, preferred are a hydroxy group, a mercapto group, an alkoxyl group, an alkylthio group, a halogen atom, an organic or inorganic salt of a hydroxy group or a mercapto group, and a heterocyclic group. Examples include an organic or inorganic salt of a hydroxy group, an alkoxyl group, a hydroxy group or a mercapto group, and a heterocyclic group, and particularly preferably an organic or inorganic salt of a hydroxy group, a hydroxy group or a mercapto group.

Further, among the substituents of X and W, those having a thioether bond in the substituent are preferable.

Next, specific examples of the compound represented by the general formula [G] are shown below, but the present invention is not limited thereto.

[0086]

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[0087]

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[0088]

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[0089]

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[0090]

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[0091]

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[0092]

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[0093]

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[0094]

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[0095]

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[0096]

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[0097]

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[0098]

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[0099]

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[0100]

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[0101]

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[0102]

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[0103]

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[0104]

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[0105]

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[0106]

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[0107]

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[0108]

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[0109]

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[0110]

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The photothermographic material of the present invention includes hydroxylamine compounds, alkanolamine compounds and ammonium phthalate compounds described in US Pat. No. 5,545,505, and US Pat. No. 5,545,507. Hydroxamic acid compounds; N described in 5,558,983
-Acyl-hydrazine compounds, 5,545,515
Acrylonitrilo compound described in No. 5,937,
No. 449, it is preferable to add a high-contrast accelerator such as a hydrogen atom donor compound such as benzhydrol, diphenylphosphine, dialkylpiperidine or alkyl-β-ketoester. Among them, a quaternary onium compound represented by the following general formula (P) is preferably used.

[0112]

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In the formula, Q represents a nitrogen atom or a phosphorus atom;
Each R _11, R _12, R ₁₃ and R ₁₄ represents a hydrogen atom or a substituent, X ₁ ^- represents an anion. Incidentally, R _{11 to} R ₁₄ may be connected to each other to form a ring.

In the general formula (P), examples of the substituent represented by R _{11 to} R ₁₄ include an alkyl group (eg, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a cyclohexyl group) and an alkenyl group ( Allyl group, butenyl group, etc.),
Alkynyl group (propargyl group, butynyl group, etc.), aryl group (phenyl group, naphthyl group, etc.), heterocyclic group (piperidinyl group, piperazinyl group, morpholinyl group, pyridyl group, furyl group, thienyl group, tetrahydrofuryl group,
Tetrahydrothienyl group, sulfolanyl group, etc.), amino group and the like.

Examples of the ring which can be formed by connecting R _{11 to} R ₁₄ include a piperidine ring, a morpholine ring, a piperazine ring, a quinuclidine ring, a pyridine ring, a pyrrole ring, an imidazole ring, a triazole ring and a tetrazole ring. .

The groups represented by R _{11 to} R ₁₄ may have a substituent such as a hydroxyl group, an alkoxyl group, an aryloxy group, a carboxyl group, a sulfo group, an alkyl group and an aryl group.

R ₁₁ , R ₁₂ , R ₁₃ and R ₁₄ are preferably a hydrogen atom and an alkyl group.

[0118] X _p ^- as represented anion, a halogen ion, sulfate ion, nitrate ion, acetate ion, and inorganic and organic anions, such as p- toluenesulfonic acid ion.

More preferably, the following general formulas (Pa) and (P
a compound represented by b) or (Pc); and a compound represented by the following general formula [T].

[0120]

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In the formula, A ¹ , A ² , A ³ , A ⁴ and A ⁵ represent a group of nonmetal atoms for completing a nitrogen-containing heterocyclic ring, and may contain an oxygen atom, a nitrogen atom and a sulfur atom. And the benzene ring may be condensed. A ¹ , A ² , A ³ , A ⁴ and A ⁵
May have a substituent and may be the same or different. Examples of the substituent include an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a halogen atom, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfo group, a carboxy group, a hydroxy group, an alkoxyl group, and an aryloxy group. Amide group, sulfamoyl group, carbamoyl group, ureido group, amino group, sulfonamide group, sulfonyl group, cyano group, nitro group, mercapto group, alkylthio group and arylthio group. Preferred examples of A ¹ , A ² , A ³ , A ⁴ and A ⁵ include a 5- to 6-membered ring (pyridine,
Imidazole, thiazole, oxazole, pyrazine,
Each ring such as pyrimidine), and a more preferred example is a pyridine ring.

B _P represents a divalent linking group, and m represents 0 or 1. Examples of the divalent linking group include an alkylene group, an arylene group, an alkenylene _{group, -SO 2 -, - SO -} , -
O -, - S -, - CO -, - N (R 6) - (R 6 is an alkyl group, an aryl group, a hydrogen atom) represents what is configured alone or in combination. Preferred examples of B _p include an alkylene group and an alkenylene group.

R ¹ , R ² and R ⁵ each have 1 to 20 carbon atoms
Represents an alkyl group. R ¹ and R ² may be the same or different. The alkyl group represents a substituted or unsubstituted alkyl group, and the substituent is the same as the substituents described as the substituents for A ¹ , A ² , A ³ , A ⁴ and A ⁵ .

Preferred examples of R ¹ , R ² and R ⁵ include:
Each is an alkyl group having 4 to 10 carbon atoms. More preferred examples include an alkyl group substituted with an aryl group.

[0125] X _p ^- represents a counter ion necessary to neutralize the charge of the whole molecule, for example chloride, bromide,
It represents iodine ion, nitrate ion, sulfate ion, p-toluenesulfonate, oxalate and the like. n _p represents the number of counter ions required to neutralize the charge of the whole molecule, and n _p is 0 in the case of an internal salt.

[0126]

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The substituents R ⁶ and R ⁷ of the phenyl group of the triphenyltetrazolium compound represented by the general formula [T],
R ⁸ is preferably a hydrogen atom or a compound having a negative Hammett's sigma value (σP) indicating electron-withdrawing degree.

The Hammett's sigma value at the phenyl group is described in many literatures, for example, Journal of Medical Chemistry.
chemistry, 20, 304, 1977. The group having a particularly preferable negative sigma value is, for example, a methyl group (σP = −0.17 or less, all σP values) and an ethyl group (− 0.15), cyclopropyl group (-0.21), n-propyl group (-0.13), is
o-propyl group (-0.15), cyclobutyl group (-
0.15), n-butyl group (-0.16), iso-butyl group (-0.20), n-pentyl group (-0.1
5), cyclohexyl group (-0.22), amino group (-
0.66), acetylamino group (-0.15), hydroxy group (-0.37), methoxy group (-0.27), ethoxy group (-0.24), propoxy group (-0.2
5), butoxy group (-0.32), pentoxy group (-
0.34), etc., each of which has the general formula [T]
Is useful as a substituent of the compound of

N represents 1 or 2, and examples of the anion represented by X _T ^n- include halogen ions such as chloride ion, bromide ion and iodide ion, nitric acid, sulfuric acid, and the like.
Acid radicals of inorganic acids such as perchloric acid, acid radicals of organic acids such as sulfonic acid and carboxylic acid, anionic activators, specifically p-
Lower alkylbenzene sulfonic acid anions such as toluene sulfonic acid anion; higher alkyl benzene sulfonic acid anions such as p-dodecyl benzene sulfonic acid anion; higher alkyl sulfate anions such as lauryl sulfate anion; boric acid anions such as tetraphenyl boron; Dialkyl sulfosuccinate anions such as 2-ethylhexyl sulfosuccinate anion,
Examples thereof include higher fatty acid anions such as cetyl polyethenoxy sulfate anion, and polymers having an acid radical attached to a polymer such as polyacrylate anion.

Hereinafter, specific examples of the quaternary onium compound will be shown below, but it should not be construed that the invention is limited thereto.

[0131]

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[0132]

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[0133]

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[0134]

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[0135]

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[0136]

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[0137]

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[0138]

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[0139]

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[0140]

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The above quaternary onium compound can be synthesized with reference to a known method. For example, the above tetrazolium compound can be synthesized as described in Chemical Reviews, 55, p. 335
To 483 can be referred to.

The addition amount of these quaternary onium compounds is about 1 × 10 ^-8 to 1 mol, preferably 1 × 10 ^-7 to 1 × 10 ^-1 mol per mol of silver halide. These can be added to the light-sensitive material at any time from the time of silver halide grain formation to the time of coating.

The quaternary onium compound may be used alone or
More than one species may be used in combination. The compound may be added to any of the constituent layers of the photosensitive material, but is preferably added to at least one of the constituent layers on the side having the photosensitive layer, and further to the photosensitive layer and / or a layer adjacent thereto.

The light-sensitive silver halide used in the present invention functions as a light sensor. In the present invention, the average grain size of the silver halide is preferably 0.1 μm or less, more preferably 0.01 μm to 0.1 μm in order to suppress white turbidity after image formation and obtain good image quality. And particularly preferably from 0.02 μm to 0.08 μm.

When the silver halide grains are cubic or octahedral, so-called normal crystals, the grain size refers to the length of the edge of the silver halide grains. In the case of non-normal crystals, for example, in the case of spherical, rod-shaped, or tabular grains, the diameter indicates the diameter of a sphere equivalent to the volume of silver halide grains. Further, the silver halide is preferably monodispersed.

The term “monodispersion” as used herein means a case where the degree of monodispersion determined by the following equation is 40% or less. In the present invention, the monodispersity is more preferably 30% or less, particularly preferably 0.1% or more and 20% or less.

Monodispersity = (standard deviation of particle size) / (average value of particle size) × 100 In the invention, the silver halide particles have an average particle size of 0.1.
μm or less and more preferably monodisperse particles,
Within this range, the graininess 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, more preferably 7%.
It is preferably at least 0%, particularly preferably at least 80%. The ratio of the Miller index [100] plane is determined by the T.M. Tani, J .; Imaging Sci. , 29,
165 (1985).

Another preferred form of photosensitive silver halide is tabular grains. The term “tabular grains” as used herein means those having an aspect ratio = r / h of 3 or more when the thickness in the vertical direction is h μm, where the square root of the projected area is r μm. Among them, the aspect ratio is more preferably 3 or more and 50 or less. The particle size is preferably 0.1 μm or less, more preferably 0.01 μm to 0.08 μm.
μm is preferred. These are disclosed in US Pat. No. 5,264,33.
No. 7, No. 5,314,798, No. 5,320,958
The target tabular grains can be obtained by referring to the above patents.

When these tabular grains are used in the present invention, the sharpness of an image is further improved. The halogen composition is not particularly limited, and may be any of silver chloride, silver chlorobromide, silver chloroiodobromide, silver bromide, silver iodobromide, and silver iodide. AgX particles used in the present invention are P.A. Glafk
by chimes et Physique
Photographique (Paul Monte)
l, 1967); F. Duffin's Ph
autographic Emulsion Chemi
story (published by The Focal Press, 196)
6 years). L. By Zelikman et al M
aking and Coating Photogr
aphic Emulsion (The Focal
Press, 1964) and the like, and can be prepared using an Ag emulsion prepared by a method described in US Pat.

The photosensitive silver halide used in the present invention 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 preferably contains metal ions belonging to groups 6 to 11 of the periodic table. As the above metals, W, Fe, Co,
Ni, Cu, Ru, Rh, Pd, Re, Os, Ir, P
t and Au are preferred.

These metal ions can be introduced into silver halide in the form of a metal complex or a metal complex ion. As these metal complexes or metal complex ions, hexacoordinate metal complexes represented by the following general formula are preferable.

In the formula [ML ₆ ] ^m , M is a transition metal selected from the elements of Groups 6 to 11 of the periodic table, L is a ligand, and m is 0,-, 2-, 3- or 4-
Represents Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and aquo. Ligand, nitrosyl, thionitrosyl and the like, preferably 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), iridium (Ir) and osmium (Os).

Specific examples of transition metal complex ions are shown below, but the present invention is not limited to these.

[0157] 1: [RhCl _6] ^3- 2: [RuCl _6] ^3- 3: [ReCl _6] ^3- 4: [RuBr _6] ^3- 5: [OsCl _6] ^3- 6: [IrCl _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) Cl (CN) 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) Cl _5] ^2- 24: _{[Re (NS) Cl 4 (SeCN} ) ] ^2- 25: [Os (NS) Cl (SCN) 4 ] ^2- 26: [Ir (NO ) Cl ₅ ] ^2-27 : [Ir (NS) Cl ₅ ] ^2- These metal ions, metal complexes or metal complex ions may be of one kind or a combination of two or more of the same and different metals. Is also good. The content of these metal ions, metal complexes or metal complex ions, generally is suitably ¹ × 10 -9 ~1 × 10 ^-2 mol per mol of silver halide, preferably 1 × 10 ^{- It is 8} to 1 × 10 ^-4 mol.

Compounds which provide these metal ions or complex ions are added during silver halide grain formation.
It is preferably incorporated into silver halide grains, and may be added at any stage before and after preparation of silver halide grains, that is, nucleation, growth, physical ripening, and chemical sensitization. It is preferably added at the stage of physical ripening, more preferably at the stage of nucleation and growth, and most preferably at the stage of nucleation.

In the addition, it may be added several times in several 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 grain formation, or a silver salt solution and a halide solution are used. When they are mixed simultaneously, they are added as a third aqueous solution 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 a method in which halogen is added. There is a method in which another silver halide grain doped with metal ions or complex ions in advance during the preparation of 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 during physical ripening, or at the time of chemical ripening.

The silver halide grains used in the present invention may or may not be desalted after grain formation. When desalting is performed, methods known in the art such as a noodle method and a flocculation method are used. Can be desalted by washing with water.

The silver halide grains used in the present invention are preferably chemically sensitized. Preferred chemical sensitization methods are sulfur sensitization, as is well known in the art,
Selenium sensitization and tellurium sensitization can be used. Further, a noble metal sensitization method or a reduction sensitization method of a gold compound, platinum, palladium, an iridium compound or the like can be used. As the compound preferably used in the sulfur sensitization method, the selenium sensitization method, and the tellurium sensitization method, known compounds can be used, and the compounds described in JP-A-7-128768 can be used. Examples of tellurium sensitizers include diacyl tellurides, bis (oxycarbonyl) tellurides,
Bis (carbamoyl) tellurides, diacyl tellurides, bis (oxycarbonyl) ditellurides, bis (carbamoyl) ditellurides, compounds having a P = Te bond, tellurocarboxylates, Te-organyltellurocarboxylates, Use of (poly) tellurides, tellurides, tellurols, telluroacetals, tellurosulfonates, compounds having a P-Te bond, Te-containing heterocycles, tellurocarbonyl compounds, inorganic tellurium compounds, colloidal tellurium, etc. Can be. Compounds preferably used for the noble metal sensitization method include, for example, chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, gold selenide, US Pat. No. 2,448,060, British Patent No. 618,061 and the like. Can be preferably used.

As specific compounds for the reduction sensitization method, in addition to ascorbic acid and thiourea dioxide, for example, stannous chloride, aminoiminomethanesulfinic acid, hydrazine derivatives, borane compounds, silane compounds, polyamine compounds and the like are used. be able to. Further, reduction sensitization can be achieved by ripening the emulsion while maintaining the pH of the emulsion at 7 or more or the pAg at 8.3 or less. Further, reduction sensitization can be achieved by introducing a single addition portion of silver ions during grain formation.

The organic silver salt used in the present invention is a reducible silver source, and is an organic acid containing a reducible silver ion source. Examples of the organic acid used in the present invention include an aliphatic carboxylic acid, a carbocyclic carboxylic acid, a heterocyclic carboxylic acid, and a heterocyclic compound.
An aliphatic carboxylic acid having 0, preferably 15 to 25 carbon atoms) and a heterocyclic carboxylic acid having a nitrogen-containing heterocyclic ring are preferably used. Moreover, when the ligand is 4.0-10.
Organic silver salt complexes having a total stability constant for silver ions of 0 are also useful.

Examples of the silver salt of an organic acid used in the present invention include Research Disclosure No. 170.
And silver salts of fatty acids (eg, silver salts of gallic acid, oxalic acid, behenic acid, arachidic acid, stearic acid, palmitic acid, lauric acid, etc.); Carboxyalkylthiourea salts (eg, 1- (3-carboxypropyl) thiourea, 1- (3-carboxypropyl) -3,3-dimethylthiourea); polymerization reaction products of aldehydes and hydroxy-substituted aromatic carboxylic acids (E.g., aldehydes (formaldehyde, acetaldehyde, butyraldehyde, etc.) and hydroxy-substituted aromatic carboxylic acids (e.g., salicylic acid, benzoic acid, 3,5-dihydroxybenzoic acid, 5,5-thiodisalicylic acid, etc.) Silver complex or the like of a polymerization reaction product of), a silver salt or complex of a thione (for example, 3- (2-carbo) (Silethyl) -4-hydroxymethyl-4-thiazoline-2-thione and 3-carboxymethyl-4-thiazoline-2-thione), imidazole, pyrazole, urazole, 1,2,4-thiazole and 1H-tetrazole, -Amino-5-benzylthio-1,2,4-triazole and benzotriazole, and complexes and salts of silver with nitrogen acids; silver salts such as saccharin and 5-chlorosalicylaldoxime; and silver salts of mercaptides . Among the organic silver salts described above, silver salts of fatty acids are preferably used, and silver behenate, silver arachidate and silver stearate are more preferably used.

The dispersion of the aqueous organic silver salt used in the present invention can be obtained by mixing silver nitrate and an organic acid alkali metal salt. At the same time, silver nitrate and silver halide are added and mixed simultaneously when the organic silver salt is formed. It is preferably produced using a mixing method.

For example, an organic acid alkali metal salt soap (eg, sodium behenate, sodium arachidate, etc.) is prepared by adding an alkali metal hydroxide (eg, sodium hydroxide, potassium hydroxide, etc.) to an organic acid. By using a controlled double jet method, silver nitrate and silver halide can be simultaneously added and mixed to prepare an aqueous organic silver salt dispersion used in the present invention.

Further, the aqueous organic silver salt dispersion used in the present invention can be prepared by a so-called controlled triple jet method in which an alkali metal salt of an organic acid, silver nitrate and silver halide are simultaneously added and mixed, respectively. it can.

In the present invention, the method for producing an aqueous organic silver salt dispersion using the above-described controlled double jet method is preferably used from the viewpoint of simplicity in the production process. From the viewpoint of producing a high-sensitivity photothermographic material, the method for producing an aqueous organic silver salt dispersion using the above-described controlled triple jet method is preferably used.

The photothermographic material of the present invention contains a reducing agent. Examples of suitable reducing agents are described in US Pat. No. 3,770,4.
No. 48, No. 3,773, 512, No. 3,593,
No. 863 and Research Disclosur
e, Nos. 17029 and 29996, and include: Aminohydroxycycloalkenonone compounds (eg, 2-hydroxypiperidino-2-cyclohexenone); aminoreductones esters (eg, piperidinohexose reductone monoacetate) as precursors of reducing agents; N- Hydroxyurea derivatives (for example, Np-methylphenyl-N
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 (for example, benzenesulfhydroxamic acid); sulfonamidoanilines (for example, 4- (N-methanesulfonamido) aniline); 2-tetrazoli Ruthiohydroquinones (eg, 2-methyl-5- (1-phenyl-5-tetrazolylthio) hydroquinone); tetrahydroquinoxalines (eg, 1,2,3,4-tetrahydroquinoxaline); Sims (e.g., phenylamidoxime, 2-thienylamidoxime); Azines (e.g., a combination of aryl hydrazides of aliphatic carboxylic acids and ascorbic acid); Combinations of polyhydroxybenzene and hydroxylamine, reductone and / or hydrazine Hydroxamic 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; Phenylindan-1,3-dione and the like; chroman; 1,4-dihydropyridines (for example, 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
l), 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. Examples of the hindered phenols include compounds represented by the following general formula (A).

[0172]

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In the formula, R is a hydrogen atom or a group having 1 to 1 carbon atoms.
Represents an alkyl group of 10 (eg, butyl group, 2,4,4-trimethylpentyl group, etc.), and R ′ and R ″ represent an alkyl group having 1 to 5 carbon atoms (eg, methyl group, ethyl group, t- Butyl group).

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

[0175]

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[0176]

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The amount of the reducing agent including the compound represented by the formula (A) is preferably 1 × 1 per mol of silver.
It is from 0 ^-2 to 10 mol, especially from 1 x 10 ^{-2 to} 1.5 mol.

The photothermographic material of the present invention may contain an antifoggant. Known as an effective antifoggant is mercury ion, and the use of a mercury compound as an antifoggant in a light-sensitive material is disclosed in, for example, US Pat. No. 3,589,903. However, mercury compounds are environmentally unfavorable and are, for example, disclosed in U.S. Patent Nos. 4,546,075 and 4,452.
Non-mercury antifoggants such as those disclosed in JP-A-885-85 and JP-A-59-57234 are preferably used in the present invention.

Particularly preferred non-mercury antifoggants include US Pat. Nos. 3,874,946 and 4,753.
No. 6,999, the compound -C (X
₁ ) Heterocyclic compounds having at least one substituent represented by (X ₂ ) (X ₃ ) (where X ₁ and X ₂ each represent a halogen atom, and X ₃ represents hydrogen or a halogen atom). Can be

Other suitable antifoggants include paragraph No. [0030] of JP-A-9-288328.
To [0036], JP-A-9-9
Compounds described in paragraph Nos. [0062] to [0063] of US Pat. No. 0550, US Pat. No. 5,028,523 and European Patent Nos. 600,587 and 605,981.
Nos. 631,176 and the like can be used.

It is preferable to add a toning agent to the photothermographic material of the present invention for the purpose of improving the silver tone after development. Examples of suitable toning agents are Research Discl
No. 17029, which includes the following:

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 photobleaches (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 Combinations of acids; phthalazine (including adducts of phthalazine) and maleic anhydride, and phthalic acid, 2,3-naphthalenedicarboxylic acid or o-phenylene acid derivatives and anhydrides thereof (for example,
Combination with at least one compound selected from phthalic acid, 4-methylphthalic acid, 4-nitrophthalic acid and tetrachlorophthalic anhydride; quinazolinediones, benzoxazine, naloxazine 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-dimercapto-1,4-diphenyl-1H, 4
H-2,3a, 5,6a-tetraazapentalene). Preferred toning agents are phthalazone or phthalazine.

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-6-259351.
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
17643 IV-A (p. 23, December 1978), and Item 18431 (p. 437, August 1979), etc. 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-9-806
The compounds described in No. 79 are preferably used.

In the present invention, an aromatic or heteroaromatic mercapto compound, a disulfide compound or the like is used in order to control the development by suppressing or accelerating the development, to improve the spectral sensitization efficiency, and to improve the storage stability before and after the development. , A thione compound.

As the mercapto compound used in the present invention, those represented by Ar-SM and Ar-SS-Ar are preferable. In the formula, M is a hydrogen atom or an alkali metal atom, and Ar represents an aromatic ring or a heteroaromatic ring having one or more nitrogen, sulfur, oxygen, selenium or tellurium atoms.

In the present invention, a heteroaromatic ring is preferably used. As the heteroaromatic ring, for example, benzimidazole, naphthimidazole, benzothiazole, naphthothiazole, benzoxazole, naphthoxazole, benzoselenazole, benzotellurazole, imidazole, oxazole, pyrazole, triazole,
Thiadiazole, tetrazole, triazine, pyrimidine, pyridazine, pyrazine, pyridine, purine, quinoline or quinazolinone. The heteroaromatic ring includes, for example, a halogen atom (for example, Br and Cl), a hydroxy group, an amino group, a carboxy group, an alkyl group (for example, one or more carbon atoms, preferably 1 to 4 carbon atoms). And an alkoxyl group (for example, 1
At least one carbon atom, preferably one having 1 to 4 carbon atoms). As mercapto-substituted heteroaromatic compounds,
2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole,
2-mercapto-5-methylbenzothiazole, 3-mercapto-1,2,4-triazole, 2-mercaptoquinoline, 8-mercaptopurine, 2,3,5,6-tetrachloro-4-pyridinethiol, 4- Hydroxy-
Examples thereof include 2-mercaptopyrimidine and 2-mercapto-4-phenyloxazole, but the present invention is not limited thereto.

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. Is preferably contained in a weight ratio of 0.5 to 30% based on 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 the inorganic substance, Swiss Patent No. 3
Silica described in No. 30,158, French Patent No. 1,29
No. 6,995, etc., British Patent No. 1,17
Alkaline earth metals or carbonates such as cadmium and zinc described in 3,181 and the like can be used as a matting agent. As organic substances, US Pat. No. 2,322,03
7, starch derivatives described in Belgian Patent No. 625,451 and British Patent No. 981,198, polyvinyl alcohol described in Japanese Patent Publication No. 44-3643, and Swiss Patent No. 330,158. Polystyrene or polymethacrylate described in U.S. Pat.
Organic matting agents such as polyacrylonitrile described in No. 79,257 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 sphere. 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 matting agent has a coefficient of variation of the particle size distribution of preferably 50% or less, more preferably 40% or less, and particularly preferably 30% or less.

Here, the coefficient of variation 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 used in the present invention can be contained in any constituent layer, but in order to achieve the object of the present invention, It is preferably a constituent layer other than the photosensitive layer, and more preferably the outermost layer as viewed from the support.

The method for adding the matting agent used in the present invention may be a method in which the matting agent is dispersed in a coating solution in advance and the matting agent may be sprayed after the coating solution 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.

In the present invention, a conductive compound such as a metal oxide and / or a conductive polymer can be contained in the constituent layer in order to improve the chargeability. These may be contained in any layer, but are preferably contained in an undercoat layer, a backing layer, a layer between the photosensitive layer and the undercoat, and the like.

In the present invention, US Pat.
The conductive compounds described in No. 773 columns 14 to 20 are preferably used.

Various additives may be added to any of the photosensitive layer, the non-photosensitive layer, and other constituent 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 in addition to the above. These additives and the other additives mentioned above are used in Research Disclosure.
re Item 17029 (June 1978, p. 9-
The compound described in 15) can be preferably used.

Binders suitable for the photothermographic material of the present invention 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 (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). It may be hydrophilic or non-hydrophilic. In order to protect the surface of the light-sensitive material and prevent abrasion, a non-light-sensitive layer may be provided outside the light-sensitive layer. The binder used for these non-photosensitive layers may be the same as or different from the binder used for the photosensitive layers.

In the present invention, the amount of the binder is 5 to 90 wt% of the total amount of the material on the photosensitive layer side including the photosensitive layer and the protective layer.
%, Preferably 0.5 to 20 g / m ² , and the same range is preferably used for the back layer. The total weight including binder and each material is 1 to 1 per side
30 g / m ² is preferred.

Further, in the present invention, in order to increase the speed of thermal development, the amount of binder in the photosensitive layer is 1.5 to 10 g / g.
m ² is preferred. More preferably 1.7 to
8 g / m ² .

The support used in the present invention may be a plastic film (for example, polyethylene terephthalate, polycarbonate, or the like) for preventing image deformation after the development processing.
Polyimide, nylon, cellulose triacetate, polyethylene naphthalate) are preferred.

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 about 50 to 300 μm, preferably 70 to 180 μm.

A heat-treated plastic support 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.
It is preferable to heat 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, and 5-sodium sulfo acid are used as acid components. A polyester containing a modified polyester component of isophthalic acid, adipic acid or the like and a glycol component such as ethylene glycol, propylene glycol, butanediol, cyclohexanedimethanol or the like in an amount of 10 mol% or less of the entire 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 of forming a support and the method of producing an undercoat used in the present invention, known methods can be used, and preferably, paragraph [0030] of JP-A-9-50094 is used.
To [0070].

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 photosensitive silver halide, a reducing agent and, if necessary, silver. It is preferable that the photothermographic material contains a color toning agent which suppresses the color tone of the present invention 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 exposed to high temperature (for example,
(0 ° C.). Heating generates 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. 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. 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. To control the amount or wavelength distribution of light passing through the photosensitive layer, a filter dye layer on the same side as the photosensitive layer and / or an antihalation dye layer, a so-called backing layer, may be formed on the opposite side. A dye or pigment may be included in the active layer. As the dye to be used, any compound may be used as long as it has a desired absorption in a desired wavelength range, and examples thereof include JP-A-59-6481 and JP-A-59-1.
No. 82436, U.S. Pat. No. 4,271,263, U.S. Pat. No. 4,594,312, European Patent Publication 533,0
08, European Patent Publication 652,473, JP-A-2-2-2
No. 16140, JP-A-4-348339, JP-A-7-
Compounds described in JP-A-191432 and JP-A-7-301890 are preferably used.

These non-photosensitive layers preferably contain the binder or matting agent described above, and may further contain a slip agent such as a polysiloxane compound, wax or liquid paraffin.

The light-sensitive layer may be composed of a plurality of layers, and the sensitivity may be changed to a high-sensitive layer / low-sensitive layer or a low-sensitive layer / high-sensitive layer for adjusting the gradation.

The details of the photothermographic material are described in, for example, US Pat. Nos. 3,152,904 and 3,457,
No. 075, and D.A. “Dry Silver Photographic Materials (Dry Silver P) by Morgan
photographic Material) ”and D.C.
Morgan and B.A. Shelley
y) "Heat treated silver system (The
rally Processed Silver S
systems) "(Imaging Processes and Materials)
es and Materials) Neblette
Eighth Edition, Sturge, V.S. Walworth, A .; Shep
p) Edit, page 2, 1969).
Among them, in the present invention, the photosensitive material is 80 to 140
It is characterized in that an image is formed by heat development at a temperature of ° C. and no fixing is performed. Therefore, the silver halide and the organic silver salt remaining in the unexposed area remain in the photosensitive material without being removed.

In the present invention, after the heat development,
The optical transmission density of the light-sensitive material containing the support at 400 nm is preferably 0.2 or less. A more preferable value of the optical transmission density is 0.02 or more and 0.2 or less.

[0215]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but it should not be construed that the invention is limited thereto.

Example 1 <Preparation of PET support> PET pellets were
After drying for an hour, it was melted at 300 ° C., extruded from a T-die, and quenched to prepare an unstretched film. This was longitudinally stretched 3.0 times using rolls having different peripheral speeds, and then horizontally stretched 4.5 times using a tenter. The temperatures at this time were 110 ° C. and 130 ° C., respectively. After this, 240 ° C
After heat setting for 20 seconds, the film was relaxed 4% in the horizontal direction at the same temperature. Thereafter, the chuck portion of the tenter was slitter, and both ends were knurled and wound at 4 kg / cm ² . Thus, a roll of a PET film having a width of 2.4 m, a length of 800 m and a thickness of 100 μm was obtained. PET also had a glass transition point of 79 ° C.

A biaxially stretched heat-fixed PET film support having a thickness of 100 μm and having a thickness of 100 μm was subjected to a corona discharge treatment of 8 W / m ² · min.
On one surface, the following undercoating coating solution a-1 was dried to a thickness of 0.8 μm.
And then dried to form an undercoat layer A-1. On the other side, an undercoat coating solution b-1 which has been subjected to the following antistatic treatment is applied so as to have a dry film thickness of 0.8 μm. The resultant was dried to obtain an antistatic subbing layer B-1.

<< Undercoat Coating Solution a-1 >> Co-weight of butyl acrylate (30% by weight), t-butyl acrylate (20% by weight), styrene (25% by weight), and 2-hydroxyethyl acrylate (25% by weight) Combined latex liquid (solid content 30%) 270 g (C-1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Polystyrene fine particles (average particle size 3 μm) 0.05 g Colloidal silica (average particle size) (90 μm) 0.1 g Finished to 1 liter with water << Undercoat coating solution b-1 >> SnO ₂ / Sb (9/1 weight ratio, average particle size 0.18 μm) Amount to become 200 mg / m ² Butyl acrylate (30 weight %), Styrene (20% by weight), glycidyl acrylate (40% by weight) copolymer latex liquid (solid content 30%) 270 g (C-1) .6g hexamethylene-1,6-bis (ethyleneurea) subsequently finished in 0.8g water to 1 liter, the undercoat layer A-1 and the upper surface undercoat layer B-1,
A corona discharge of 8 W / m ² · min. Was performed, and the following lower coating liquid a-2 was coated on the lower coating layer A-1 with a dry film thickness of 0.1 μm.
The lower coating layer B-2 is coated with the following coating liquid b-2 on the lower coating layer B-1 so as to have a dry film thickness of 0.8 μm. Coated as B-2.

<< 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 Finished to 1 liter with water << Lower coating solution for upper layer b-2 >> (C-4) 60 g Latex liquid containing (C-5) as a component (solid content: 20%) 80 g Ammonium sulfate 0 0.5 g (C-6) 12 g Polyethylene glycol (weight average molecular weight 600) 6 g Finish to 1 liter with water

[0220]

Embedded image

[0221]

Embedded image

(Heat Treatment of Support) In the above-mentioned undercoat drying step of the five types of undercoated support, the support was heated at 140 ° C. and then gradually cooled.

(Preparation of silver halide emulsion A) 900 m of water
7.5 g of inert gelatin and 10 ml of potassium bromide
mg, and adjusted to a temperature of 35 ° C. and a pH of 3.0, and 370 ml of an aqueous solution containing 74 g of silver nitrate (60/3
8/2) molar ratio of sodium chloride, potassium bromide and potassium iodide (equimolar to silver nitrate) and K ₂ [Ir (N
Added O) Cl _5] per mole silver 1 × 10 ^-6 mol and aqueous rhodium chloride salt containing 1 × 10 ^-6 mol per mol of silver 370 ml, by the controlled double jet method while maintaining the pAg7.7 did. Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added, the pH was adjusted to 8 with NaOH, and the pAg was adjusted to 6.5 to perform reduction sensitization. The coefficient of variation of the projected diameter area with a dispersion degree of 10% is 8%, [10
0] Cubic silver iodobromide grains having an area ratio of 87% were obtained. This emulsion was subjected to coagulation sedimentation using a gelatin coagulant and desalting treatment, followed by addition of 0.1 g of phenoxyethanol, pH 5.9, pA
g was adjusted to 7.5 to obtain silver halide emulsion A.

(Preparation of Na Behenate Solution) In 945 ml of pure water, 32.4 g of behenic acid, 9.9 g of arachidic acid and 5.6 g of stearic acid were dissolved at 90 ° C. Next, while stirring at a high speed, 98 ml of a 1.5 M aqueous sodium hydroxide solution
Was added. Next, 0.93 ml of concentrated nitric acid was added.
C. and stirred for 30 minutes to obtain a sodium behenate solution.

(Preparation of Preform Emulsion of Silver Behenate and Silver Halide Emulsion A) 15.1 g of the silver halide emulsion A was added to the above sodium behenate solution, and the pH was adjusted to 8.1 with a sodium hydroxide solution. Later, 1M silver nitrate solution 14
7 ml was added over 7 minutes, the mixture was further stirred for 20 minutes, and water-soluble salts were removed by ultrafiltration. The resulting silver behenate was grains having an average grain size of 0.8 μm and a monodispersity of 8%. After the floc of the dispersion has formed, the water is removed and an additional 6
After washing with water and removing water several times, it was dried.

(Preparation of Photosensitive Emulsion) The preform emulsion thus prepared was divided into 、, and 544 g of a methyl ethyl ketone solution (17 wt%) of polyvinyl butyral (average molecular weight: 3000) and 107 g of toluene were gradually added and mixed. Later, the medium was dispersed at 4000 psi using a 0.5 mm size ZrO2 bead mill.
The dispersion was performed at 10 ° C. for 10 minutes.

The following layers were simultaneously coated on both sides of the support to prepare samples. The drying was performed at 60 ° C. for 15 minutes.

(Back surface side coating) A liquid having the following composition was coated on layer B-1 of the support.

Cellulose acetate butyrate (10% methyl ethyl ketone solution) 15 ml / m ² dye-A 7 mg / m ² dye-B 7 mg / m ² Matting agent: monodispersity 15% average particle size 8 μm monodisperse silica 90 mg / m ² _{C 8 F 17 (CH 2 CH} 2 O) 12 C 8 F 17 50mg / m 2 C 9 F 17 -C 6 H 4 -SO 3 Na 10mg / m 2

[0230]

Embedded image

(Coating on Photosensitive Layer Side) Photosensitive Layer 1: A solution having the following composition was coated on layer A-1 of the support so that the coated silver amount was 2.4 g / m ² .

The above-mentioned photosensitive emulsion 240 g Sensitizing dye (0.1% methanol solution) 1.7 ml Pyridinium bromide perbromide (6% methanol solution) 3 ml Calcium bromide (0.1% methanol solution) 1.7 ml Oxidizing agent (10% methanol solution) 1.2 ml 2-4-chlorobenzoylbenzoic acid (12% methanol solution) 9.2 ml 2-mercaptobenzimidazole (1% methanol solution) 11 ml tribromomethylsulfoquinoline (5% methanol solution) 17 ml Hydrazine derivative H-26 0.4 g High-contrast enhancer P-51 0.3 g Phthalazine 0.6 g Compound described in general formula (1) or (2) shown in Table 1 Amount shown in Table 1 4-methylphthalic acid 0. 25 g Tetrachlorophthalic acid 0.2 g Calcium carbonate 0.1 g with an average particle size of 3 μm , 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -2 - methylpropane (20% methanol solution) 20.5 ml isocyanate compound (Mobay Corp., Desmodur N3300) 0.5 g

[0233]

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Surface protective layer: A solution having the following composition was coated simultaneously on the photosensitive layer.

[0235] Acetone 5 ml / m ² methyl ethyl ketone 21 ml / m ² Cellulose acetate butyrate 2.3 g / m ² methanol 7 ml / m ² phthalazine 250 mg / m ² Matting agent: monodisperse degree of 10% average particle size 4μm monodisperse silica 5mg / m ² CH ₂ ＣＨCHSO ₂ CH ₂ CH ₂ OCH ₂ CH ₂ SO ₂ CH ＝ CH ₂ 35 mg / m ² Fluorinated surfactant C ₁₂ F ₂₅ (CH ₂ CH ₂ O) ₁₀ C ₁₂ F ₂₅ 10 mg / m ² _{C 8 F 17 -C 6 H 4} -SO 3 Na 10mg / m 2 using a sample after film formation, where after removal of the binder was measured by an electron microscope with a replica method,
The organic silver particles have a monodispersity of 5% in which tabular grains having a major axis diameter of 0.5 ± 0.05 μm, a minor axis diameter of 0.4 ± 0.05 μm, and a thickness of 0.01 μm are 90% of all organic silver particles. Particles.

<< Exposure and Development >> 810 n as a light source
1.5 × with a laser sensitometer using a semiconductor laser
Step exposure is performed while changing the amount of light in 10 ^-7 seconds.
The film was thermally developed at 0 ° C. for 15 seconds. At that time, exposure and development were performed in a room conditioned at 23 ° C. and 50% RH.

(Evaluation of Fog and Density) Fog: A non-exposed processed sample was subjected to UV irradiation of X-Rite.
Mode.

Density: P for the obtained developed sample
The blackening density was measured with DA-65 (Konica Digital Densitometer).

(Evaluation of Sensitivity) The sensitivity at the concentration of the sample 100 of 2.5 was set as 100 and the relative sensitivity was shown.

(Evaluation of gamma) Gamma is represented by the tangent of density 0.1 and 3.0, and it is shown that a super-high contrast image can be obtained only when the gamma value in the table is 10 or more.

(Evaluation of Storage Property) A film sample was prepared at 50 ° C.
A sample stored for 1 day in an environment of 50% RH was compared with a fresh sample on the same day (fresh). Table 1 shows the results of the evaluation.

[0242]

[Table 1]

Example 2 In Example 1, the general formulas (1) and (2) shown in Table 1 were used.
A sample was prepared and evaluated in the same manner as in Example 1, except that a silver complex of the compound was added as shown in Table 2 instead of the described compound. Table 2 shows the results.

[0244]

[Table 2]

Example 3 In Example 1, a compound represented by the general formula (3) or (4) or a comparative compound shown below was used instead of the compound represented by the general formula (1) or (2). Is Example 1
A sample was prepared in the same manner as described above, and the same evaluation was performed. Table 3 shows the results.

[0246]

[Table 3]

[0247]

Embedded image

Example 4 A sample was prepared in the same manner as in Example 3 except that a silver complex of the compound was added as shown in Table 4 in place of the compound shown in Table 3, and a sample was prepared. Was evaluated.
Table 4 shows the results.

[0249]

[Table 4]

[0250]

By using a phosphazene compound or an amino acid having a mercapto group or a silver complex compound thereof, high sensitivity, low fog, excellent preservability, high density image can be obtained, and ultra-high contrast halftone dots can be obtained. A heat-developable photographic material having excellent reproducibility can be provided.

Claims (7)

[Claims] 1. A photothermographic material comprising a light-sensitive silver halide, an organic silver salt, a reducing agent and a high contrast agent,
A photothermographic material comprising at least one compound represented by the following general formula (1) or (2). Embedded image [Wherein R ₁ and R ₂ each represent an alkyl group, an alkoxy group, an aryloxy group, an aryl group, an isothiocyanate group,
Represents an amino group, an alkylthio group, an arylthio group, an azido group, or a derivative thereof, and R ₁ and R ₂ may be the same or different. n1 represents a positive integer of 1 or more, and when n1 is 2 or more, a plurality of R ₁ and R ₂ may be the same or different. [Chemical formula 2] [Wherein, R _1, R ₂ is, R ₁ of each above-mentioned general formula (1), R ₂
And R ₁ and R ₂ may be the same or different. n2 represents a positive integer of 3 or more;
₁ and R ₂ may be the same or different. ] 2. A photothermographic material comprising a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent,
A photothermographic material comprising at least one silver complex salt of the compound represented by formula (1) or (2). 3. A photothermographic material comprising a light-sensitive silver halide, an organic silver salt, a reducing agent and a high contrast agent,
A photothermographic material comprising at least one compound represented by the following general formula (3) or (4). Embedded image [In the formula, R ₃ and R ₄ represent a hydrogen atom and an alkyl group having 1 to 3 carbon atoms. However, R ₃ and R ₄ are not simultaneously hydrogen atoms. R ₅ and R _{6 each} represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₇ represents a hydroxyl group, an amino group or
Represents up to 3 alkyl groups. R _8, R ₉ represents a hydrogen atom, an alkyl group having up to 5 carbon atoms, an acyl group or a -COOM ₂ group up to 18 carbon atoms. However, R ₈ and R ₉ are not hydrogen atoms at the same time. M ₁ represents a hydrogen atom, an alkali metal atom, or an ammonium group. M ₂ represents a hydrogen atom, an alkyl group having up to 4 carbon atoms, an alkali metal atom, an aryl group, an aralkyl group having up to 15 carbon atoms. m is 0,
Represents 1 or 2. ] 4. A photothermographic material comprising a photosensitive silver halide, an organic silver salt, a reducing agent and a contrast agent,
A photothermographic material comprising at least one silver complex salt of the compound represented by formula (3) or (4). 5. The photothermographic material according to claim 1, wherein the photosensitive layer or a layer adjacent thereto contains a hydrazine derivative. 6. The composition according to claim 1, which comprises at least one kind of an amine compound or a quaternary onium compound.
6. The photothermographic material according to any one of the above items 5. 7. The photothermographic material according to claim 1, wherein a high-contrast image having a gamma of 10 or more is formed.