JP2871875B2 - Thermal recording material - Google Patents

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 having excellent light resistance and good image storability especially before recording.

[0002]

2. Description of the Related Art In recent years, heat-sensitive recording materials which record by thermal energy are used in a wide range of fields such as printers and recorders for various measuring instruments, printers for labels, printers for POS, and automatic ticket vending machines such as tickets. It has become. However, conventional heat-sensitive recording materials using an electron-donating colorless dye precursor and an electron-accepting color developer have excellent appearance, good feel, high color density, and various color hues. While having characteristics,
The recorded image area (thermosensitive coloring area) comes in contact with plastics such as polyvinyl chloride and disappears due to plasticizers and additives contained in plastics, or comes in contact with chemicals contained in foods and cosmetics There were drawbacks in that the storage stability of the record was poor, such as disappearing easily or fading easily upon exposure to sunlight for a short time. In view of this point, JP-A-58-387 discloses a heat-sensitive recording material which reacts when two components are heated to obtain a recorded image having good storability.
No. 33, JP-A-58-54085, JP-A-5-54085
Japanese Patent Application Laid-Open No. 8-104959 discloses a heat-sensitive recording material in which two components comprise an isocyanate compound and an imino compound.

[0003]

However, heat-sensitive recording materials comprising these imino compounds and isocyanate compounds are excellent in the preservability of recorded images, but are colored on the entire surface when exposed to light for a long time. There is a disadvantage of doing so. Recently, heat-sensitive recording materials have been used in various fields as receipts, notices, and the like, and thus improvements have been strongly desired. In view of this situation, the present invention aims to develop an image recording material having excellent light fastness.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to obtain a heat-sensitive recording material having excellent light fastness and excellent image storability. As a result, a heat-sensitive recording material comprising an aromatic isocyanate compound and an imino compound was obtained. By using an ultraviolet absorber of a benzotriazole-based compound having one or more halogen atoms in an aromatic ring in the recording material, a heat-sensitive recording material with excellent image storability having excellent light resistance can be obtained. I was able to.

The benzotriazole-based compound used in the present invention is represented by the general formula 1 wherein R _{1 to} R ₈ are a hydrogen atom, a halogen atom, a C _{1 to} C ₈ alkyl group, and a C _{1 to} C ₈ alkoxy group, respectively. A phenyl group, a benzyl group or a benzyloxy group, at least one of which is a halogen atom). Specific examples are shown below.

[0006]

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2- (2'hydroxy-3 ', 5'-di-
tert-butylphenyl) -5-chloro-benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-
5'-methylphenyl) -5-chloro-benzotriazole and the like.

Conventionally, various methods have been proposed for improving the light fastness of an ultraviolet absorber in a heat-sensitive recording material. For example, heat-sensitive recording materials to which benzotriazole-based and benzophenone-based ultraviolet absorbers are added are described in JP-A-55-93942 and JP-A-58-87093.
It is disclosed in JP-A-2-273287. However, the benzotriazoles used in the present invention can be appropriately selected from known ones, but are specifically benzotriazoles having one or more halogen atoms in the aromatic ring.
The effect of improving the light fastness was observed in the chloro-based compound.

The benzotriazoles according to the present invention comprise 0.5% to 20% by weight, preferably 1% to 10% by weight, based on the total solid content of the heat-sensitive recording layer. If it is less than 0.5% by weight, the effect of improving light resistance is insufficient.

The aromatic isocyanate compound used in the present invention refers to a colorless or pale-colored aromatic isocyanate compound or heterocyclic isocyanate compound which is a solid at room temperature, and for example, one or more of the following are used.

2,6-dichlorophenyl isocyanate, p-chlorophenyl isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 1,3-dimethylbenzene-4,6-diisocyanate, 1,4-dimethylbenzene-2,5-diisocyanate, 1-methoxybenzene-2,4-diisocyanate, 1-methoxybenzene-2,5-diisocyanate, 1-ethoxybenzene-2,4- Diisocyanate, 2,5-dimethoxybenzene-1,4-diisocyanate, 2,5-diethoxybenzene-1,4-diisocyanate, 2,5-dibutoxybenzene-1,4
-Diisocyanate, azobenzene-4,4'-diisocyanate, diphenylether-4,4'-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, naphthalene-
2,6-diisocyanate, naphthalene-2,7-diisocyanate, 3,3′-dimethyl-biphenyl-4,
4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenyldimethylmethane-4,4'-diisocyanate, benzophenone-
3,3'-diisocyanate, fluorene-2,7-diisocyanate, anthraquinone-2,6-diisocyanate, 9-ethylcarbazole-3,6-diisocyanate, pyrene-3,8-di Isocyanate, naphthalene-1,3,7-triisocyanate, biphenyl-
2,4,4'-triisocyanate, 4,4'4 "-triisocyanate-2,5-dimethoxytriphenylamine, p-dimethylaminophenyl isocyanate, tris (4-phenylisocyanate) thiophosphate and the like These isocyanate compounds may be used, if necessary, in the form of so-called block isocyanates, which are addition compounds with phenols, lactams, oximes and the like, and diisocyanate dimers. For example, it may be used in the form of 1-methylbenzene-2,4-diisocyanate dimer and trimer isocyanurate, or used as a polyisocyanate adducted with various polyols and the like. It is also possible.

The imino compound used in the present invention is a compound represented by the general formula 2 (φ is an aromatic compound residue capable of forming a conjugated system with adjacent C ＝ N), It is a colorless or pale compound. Specific examples are shown below. Two or more imino compounds can be used in combination depending on the purpose.

[0013]

Embedded image

3-iminoisoindoline-1-one, 3
-Imino-4,5,6,7-tetrachloroisoindoline-1-one, 3-imino-4,5,6,7-tetrabromoisoindoline-1-one, 3-imino-4,5
6,7-tetrafluoroisoindoline-1-one, 3
-Imino-5,6-dichloroisoindoline-1-one, 3-imino-4,5,7-trichloro-6-methoxy-isoindoline-1-one, 3-imino-4,5,
7-trichloro-6-methoxy-isoindoline-1-
On, 3-imino-4,5,7-trichloro-6-methylmercapto-isoindoline-1-one, 3-imino-6-nitroisoindoline-1-one, 3-imino-
Isoindoline-1-spiro-dioxolan, 1,1-
Dimethoxy-3-imino-isoindoline, 1,1-diethoxy-3-imino-4,5,6,7-tetrachloroisoindoline, 1-ethoxy-3-imino-isoindoline, 1,3-diiminoiso Indoline, 1,3-diimino-4,5,6,7-tetrachloroisoindoline, 1,3-diimino-6-methoxyisoindoline,
1,3-diimino-6-cyanoisoindoline, 1,3
-Diimino-4,7-dithia-5,5,6,6-tetrahydroisoindoline, 7-amino-2,3-dimethyl-5-oxopyrrolo [3,4b] pyrazine, 7-amino-2,3-diphenyl -5-oxopyrrolo [3, 4b]
Pyrazine, 1-iminonaphthalimide, 1-iminodiphenimide, 1-phenylimino-3-iminoisoindoline, 1- (3′-chlorophenylimino) -3
-Iminoisoindoline, 1-{(2 ', 5'-dichlorophenylimino) -3-iminoisoindoline, 1-
(2 ', 4', 5'trichlorophenylimino) -3-
Iminoisoindoline, 1- (2'-cyano-4'-nitrophenylimino) -3-iminoisoindoline, 1
-(2'-chloro-5'-cyanophenylimino) -3
-Iminoisoindoline, 1- (2'6'-dichloro-
4'-nitrophenylimino) -3-iminoisoindoline, 1- (2 ', 5'-dimethoxyphenylimino)
-3-iminoisoindoline, 1- (2 ', 5'-diethoxyphenylimino) -3-iminoisoindoline,
1- (2'-methyl-4'-nitrophenylimino)-
3-iminoisoindoline, 1- (5'-chloro-2 '
-Phenoxyphenylimino) -3-iminoisoindoline, 1- (4'-N, N-dimethylaminophenylimino) -3-iminoisoindoline, 1- (3'-N,
N-dimethylamino-4'-methoxyphenylimino)
-3-iminoisoindoline, 1- (2'-methoxy-
5'-N-phenylcarbamoylphenylimino) -3
-Iminoisoindoline, 1- (2'-chloro-5'-
Trifluoromethylphenylimino) -3-iminoisoindoline, 1- (5'6'-dichlorobenzothiazolyl-2'-imino) -3-iminoisoindoline, 1-
(6′-methylbenzothiazolyl-2′-imino) -3
-Iminoisoindoline, 1- (4'-phenylaminophenylimino) -3-iminoisoindoline, 1-
(P-phenylazophenylimino) -3-iminoisoindoline, 1- (naphthyl-1′-imino) -3-iminoisoindoline, 1- (anthraquinone-1′-imino) -3-iminoisoindoline, 1- (5'-chloroanthraquinone-1'-imino) -3-iminoisoindoline, 1- (N-ethylcarbazolyl-3'-imino) -3-iminosoindoline, 1- (naphthoquinone-
1′-imino) -3-iminoisoindoline, 1- (pyridyl-4′-imino) -3-iminoisoindoline,
1- (benzimidazolone-6′-imino) -3-iminoisoindoline, 1- (1′-methylbenzimidazolone-6′-imino) -3-iminoisoindoline, 1
-(7'-chlorobenzimidazolone-5'-imino)
-3-iminoisoindoline, 1- (benzimidazolyl-2'-imino) -3-iminoisoindoline, 1-
(Benzimidazolyl-2′-imino) -3-imino-
4,5,6,7-tetrachloroisoindoline, 1-
(2 ′, 4′-dinitrophenylhydrazone) -3-iminoisoindoline, 1- (indazolyl-3′-imino) -3-iminoisoindoline, 1- (indazolyl-3′-imino) -3-imino- 4,5,6,7-tetrabromoisoindoline, 1- (indazolyl-3'-
Imino) -3-imino-4,5,6,7-tetrafluoroisoindoline, 1- (benzimidazolyl-2'-
Imino) -3-imino-4,7-dithiatetrahydroisoindoline, 1- (4 ', 5'-dicyanoimidazolyl-2'-imino) -3-imino-5,6-dimethyl-
4,7-pyradioisoindoline, 1-{(cyanobenzoylmethylene) -3-iminoisoindoline, 1- (cyanocarbonamidomethylene) -3-iminoisoindoline, 1- (cyanocarbomethoxymethylene) -3- Iminoisoindoline, 1- (cyanocarboethoxymethylene) -3-iminoisoindoline, 1- (cyano-N
-Phenylcarbamoylmethylene) -3-iminoisoindoline, 1- [cyano-N- (3'-methylphenyl) carbamoylmethylene] -3-iminoisoindoline, 1- [cyano-N- (4'-chlorophenyl) carbamoyl Methylene] -3-iminoisoindoline, 1-
[Cyano-N-{(4'-methoxyphenyl) -carbamoylmethylene] -3-iminoisoindoline, 1-
[Cyano-N- (3'-chloro-4'-methylphenyl) -carbamoylmethylene] -3-iminoisoindoline, 1- (cyano-p-nitrophenylmethylene)-
3-iminoisoindoline, 1- (dicyanomethylene)
-3-iminoisoindoline, 1- (cyano-1 ',
2 ′ 4′-triazolyl-{(3 ′)-carbamoylmethylene) -3-iminoisoindoline, 1- (cyanothiazoyl- (2 ′)-carbamoylmethylene) -3-iminoisoindoline, 1- (cyanobenzimidazolyl-
(2) (2 ')-carbamoylmethylene, -3-iminoisoindoline, 1- (cyanobenzothiazolyl (2')-
Carbamoylmethylene) -3-iminoisoindoline,
1-[(cyanobenzimidazolyl-2 ′)-methylene] -3-iminoisoindoline, 1-[(cyanobenzimidazolyl-2 ′) methylene] -3-imino-4,
5,6,7-tetrachloroisoindoline, 1-[(cyanobenzimidazolyl-2 ')-methylene] -3-imino-5-methoxyisoindoline, 1- [cyanobenzimidazolyl-2') methylene] -3 -Imino-6-
Chloroisoindoline, 1-[(1′-phenyl-3 ′
-Methyl-5-oxo) -pyrazolidene-4 ']-3-
Iminoisoindoline, 1-[(cyanobenzimidazolyl-2 ')-methylene] -3-imino-4,7-dithiatetrahydroisoindoline, 1-[(cyanobenzimidazolyl-2')-methylene] -3- Imino-5
6-dimethyl-4,7-pyradiisoindoline, 1-
[(1′-methyl-3′-n-butyl) -barbituric acid-5 ′]-3-iminoisoindoline, 3-imino-1
-Sulfobenzoimide, 3-imino-1-sulfo-6
-Chlorobenzoic imide, 3-imino-1-sulfo-
5,6-dichlorobenzoic imide, 3-imino-1-sulfo-4,5,6,7-tetrachlorobenzoic imide,
3-imino-1-sulfo-4,5,6,7-tetrabromobenzoic imide, 3-imino-1-sulfo-4,5,
6,7-tetrafluorobenzoic imide, 3-imino-
1-sulfo-6-nitrobenzoic acid imide, 3-imino-
1-sulfo-6-methoxybenzoic imide, 3-imino-1-sulfo-4,5,7-trichloro-6-methylmercaptobenzoic imide, 3-imino-1-sulfonaphthoic imide, 3-imino-1 -Sulfo-5-bromonaphthoic imide, 3-imino-2-methyl-4,5,
6,7-tetrachloroisoindoline-1-one and the like.

As the support used in the heat-sensitive recording material of the present invention, paper is mainly used. In addition to paper, various non-woven fabrics, woven fabrics, synthetic resin films, laminates, synthetic papers, metal foils, or the like, The combined composite sheet can be used arbitrarily according to the purpose.

The layer structure of the heat-sensitive recording layer may be only the heat-sensitive recording layer. If necessary, a protective layer may be provided on the heat-sensitive recording layer, or an intermediate layer may be provided between the heat-sensitive recording layer and the support. In this case, the protective layer and / or the intermediate layer may be composed of two or three or more layers. Further, a back coat layer can be provided on the surface of the support opposite to the surface on which the heat-sensitive recording layer is provided, for the purpose of preventing curling and charging.

The heat-sensitive recording layer can be obtained by mixing each aqueous dispersion obtained by finely pulverizing each color-forming component, a binder and the like, coating the mixture on a support and drying. In this case, for example, each color-forming component may be contained one layer at a time to form a multilayer structure.

The heat-sensitive recording material according to the present invention can contain a heat-fusible substance in order to improve its thermal response. Those having a melting point of 60 ° C to 180 ° C are preferred, and those having a melting point of 80 ° C to 140 ° C are particularly preferred. For example, benzyl p-benzyloxybenzoate, stearic acid amide, palmitic acid amide, N-methylol stearic acid amide, β-naphthylbenzyl ether, N-stearyl urea, N, N′-distearyl urea, phenyl β-naphthoate Ester, 1-hydroxy-2-naphthoic acid phenyl ester, β-naphthol (p-methylbenzyl) ether, 1,4-dimethoxynaphthalene, 1-methoxy-4-benzyloxynaphthalene, N-stearoylurea, 4-benzylbiphenyl 1,2-di (m-methylphenoxy) ethane, 1-
Phenoxy-2- (4-chlorophenoxy) ethane,
Examples include 1,4-butanediol phenyl ether, dimethyl terephthalate, and the like.

The above-mentioned heat-fusible substance may be used alone or as a mixture. In order to obtain a sufficient thermal response, the heat-fusible substance is used in an amount of 10 to 300 to the aromatic isocyanate compound.
% By weight, and more preferably from 20 to 250% by weight.

Further, the heat-sensitive recording material according to the present invention may contain an aniline derivative having at least one amino group described in International Application No. PCT / JP81 / 00300 by the present applicant. More effective.

These compounds include methyl p-aminobenzoate, ethine p-aminobenzoate, n-propyl p-aminobenzoate, iso-propyl p-aminobenzoate, butyl p-aminobenzoate, dodecyl p-aminobenzoate, benzyl p-aminobenzoate, o-aminobenzophenone, m-aminoacetophenone, p-aminoacetophenone, m-aminobenzamide, o-aminobenzamide, p-aminobenzamide, p-amino-N- Methylbenzamide, 3-amino-4-methylbenzamide, 3-amino-4-methoxybenzamide,
3-amino-4-chlorobenzamide, p- (N-phenylcarbamoyl) aniline, p- [N- (4-chlorophenyl) carbamoyl] aniline, p- [N- (4-
Aminophenyl) carbamoyl] aniline, 2-methoxy-5- (N-phenylcarbamoyl) aniline, 2
-Methoxy-5- [N- (2'-methyl-3'-chlorophenyl) carbamoyl] aniline, 2-methoxy-5
-[N- (2'-chlorophenyl) carbamoyl] aniline, 5-acetylamino-2-methoxyaniline, 4
-Acetylaminoaniline, 4- (N-methyl-N-acetylamino) aniline, 2,5-diethoxy-4-
(N-benzoylamino) aniline, 2,5-dimethoxy-4- (N-benzoylamino) aniline, 2-methoxy-4- (N-benzoylamino) -5-methylaniline, 4-sulfamoylaniline, 3 -Sulfamoylaniline, 2- (N-ethyl-N-phenylaminosulfonyl) aniline, 4-dimethylaminosulfonylaniline, 4-diethylaminosulfonylaniline, sulfathiazole, 4-aminodiphenylsulfone, 2-
Chloro-5-N-phenylsulfamoylaniline, 2
-Methoxy-5-N, N-diethylsulfamoylaniline, 2,5-dimethoxy-4-N-phenylsulfamoylaniline, 2-methoxy-5-benzylsulfonylaniline, 2-phenoxysulfonylaniline, 2-
(2′-chlorophenoxy) sulfonylaniline, 3-
Anilinosulfonyl-4-methylaniline, bis [4-
(M-aminophenoxy) phenyl] sulfone, bis [4- (p-aminophenoxy) phenyl] sulfone,
Bis [3-methyl-4- (p-aminophenoxy) phenyl] sulfone, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2, 2'-dichloro-4,4'diamino-5,5'-dimethoxybiphenyl, 2,2'5
5'-tetrachloro-4,4'-diaminobiphenyl,
Ortho trisulfone, 2,4'-diaminobiphenyl, 2,2'-diaminobiphenyl, 4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diaminobiphenyl, 3,3'-dichloro- 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-thiodianiline, 2,2 '
-Dithiodianiline, 4,4'-dithiodianiline,
4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane,
3,4′-diaminodiphenylmethane, bis (3-amino-4-chlorophenyl) sulfone, bis (3,4-diaminophenyl) sulfone, bis (4-aminophenyl) sulfone, bis (3-aminophenyl) sulfone,
3,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylmethane, 4,4'-ethylenedianiline, 4,4'-diamino-2,2'-dimethyldibenzyl, 4,4'-diamino-3 , 3'-dichlorodiphenylmethane, 3,3'-diaminobenzophenone, 4,
4'-diaminobenzophenone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis {(4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9- Bis (4-aminophenyl) fluorene, 2,2-bis (4-aminophenoxyphenyl) propane, 4,4'-bis (4-aminophenoxy) diphenyl, 3,3 ', 4,4'-tetraaminodiphenyl ether , 3,3 ', 4,4'-tetraaminodiphenylsulfone, 3,3', 4,4'-tetraaminobenzophenone, and the like.

Further, pigments such as diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, titanium oxide, zinc oxide, silicon oxide, aluminum hydroxide, urea-formalin resin, etc. For the purpose of preventing head abrasion, sticking, etc., higher fatty acid metal salts such as zinc stearate and calcium stearate, waxes such as paraffin, paraffin oxide, polyethylene, polyethylene oxide, stearic acid amide, caster wax, and dioctyl sulfo succinate. A dispersing agent such as sodium acid, a surfactant, a fluorescent dye, and the like can also be contained.

[0023]

The present invention is characterized in that a benzotriazole-based compound having one or more chlorine atoms in an aromatic ring is contained in a heat-sensitive recording material. The ultraviolet absorber does not significantly inhibit the hot color development reaction between the aromatic isocyanate compound and the imino compound. Therefore, by including the benzotriazole-based compound in the heat-sensitive recording layer, it was possible to impart light resistance to a heat-sensitive recording material comprising an aromatic isocyanate compound and an imino compound and having excellent image preservability.

[0024]

The present invention will be described in more detail with reference to the following examples.

Example 1 15 g of 1,3-diimino-4,5,6,7-tetrachloroisoindoline was added to a 1% aqueous solution of polyvinyl alcohol 6
0g together with a ball mill for 24 hours.
10 g of 4,4 "-triisocyanato-2,5-dimethoxytriphenylamine was ground with a ball mill for 24 hours together with 40 g of a 1% aqueous solution of polyvinyl alcohol to obtain a dispersion. 2-methoxy-5-N, N-diethylsulfur 0.4 g of Famoylaniline was pulverized in the same manner with 20 g of a 1% aqueous solution of polyvinyl alcohol, and 21 g of 4-hydroxymethylbiphenyl was similarly pulverized together with 125 g of a 1% aqueous solution of polyvinyl alcohol. 0.4 g of -73 (manufactured by Chemipro Kasei Kogyo Co., Ltd.) was pulverized together with 40 g of a 1% aqueous polyvinyl alcohol solution to obtain respective dispersions.
125 g of a 0% aqueous dispersion, 50 g of a 30% aqueous dispersion of zinc stearate, 10% aqueous solution of polyvinyl alcohol 135
g and 90 g of water were added and sufficiently stirred to obtain a coating liquid. This coating solution was applied to a base paper having a basis weight of 50 g / m ^{2 in} a solid content of 5.2.
It was coated so as to obtain a coating amount of g / m ² , dried, and then treated with a super calender to obtain a heat-sensitive recording material.

Examples 2 to 3 A heat-sensitive recording material was obtained in the same manner as in Example 1, except that the following ultraviolet absorber was used instead of KEMISORB-73 as the ultraviolet absorber. In addition, Example 2 using KEMISORB-72 (manufactured by Chemipro Kasei Kogyo Co., Ltd.) was used.
Example 3 using TINUVIN-326 (manufactured by Ciba Geigy) was used.

Comparative Example 1 A heat-sensitive recording material was obtained in the same manner as in Example 1 except that the ultraviolet absorbent KEMISORB-73 of Example 1 was not used.

Comparative Example 2 A heat-sensitive recording material was obtained in the same manner as in Example 1 except that TINUVIN-P (manufactured by Ciba Geigy) was used instead of KEMISORB-73 of Example 1.

Comparative Example 3 Instead of KEMISORB-73 of Example 1, TINUVIN-11
A thermosensitive recording material was obtained in the same manner as in Example 1, except that 30 (manufactured by Ciba Geigy) was used.

Comparative Example 4 Instead of KEMISORB-73 of Example 1, KEMISORB-11
A heat-sensitive recording material was obtained in the same manner as in Example 1 except that S (manufactured by Chemipro Kasei Kogyo Co., Ltd.) was used.

Test 1 (Light fastness test) The heat-sensitive recording materials obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were irradiated for 24 hours under a fluorescent lamp of 32,000 lux for 24 hours, and thereafter, using a densitometer Macbeth RD918. The magenta density was measured to evaluate the fog density. At this time, it is preferable that the value of the optical density is small.

Test 2 (Coloring Density) The heat-sensitive recording materials obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were respectively applied with a heat-sensitive facsimile printing tester with an applied pulse of 1.1 milliseconds and an applied voltage of 22.00. Print under the condition of bolts and measure the density of the obtained color image with a densitometer Macbeth R
It was measured using D918. Examples 1-3, Comparative Examples 1
Table 1 shows the test results of Test No. 4.

[0033]

[Table 1]

[0034]

As shown in Table 1, in a heat-sensitive recording material comprising an aromatic isocyanate compound and an imino compound, a benzotriazole-based compound having one or more halogen atoms in the aromatic ring according to the present invention is used. By using this, a heat-sensitive recording material having excellent light stability and good image storability can be obtained.

Continuation of front page (56) References JP-A-62-176880 (JP, A) JP-A-63-67180 (JP, A) JP-A-61-54982 (JP, A) JP-A-4-144786 (JP) JP-A-63-248885 (JP, A) WO 87/6885 (WO, A1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41M 5/28-5/34

Claims (1)

(57) [Claims] 1. A heat-sensitive recording material having a heat-sensitive recording layer comprising an aromatic isocyanate compound and an imino compound provided on a support, comprising a benzotriazole-based compound having one or more halogen atoms in an aromatic ring. A heat-sensitive recording material characterized in that: