JP2000318321A - Heat-sensitive recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a violet to cyan coloring type diazo heat-sensitive recording material which is excellent in shelf life, image preservation property and image fixing property, and of which the hue is improved. SOLUTION: In this heat-sensitive recording material wherein on a supporting body, a heat-sensitive recording layer containing a diazonium salt compound and a coupler, is provided, in the heat-sensitive recording layer, a pyrolotriazinone compound represented by a formula is contained as the coupler. In the formula, R1 and R2 each represent a hydrogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a substituted carbamoyl group, an alkoxy carbonyl group, an aryloxy carbonyl group, a substituted amino group, an alkyl sulfonyl group, an aryl sulfonyl group, or a substituted sulfamoyl group, and R3 represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an acyl group, an alkoxy carbonyl group, a substituted amino group, a hydroxy group, an alkoxy group, an aryloxy group, a mercapto group, an alkylthio group or an arylthio group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording material using a diazonium salt compound and a coupler as a color-forming component, and more particularly to a novel violet having excellent shelf life, image storability and image fixability and improved hue. To provide a cyan coloring type diazo thermosensitive recording material.

[0002]

2. Description of the Related Art As the performance of thermosensitive recording materials has improved, purple
There is a strong demand for a heat-sensitive recording material which has a cyan coloring property and has a long shelf life of the recording material, improved image storability and image fixability. A diazonium salt compound is a compound having a very high chemical activity, and easily reacts with a compound called a coupler such as a phenol derivative or a compound having an active methylene group to form an azo dye, and also has photosensitivity, Decomposes on light irradiation and loses its activity. For this reason, diazonium salt compounds have long been used as optical recording materials typified by diazocopy ("Photographic Engineering Fundamentals: Non-Silver Salt Photography", edited by the Photographic Society of Japan).
Corona (1982) 89-117, pp. 182-201).

Further, by utilizing the property of decomposing by light and losing activity, it has recently been applied to recording materials requiring fixing of an image. As a typical example, a diazonium salt compound and a coupler are heated in accordance with an image signal. A photo-fixing type thermosensitive recording material has been proposed in which an image is formed by reacting and forming an image, and then irradiating the image with light to fix the image. ~ 29
6 pages).

However, in these recording materials using a diazonium salt compound as a color-forming element, the activity of the diazonium salt compound is extremely high, and even in a dark place, the diazonium salt compound gradually decomposes and loses reactivity. Therefore, there is a disadvantage that the shelf life as a recording material is short. As one of means for improving this drawback, there is a method of encapsulating a diazonium salt compound in microcapsules. According to this method, the diazonium salt compound is
It can be isolated from substances that promote decomposition, such as water and base, and can dramatically improve shelf life as a recording material (Masamasa Usami et al. Journal of the Institute of Electrophotographic Studies Vol. 26, No. 2) No. (1987) 115-1
25).

[0005] When the microcapsules have a glass transition temperature like a urea resin or a urethane resin and have walls whose glass transition temperature is slightly higher than room temperature, the capsule walls at room temperature have a material impermeability. On the other hand, it shows substance permeability above the glass transition temperature, so that it is called a thermoresponsive microcapsule and is useful for a thermosensitive recording material. That is, by preparing a recording material on which a thermoresponsive recording layer containing a thermoresponsive microcapsule containing a diazonium salt compound and a coupler and a base containing a diazonium salt compound is prepared, the diazonium salt compound is stably held for a long period of time. In addition to being able to form a colored image easily by heating, the image can be fixed by light irradiation. As described above, the stability of a diazonium salt compound can be significantly improved by microencapsulation.

On the other hand, 2-hydroxy-3-naphthoic acid anilides show particularly excellent performance as a heat-sensitive recording color-forming material, and when subjected to a coupling reaction with a 4-substituted amino-2-alkoxybenzenediazonium salt compound. Is
It is known to produce a blue dye (Japanese Patent Laid-Open No. 2-2
No. 25082).

However, 2-hydroxy-3-naphthoic anilides have a λma at longer wavelengths than 4-substituted amino-2-alkoxybenzenediazonium salt compounds.
When a diazonium salt compound having x is used, there is a disadvantage that the raw preservability of the recording material (the background coloring during pre-copy preservation) is reduced. Further, for a diazonium salt compound having λmax on the shorter wavelength side, the use of the coupler hinders the fixability of an image upon light irradiation, and has a drawback of increasing the hue to cyan in terms of hue, Further, there is a disadvantage that the storage stability (light fastness) of the color image is not sufficient. As described above, at present, a heat-sensitive recording material having a favorable hue in the color range of purple to cyan and satisfying excellent shelf life, image storability and image fixability has not yet been obtained.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above situation, and is a novel purple-cyan color developing type having excellent shelf life, image storability and image fixability, and improved hue. It is an object of the present invention to provide a diazo thermosensitive recording material.

[0009]

Means for Solving the Problems In order to achieve the above object, the present inventors have paid particular attention to couplers and further to diazonium salt compounds, and as a result of intensive studies, it has been found that the heat-sensitive recording material obtained by the following means is a shelf-sensitive material. The inventors have obtained new findings that they have excellent life, image storability, and image fixability, and have good hues in a color range from purple to cyan, and have completed the present invention. That is, the heat-sensitive recording material of the present invention is a heat-sensitive recording material provided with a heat-sensitive recording layer containing a diazonium salt compound and a coupler which reacts with the diazonium salt compound when heated to form a color on a support. Wherein at least one kind of a pyrrolotriazine-one compound represented by the following general formula (1) is contained.

[0010]

Embedded image

(Wherein R ¹ and R ² each represent a hydrogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a substituted carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted amino group, an alkylsulfonyl group Represents an arylsulfonyl group or a substituted sulfamoyl group, and R ³ represents a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an acyl group, an alkoxycarbonyl group, a substituted amino group, a hydroxy group, an alkoxy group, an aryloxy group, Represents a mercapto group, an alkylthio group, or an arylthio group.)

In the heat-sensitive recording material of the present invention, the hue,
From the viewpoint of optical fixing property, the maximum absorption wavelength λmax is 450n.
m or less, and more preferably a diazonium salt compound represented by the following general formula (2) or / and (3) or / and (4).

[0013]

Embedded image

(Wherein, Ar represents a substituted or unsubstituted aryl group, and R ¹¹ and R ¹² each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹¹ , R ¹² It may be the same, or may be different .X ^- represents an acid anion).

[0015]

Embedded image

(Wherein, R ¹⁴ , R ¹⁵ and R ¹⁶ each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹⁴ , R ¹⁵ and R ¹⁶ may be the same. And Y may be a hydrogen atom or-
OR ¹³ represents a group. R ¹³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. X ^-
Represents an acid anion. )

[0017]

Embedded image

(In the formula, R ¹⁷ and R ¹⁸ each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. X ⁻ represents an acid anion.)

Further, from the viewpoint of raw storage stability and the like, it is preferable that the diazonium salt compound is encapsulated in the microcapsule, and the capsule wall of the microcapsule encapsulating the diazonium salt compound has a polyurethane and / or polyurea component. Preferably, the capsule wall contains.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The coupler used in the present invention is a compound represented by the general formula (1). Where R ¹ and R
² represents a hydrogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a substituted carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted amino group, an alkylsulfonyl group, an arylsulfonyl group, or a substituted sulfamoyl group, respectively. And R ³ represent a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an acyl group, an alkoxycarbonyl group, a substituted amino group, a hydroxy group, an alkoxy group, an aryloxy group, a mercapto group, an alkylthio group, or an arylthio group, respectively. . Among them, R ¹ and R ² are the substituents represented by
^At least one of ¹ and R ² is preferably an electron-withdrawing group having a Hammett's substituent constant σ _P value of 0.20 or more, and at least one of R ¹ and R ² has a value of σ _P More preferably, it is an electron-withdrawing group of 0.35 or more.

Among the electron-withdrawing groups having a σ _P value of 0.20 or more, a cyano group (σ _P value of 0.66) and a perfluoroalkyl group (for example, a trifluoromethyl group having a σ _P value of 0.5)
4), an acyl group (for example, an acetyl group σ _P value of 0.50,
Preferable examples include a benzoyl group (σ _P value of 0.43) and a carbamoyl group (σ _P value of 0.36), but are not limited thereto.

Among the substituents of R ^{1 to} R ³ , the aryl group is
Further, an alkyl group, an alkoxy group, an aryloxy group,
Halogen atom, nitro group, cyano group, substituted carbamoyl group, substituted sulfamoyl group, substituted amino group, substituted oxycarbomoyl group, substituted oxysulfonyl group, alkylthio group, arylthio group, alkylsulfonyl group, arylsulfonyl group, aryl group, hydroxy It may be substituted with a group, an acyl group, an acyloxy group, a substituted sulfonyloxy group, a substituted aminocarbonyloxy group, or a substituted phosphoryloxy group.

The aryl group has 6 to 30 carbon atoms.
Are preferred, for example, a phenyl group, a 2-methylphenyl group, a 2-chlorophenyl group, a 2-methoxyphenyl group, a 2-ethoxyphenyl group, a 2-propoxyphenyl group, a 2-isopropoxyphenyl group, and a 2-butoxy group Phenyl group, 2- (2-ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 2-undecyloxyphenyl group, 2-trifluoromethylphenyl group, 2- (2-ethylhexyloxy) -5-chlorophenyl group 2,2'-hexyloxy-3,5-dichlorophenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 2- (dibutylaminocarbonylethoxy) phenyl group, 2,4-dichlorophenyl Group, 2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group , 3-chlorophenyl group, 3-nitrophenyl group, 3-cyanophenyl group, 3-trifluoromethylphenyl group, 3-methoxyphenyl group, 3-ethoxyphenyl group, 3-butoxyphenyl group, 3-
(2′-ethylhexyloxy) phenyl group, 3,4-
Cyclochlorophenyl group, 3,5-dichlorophenyl group,
3,4-dimethoxyphenyl group, 3,5-dibutoxyphenyl group, 3-octyloxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 3- (di-2-ethylhexylaminocarbonylmethoxy) phenyl group, 3-dodecyloxyphenyl group, 4-chlorophenyl group, 4-cyanophenyl group, 4-nitrophenyl group, 4-trifluoromethylphenyl group, 4-methoxyphenyl group, 4-ethoxyphenyl group, 4-isopropoxyphenyl group , 4-butoxyphenyl group, 4- (2-
Ethylhexyloxy) phenyl group, 4-isopentyloxyphenyl group, 4- (octadecyloxy) phenyl group, 4-benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylsulfonylphenyl group, 4-ethoxy Carbonylphenyl group, 4- (2-ethylhexyloxycarbonyl) phenyl group, 4-t-
Octylphenyl group, 4-fluorophenyl group, 3-acetylphenyl group, 2-acetylaminophenyl group,
2,4-di-t-pentylphenyl group, 4- (2-ethylhexyloxy) carbonylphenyl group, 4-methylthiophenyl group, 4- (4-chlorophenylthio) phenyl group, besides hydroxyphenyl group, phenylsulfonyl Examples include a phenyl group, a phenylsulfonyloxyphenyl group, a phenylcarbonyloxyphenyl group, a dimethylaminocarbonyloxyphenyl group, a butylcarbonyloxyphenyl group, and the like.

Among the substituents of R ^{1 to} R ³ , the alkyl group may be linear or branched, and may have an unsaturated bond. Further, these alkyl groups may be substituted with an alkoxy group, an aryloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an aryl group, a hydroxy group, a halogen atom, or the like. The aryl group may be further substituted with an alkyl group, an alkoxy group, a nitro group, a cyano group, a hydroxy group, or a halogen atom. As the alkyl group, an alkyl group having 1 to 30 carbon atoms is preferable, for example, methyl group, trifluoromethyl group, ethyl group, butyl group, hexyl group, octyl group, 2-ethylhexyl group, decyl group, dodecyl group, Octadecyl group, propyl group, isopropyl group, isobutyl group, sec-butyl group, t-butyl group, pentyl group,
1-ethylpentyl, cyclopentyl, cyclohexyl, isopentyl, heptyl, nonyl, undecyl, propenyl, heptadecenyl, t-octyl, ethoxycarbonylmethyl, butoxycarbonylmethyl, 2-ethylhexyloxycarbonyl Methyl group, 1- (ethoxycarbonyl) ethyl group, 2 ′,
4′-diisopentylphenyloxymethyl group, 2 ′,
4'-di-t-butylphenyloxymethyl group, ethoxycarbonylethyl group, 2-ethylhexyloxycarbonylethyl group, butyldecyloxycarbonylethyl group, dibutylaminocarbonylmethyl group, dibenzylaminocarbonylethyl group, ethyloxycarbonylpropyl Group, 2-ethylhexyloxycarbonylpropyl group, 2,4-di-t-amylphenyloxypropyl group, 1- (2 ′, 4′-di-t-amylphenyloxy) propyl group, 2,4-di- t-butylphenyloxypropyl group, acetylaminoethyl group, N, N-dihexylaminocarbonylethyl group, 2,4-di-t-amyloxyethyloxycarbonylpropyl group, isostearyloxycarbonylpropyl, 1- (2, 4-di-t-pentylphenylo ) Propyl group, 2,4
Di-t-pentylphenyloxyethyloxycarbonylpropyl group, naphthyloxyethyloxycarbonylethyl group, N-methyl-N-phenylethyloxycarbonylethyl group, methanesulfonylaminopropyl group,
And the like.

Among the substituents of R ^{1 to} R ³ , the acyl group is preferably an acyl group having 2 to 20 carbon atoms, for example, acetyl, propanoyl, butanoyl, hexanoyl, octanoyl, 2-octanoyl, Examples include an ethylhexanoyl group, a decanoyl group, a dodecanoyl group, an octadecanoyl group, a 2-cyanopropanoyl group, and a 1,1-dimethylpropanoyl group.

Among the substituents of R ^{1 to} R ³ , the alkoxycarbonyl group is preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, for example, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group,
Butoxycarbonyl group, hexyloxycarbonyl group,
2-ethylhexyloxycarbonyl group, octyloxycarbonyl group, decyloxycarbonyl group, octadecyloxycarbonyl group, phenyloxyethyloxycarbonyl group, phenyloxypropyloxycarbonyl group, 2,4-di-t-amylphenyloxyethylcarbonyl group , 2,6-di-t-butyl-4-methylcyclohexyloxycarbonyl group, isostearyloxycarbonyl group and the like.

Among the substituents of R ^{1 to} R ³ , the substituted amino group includes an amino group, an N-alkylamino group, an N-arylamino group, an N-acylamino group, an N-sulfonylamino group, an N, N- Dialkylamino group, N, N-diarylamino group, N-alkyl-N-arylamino group,
And N-disulfonylamino group. As the substituted amino group, a substituted amino group having 0 to 50 carbon atoms is preferable. For example, an N-methylamino group, an N-ethylamino group, an N-propylamino group, an N-isopropylamino group, an N-tertbutylamino group N-hexylamino group, N-cyclohexylamino group, N-octylamino group, N-2-ethylhexylamino group, N-decylamino group, N-octadecylamino group, N-benzylamino group, N-phenylamino group, N-2-methylphenylamino group, N-2-chlorophenylamino group, N-2-methoxyphenylamino group, N-2-isopropoxyphenylamino group, N-2- (2-ethylhexyloxy)
Phenylamino group, N-3-chlorophenylamino group,
N-3-nitrophenylamino group, N-3-cyanophenylamino group, N-4-methoxyamino group, N-4-
(2′-ethylhexyloxy) phenylamino group, N
-4-cyanophenylamino group, N-methyl-N-phenylamino group, N, N-dimethylamino group, N, N-dibutylamino group, N, N-diphenylamino group, N, N
-Diacetylamino group, N, N-dibenzoylamino group, N, N- (dibutylcarbonyl) amino group, N, N
A-(di-2-ethylhexylcarbonyl) amino group,
N, N- (dimethylsulfonyl) amino group, N, N-
(Diethylsulfonyl) amino group, N, N- (dibutylsulfonyl) amino group, N, N- (2-ethylhexylsulfonyl) amino group, N, N- (diphenylsulfonyl) amino group and the like.

Among the substituents of R ¹ and R ² , the substituted carbamoyl group includes a carbamoyl group, an N-alkylcarbamoyl group, an N-arylcarbamoyl group, an N, N-dialkylcarbamoyl group, and an N, N-diarylcarbamoyl group. , N-alkyl-N-arylcarbamoyl groups and the like. Examples of the substituted carbamoyl group include C1 to C1
30 substituted carbamoyl groups are preferred, for example, N-methylcarbamoyl group, N-ethylcarbamoyl group, N-
A propylcarbamoyl group, an N-butylcarbamoyl group,
N-hexylcarbamoyl group, N-cyclohexylcarbamoyl group, N-octylcarbamoyl group, N-2-ethylhexylcarbamoyl group, N-decylcarbamoyl group, N-octadecylcarbamoyl group, N-phenylcarbamoyl group, N-2-methylphenyl Carbamoyl group, N-2-chlorophenylcarbamoyl group, N-2-
Methoxyphenylcarbamoyl group, N-2-isopropoxyphenylcarbamoyl group, N-2- (2-ethylhexyloxy) phenylcarbamoyl group, N-3-chlorophenylcarbamoyl group, N-3-nitrophenylcarbamoyl group, N-3- Cyanophenylcarbamoyl group, N-4-methoxycarbamoyl group, N-4- (2 ′
-Ethylhexyloxy) phenylcarbamoyl group, N
-4-cyanophenylcarbamoyl group, N-methyl-N
-Phenylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-dibutylcarbamoyl group, N, N-diphenylcarbamoyl group and the like.

Among the substituents of R ¹ and R ² , the aryloxycarbonyl group is preferably an aryloxycarbonyl group having 7 to 30 carbon atoms, for example, 2-methylphenyloxycarbonyl group, 2-chlorophenyloxycarbonyl Group, 2,6-dimethylphenyloxycarbonyl group, 2,4,6-trimethylphenyloxycarbonyl group, 2-methoxyphenyloxycarbonyl group,
2-butoxyphenyloxycarbonyl group, 3-cyanophenyloxycarbonyl group, 3-nitrophenyloxycarbonyl group, 2,2-ethylhexylphenyloxycarbonyl group, 3- (2-ethylhexyloxy) phenyloxycarbonyl group, 4-fluoro Examples thereof include a phenyloxycarbonyl group, a 4-chlorophenyloxycarbonyl group, a 4-cyanophenyloxycarbonyl group, and a 4-butoxyphenyloxycarbonyl group.

Among the substituents for R ¹ and R ² , the alkylsulfonyl group is preferably an alkylsulfonyl group having 1 to 20 carbon atoms, for example, a methylsulfonyl group, an ethylsulfonyl group, a propylsulfonyl group, an isopropylsulfonyl group, Butylsulfonyl, hexylsulfonyl, cyclohexylsulfonyl, octylsulfonyl, 2-ethylhexylsulfonyl, decanoylsulfonyl, dodecanoylsulfonyl, octadecanoylsulfonyl, cyanomethylsulfonyl and the like.

Among the substituents for R ¹ and R ² , the arylsulfonyl group is preferably an arylsulfonyl group having 6 to 30 carbon atoms, for example, a phenylsulfonyl group,
1-naphthylsulfonyl group, 2-naphthylsulfonyl group, 2-chlorophenylsulfonyl group, 2-methylphenylsulfonyl group, 2-methoxyphenylsulfonyl group, 2-butoxyphenylsulfonyl group, 3-chlorophenylsulfonyl group, 3-trifluoromethyl Phenylsulfonyl group, 3-cyanophenylsulfonyl group, 3-
A (2-ethylhexyloxy) phenylsulfonyl group,
3-nitrophenylsulfonyl group, 4-fluorophenylsulfonyl group, 4-cyanophenylsulfonyl group, 4
-Butoxyphenylsulfonyl group, 4- (2-ethylhexyloxy) phenylsulfonyl group, 4-octadecylphenylsulfonyl group and the like.

Among the substituents of R ¹ and R ² , the substituted sulfamoyl group includes sulfamoyl, N-alkylsulfamoyl, N-arylsulfamoyl, N, N-
It includes a dialkylsulfamoyl group, an N, N-diarylsulfamoyl group, and an N-alkyl-N-arylsulfamoyl group.

Of the substituents for R ¹ and R ² , the substituted sulfamoyl group is preferably a substituted sulfamoyl group having 0 to 30 carbon atoms, for example, an N-methylsulfamoyl group or an N-ethylsulfamoyl group , N-propylsulfamoyl group, N-butylsulfamoyl group, N-hexylsulfamoyl group, N-cyclohexylsulfamoyl group, N-octylsulfamoyl group, N-2-ethylhexylsulfamoyl group N-decylsulfamoyl group, N-octadecylsulfamoyl group, N-phenylsulfamoyl group, N-2-methylphenylsulfamoyl group, N-2-chlorophenylsulfamoyl group,
N-2-methoxyphenylsulfamoyl group, N-2-
Isopropoxyphenylsulfamoyl group, N-2-
(2-ethylhexyloxy) phenylsulfamoyl group, N-3-chlorophenylsulfamoyl group, N-3
-Nitrophenylsulfamoyl group, N-3-cyanophenylsulfamoyl group, N-4-methoxysulfamoyl group, N-4- (2'-ethylhexyloxy) phenylsulfamoyl group, N-4- Cyanophenylsulfamoyl group, N-methyl-N-phenylsulfamoyl group, N, N-dimethylsulfamoyl group, N, N-dibutylsulfamoyl group, N, N-diphenylsulfamoyl group, N , N-di (2-ethylhexyl) sulfamoyl group and the like.

Among the substituents for R ³ , examples of the halogen atom include a fluorine atom, a chlorine atom and a bromine atom, and a fluorine atom and a chlorine atom are more preferred.

Among the substituents for R ³ , the alkoxy group is preferably an alkoxy group having 1 to 30 carbon atoms, for example, methoxy, ethoxy, propyloxy, isopropyloxy, butoxy, isobutoxy, s
ec-butoxy, t-butoxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy, decyloxy, dodecyloxy, octadecyloxy, ethoxycarbonyl Methyloxy group, 2
-Ethylhexyloxycarbonylmethyloxy group, aminocarbonylmethyloxy group, N, N-dibutylaminocarbonylmethyloxy group, N-methylaminocarbonylmethyloxy group, N-ethylaminocarbonylmethyloxy group, N-octylaminocarbonylmethyloxy Group, N-methyl-N-benzylaminocarbonylmethyloxy group, benzyloxy group, cyanomethyloxy group and the like.

Among the substituents of R ^3, the aryloxy group is preferably an aryloxy group having 6 to 30 carbon atoms, such as phenyloxy, 1-naphthyloxy, 2-naphthyloxy, -Chlorophenyloxy group, 2-methylphenyloxy group, 2-methoxyphenyloxy group, 2-butoxyphenyloxy group, 3-chlorophenyloxy group, 3-trifluoromethylphenyloxy group, 3-cyanophenyloxy group, 3 -(2-ethylhexyloxy) phenyloxy group, 3-nitrophenyloxy group, 4-fluorophenyloxy group, 4-
Examples include a cyanophenyloxy group, a 4-butoxyphenyloxy group, a 4- (2-ethylhexyloxy) phenyloxy group, and a 4-octadecylphenyloxy group.

Among the substituents for R ³ , the alkylthio group is preferably an alkylthio group having 1 to 30 carbon atoms, such as methylthio, ethylthio, propylthio, isopropylthio, butylthio, isobutylthio, sec-butylthio group, t-butylthio group, pentylthio group, isopentylthio group, hexylthio group,
Heptylthio group, octylthio group, 2-ethylhexylthio group, decylthio group, dodecylthio group, octadecylthio group, ethoxycarbonylmethylthio group, 2-ethylhexyloxycarbonylmethylthio group, aminocarbonylmethylthio group, N, N-dibutylaminocarbonylmethyl group, An N-methylaminocarbonylmethylthio group,
Examples thereof include an N-ethylaminocarbonylmethylthio group, an N-octylaminocarbonylmethylthio group, an N-methyl-N-benzylaminocarbonylmethylthio group, a benzylthio group, and a cyanomethylthio group.

Among the substituents for R ³ , the arylthio group is preferably an arylthio group having 6 to 30 carbon atoms, such as phenylthio, 1-naphthylthio,
-Naphthylthio, 2-chlorophenylthio, 2-methylphenylthio, 2-methoxyphenylthio, 2
-Butoxyphenylthio, 3-chlorophenylthio, 3-trifluoromethylphenylthio, 3-cyanophenylthio, 3- (2-ethylhexyloxy)
Phenylthio, 3-nitrophenylthio, 4-fluorophenylthio, 4-cyanophenylthio, 4-
Butoxyphenylthio, 4- (2-ethylhexyloxy) phenylthio, 4-octadecylphenylthio, and the like.

Hereinafter, typical specific examples of the pyrrolotriazinone compound represented by the general formula (1), which is the coupler of the present invention, will be described, but the present invention is not limited thereto. Hereinafter, the substituents used in the compound examples are described in numerical order, and combinations thereof are shown in Table 1. R ^{1 to} R ³ in the table
Numerical values in the column indicate a substituent number.

[0040]

Embedded image

[0041]

Embedded image

[0042]

Embedded image

[0043]

Embedded image

[0044]

Embedded image

[0045]

Embedded image

[0046]

[Table 1]

These pyrrolotriazineone compounds represented by the general formula (1) may be used alone or in combination of two or more.

The coupler according to the present invention forms a dye by coupling with a diazo compound in a basic atmosphere and / or a neutral atmosphere. The coupler according to the present invention can be used in combination with a known coupler according to various purposes such as hue adjustment. Examples of the coupler to be used in combination include a so-called active methylene compound having a methylene group next to a carbonyl group, a phenol derivative, and a naphthol derivative. .

Particularly preferred couplers that can be used in the present invention are resorcin, phloroglucin, 2,3-dihydroxynaphthalene, sodium 2,3-dihydroxynaphthalene-6-sulfonate, and morpholinopropyl 1-hydroxy-2-naphthoate. Amide,
Sodium 2-hydroxy-3-naphthalenesulfonate, 2-hydroxy-3-naphthalenesulfonic acid anilide, 2-hydroxy-3-naphthalenesulfonic acid morpholinopropylamide, 2-hydroxy-3-naphthalenesulfonic acid-2-ethylhexyloxypropyl Amide, 2-hydroxy-3-naphthalenesulfonic acid-2-
Ethylhexylamide, 5-acetamido-1-naphthol, 1-hydroxy-8-acetamidonaphthalene-
Sodium 3,6-disulfonate, 1-hydroxy-8
-Acetamidonaphthalene-3,6-disulfonic acid dianilide, 1,5-dihydroxynaphthalene, 2-hydroxy-3-naphthoic acid morpholinopropylamide, 2-
Hydroxy-3-naphthoic acid octylamide, 2-hydroxy-3-naphthoic acid anilide, 5,5-dimethyl-
1,3-cyclohexanedione, 1,3-cyclopentanedione, 5- (2-n-tetradecyloxyphenyl) -1,3-cyclohexanedione, 5-phenyl-
4-methoxycarbonyl-1,3-cyclohexanedione, 5- (2,5-di-n-octyloxyphenyl)
-1,3-cyclohexanedione, N, N'-dicyclohexylbarbituric acid, N, N'-di-n-dodecylbarbituric acid, Nn-octyl-N'-n-octadecyl barbituric acid, N- Phenyl-N '-(2,5
-Di-n-octyloxyphenyl) barbituric acid,
N, N'-bis (octadecyloxycarbonylmethyl) barbituric acid, 1-phenyl-3-methyl-5-
Pyrazolone, 1- (2,4,6-trichlorophenyl)
-3-anilino-5-pyrazolone, 1- (2,4,6-
Trichlorophenyl) -3-benzamido-5-pyrazolone, 6-hydroxy-4-methyl-3-cyano-1-
(2-ethylhexyl) -2-pyridone, 2,4-bis- (benzoylacetamido) toluene, 1,3-bis- (pivaloylacetoamidomethyl) benzene, benzoylacetonitrile, thenoylacetonitrile, acetoacetanilide, benzoylacetanilide, Pivaloylacetoanilide, 2-chloro-5- (Nn-butylsulfamoyl) -1-pivaloylacetamidobenzene, 1- (2-ethylhexyloxypropyl) -3-
Cyano-4-methyl-6-hydroxy-1,2-dihydropyridin-2-one, 1- (dodecyloxypropyl) -3-acetyl-4-methyl-6-hydroxy-
1,2-dihydropyridin-2-one, 1- (4-n-
Octyloxyphenyl) -3-tert-butyl-5
-Aminopyrazole and the like.

For details of the coupler, see JP-A-4-4-2.
01483, JP-A-7-223267, JP-A-7-223
223368, JP-A-7-323660, Japanese Patent Application No. 5
-278608, Japanese Patent Application No. 5-297024, Japanese Patent Application No. 6-18669, Japanese Patent Application No. 6-18670, Japanese Patent Application No. 7
-316280, Japanese Patent Application No.8-027095, Japanese Patent Application No.8-027096, Japanese Patent Application No.8-030799, Japanese Patent Application No.8-12610, Japanese Patent Application No.8-132394, Japanese Patent Application No.8-358755. And Japanese Patent Application Nos. 8-358756 and 9-069990.

The amount of the coupler to be added is 0.1 to 0.1 in the heat-sensitive recording layer.
It is used in the range of 02 to 5 g / m ² , and preferably 0.1 to 4 g / m ^{2 in} terms of effect. If the addition amount is less than 0.02 g / m ^2, it is not preferable from the viewpoint of color development, and if it exceeds 5 g / m ² , it is not preferable from the viewpoint of application suitability.

The diazonium salt compound used in the present invention is a compound represented by the following general formula: Ar—N ₂ ⁺ X ⁻ [wherein Ar represents an aromatic moiety and X ⁻ represents an acid anion] A compound that develops a color by causing a coupling reaction with a coupler when heated and decomposes by light. These can control the maximum absorption wavelength depending on the position and type of the substituent in the Ar portion.

Specific examples of the salt-forming diazonium include 4- (p-tolylthio) -2,5-dibutoxybenzenediazonium and 4- (4-chlorophenylthio)-
2,5-dibutoxybenzenediazonium, 4- (N,
N-dimethylamino) benzenediazonium, 4-
(N, N-diethylamino) benzenediazonium, 4
-(N, N-dipropylamino) benzenediazonium, 4- (N-methyl-N-benzylamino) benzenediazonium, 4- (N, N-dibenzylamino) benzenediazonium, 4- (N-ethyl-N -Hydroxyethylamino) benzenediazonium, 4- (N, N-
Diethylamino) -3-methoxybenzenediazonium, 4- (N, N-dimethylamino) -2-methoxybenzenediazonium, 4- (N-benzoylamino)-
2,5-diethoxybenzenediazonium, 4-morpholino-2,5-dibutoxybenzenediazonium, 4-
Anilinobenzenediazonium, 4- [N- (4-methoxybenzoyl) amino] -2.5-diethoxybenzenediazonium, 4-pyrrolidino-3-ethylbenzenediazonium, 4- [N- (1-methyl-2- ( 4-methoxyphenoxy) ethyl) -N-hexylamino]-
2-hexyloxybenzenediazonium, 4- [N-
(2- (4-methoxyphenoxy) ethyl) -N-hexylamino] -2-hexyloxybenzenediazonium, 2- (1-ethylpropyloxy) -4- [di-
(Di-n-butylaminocarbonylmethyl) amino] benzenediazonium and the like.

The maximum absorption wavelength λmax of the diazonium salt compound used in the present invention is preferably 450 nm or less from the viewpoint of the effect, and more preferably 290 to 440 nm. When the diazonium salt compound has λmax on the longer wavelength side than the above wavelength region, in terms of raw preservability, image fixing property, image preservability, and purple to cyan coloring in combination with a coupler having λmax on the shorter wavelength side have a λmax on the shorter wavelength side. Neither is preferred in terms of hue. Further, the diazonium salt compound used in the present invention preferably has 12 or more carbon atoms, a solubility in water of 1% or less, and a solubility in ethyl acetate of 5% or more.

Among these diazonium salt compounds,
It is more preferable to use the diazonium salt compound represented by the general formula (2), the general formula (3), or the general formula (4) in terms of the hue of the dye, image storability, and image fixability.

In the general formula (2), Ar represents a substituted or unsubstituted aryl group. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group, an acyl group, an alkoxycarbonyl group, a carbamoyl group, a carboxamide group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, Examples thereof include a halogen group, an amino group and a heterocyclic group, and these substituents may be further substituted.

The aryl group is preferably a compound having 6 to 6 carbon atoms.
30 aryl groups are preferred, for example a phenyl group, 2
-Methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2-
An ethylhexyloxy) phenyl group, a 2-octyloxyphenyl group, a 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, a 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2 -Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like, but are not particularly limited thereto.
Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, or the like.

R ¹¹ and R ¹² each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹¹ and R ¹² may be the same or different. Examples of the substituent include, but are not limited to, an alkoxy group, an alkoxycarbonyl group, an alkylsulfonyl group, a substituted amino group, a substituted amide group, an aryl group, an aryloxy group, and the like.

The alkyl group may have 1 to 18 carbon atoms.
Are preferred, for example, a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group,
Butyl group, sec-butyl group, t-butyl group, pentyl group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl group, nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group, tolphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, 2 ′, 4′-diisopentyl Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- ( 2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
A diethylamino) propyl group is preferred.

The aryl group has 6 carbon atoms.
~ 30 aryl groups are preferable, for example, a phenyl group,
2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2
-Ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2 -Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like, but are not particularly limited thereto. Further, these groups further include an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group,
It may be substituted by a halogen atom, a heterocyclic group or the like.

In the general formula (3), R ¹⁴ , R ¹⁵ , R ¹⁶
Represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, respectively. R ¹⁴ , R ¹⁵ , R ¹⁶
May be the same or different. As the substituent, an alkyl group, an alkoxy group, an alkylthio group,
Aryl group, aryloxy group, arylthio group, acyl group, alkoxycarbonyl group, carbamoyl group, carboamide group, sulfonyl group, sulfamoyl group, sulfonamide group, ureido group, halogen atom, amino group, heterocyclic group, etc. .

The alkyl group may have 1 to 18 carbon atoms.
Are preferred, for example, a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group,
Butyl group, sec-butyl group, t-butyl group, ventil group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl, nonyl, octadecyl, benzyl, 4-methoxybenzyl, triphenylmethyl, ethoxycarbonylmethyl, butoxycarbonylmethyl, 2-ethylhexyloxycarbonylmethyl, 2 ', 4'-diisopentyl Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- ( 2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
Diethylamino) propyl group, 1-methyl-2- (4-
(Methoxyphenoxy) ethyl group, di-n-butylaminocarbonylmethyl group, di-n-octylaminocarbonylmethyl group and the like are preferable.

The aryl group has 6 carbon atoms.
~ 30 aryl groups are preferable, for example, a phenyl group,
2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2
-Ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2 -Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like, but are not particularly limited thereto.
Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, or the like.

Y represents a hydrogen atom or an —OR ¹³ group.
In the R ¹³ group, R ¹³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group, an aryloxy group, an arylthio group,
Acyl group, alkoxycarbonyl group, carbamoyl group,
Examples thereof include a carboamide group, a sulfonyl group, a sulfamoyl group, a sulfonamide group, a ureido group, a halogen atom, an amino group, and a heterocyclic group. In terms of hue adjustment, Y
Is preferably a hydrogen atom or an alkyloxy group wherein R ¹³ is an alkyl group.

The alkyl group may have 1 to 18 carbon atoms.
Are preferred, for example, a methyl group, a trifluoromethyl group, an ethyl group, a propyl group, an isopropyl group,
Butyl group, sec-butyl group, t-butyl group, ventil group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl group, nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group, tolphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, 2 ′, 4′-diisopentyl Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- ( 2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
A diethylamino) propyl group is preferred.

The aryl group has 6 carbon atoms.
~ 30 aryl groups are preferable, for example, a phenyl group,
2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2
-Ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- (2 -Ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like, but are not particularly limited thereto.
Further, these groups may be further substituted by an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group, a substituted amino group, a halogen atom, a heterocyclic group, or the like.

In the general formula (4), R ¹⁷ and R ¹⁸ each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹⁷ and R ¹⁸ may be the same or different. As the substituent, an alkyl group, an alkoxy group, an alkylthio group, an aryl group,
Aryloxy group, arylthio group, acyl group, alkoxycarbonyl group, carbamoyl group, carboamide group,
Sulfonyl group, sulfamoyl group, sulfonamide group,
Examples include a ureido group, a halogen atom, an amino group, and a heterocyclic group.

The alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, such as methyl, trifluoromethyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, and the like. Pentyl group, isopentyl group, cyclopentyl group, hexyl group,
Cyclohexyl group, octyl group, t-octyl group, 2-
Ethylhexyl group, nonyl group, octadecyl group, benzyl group, 4-methoxybenzyl group, triphenylmethyl group, ethoxycarbonylmethyl group, butoxycarbonylmethyl group, 2-ethylhexyloxycarbonylmethyl group, 2 ′, 4′-diisobenzene Phenyloxymethyl group, 2 ′, 4′-di-t-butylphenyloxymethyl group, dibenzylaminocarbonylmethyl group, 2,4-di-t-amylphenyloxypropyl group, ethoxycarbonylpropyl group, 1- (2 ′, 4′-di-t-amylphenyloxy) propyl group, acetylaminoethyl group, 2- (N, N-dimethylamino) ethyl group, 2-
(N, N-diethylamino) propyl group, methanesulfonylaminopropyl group, acetylaminoethyl group, 2-
(N, N-dimethylamino) ethyl group, 2- (N, N-
A diethylamino) propyl group and the like are preferable, but not particularly limited thereto.

The aryl group has 6 carbon atoms.
~ 30 aryl groups are preferable, for example, a phenyl group,
2-methylphenyl group, 2-chlorophenyl group, 2-methoxyphenyl group, 2-butoxyphenyl group, 2- (2
-Ethylhexyloxy) phenyl group, 2-octyloxyphenyl group, 3- (2,4-di-t-pentylphenoxyethoxy) phenyl group, 4-chlorophenyl group,
2,5-dichlorophenyl group, 2,4,6-trimethylphenyl group, 3-chlorophenyl group, 3-methylphenyl group, 3-methoxyphenyl group, 3-butoxyphenyl group, 3-cyanophenyl group, 3- ( 2-ethylhexyloxy) phenyl group, 3,4-dichlorophenyl group,
3,5-dichlorophenyl group, 3,4-dimethoxyphenyl group, 3- (dibutylaminocarbonylmethoxy) phenyl group, 4-cyanophenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-butoxyphenyl group, 4- (2-ethylhexyloxy) phenyl group, 4
-Benzylphenyl group, 4-aminosulfonylphenyl group, 4-N, N-dibutylaminosulfonylphenyl group, 4-ethoxycarbonylphenyl group, 4- (2-ethylhexylcarbonyl) phenyl group, 4-fluorophenyl group, 3- Acetylphenyl group, 2-acetylaminophenyl group, 4- (4-chlorophenylthio) phenyl group, 4- (4-methylphenyl) thio-2,5-butoxyphenyl group, 4- (N-benzyl-N-methyl Amino) -2-dodecyloxycarbonylphenyl group, and the like. Further, these groups further include an alkyloxy group, an alkylthio group, a substituted phenyl group, a cyano group,
It may be substituted by a substituted amino group, a halogen atom, a heterocyclic group or the like.

In the general formulas (2), (3) and (4), X ⁻ represents an acid anion, wherein the acid anion is a polyfluoroalkylcarboxylic acid having 1 to 9 carbon atoms, a carbon atom Examples include polyfluoralkylsulfonic acids of the formulas 1 to 9, boron tetrafluoride, tetraphenylboron, hexafluorophosphoric acid, aromatic carboxylic acids, and aromatic sulfonic acids. Hexafluorophosphoric acid is preferred from the viewpoint of crystallinity.

Hereinafter, specific examples of the diazonium salt compound represented by the general formula (2), (3) or (4) are shown, but the present invention is not limited thereto.

[0072]

Embedded image

[0073]

Embedded image

[0074]

Embedded image

[0075]

Embedded image

In the present invention, the diazonium salt compounds represented by the general formula (2), (3) or (4) may be used alone or in combination of two or more. . Further, the diazonium salt compound represented by the general formula (2), (3) or (4) may be used in combination with an existing diazonium salt compound according to various purposes such as hue adjustment.

The diazonium salt compound used in the present invention is preferably contained in the heat-sensitive recording layer in an amount of 0.02 to 3 g / m ² , more preferably 0.1 to ² g / m ² .

The diazonium salt compound used in the present invention is preferably encapsulated in microcapsules from the viewpoint of storage stability. The method of microencapsulation is not particularly limited, and microencapsulation can be performed by a conventionally known method using a wall material such as gelatin, polyurea, polyurethane, polyimide, polyester, polycarbonate, and melamine. Details of the microencapsulation method are described in JP-A-2-141279 and the like. In microencapsulation, a high-boiling organic solvent may be used as a dispersion solvent for the diazonium salt compound. The organic solvent is not particularly limited, and conventionally known ones such as an alkyl phthalate, a phosphate, a citrate, a benzoate, an alkylamide, an aliphatic ester, and a trimesate can be used. . Details are described in JP-A-7-17145.

In the present invention, an organic base such as a tertiary amine, piperidine, piperazine, amidine, formamidine, pyridine, guanidine or morpholine is used for the purpose of promoting the coupling reaction. Is preferred.

Specific examples of these organic bases include N,
N′-bis (3-phenoxy-2-hydroxypropyl) piperazine, N, N′-bis [3- (p-methylphenoxy) -2-hydroxypropyl] piperazine,
N, N'-bis [3- (p-methoxyphenoxy) -2
-Hydroxypropyl] piperazine, N, N'-bis (3-phenylthio-2-hydroxypropyl) piperazine, N, N'-bis [3- (β-naphthoxy) -2-
Hydroxypropyl] piperazine, N-3- (β-naphthoxy) -2-hydroxypropyl-N′-methylpiperazine, 1,4-bis {[3- (N-methylpiperazino) -2-hydroxy] propyloxy} benzene Piperazines, N- [3- (β-naphthoxy) -2-
Hydroxy] propylmorpholine, 1,4-bis [(3
Morpholinos such as -morpholino-2-hydroxy) propyloxy] benzene, 1,3-bis [(3-morpholino-2-hydroxy) propyloxy] benzene, N
-Piperidines such as-(3-phenoxy-2-hydroxypropyl) piperidine, N-dodecylpiperidine, triphenylguanidine, tricyclohexylguanidine, dicyclohexylphenylguanidine, 2-N-methyl-N-benzylaminoethyl 4-hydroxybenzoate Ester, 4-hydroxybenzoic acid 2-N, N-di-
n-butylaminoethyl ester, 4- (3-N, N-
Dibutylaminopropoxy) benzenesulfonamide,
4- (2-N, N-dibutylaminoethoxycarbonyl) phenoxyacetic acid amide and the like. Details of these are described in JP-A-57-123086, JP-A-60-49991, JP-A-60-94381, Japanese Patent Application No. 7-228731, and Japanese Patent Application No. 7-2351.
No. 57 and Japanese Patent Application No. 7-235158. These organic bases can be used alone or in combination of two or more. The amount of the organic base used in the present invention is not particularly limited, but is preferably in the range of 1 to 30 mol per 1 mol of the diazonium salt compound.

The coupler of the present invention can be used by adding a water-soluble polymer together with other components and solid-dispersing it by a sand mill or the like, but can also be used as an emulsion together with a suitable emulsifying aid. The solid dispersion method and the emulsification method are not particularly limited, and conventionally known methods can be used. Details of these methods are described in JP-A-59-190886, JP-A-2-141279, and JP-A-7-17145.

In the present invention, in addition to the pyrrolotriazinone compound represented by the general formula (1), a coloring aid may be added for the purpose of accelerating the coloring reaction. Examples of these color development aids include phenol derivatives, naphthol derivatives, alkoxy-substituted benzenes, alkoxy-substituted naphthalenes, hydroxy compounds, carboxylic acid amide compounds, and sulfonamide compounds. It is considered that these compounds reduce the melting point of the coupler or the basic substance or improve the heat permeability of the microcapsule wall, and as a result, a high color density can be obtained.

The heat-sensitive recording material of the present invention is prepared by preparing a coating solution containing a diazonium salt compound, a pyrrolotriazinone compound represented by the general formula (1), and other additives, and supporting a paper or a synthetic resin film. Bar application on the body,
Coating and drying with a coating method such as blade coating, air knife coating, gravure coating, roll coating coating, spray coating, dip coating, curtain coating, etc.
g / m ² of the thermosensitive recording layer.

The binder used in the present invention is not particularly limited, and a conventionally known binder such as polyvinyl alcohol, hydroxyethyl cellulose, methyl cellulose, carboxymethyl cellulose, gelatin, styrene-acrylic acid copolymer and the like may be used. Can be. For details, see JP-A-2-1412.
No. 79, and the like. In addition, various organic or inorganic pigments, various stabilizers, antioxidants, and the like can be added as necessary.

In the heat-sensitive recording material of the present invention, the diazonium salt compound, the pyrrolotriazine-one compound represented by the general formula (1) may be contained in the same layer as described in the above method, or may be contained in another layer. Can be taken as a laminated type.

As the support used in the present invention, a conventionally known support can be used. Specifically, neutral paper, acidic paper, recycled paper, polyolefin resin laminated paper, synthetic paper, polyester film, cellulose derivative film such as cellulose triacetate film, polystyrene film, polyolefin film such as polypropylene film and polyethylene film, etc. These can be used alone or bonded together. The thickness of the support is 20 to 200 μm. It is also possible to provide an intermediate layer between the support and the thermosensitive recording layer. This is described in JP-A-61-5498.
No. 0 publication.

In the heat-sensitive recording material of the present invention, it is preferable to provide a protective layer on the heat-sensitive recording layer, and it is more preferable to provide the protective layer in a laminated manner. This protective layer is composed of a water-soluble polymer compound, a pigment and the like. It is preferable that a compound having an ultraviolet transmittance adjusting function is contained in the protective layer from the viewpoint of achieving both light resistance and light fixing property.
The thermosensitive recording material containing the compound having the function of adjusting the ultraviolet transmittance is described in detail in JP-A-7-276808.

The heat-sensitive recording material of the present invention can be used for multicolor heat-sensitive recording materials. The multicolor heat-sensitive recording material (heat-sensitive recording material) is disclosed in Japanese Patent Application Laid-Open No. 4-135787.
JP-A-4,144,784 and JP-A-4-144478
No. 5, No. 4-194842, No. 4-2474
Nos. 47, 4-247448, 4-340
Nos. 540, 4-340541 and 5-34
860 and the like. Specifically, it can be obtained by laminating thermosensitive recording layers that develop colors of different hues. The layer configuration is not particularly limited, but as an example, a thermosensitive recording in which two kinds of diazonium salt compounds having different photosensitive wavelengths are reacted with the respective diazonium salt compounds when heated to form a coupler which develops a different hue is used. Thermal recording layer (layer A) combining two layers (layers B and C), a colorless electron-donating dye and an electron-accepting compound
And a multi-color heat-sensitive recording material obtained by laminating the above. Specifically, a first thermosensitive recording layer (layer A) containing a colorless electron-donating dye and an electron-accepting compound on a support, a maximum absorption wavelength of 360
a second heat-sensitive recording layer (B layer) containing a diazonium salt compound having a wavelength of ± 20 nm and a coupler which reacts with the diazonium salt compound when heated to give a color, and has a maximum absorption wavelength of 400 ±.
A third heat-sensitive recording layer (C layer) containing a diazonium salt compound having a thickness of 20 nm and a coupler which reacts with the diazonium salt compound when heated to give a color. In this example, if the color hues of the respective heat-sensitive recording layers are selected so as to be three primary colors in the subtractive color mixing, yellow, magenta, and cyan, a full-color image can be recorded.

In the recording method of this multicolor heat-sensitive recording material, first, the third heat-sensitive recording layer (C layer) is heated so that the diazonium salt and the coupler contained in the layer are colored. Then 400 ±
After irradiating 20 nm light to decompose the unreacted diazonium salt compound contained in the C layer and fix it by light, sufficient heat is applied to the second thermosensitive recording layer (B layer) to develop color,
The diazonium salt compound and the coupler contained in the layer are colored. At this time, the C layer is also heated strongly, but the diazonium salt compound has already been decomposed (fixed by light) and the color forming ability has been lost, so that no color is formed. Further, the diazonium salt compound contained in the B layer is decomposed by irradiating light of 360 ± 20 nm, and finally the first
The heat-sensitive recording layer (layer A) is colored by applying sufficient heat to develop color. At this time, the heat-sensitive recording layers C and B are also strongly heated at the same time, but the diazonium salt compound has already been decomposed and the color-forming ability is lost, so that no color is formed.

Further, all the heat-sensitive recording layers (A layer, B layer, and C layer in order from the upper layer) were heated and reacted with three kinds of diazonium salt compounds having different photosensitive wavelengths. It can also be composed of a heat-sensitive recording layer in which a coupler that develops a hue is combined. In particular,
Such a layer configuration is required when the yellow layer having low visibility is used as the lowermost layer to improve the image quality by reducing the influence on the image quality due to the roughness on the surface of the support. When all the heat-sensitive recording layers (A layer, B layer, and C layer) are diazo-based heat-sensitive recording layers, it is necessary to fix the layers A and B after color development. For the layer C, it is not necessary to perform light fixing.

Various fluorescent lamps, xenon lamps, mercury lamps and the like are used as a fixing light source used for the above-mentioned light fixing. It is preferable that this emission spectrum substantially coincides with the absorption spectrum of the diazonium salt compound used in the heat-sensitive recording material, because the light can be efficiently fixed.

In recording on the heat-sensitive recording material of the present invention, the material is exposed through an original to decompose a diazonium salt compound other than at the image forming portion to form a latent image, and then heat and heat the entire material. It can also be used as a heat-developable photosensitive material for obtaining an image.

[0093]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.
In addition, "part" in an Example shows all weight parts. [Example 1] [Preparation of microcapsule liquid A] To 19 parts of ethyl acetate, 2.8 parts of a diazonium salt (exemplified compound (3) -1) and 10 parts of tricresyl phosphate were added and uniformly mixed. Next, Takenate D-11 was added to this mixture as a wall material.
7.6 parts of 0N (manufactured by Takeda Pharmaceutical Co., Ltd.) was added and uniformly mixed to obtain a liquid I. Next, 46 parts of an 8% by weight aqueous solution of phthalated gelatin, 17.5 parts of water, and 2 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate were added to the solution I, and 40 parts of the solution were added.
° C, 10,000 r. p. m. For 10 minutes.
After adding 20 parts of water to the obtained emulsion and homogenizing, a microcapsulation reaction was performed at 40 ° C. for 3 hours with stirring to obtain a microcapsule liquid A. The average particle size of the microcapsules was 0.7-0.8 μm.

[Preparation of coupler emulsion B] Ethyl acetate 1
0.5 part of coupler (exemplified compound (6)) 3.0 parts, triphenylguanidine 3.0 parts, tricresyl phosphate 0.5 part, maleic acid diethyl ester 0.24
A part II solution was obtained. Next, one of lime-processed gelatin
49 parts of a 5% by weight aqueous solution, 9.5 parts of a 10% aqueous solution of sodium dodecylbenzenesulfonate and 35 parts of water were uniformly mixed at 40 ° C., and the II solution was added thereto.
° C, 10,000 r. p. m. For 10 minutes.
After stirring the obtained emulsion at 40 ° C. for 2 hours to remove ethyl acetate, the weights of the volatilized ethyl acetate and water were supplemented with water to obtain a coupler emulsion B.

[Preparation of Coating Solution C for Thermosensitive Recording Layer] 3.6 parts of microcapsule solution A, 3.3 parts of water, coupler emulsion B
9.5 parts were uniformly mixed to obtain a heat-sensitive recording layer coating solution C. [Preparation of protective layer coating solution D] Itaconic acid-modified polyvinyl alcohol (KL-318; trade name, manufactured by Kuraray Co., Ltd.)
100 parts of 6% aqueous solution and epoxy-modified polyamide (FL-
71; trade name, manufactured by Toho Chemical Co., Ltd.) 30% dispersion 1
0 part, and a dispersion of 40% zinc stearate (Hydrin Z; trade name, manufactured by Chukyo Yushi Co., Ltd.) 15
Were uniformly mixed to obtain a protective layer coating solution D.

[Coating] On a photographic paper support obtained by laminating polyethylene on a high-quality paper, a thermosensitive recording layer coating solution C and a protective layer coating solution D were sequentially coated and dried at 50 ° C. in order with a wire bar. The desired heat-sensitive recording material was obtained. The application amounts as solids were 8.0 g / m ² and 1.2 g / m ² , respectively.

[Coloring Test] After applying a thermal head (KST type) manufactured by Kyocera Corporation, determining the applied power and pulse width to the thermal head so that the recording energy per unit area is 50 mJ / mm ^2, and performing thermal printing, The whole surface was irradiated for 15 seconds using an ultraviolet lamp having an emission center wavelength of 365 nm and an output of 40 W. The density of the image portion and the background portion of the obtained sample was measured with a Macbeth densitometer.

[Test of Image Lightfastness] The image portion colored by using a thermal head (KST type) manufactured by Kyocera Corporation was examined for 24 hours at 30,000 lux using a fluorescent lamp lightfastness tester.
After continuous light irradiation, the density of the image area was measured. The higher the density of the image area after light irradiation, the better the image light resistance. [Test of Image Fixing Property] In the test of the image fixing property, the background portion (unprinted portion) of the fixed sample was subjected to recording energy per unit area of 40 mJ / mm using a thermal head (KST type) manufactured by Kyocera Corporation. ^The applied power and pulse width to the thermal head were determined so as to be ^2, and thermal printing was performed, and the density change was examined. The lower the density after printing, the better the image fixability.

[Example 2] Coupler used in Example 1
A thermosensitive recording material was prepared in the same manner as in Example 1, except that an emulsion was obtained using the coupler (7) instead of (6).
evaluated.

Example 3 Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (10) instead of (6).

Example 4 Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (11) instead of (6).

Example 5 Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (12) instead of (6).

[Embodiment 6] Coupler used in Embodiment 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (13) instead of (6).

[Embodiment 7] Coupler used in Embodiment 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (14) instead of (6).

[Embodiment 8] Coupler used in Embodiment 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (20) instead of (6).

[Example 9] Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (21) instead of (6).

Example 10 Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (25) instead of (6).

[Example 11] Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that an emulsion was obtained using the coupler (27) instead of (6).

[Example 12] Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (36) instead of (6).

Example 13 Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (43) instead of (6).

[Example 14] Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that an emulsion was obtained using the coupler (47) instead of (6).

[Embodiment 15] Coupler used in Embodiment 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (50) instead of (6).

[Example 16] Coupler used in Example 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (52) instead of (6).

[Embodiment 17] Coupler used in Embodiment 1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1, except that an emulsion was obtained using the coupler (56) instead of (6).

Example 18 A microcapsule solution was prepared using Exemplified Compound (3) -2 instead of the diazonium salt (Exemplified Compound (3) -1) used in Example 1. In the same manner as in Example 1, a thermosensitive recording material was prepared and evaluated.

Example 19 A microcapsule solution was prepared using Exemplified Compound (3) -3 in place of the diazonium salt (Exemplified Compound (3) -1) used in Example 1. In the same manner as in Example 1, a thermosensitive recording material was prepared and evaluated.

Example 20 A microcapsule solution was prepared using Exemplified Compound (3) -5 in place of the diazonium salt (Exemplified Compound (3) -1) used in Example 1. In the same manner as in Example 1, a thermosensitive recording material was prepared and evaluated.

Example 21 A microcapsule solution was prepared using Exemplified Compound (3) -8 in place of the diazonium salt (Exemplified Compound (3) -1) used in Example 1. In the same manner as in Example 1, a thermosensitive recording material was prepared and evaluated. At that time, the lamp used in the color development test was changed to one having an emission center wavelength of 420 nm.

Example 22 A microcapsule solution was prepared using Exemplified Compound (2) -1 in place of the diazonium salt (Exemplified Compound (3) -1) used in Example 1. In the same manner as in Example 1, a thermosensitive recording material was prepared and evaluated. The color development test was performed using the same lamp as in Example 21.

[Comparative Example] Instead of the coupler (6) used in Example 1, 2-hydroxy-3-naphthoic acid [3
-(2-ethylhexyloxy) anilide] was used to obtain a thermosensitive recording material in the same manner as in Example 1 except that an emulsion was obtained, and evaluated.

Table 2 shows the results of the λmax, image light fastness test and fixing property test of the image area.

[0122]

[Table 2]

From these results, it can be seen that the violet-cyan coloring type thermosensitive recording material using the pyrrolotriazinone compound represented by the general formula (1) of the present invention as a coupler has a high coloring density. Further, it can be seen that even after the light irradiation with the fluorescent lamp, the rate of decrease in the density of the image portion is small, and the image light resistance is excellent. Furthermore, when the background portion of the sample after the image fixing is heat-printed again, the color development is small, and it can be seen that the image fixing property is excellent. The hue was also improved.

[0124]

The heat-sensitive recording material of the present invention is a violet-cyan coloring type diazo heat-sensitive recording material, comprising a shelf life,
While image storability and image fixability have been greatly improved,
It has an excellent effect of improving the color hue.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsunori Matsushita 200 Fujinaka Film Co., Ltd., Fujinomiya City, Shizuoka Prefecture (72) Inventor Masatoshi Yumoto 200 Onakazato Fujinaka City, Fujinomiya City, Shizuoka Prefecture Fuji Photo Film Co., Ltd. (72) Inventor Yasuhiro Mitamura 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Inside Fuji Photo Film Co., Ltd. (72) Inventor Mitsuyuki Tsurumi 200 Onakazato, Fujinomiya City, Shizuoka Prefecture Fuji Photo Film Co., Ltd. F-term (reference) 2H026 AA07 BB42 BB43 CC10 FF05 4H056 EA05 FA03

Claims (5)

[Claims] 1. A diazonium salt compound on a support,
In a heat-sensitive recording material provided with a heat-sensitive recording layer containing the diazonium salt compound and a coupler that develops a color by reacting upon heating, at least one of a pyrrolotriazine-one compound represented by the following general formula (1) is used as the coupler. A heat-sensitive recording material comprising: Embedded image (Wherein R ¹ and R ² are each a hydrogen atom, an aryl group, an alkyl group, a cyano group, an acyl group, a substituted carbamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a substituted amino group, an alkylsulfonyl group, an arylsulfonyl A substituted or substituted sulfamoyl group;
R ³ is a hydrogen atom, a halogen atom, an aryl group, an alkyl group, an acyl group, an alkoxycarbonyl group,
Represents a substituted amino group, a hydroxy group, an alkoxy group, an aryloxy group, a mercapto group, an alkylthio group, or an arylthio group. ) 2. The heat-sensitive recording material according to claim 1, wherein the maximum absorption wavelength λmax of the diazonium salt compound is 450 nm or less. 3. The compound according to claim 1, wherein the diazonium salt compound is a compound represented by the following general formula (2) or / and / or general formula (3) or / and general formula (4). 2. The heat-sensitive recording material according to item 1. Embedded image (Wherein, Ar represents a substituted or unsubstituted aryl group,
R ¹¹ and R ¹² each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group.
R ¹¹ and R ¹² may be the same or different. X ^- represents an acid anion. ) (Wherein, R ¹⁴ , R ¹⁵ , and R ¹⁶ each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ¹⁴ , R ¹⁵ , and R ¹⁶ may be the same or different. Y represents a hydrogen atom or an —OR ¹³ group; R ¹³ represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group; and X ⁻ represents an acid anion.) Embedded image (In the formula, R ¹⁷ and R ¹⁸ each represent a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. X ⁻ represents an acid anion.) 4. The thermosensitive recording material according to claim 1, wherein the diazonium salt compound is encapsulated in a microcapsule. 5. The capsule wall of the microcapsule,
The heat-sensitive recording material according to any one of claims 1 to 4, which is a capsule wall containing polyurethane and / or polyurea as a constituent.