JPH09286782A - Thermal recording material and diazo compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermal recording material which gives a thermal recording layer containing a novel diazo compound excellent in resistance to light and having photofixation capability. SOLUTION: On the base material, is formed a thermally recording layer which contains a diazo compound of formula I[R<1> -R<4> are independently form each other H, an alkyl, an aryl, a halogen, CN, NO2 ; A is COSO2 ; B is SO2 R<11> (R<11> is an alkyl, an aryl), POR<12> R<13> (R<12> and R<13> are independently from each other an alkyl, an aryl, an alkoxy)] and a coupler compound which reacts with the diazo compound to develop a color. This compound of formula I is prepared, for example, by reaction of a diazotization of an amine of formula II followed by intramolecular cyclization. The compound of formula I is preferably capsulated in microcapsules.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a heat-sensitive recording material and a diazo compound, and more specifically, it has excellent light resistance and
The present invention relates to a heat-sensitive recording material using a novel diazo compound having light fixing property.

[0002]

2. Description of the Related Art Thermal recording has recently been developed because its recording apparatus is simple, highly reliable, and requires no maintenance. As the heat-sensitive recording material, those utilizing a reaction between an electron-donating colorless dye and an electron-accepting compound and those utilizing a reaction between a diazonium salt compound and a coupler have been widely known.

As a heat-sensitive recording material, in recent years, studies have been earnestly conducted to improve characteristics such as (1) color density and color sensitivity (2) fastness of color material.

However, the heat-sensitive recording material has a drawback that when exposed to sunlight for a long time or when it is displayed in an office for a long time, the background portion is colored by the light and the image portion is discolored or faded. Had.

Various methods have been proposed in order to improve the coloring of the background portion and the discoloration or fading of the image portion, but sufficient effects have not always been obtained.

Further, this heat-sensitive recording material has a problem that it is apt to be tampered with because the formed image and the background portion are discolored by chemicals and heat, and it is difficult to use it for storing important records. Therefore, there has been a demand for a heat-sensitive recording material that can impart photo-fixability and prevent alteration and tampering after image formation while making full use of the characteristics of the heat-sensitive recording material.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat-sensitive recording material having excellent light resistance and light fixing property.

[0008]

The above-mentioned object is to provide a thermosensitive recording material having a thermosensitive recording layer containing, on a support, a diazo compound and a coupler compound that reacts with the diazo compound to develop a color. This has been achieved by a heat-sensitive recording material containing a compound represented by the following general formula (I) as a compound.

[0009]

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In the formula, R ^{1 to} R ⁴ are each independently a hydrogen atom, an alkyl group, an aryl group, —OR ⁵ , —SR ⁶ ,
-NR ⁷ R ^8, -COR ^10, halogen atom, -SO ₂ R
^10, -CN, it represents a -NO _2. Here, R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group, an aryl group, and an acyl group, and R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, and an aryl group. Represents a sulfonyl group, and further includes R ⁷ and R
⁸ are linked to each other, -O -, - S -, - SO 2 -, -
Represents an alkylene group which may contain NR ⁹ —, R ⁹
Represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, and R
¹⁰ represents a hydrogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, or —NR ⁷ R ⁸ . Here, R ⁷ and R ⁸ have the same meaning as described above.

A represents --CO-- or --SO _2- ,
B represents ^{_{-SO 2 R 11, -POR 12 R}} 13, wherein, R
¹¹ is an alkyl group, an aryl group, a heterocyclic group, -NR ⁷ R
It represents ^8, R ¹² and R ¹³ each independently represents an alkyl group, an aryl group, an alkoxy group, an aryloxy radical, R
⁷ and R ⁸ have the same meaning as described above.

Further, the characteristics of the present invention are remarkable when the compound represented by the general formula (I) is encapsulated in microcapsules.

The diazo compound of the present invention is represented by the following general formula (I).

[0014]

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In the formula, R ^{1 to} R ⁴ are each independently a hydrogen atom, an alkyl group, an aryl group, —OR ⁵ , —SR ⁶ ,
-NR ⁷ R ^8, -COR ^10, halogen atom, -SO ₂ R
^10, -CN, it represents a -NO _2. Here, R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group, an aryl group, and an acyl group, and R ⁷ and R ⁸ each independently represent a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, and an aryl group. Represents a sulfonyl group, and further includes R ⁷ and R
⁸ are linked to each other, -O -, - S -, - SO 2 -, -
Represents an alkylene group which may contain NR ⁹ —, R ⁹
Represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, and R
¹⁰ represents a hydrogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, or —NR ⁷ R ⁸ . Here, R ⁷ and R ⁸ have the same meaning as described above.

A represents --CO-- or --SO _2- ,
B represents ^{_{-SO 2 R 11, -POR 12 R}} 13, wherein, R
¹¹ is an alkyl group, an aryl group, a heterocyclic group, -NR ⁷ R
It represents ^8, R ¹² and R ¹³ each independently represents an alkyl group, an aryl group, an alkoxy group, an aryloxy radical, R
⁷ and R ⁸ have the same meaning as described above.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

The compound represented by the above general formula (I) which is a color-forming component in the heat-sensitive recording material of the present invention will be described. Among the substituents in the above general formula (I), 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. Further, 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.

The compound represented by the above general formula (1) is a compound having a benzotriazine skeleton as is clear from the structure, but it is a cyclic derivative obtained by a diazotization reaction and is similar to the diazonium salt compound. In the present invention, it is referred to as a diazo compound for the sake of convenience because it has a light fixing property. It has not been known at all until now that the compound represented by the above general formula (1) is used in a heat-sensitive recording material and exhibits photofixability.

Among the substituents represented by R ^{1 to} R ⁴ , a hydrogen atom; an alkyl group having 1 to 18 carbon atoms; and 6 carbon atoms
To 18 aryl groups; halogen atoms such as fluorine atom, chlorine atom and bromine atom; R ⁵ is an alkyl group having 1 to 22 carbon atoms, an aryl group having 6 to 22 carbon atoms, and 2 carbon atoms.
~ OR ⁵ which is an acyl group of ~ 22; R ⁶ has 1 carbon atom.
To an alkyl group having from 22 to 22, an aryl group having from 6 to 22 carbon atoms, and an acyl group having from 2 to 22 carbon atoms, —SR ⁶ ; R
⁷ is a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, an aryl group having 6 to 22 carbon atoms, and R ⁸ is 1 to 2 carbon atoms.
An alkyl group having 2 to 6 carbon atoms, an aryl group having 6 to 22 carbon atoms, an acyl group having 2 to 22 carbon atoms, and R ⁷ and R ⁸ are linked to each other;
O -, - S -, - SO 2 -, - NR 9 - a which may contain an alkylene group having 4 to 10 carbon atoms, (wherein, R
⁹ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, -NR ⁷ R ⁸ is an acyl group having 2 to 18 carbon atoms is preferred); R ¹⁰ is a carbon atom An alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, an aryloxy group having 6 to 18 carbon atoms, -COR ¹⁰ and-
SO ₂ R ¹⁰ ; -CN; -NO ₂ is preferable, and particularly hydrogen atom; alkyl group having 1 to 12 carbon atoms;
12 aryl group; fluorine atom, chlorine atom; R ⁵ is an alkyl group having 1 to 16 carbon atoms, an aryl group having ⁶ to 16 carbon atoms —OR ⁵ ; R ⁶ is alkyl having 1 to 16 carbon atoms And an aryl group having 6 to 16 carbon atoms-
SR ⁶ ; R ⁷ is hydrogen atom, alkyl group having 1 to 16 carbon atoms, aryl group having 6 to 16 carbon atoms, R ⁸ is alkyl group having 1 to 16 carbon atoms, aryl having 6 to 16 carbon atoms A group, an acyl group having 2 to 16 carbon atoms, and R ⁷ and R ⁸ may be linked to each other to contain —O—, —S—, —SO ₂ —, and —NR ⁹ —; Is an alkylene group of -NR ⁷ R ⁸ ; R ¹⁰ is an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and 1 to 1 carbon atoms.
Alkoxy groups of the 12, -COR ¹⁰ and -SO ₂ R ¹⁰ is an aryloxy group having 6 to 12 carbon atoms; -CN;
-NO ₂ is preferred.

Further, in order to improve the efficiency of the optical fixing property, R ¹ to R ^1
At least one of ⁴ is -OR ⁵ , -SR ⁶ , -NR ⁷ R ⁸
It is preferred that

Of the substituents represented by B, R ¹¹ is an alkyl group having 1 to 22 carbon atoms and -N having 2 to 22 carbon atoms.
_{^{R 7 R 8, -SO 2 R}} 11 is a heterocyclic group containing an aryl group having a carbon number of 6 to 22, N, O or S; R ^12, R ¹³
Is preferably an alkyl group having 1 to 18 carbon atoms, an alkoxy group, an aryl group having 6 to 18 carbon atoms, or an aryloxy group, -POR ¹² R ¹³ is preferable, and particularly R ¹¹ is 1 carbon atom.
To 16 alkyl group, -SO ₂ R ¹¹ is an aryl group having a carbon number of 6~16, R ^12, R ¹³ is 1 to 12 carbon atoms
Is preferable, and -POR ¹² R ¹³ which is an aryloxy group having 6 to 12 carbon atoms is preferable. Further, —SO ₂ R ¹¹ is preferable from the viewpoint of reactivity with the coupler compound.

Specific examples of the above substituents are shown below, but the present invention is not limited thereto.

R ^{1 to} R ⁴ are hydrogen atom, phenyl group, tolyl group, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s
ec-butyl group, t-butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, allyl group, 2
-Butenyl group, benzyl group, α-dimethylbenzyl group,
Methoxy group, ethoxy group, propyloxy group, butyloxy group, octyloxy group, dodecyloxy group, octadecyloxy group, 2-ethylhexyloxy group, methoxyethoxy group, phenoxyethoxy group, 4-methoxyphenoxyethoxy group, phenoxy group, chloro group Phenoxy group, 4-octyloxyphenoxy group, acetyloxy group, butyryloxy group, benzoyloxy group, methylthio group, ethylthio group, butylthio group, hexylthio group,
Octylthio group, dodecylthio group, octadecylthio group, benzylthio co-, phenethylthio group, phenylthio group, tolylthio group, chlorophenylthio group, methoxyphenylthio group, dimethylamino group, diethylamino group,
Dipropylamino group, dibutylamino group, dioctylamino group, N-methyl-N-cyclohexylamino group, diphenylamino group, N-ethyl-N-tolylamino group,
Acetylamino group, propionylamino group, isobutyrylamino group, pivaloylamino group, myristoylamino group, stearoylamino group, acryloylamino group, benzoylamino group, cinnamoylamino group, morpholino group, piperidino group, pyrrolidino group, N-butyryl group Rupiperazino group, ethoxycarbonyl group, phenyloxycarbonyl group, carbamoyl group, fluorine atom, chlorine atom, bromine atom, sulfamoyl group, methanesulfonylamino group,
Benzenesulfonylamino group, octylaminosulfonyl group, phenylaminosulfonyl group, trifluoromethyl group, octylaminocarbonylmethyloxy group, di (butyloxycarbonylmethyl) amino group, di (dibutylaminocarbonylmethyl) amino group, dicyanoethylamino Group, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, octylsulfonyl group, phenylsulfonyl group, tolylsulfonyl group, chlorophenylsulfonyl group, butyloxyphenylsulfonyl group,
Examples thereof include a sulfo group, a methoxysulfonyl group, a phenoxysulfonyl group, a cyano group and a nitro group.

The substituent represented by B includes a methanesulfonyl group, an ethanesulfonyl group, a butanesulfonyl group,
Benzenesulfonyl group, 4-methylbenzenesulfonyl group, 2-mesitylenesulfonyl group, 4-methoxybenzenesulfonyl group, 4-octyloxybenzenesulfonyl group, 2,4,6-triisopropylbenzenesulfonyl group, β-styrenesulfonyl group, Vinylbenzenesulfonyl group, 4-chlorobenzenesulfonyl group, 2,5-
Dichlorobenzenesulfonyl group, 2,4,5-trichlorobenzenesulfonyl group, 1-naphthalenesulfonyl group, 2-naphthalenesulfonyl group, quinolinesulfonyl group, thiophenesulfonyl group, nitrobenzenesulfonyl group, cyanobenzenesulfonyl group, acetylaminobenzenesulfonyl group , Butoxycarbonylbenzenesulfonyl group, pentafluorobenzenesulfonyl group, trifluoromethanesulfonyl group, perfluorobutanesulfonyl group, camphorsulfonyl group, dimethylaminosulfonyl group, diphenylphosphoryl group, diethylphosphoryl group and the like.

The method for producing the compound represented by the general formula (1) includes diazotization of an amino compound represented by the following general formula and subsequent intramolecular cyclization,

[0027]

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Alternatively, X-B (where X represents a halogen atom) is added to the diazo compound represented by the following general formula and, if necessary, a base such as pyridine, triethylamine, potassium carbonate or sodium hydroxide. Examples thereof include a method of existence and a reaction.

[0029]

[Chemical 6]

R ^{1 to} R in the above general formulas
⁴ , A and B have the same meanings as in the general formula (1).

Specific examples of the compound represented by the general formula (1) are shown below, but the invention is not limited thereto. Further, these compounds can be used either alone or as a mixture of two or more kinds.

[0032]

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[0033]

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[0034]

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In the heat-sensitive recording material containing the compound represented by the general formula (I), in order to apply this compound, (1) a method in which it is used as a solid dispersion, and (2) it is used in an emulsified dispersion. There are a method, (3) a method of dispersing a polymer, a method of (4) a method of dispersing a latex, and a method of (5) microcapsulation. Is preferred.

The content of the compound represented by the general formula (I) is preferably 0.02 to 3.0 g / m ² ,
It is more preferably 0.1 to 2.0 g / m ² .
In this case, if the content is less than 0.02 g / m ² ,
If the color density is insufficient and the content is more than 3.0 g / m ² , coloring (stain) after photofixation becomes a problem.

Next, the method for incorporating the compound represented by formula (I) into the heat-sensitive recording material will be described in detail.

As a method of emulsifying and dispersing, first, the compound represented by the general formula (I) is dissolved in oil. This oil may be solid or liquid at room temperature, and may be a polymer, for example, acetic acid ester, methylene chloride, cyclohexanone or the like having a low boiling point auxiliary solvent and / or phosphoric acid ester, phthalic acid ester, acrylic acid ester, methacrylic acid ester, Other carboxylic acid ethesul, fatty acid amide, alkylated biphenyl, alkylated terphenyl, alkylated naphthalene, diarylethane, chlorinated paraffin, alcohol-based, phenol-based, ether-based, monoolefin-based, epoxy-based oils and the like can be mentioned. . Specific examples include tricresyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, tricyclohexyl phosphate, dibutyl phthalate, dioctyl phthalate, dilaurate phthalate, dicyclohexyl phthalate, butyl oleate, diethylene glycol benzoate, dioctyl sebacate, Dibutyl sebacate,
Dioctyl adipate, trioctyl trimellitate,
Acetyl triethyl citrate, octyl maleate, dibutyl maleate, isoamyl biphenyl, chlorinated paraffin, diisopropyl naphthalene, 1,1'-ditolylethane, 2,4-di-t-amylphenol, N, N
-Dibutyl-2-butoxy-5-t-octylaniline, hydroxybenzoic acid 2-ethylhexyl ester,
High boiling point oils such as polyethylene glycol and α-methylstyrene dimer can be mentioned. Among them, alcohol type, phosphoric acid ester type, carboxylic acid type ester type, alkylated biphenyl, alkylated terphenyl,
Alkylated naphthalene and diarylethane are preferred.
Further, an antioxidant such as hindered phenol or hindered amine may be added to the high boiling point oil.

The oil solution containing the compound of the above general formula (I) is added to an aqueous solution of a water-soluble polymer and emulsified and dispersed by a colloid mill, a homogenizer or ultrasonic waves.
As the water-soluble polymer used at this time, a water-soluble polymer such as polyvinyl alcohol is used, but an emulsion or latex of a hydrophobic polymer may be used in combination. As the water-soluble polymer, polyvinyl alcohol, silanol modified polyvinyl alcohol, carboxy modified polyvinyl alcohol, amino modified polyvinyl alcohol, itaconic acid modified polyvinyl alcohol, styrene-maleic anhydride copolymer, butadiene-maleic anhydride copolymer, ethylene -Maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, polyacrylamide, polystyrene sulfonic acid, polyvinylpyrrolidone, ethylene-acrylic acid copolymer, gelatin and the like, and among these, especially carboxy-modified polyvinyl alcohol preferable. Examples of the emulsion or latex of the hydrophobic polymer include a styrene-butadiene copolymer, a carboxy-modified styrene-butadiene copolymer, an acrylonitrile-butadiene copolymer and the like. At this time, a conventionally known surfactant or the like may be added, if necessary, for the purpose of improving the emulsion stability.

As a method of microencapsulating the compound represented by the general formula (I), a conventionally known method of microencapsulation can be used. That is, the compound of the general formula (I) and the microcapsule wall precursor are dissolved in an organic solvent that is sparingly soluble or insoluble in water, added to an aqueous solution of a water-soluble polymer, emulsified and dispersed using a homogenizer, etc. A polymer substance that becomes a microcapsule wall upon heating can be prepared by forming a wall film at the oil / water interface.
Specific examples of the polymer substance that becomes the wall film of the microcapsule include, for example, polyurethane resin, polyurea resin, polyamide resin, polyester resin, polycarbonate resin, aminoaldehyde resin, melamine resin, polystyrene resin, styrene-acrylate copolymer resin, Examples thereof include styrene-methacrylate copolymer resin, gelatin, polyvinyl alcohol and the like, and mixtures thereof. Particularly preferable among these are microcapsules having a wall film made of a polyurethane-polyurea resin.

Microcapsules having a wall film made of polyurethane / polyurea resin are prepared by mixing a microcapsule wall precursor such as polyisocyanate with a core substance to be encapsulated and emulsifying it in an aqueous solution of a water-soluble polymer such as polyvinyl alcohol. It is manufactured by dispersing and raising the liquid temperature to cause a polymer formation reaction at the oil drop interface.

Here, some of the specific examples of the polyisocyanate compound as the microcapsule wall precursor are shown below. For example, m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-
4,4'-diisocyanate, 3,3'-diphenylmethane-4,4'-diisocyanate, xylene-1,4
-Diisocyanate, 4,4'-diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, butylene-1,2-diisocyanate, cyclohexylene-1,2-diisocyanate, cyclohexylene-1, Diisocyanates such as 4-diisocyanate, 4,4 ′, 4 ″ -triphenylmethane triisocyanate, triisocyanates such as toluene-2,4,6-triisocyanate, 4,4′-dimethyldiphenylmethane-2,2 ′ , 5,5'-Tetraisocyanate and other tetraisocyanates, addition product of hexamethylene diisocyanate and trimethylolpropane, addition of 2,4-tolylene diisocyanate and trimethylolpropane , An isocyanate prepolymer such as an adduct of xylylene diisocyanate and trimethylolpropane, an adduct of tolylene diisocyanate and hexanetriol, etc. In addition, two or more kinds of them may be used in combination, if necessary. Particularly preferred is one having three or more isocyanate groups in the molecule.

In the method of microencapsulation, as the organic solvent in which the compound represented by the general formula (I) is dissolved,
The oils exemplified in the emulsification and dispersion method can be used. The same applies to a water-soluble polymer.

The particle size of the microcapsules is 0.1 to 1.0.
μm is preferable, and more preferably 0.2 to 0.7 μm.

In the heat-sensitive recording layer containing the diazo compound represented by the general formula (I) used in the present invention and the coupler compound which reacts with the compound to develop a color, a base which further promotes the color reaction is formed. Substances, sensitizers that improve thermal sensitivity,
It may contain an antioxidant for improving the fastness, a UV absorber, a metal salt capable of chelating the formed dye and a metal complex, or a precursor thereof.

As the coupler which is used in the present invention and exhibits a color upon thermal reaction with the diazonium compound represented by the above general formula (I), known naphthol derivatives, hydroxynaphthoic acid derivatives, phenol derivatives, pyrazolone derivatives,
1,3-diketone derivative, ketocarboxamide derivative,
A pyrazolotriazole derivative, a hydrazone derivative, a hydroxycoumarin derivative, a barbituric acid derivative and the like can be used, and for example, US Pat. No. 1,969,479 can be used.
No. 3,265,506, No. 4,486,52
No. 7, No. 4,659,644, British Patent No. 2,19
6,141, JP-A-61-273986, and JP-A-6-273986.
4-67379, 59-160136, etc. are mentioned. Specific examples include resorcin, flurglucin, sodium 2,3-dihydroxynaphthalene-6-sulfonate, 1-hydroxy-2-naphthoic acid morpholinopropylamide, 1,5-dihydroxynaphthalene, 2,3-dihydroxynaphthalene,
2,3-dihydroxy-6-sulfanylnaphthalene,
2-Hydroxy-3-naphthoic acid anilide, 2-hydroxy-3-naphthoic acid ethanolamide, 2-hydroxy-3-naphthoic acid octylamide, 2-hydroxy-
3-naphthoic acid-N-dodecyloxypurupyramide,
2-hydroxy-3-naphthoic acid tetradecylamide,
Acetanilide, acetoacetanilide, benzoylacetanilide, 2-chloro-5-octylacetoacetanilide, 1-phenyl-3-methyl-5-pyrazolone, 1- (2'-octylphenyl) -3-methyl-5.
-Pyrazolone, 1- (2 ', 4', 6'-trichlorophenyl) -3-benzamido-5-pyrazolone, 1-
(2 ′, 4 ′, 6′-Trichlorophenyl) -3-anilino-5-pyrazolone, 1-phenyl-3-phenylacetamido-5-pyrazolone, and further C-1 to
Examples thereof include C-6 compounds. These couplers are 2
It is also possible to obtain a desired color hue by combining two or more kinds.

[0047]

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The basic substance includes not only an inorganic or organic basic compound, but also a compound which decomposes upon heating to release an alkaline substance. Typical examples include organic ammonium salts, organic amines, amides, urea and thiourea, and their derivatives, thiazoles,
Pyrroles, pyrimidines, piperazines, guanidines, indoles, imidazoles, imidazolines,
Examples thereof include nitrogen-containing compounds such as triazoles, morpholines, piperidines, amidines, formazines and pyridines. Specific examples thereof include tricyclohexylamine, tribenzylamine, octadecylbenzylamine, stearylamine, allylurea, thiourea, methylthiourea, allylthiourea, ethylenethiourea, 2-benzylimidazole, 4-phenylimidazole, 2-phenyl. -4-Methylimidazole, 2-undecylimidazoline, 2,4,5-trifuryl-2-
Imidazoline, 1,2-diphenyl-4,4-dimethyl-2-imidazoline, 2-phenyl-2-imidazoline, 1,2,3-triphenylguanidine, 1,2-dicyclohexylguanidine, 1,2,3-tri Cyclohexyl guanidine, guanidine trichloroacetate, N,
There are N'-dibenzylpiperazine, 4,4'-dithiomorpholine, morpholinium trichloroacetate, 2-aminobenzothiazole, 2-benzoylhydrazinobenzothiazole and the like. These can be used in combination of two or more.

The sensitizers usable in the present invention include phenols, ethers, esters, sulfonamides,
Examples thereof include amides, ureas, urethanes, alcohols and the like. Specific examples thereof include 1,1- (4-hydroxyphenyl) -2-2-ethylhexane, benzyloxynaphthalene, toluenesulfonamide, butoxybenzenesulfonamide, 1,2-phenoxyethane, diphenylurea, benzamide, stearin. Acid amide and the like can be mentioned. These can be used in combination of two or more.

In the present invention, the diazo compound represented by the above general formula (I), the coupler which reacts with the compound under heat to develop a color, the basic substance, and, if desired, the sensitizer may be used in the following forms. There is no particular limitation. That is, as in the case of the compound of the general formula (I), (1) a method of using by solid dispersion, (2) a method of using by emulsion dispersion, (3)
There are methods such as polymer dispersion, (4) latex dispersion, and (5) microencapsulation. Among them, microcapsulation is used from the viewpoint of preservability. The method is preferable, and the case where the diazo compound represented by the general formula (I) is microencapsulated is particularly preferable.

In the present invention, the following known antioxidants can be used in order to further improve the light resistance. For example, European Patent Publication No. 310,551 and German Patent Publication No. 3,435,443. Publication, European Patent Publication No. 310,552, Japanese Patent Laid-Open No. 3-1
21449, European Published Patent No. 459,41
6, JP-A-2-262654, JP-A-2-
71262, JP-A-63-163351,
U.S. Pat. No. 4,814,262, JP-A-54-485.
35, JP-A-5-61166, and 5-11.
9449, U.S. Pat. No. 4,980,275, Japanese Patent Laid-Open No. 63-113536, 62-262047.
Publication, European patent publication 223,739 publication,
Examples thereof include those disclosed in European Patent Publication No. 309,402 and European Patent Publication No. 309,401.

Further, it is also effective to use various additives already known as heat-sensitive recording materials and pressure-sensitive recording materials. If some of these antioxidants are shown, they are disclosed in JP-A-60-1.
25470, JP-A-60-125471,
JP-A-60-125472, JP-A-60-287
485, JP 60-287486, JP 60-287487, and JP 62-14668.
No. 0, JP-A-60-287488, JP-A-6
2-2828585, JP-A-63-89877, JP-A-63-88380, and JP-A-63-08.
8381, JP 01-239282 A, JP 04-291685 A, JP 04-2916 A.
No. 84, No. 05-1888687, No. 05-188686, No. 05-110490.
Japanese Patent Laid-Open No. 05-1108437 and Japanese Patent Laid-Open No.
5-170361, JP-A-63-203372, JP-A-63-224989, JP-A-63-
267594, JP-A-63-182484, JP-A-60-107384, and JP-A-60-1.
No. 07383, JP-A No. 61-160287,
JP-A-61-185483 and JP-A-61-2111
079, JP-A-63-251282, JP-A-63-051174, JP-B-48-04329.
The compounds described in Japanese Patent Publication No. 4 and Japanese Patent Publication No. 48-033212 are listed.

Specific examples include 6-ethoxy-1-phenyl-2,2,4-trimethyl-1,2-dihydroquinoline, 6-ethoxy-1-octyl-2,2,4-trimethyl-1,2. -Dihydroquinoline, 6-ethoxy-1-
Phenyl-2,2,4-trimethyl-1,2,3,4-
Tetrahydroquinoline, 6-ethoxy-1-octyl-
2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline, nickel cyclohexanoate, 2,2-bis-4-hydroxyphenylpropane, 1,1-bis-4
-Hydroxyphenyl-2-ethylhexane, 2-methyl-4-methoxy-diphenylamine, 1-methyl-2
-Phenylindole and the compounds shown below.

[0054]

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[0055]

[Chemical 12]

[0056]

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[0057]

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[0058]

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[0059]

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[0060]

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[0061]

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These antioxidants can be added to the heat-sensitive recording layer, the intermediate layer or the protective layer. When these antioxidants and the like are used in combination, for example, specific examples (Q-
7), (Q-45), (Q-46) or compound (Q-1)
0) and the compound (Q-13) in combination.

Examples of the UV absorber or its precursor include conventionally known hydroxybenzophenones, cinnamic acid esters, salicylic acid esters, benzotriazoles and triazines. Specific examples thereof include the compounds shown below, but the invention is not limited thereto.

[0064]

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The UV absorber or its precursor can be added to the protective layer, the thermosensitive coloring layer or the intermediate layer by emulsifying dispersion, polymer dispersion, latex dispersion, solid dispersion or microencapsulation.

As the binder in the present invention, conventionally known binders can be used, and examples thereof include water-soluble polymers such as polyvinyl alcohol and gelatin, and polymer latex.

As the support in the present invention, plastic film, paper, plastic resin laminated paper, synthetic paper and the like can be used.

In the present invention, when heat-sensitive color-developing layers having different hues are laminated, an intermediate layer can be provided in order to prevent color mixture. A water-soluble polymer compound is used for the intermediate layer. Examples thereof include polyvinyl alcohol, modified polyvinyl alcohol, methyl cellulose, sodium polystyrene sulfonate, styrene-maleic acid copolymer, gelatin and the like.

In the protective layer of the present invention, various pigments, release agents and the like can be added in addition to the same water-soluble polymer compound as the intermediate layer.

The constitution of the heat-sensitive recording material to which the present invention is applied is not particularly limited, and two or more compounds represented by the general formula (I) having different maximum absorption wavelengths are used to prepare a multi-color heat-sensitive recording material. Obtainable. Further, the above general formula (I)
In addition to the compound represented by, another coloring system, for example, a coloring system of an electron-donating colorless dye and an electron-accepting compound, a diazonium salt compound and a coupler compound that develops a color when reacted with the diazonium salt compound To obtain a multicolor thermosensitive recording material even in combination with a color-developing system, a base color-developing system which develops a color upon contact with a basic compound, a chelate color-developing system, and a color-developing system which reacts with a nucleophile to cause an elimination reaction to produce a color You can These may exist in the same layer or may be laminated in different layers. Examples of the multicolor heat-sensitive recording material include, for example,
(i) A heat-sensitive recording layer containing, on a support, a diazo compound represented by the above general formula (I) having a maximum absorption wavelength of 360 ± 20 nm and a coupler that reacts with the compound to develop a color, and a maximum absorption wavelength. A heat-sensitive recording material in which a heat-sensitive recording layer containing a compound represented by the general formula (I) having a wavelength of 400 ± 20 nm and a coupler which reacts with the compound to develop a color is sequentially provided,
i) A heat-sensitive recording layer containing, on a support, a compound represented by the general formula (I) having a maximum absorption wavelength of 400 ± 20 nm and a coupler that reacts with the compound to develop a color, and a maximum absorption wavelength of 360 ± A heat-sensitive recording material in which a heat-sensitive recording layer containing a compound represented by the general formula (I) having a thickness of 20 nm and a coupler that reacts with the compound to produce a color is sequentially provided, (iii) a maximum absorption wavelength of less than 340 nm A thermosensitive recording layer containing a compound represented by the general formula (I) and a coupler that reacts with the compound to develop a color, and a compound represented by the general formula (I) having a maximum absorption wavelength of more than 420 nm. A thermosensitive recording layer comprising a thermosensitive recording layer containing a coupler which reacts with the compound to develop a color, and (iv) a support having a maximum absorption wavelength of 4
A thermosensitive recording layer containing a diazo compound represented by the general formula (I) having a wavelength of 00 ± 20 nm and a coupler which reacts with the compound to develop a color, a diazonium salt compound having a maximum absorption wavelength of 360 ± 20 nm, and the diazonium. A thermosensitive recording material in which a thermosensitive recording layer containing a coupler which reacts with the salt compound to develop a color is provided in order, (v) a diazonium salt compound having a maximum absorption wavelength of 400 ± 20 nm on the support, and the diazonium salt compound A thermosensitive recording layer containing a coupler that reacts and develops a color, a thermosensitive recording layer containing a compound represented by the general formula (I) having a maximum absorption wavelength of 360 ± 20 nm, and a coupler that reacts with the compound to develop a color. A thermosensitive recording material in which layers are sequentially provided, and the like can be mentioned.

The maximum absorption wavelength of the compound represented by the general formula (I) or the compound represented by the general formula (I) and the diazonium salt compound having two or more different photosensitive wavelengths is limited to the wavelengths exemplified above. It is not a matter of fact that the maximum absorption wavelengths of each are separated by at least 20 nm or more,
It is preferable from the viewpoint that the optical fixing can be sequentially performed.

In the present invention, the maximum absorption wavelength of the compound represented by the general formula (I) or the diazonium salt compound is 0.1 g / m ² to 1.0 g / m ² for each compound.
The spectrophotometer those in coating of m ² (manufactured by Shimadzu Corporation, M
PS-2000).

In the present invention, the above-mentioned thermosensitive recording layers may be laminated and applied, and a multicolor thermosensitive recording material can be obtained by changing the hue of each thermosensitive recording layer.

Although the layer structure is not particularly limited, for example, two kinds of the above general formula (I) having different photosensitive wavelengths are used.
2 layers of a thermosensitive recording layer in which a compound represented by the formula (1) and a coupler that reacts with each of the compounds under heat to develop different hues are combined, and a thermosensitive recording layer in which an electron-donating colorless dye and an electron-accepting compound are combined. And a multicolor heat-sensitive recording material in which and are laminated. That is, a first heat-sensitive recording layer containing an electron-donating colorless dye and an electron-accepting compound on a support, a compound represented by the above general formula (I) having a maximum absorption wavelength of 360 ± 20 nm, the compound and the heat A second heat-sensitive recording layer containing a coupler which reacts with time to give a color, and has a maximum absorption wavelength of 40.
The third heat-sensitive recording layer contains a compound represented by the general formula (I) having a wavelength of 0 ± 20 nm and a coupler that reacts with the compound to produce a color when heated. In this example,
If the coloring hue of each heat-sensitive recording layer is selected to be the three primary colors in subtractive color mixing, yellow, magenta, and cyan,
Full-color image recording is possible.

In the recording method of this multicolor heat-sensitive recording material, first, the third heat-sensitive recording layer is heated, and the compound represented by the general formula (I) and the coupler contained in the third layer are colored. Then, light of 400 ± 20 nm is irradiated to decompose the unreacted compound contained in the third thermosensitive recording layer, and then the second
Sufficient heat is applied to the thermosensitive recording layer to develop color, whereby the compound represented by the general formula (I) contained in the layer and the coupler are developed. At this time, the third heat-sensitive recording layer is also heated strongly at the same time, but the compound represented by the general formula (I) has already been decomposed and the color forming ability is lost, so that no color is formed. Further, the compound contained in the second thermosensitive recording layer is decomposed by irradiating with light of 360 ± 20 nm, and finally the first
The heat-sensitive recording layer is colored by applying sufficient heat.
At this time, the third and second thermosensitive recording layers are also heated strongly at the same time, but since each compound represented by the general formula (I) has already been decomposed and the coloring ability is lost, no color is produced.

Specific examples of the diazonium salt compound that can be used in the heat-sensitive recording material of the present invention include 4- (N-
(2- (2,4-di-tert-amylphenoxy) butyryl) piperazino) benzenediazonium, 4-dioctylaminobenzenediazonium, 4- (N- (2-
Ethylhexanoyl) piperazino) benzenediazonium, 4-dihexylamino-2-hexyloxybenzenediazonium, 4-N-ethyl-N-hexadecylamino-2-ethoxybenzodiazonium, 3-chloro-
4-Dioctylamino-2-octyloxyobenzenediazonium, 2,5-dibutoxy-4-morpholinobenzenediazonium, 2,5-octoxy-4-morpholinobenzenediazonium, 2,5-dibutoxy-4-
(N- (2-ethylhexanoyl) piperazino) benzenediazonium, 2,5-diethoxy-4- (N- (2
-(2,4-di-tert-amylphenoxy) butyryl) piperazino) benzenediazonium, 2,5-dibutoxy-4-tolylthiobenzenediazonium, 3-
Examples thereof include acid anion salts such as (2-octyloxyethoxy) -4-morpholinobenzenediazonium and the following diazonium salt compounds D-1 to D-5. Especially hexafluorophosphate salt, tetrafluoroborate salt,
1,5-naphthalene sulfonate salts are preferred.

[0077]

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In the present invention, as the color-forming component used in the heat-sensitive recording layer, a compound represented by the above formula (I), a compound utilizing the reaction of the above-mentioned diazonium salt compound and a coupler, and an electron-donating colorless compound are used. Examples of the electron-donating colorless dye used in the heat-sensitive recording material of the present invention include triarylmethane compounds, diphenylmethane compounds, and thiazine compounds. , Xanthene-based compounds, spiropyran-based compounds, and the like. Triarylmethane-based compounds and xanthene-based compounds are particularly useful because of their high color density. For example, some of these are 3,3-
Bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (that is, crystal violet lactone), 3,3-bis (p-dimethylamino) phthalide,
3- (p-dimethylaminophenyl) -3- (1,2-
Dimethylindol-3-yl) phthalide, 3- (p-
Dimethylaminophenyl) -3- (1-octyl-2-
Methylindol-3-yl) phthalide, 3- (o-methyl-p-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide, 4,4′-bis ( Dimethylamino) benzhydrin benzyl ether, N-halophenyl leuco auramine, N-2,4,5-trichlorophenyl leuco auramine, rhodamine-B-anilinolactam, rhodamine (p-nitroanilino) lactam, rhodamine-B. −
(P-chloroanilino) lactam, 2-benzylamino-6-diethylaminofluorane, 2-anilino-6-
Diethylaminofluorane, 2-anilino-3-methyl-6-diethylaminofluorane, 2-anilino-3-
Methyl-6-cyclohexylmethylaminofluorane,
2-anilino-3-methyl-6-isoamylethylaminofluorane, 2- (o-chloroanilino) -6-diethylaminofluorane, 2-octylamino-6-diethylaminofluorane, 2-ethoxyethylamino-3
-Chloro-2-diethylaminofluorane, 2-anilino-3-chloro-6-diethylaminofluorane, benzoylleuco methylene blue, p-nitrobenzyl leuco methylene blue, 3-methyl-spiro-dinaphthopyran, 3-ethyl-spiro-dinaphthopyran, 3,3'-
Dichloro-spiro-dinaphthopyran, 3-benzylspirodinaphthopyran, 3-propyl-spiro-dibenzopyran and the like can be mentioned.

Examples of electron-accepting compounds include phenol derivatives, salicylic acid derivatives, hydroxybenzoic acid esters and the like. Particularly, bisphenols and hydroxybenzoic acid esters are preferable. Examples of some of these include 2,2-bis (p-hydroxyphenyl) propane (ie, bisphenol A), 4,4 ′-(p-
Phenylenediisopropylidene) diphenol (ie,
Bisphenol P), 2,2-bis (p-hydroxyphenyl) pentane, 2,2-bis (p-hydroxyphenyl) ethane, 2,2-bis (p-hydroxyphenyl) butane, 2,2-bis (4 '-Hydroxy-3',
5'-dichlorophenyl) propane, 1,1- (p-hydroxyphenyl) cyclohexane, 1,1- (p-hydroxyphenyl) propane, 1,1- (p-hydroxyphenyl) pentane, 1,1- (p- Hydroxyphenyl) -2-ethylhexane, 3,5-di (α-methylbenzyl) salicylic acid and its polyvalent metal salt, 3,5-di (tert-butyl) salicylic acid and its polyvalent metal salt,
3-α, α-dimethylbenzyl salicylic acid and its polyvalent metal salts, butyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, 2-ethylhexyl p-hydroxybenzoate, p-phenylphenol, p-cumylphenol And so on.

[0080]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

All "parts" in this example are "parts by weight".

Synthesis of Diazo Compound (Production Example-) Synthesis of Compound of Specific Example (1) 1,2,3-benzotriazin-4-one 20 mmol, 2,4,5-trichlorobenzenesulfonyl chloride 22 mmol, acetone Put 30 ml in a three-necked flask, and cool with ice.
Mmol was added dropwise, and the mixture was stirred at room temperature for 2 hours.

200 ml of water was added to the reaction product,
The precipitated crystals were filtered and washed with methanol to give a specific example (1).
7.1 g of the diazo compound represented by (Decomposition point 1
35 ° C)

Synthesis of Compound of Specific Example (2) Diazo compound represented by the following formula: 30 mmol, triethylamine: 36 mmol, acetonitrile: 50 ml
Was placed in a three-necked flask, 33 mmol of benzenesulfonyl chloride was added dropwise under ice cooling, and the mixture was stirred at room temperature for 2 hours.

150 ml of water was added to the reaction product,
The precipitated crystals were filtered and washed with methanol to give a specific example (2).
7.8 g of a diazo compound represented by (Decomposition point 1
60 ° C)

[0086]

[Chemical 21]

Synthesis of Compound of Specific Example (7) Diazo compound represented by the following formula: 30 mmol, benzenesulfonyl chloride: 33 mmol, acetone: 60 m
1 was placed in a three-necked flask, 33 mmol of a 24% aqueous sodium hydroxide solution was added dropwise under ice cooling, and the mixture was stirred under ice cooling for 2 hours.

100 ml of water and 20 ml of ethyl acetate were added to the reaction product, the organic phase was washed with water and dried over magnesium sulfate, and then the solvent was distilled off. The residue is ethyl acetate / n-
By applying a silica gel column with hexane, 5.7 g of the diazo compound represented by the specific example (7) was obtained. (Decomposition point 102 ° C)

[0089]

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Synthesis of Compound of Specific Example (11) Diazo compound represented by the following formula: 20 mmol, 24%
Aqueous sodium hydroxide solution 23 mmol, acetone 4
0 ml was placed in a three-necked flask, 22 mmol of methanesulfonyl chloride was added dropwise under ice cooling, and the mixture was stirred at room temperature for 2 hours.

100 ml of water was added to the reaction product,
The precipitated crystals were filtered and washed with methanol to give a concrete example (1
6.3 g of the diazo compound represented by 1) was obtained. (Decomposition point 155 ° C)

[0092]

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Synthesis of Compound of Specific Example (12) Diazo compound represented by Specific Example (12) in the same manner as in Production Example except that 4-chlorobenzenesulfonyl chloride was used instead of methanesulfonyl chloride in the Production Example. 7.4 g was obtained. (Decomposition point 177 ° C)

Synthesis of Compound of Specific Example (17) Diazo compound represented by the following formula: 20 mmol, 24%
Aqueous sodium hydroxide solution 22 mmol, acetone 4
0 ml was placed in a three-neck flask, 22 mmol of 2,5-dimethylbenzenesulfonyl chloride was added dropwise under ice cooling, and the mixture was stirred at room temperature for 2 hours.

100 ml of water was added to the reaction product,
The precipitated crystals were filtered and washed with methanol to give a concrete example (1
7.3 g of the diazo compound represented by 7) was obtained. (Decomposition point 141 ° C)

[0096]

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Synthesis of Compound of Specific Example (25) The same procedure as in Production Example except that chlorophosphonic acid di-2-ethylhexyl ester was used in place of methanesulfonyl chloride in the above Production Example was carried out. 7 g of an oily diazo compound was obtained.

Preparation and Evaluation of Thermosensitive Recording Material [Evaluation Criteria] The reflection density was measured using a reflection density meter RD918 manufactured by Macbeth. The photo-fixing property of the diazo heat-sensitive recording layer was evaluated by confirming that after the fixing operation by irradiation of light for a predetermined time, heat of 86 mJ / mm ² was applied again to the non-printed part and no color was developed (that is, it was fixed). Was done. Those that were fixed were evaluated as ◯, and those that developed color (that is, not fixed) were evaluated as x.

The light resistance was evaluated by using a weather ometer (WEAT
HERO METER CI 65: Product name, ATLAS ELECTRIC DEVICES
(Manufactured by CO.) Was applied to a sample irradiated with 0.9 W / m ² for 48 hours, and the residual ratio of the dye in the image area was determined by the following formula and evaluated.

Residual rate (%) of image area = [(reflection density after light irradiation) / (reflection density before light irradiation)] × 100 It is judged that the higher the residual rate of the dye is, the more excellent the light resistance is.

[Example 1] [Preparation of thermosensitive recording layer liquid] (Preparation of diazo compound capsule liquid) 2.8 parts of the compound shown in Specific Example (10) as diazo compound, 2.8 parts of dibutyl sulfate, 2, 2-dimethoxy-1,2-diphenylethan-1-one (IRGACURE 651: trade name, Ciba.
0.56 parts (manufactured by Geigy) was dissolved in 19.0 parts of ethyl acetate. Furthermore, 5.9 parts of isopropyl biphenyl, which is a high boiling point solvent, and 2.5 parts of tricresyl phosphate were added to the above liquid, and heated to uniformly mix. As a capsule wall agent, xylylene diisocyanate / trimethylolpropane adduct (75% ethyl acetate solution Takenate D1)
7.6 parts (10N: manufactured by Takeda Pharmaceutical Co., Ltd.) was further added to this solution and stirred uniformly. Separately, prepare 64 parts of a 6% by weight gelatin (MGP-9066: trade name, manufactured by Nippi Gelatin Industry Co., Ltd.) aqueous solution containing 2.0 parts of a 10% by weight sodium dodecylsulfonate aqueous solution, and add the above diazonium salt compound solution. Then, it was emulsified and dispersed by a homogenizer. After 20 parts of water was added to the obtained emulsion to homogenize it, the temperature was raised to 40 ° C. with stirring, and an encapsulation reaction was performed for 3 hours.
Thereafter, the liquid temperature is lowered to 35 ° C., 6.5 parts of ion-exchange resin Amberlite IRA68 (manufactured by Organo) and 13 parts of Amberlite IRC50 (manufactured by Organo) are added, and the mixture is further stirred for one hour. Thereafter, the ion exchange resin was filtered to obtain a desired capsule liquid. The average particle size of the capsule is 0.66 μm
Met.

(Preparation of Emulsion Dispersion of Coupler) As a coupler, 3.0 parts of compound b-1 shown below, 4.0 parts of triphenylguanidine, and 1,1- (p-hydroxyphenyl) -2-ethylhexane were used. 4.0 parts, 4,4 '-(p
-Phenylene diisopropylidene) diphenol
0 part, 2-ethylhexyl-4-hydroxybenzoate 8.0 parts, b-2 as an antioxidant 2.0 parts,
1,1,3-tris (2-methyl-4-hydroxy-5)
(T-butylphenyl) butane (2.0 parts) was dissolved in ethyl acetate (10.5 parts), and a high boiling solvent tricresyl phosphate (0.48 part) and diethyl maleate (0.24 part) were further dissolved.
1.27 parts of Pionein A41C (manufactured by Takemoto Yushi Co., Ltd.) was added and then heated and mixed uniformly. Separately, it was added to 93 parts of an aqueous solution of 8% by weight gelatin (# 750 gelatin: manufactured by Nitta Gelatin Co., Ltd.) and emulsified and dispersed by a homogenizer. The remaining ethyl acetate was evaporated from this emulsion to obtain the target emulsion dispersion.

[0103]

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(Preparation of coating liquid) The diazo compound capsule liquid, the coupler emulsion dispersion, and the styrene-butadiene rubber (SBR: SN307: trade name, manufactured by Sumitomo Nogatak Co., Ltd.) were each used at a diazo compound / coupler ratio of 1.
And a diazo compound / styrene-butadiene rubber ratio of 1 / 6.4 were mixed to prepare a desired coating liquid.

[Preparation of Protective Layer] 20.5 wt% zinc stearate dispersion liquid (Hydrin F115: trade name) in 61 parts of 5.0 wt% carboxy-modified polyvinyl alcohol (KL-318: manufactured by Kuraray Co., Ltd.) aqueous solution. , Manufactured by Chukyo Yushi Co., Ltd.), 8.4 parts of a 2% by weight aqueous solution of a compound represented by the following formula c-1 and ME which is a fluorine-based releasing agent.
-313 (manufactured by Daikin) and 8.0 parts of wheat starch KF-4 (manufactured by Kagoshima Starch) were added and stirred uniformly. This is called mother liquor. Separately, ion-exchanged 20% by weight aqueous solution of chaogros (Shiraishi Industry Co., Ltd.) 1
2.5 parts, Poise 532A (manufactured by Kao) 0.06 part, Hydrin Z-7 (manufactured by Chukyo Yushi Co., Ltd.) 1.87 parts, 10% by weight polyvinyl alcohol (PVA105: manufactured by Kuraray Co., Ltd.)
1.25 parts and 0.39 part of a 2 wt% sodium dodecyl sulfonate aqueous solution were mixed and finely dispersed with a dyno mill. This liquid is called a pigment liquid. Mother liquor 80
4.4 parts of the pigment liquid is added to the above parts and stirred for 30 minutes or more. After that, Wetmaster 500 (manufactured by Toho Chemical Co., Ltd.) 2.
8 parts was added and further stirred for 30 minutes or more to obtain the target coating liquid.

[0106]

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[Preparation of Heat-Sensitive Recording Material] A heat-sensitive recording layer containing a compound represented by the above general formula (I) by means of a Meyer bar and a protective layer were formed in this order on a photographic paper support obtained by laminating polyethylene on high-quality paper. The desired heat-sensitive recording material was obtained by sequentially applying and drying. The coating amounts as solids were 8.40 g and 1.23 g per 1 m ^2, respectively.

(Thermal recording) Kyocera thermal head KST
Using a mold, (1) the recording energy per unit area is 6
The applied power to the thermal head and the pulse width were determined so as to be ² mJ / mm ^2, and when the thermal recording material was printed, it developed an orange color. Then, this thermosensitive recording material was placed under an ultraviolet lamp with an emission center wavelength of 365 nm and an output of 40 W for 20 minutes.
It was exposed for 0 seconds and fixed.

Example 2 A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that the compound of Example (7) was used in place of Example (10). . When the heat-sensitive recording material was printed, it developed a yellow color. Example 3 A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that the compound of Example (17) was used in place of Example (10). When the heat-sensitive recording material was printed, it developed a yellow color.

Example 4 A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that the compound of Example (13) was used in place of Example (10). . When the heat-sensitive recording material was printed, it developed an orange color. Example 5 In Example 1, the compound of the specific example (13) is used in place of the specific example (10), and the compound b shown below is used instead of the compound represented by the compound b-1 as a coupler.
A thermal recording material was prepared and evaluated in the same manner as in Example 1 except that -3 was used. When the heat-sensitive recording material was printed, it developed a magenta color.

[0111]

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Example 6 In Example 1, the compound of the specific example (9) was used in place of the specific example (10), and the compound b-shown below was used as a coupler instead of the compound represented by the compound b-1. A thermal recording material was prepared and evaluated in the same manner as in Example 1 except that No. 4 was used. When the heat-sensitive recording material was printed, it developed a reddish brown color.

[0113]

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Example 7 In Example 1, except that the compound of the specific example (13) was used in place of the specific example (10), and acetoacetanilide was used as the coupler in place of the compound represented by the compound b-1. In the same manner as in Example 1, a thermal recording material was prepared and evaluated. When the heat-sensitive recording material was printed, it developed a yellow color.

[Comparative Example 1] A specific example (1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that the compound a-1 shown below was used instead of the compound (0). When the heat-sensitive recording material was printed, it developed a magenta color.

[0116]

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[Comparative Example 2] A concrete example (1
A thermosensitive recording material was prepared and evaluated in the same manner as in Example 1 except that the compound a-2 shown below was used instead of the compound (0). When the heat-sensitive recording material was printed, it developed an orange color.

[0118]

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[Comparative Example 3] A concrete example (1
A thermal recording material was prepared and evaluated in the same manner as in Example 1 except that the compound a-3 shown below was used in place of the compound of (0). When the heat-sensitive recording material was printed, it developed a yellow color.

[0120]

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The evaluation results of the thermal recording materials of Examples 1 to 7 and Comparative Examples 1 to 3 are shown in Table 1 below.

[0122]

[Table 1]

As is clear from Table 1, all of Examples 1 to 7, which are heat-sensitive recording materials using the diazo compound of the present invention, have good photofixability and the residual rate of dye in the image area. And the light resistance of the image area was excellent.

On the other hand, in Comparative Examples 1 and 2 which are heat-sensitive recording materials using known diazo compounds, the photofixability is good, but the light resistance of the image area is insufficient, and the general formula (1) Comparative Example 3, which has a benzotriazine skeleton similar to the compound represented by I) but is a diazo compound outside the scope of the present invention, has no problem in the light fastness of the image area, but has a light fixing property. It turns out that they don't have.

[0125]

INDUSTRIAL APPLICABILITY As described above, the heat-sensitive recording material of the present invention containing the novel diazo compound according to the present invention in the heat-sensitive recording layer is said to have excellent light resistance in the image area and to have optical fixing. It showed an excellent effect.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03C 1/54 C07D 285/00

Claims (3)

[Claims] 1. A heat-sensitive recording material comprising a support and a heat-sensitive recording layer containing a diazo compound and a coupler compound which reacts with the diazo compound to develop a color, wherein the diazo compound is represented by the following general formula (I): A heat-sensitive recording material comprising the compound represented. Embedded image In the formula, R ^{1 to} R ⁴ are each independently a hydrogen atom, an alkyl group, an aryl group, —OR ⁵ , —SR ⁶ , or —NR ⁷ R
^8, -COR ^10, halogen atom, -SO ₂ R ^10, -C
N, representing the -NO _2. Here, R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group, an aryl group, or an acyl group,
R ⁷ and R ⁸ are each independently a hydrogen atom, an alkyl group,
It represents an aryl group, an acyl group, an alkylsulfonyl group, or an arylsulfonyl group, and R ⁷ and R ⁸ are linked to each other to include —O—, —S—, —SO ₂ —, and —NR ⁹ —. R ⁹ represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, and R ¹⁰ represents a hydrogen atom, a hydroxyl group, an alkyl group. Represents a group, an aryl group, an alkoxy group, an aryloxy group, and —NR ⁷ R ⁸ . here,
R ⁷ and R ⁸ have the same meaning as described above. Also, A is −
CO -, - SO ₂ -, B stands -SO ₂ R ^11, -PO
Represents R ¹² R ^13, wherein, R ¹¹ is an alkyl group, an aryl group, a heterocyclic group, an -NR ⁷ R ^8, R ¹² and R ¹³ each independently represents an alkyl group, an aryl group, an alkoxy group,
It represents an aryloxy group, and R ⁷ and R ⁸ have the same meaning as described above. 2. The heat-sensitive recording material according to claim 1, wherein the compound represented by the general formula (I) is encapsulated in microcapsules. 3. A diazo compound represented by the following general formula (I). Embedded image In the formula, R ^{1 to} R ⁴ are each independently a hydrogen atom, an alkyl group, an aryl group, —OR ⁵ , —SR ⁶ , or —NR ⁷ R
^8, -COR ^10, halogen atom, -SO ₂ R ^10, -C
N, representing the -NO _2. Here, R ⁵ and R ⁶ each represent a hydrogen atom, an alkyl group, an aryl group, or an acyl group,
R ⁷ and R ⁸ are each independently a hydrogen atom, an alkyl group,
It represents an aryl group, an acyl group, an alkylsulfonyl group, or an arylsulfonyl group, and R ⁷ and R ⁸ are linked to each other to include —O—, —S—, —SO ₂ —, and —NR ⁹ —. R ⁹ represents a hydrogen atom, an alkyl group, an aryl group, an acyl group, an alkylsulfonyl group, an arylsulfonyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, and R ¹⁰ represents a hydrogen atom, a hydroxyl group, an alkyl group. Represents a group, an aryl group, an alkoxy group, an aryloxy group, and —NR ⁷ R ⁸ . here,
R ⁷ and R ⁸ have the same meaning as described above. Also, A is −
CO -, - SO ₂ -, B stands -SO ₂ R ^11, -PO
Represents R ¹² R ^13, wherein, R ¹¹ is an alkyl group, an aryl group, a heterocyclic group, an -NR ⁷ R ^8, R ¹² and R ¹³ each independently represents an alkyl group, an aryl group, an alkoxy group,
It represents an aryloxy group, and R ⁷ and R ⁸ have the same meaning as described above.