JPH0784101B2 - Multicolor thermal recording material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a multicolor thermosensitive recording material, and more particularly to a two-color thermosensitive recording material obtained by laminating a plurality of thermosensitive coloring layers having different color tones.

[Prior art]

The heat-sensitive recording material is one in which a heat-sensitive color forming layer capable of forming a color-formed image by heating is provided on a support such as paper, and a thermal printer equipped with a thermal head is widely used for heating. As such a conventional heat-sensitive recording material, a lactone ring, a lactam ring,
A colorless or light-colored leuco dye having a spiropyran ring (main coloring agent) and a developer that develops a color by reacting with this leuco dye when heated (coloring auxiliary agent) have a clear color tone and have a fogging effect. It is often used because it has few phenomena.

By the way, the thermosensitive recording material is not only used for copying books, documents, etc., because a colored image can be easily obtained only by heating it, but it is also used in various fields such as electronic calculators, facsimiles, telexes, etc. Depending on the purpose of recording, it is desirable to be able to record the color of that part (display color) differently from the color of other parts in order to display the necessary data and numbers more clearly depending on the recording application. It is natural.

Recently, attempts have been made to obtain multicolor recording by utilizing the difference in heating temperature or the difference in thermal energy, and various multicolor thermosensitive recording papers have been proposed accordingly. The multicolor color thermosensitive recording paper is generally formed by stacking two kinds of high-temperature and low-temperature color-developing layers, which are colored in different colors with different color-developing heat energies, on a support. It is divided into types. One is to obtain a color tone different from the color tone of the low temperature color layer by mixing with the color tone of the low temperature color layer when the high temperature color layer is colored, and the other one is
When a high-temperature color-developing layer is colored, a decoloring agent that decolors the low-temperature color-developing layer is used to obtain only the color-developing color tone of the high-temperature color-developing layer without the color mixture of the low-temperature color-developing layer. As specific examples of these, the former are disclosed in Japanese Patent Publication No. 49-69 and Japanese Patent Publication No. 49-49.
-4342, JP-B-49-27708, JP-A-48-86543, JP-A-49-65239, etc., and the latter are described in JP-B-50-17865 and JP-B- 50-17866, Japanese Patent Publication No. 51-29024, Japanese Patent Publication No. 51-87542,
These are disclosed in JP-A-50-18048 and JP-B-55-36519, respectively.

However, in the case of the former multicolor thermosensitive recording paper,
In the case of high-temperature color development, the color tone that can be specifically realized to mix with the color tone of the low-temperature color layer is such that the high-temperature color tone such as red-black, blue-black, etc. is limited to a black type with a strong tone. There is. On the other hand, in the latter case of the multicolor thermosensitive recording paper, the decoloring speed of the low temperature color developing layer is an important point for obtaining multicolor. Although such a decoloring speed depends on the decoloring agent, it also largely depends on the dye and the color developing agent.
Also, the color developability is greatly influenced by the decoloring agent, the dye and the color developing agent. Therefore, the quality is required to be such that the color developability is stable in temperature and humidity and the color erasing speed is fast.

BPA, benzyl p-hydroxybenzoate, and the like, which are well known as developers, have drawbacks such as low concentration and slow decoloring speed.

〔Purpose〕

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multicolor thermosensitive recording material which overcomes the above-mentioned problems of the prior art and is excellent in the color developability of the low temperature color developing layer and in the decoloring property.

〔Constitution〕

According to the present invention, in a multicolor thermosensitive recording material in which a high-temperature color-developing layer, a color-erasing layer, and a low-temperature color-developing layer are laminated in this order on a support,
There is provided a multicolor heat-sensitive recording material comprising a compound having a structure represented by the following general formula (I) as a developer of a low temperature color developing layer.

(In the formula, X: halogen or hydrogen R: alkyl group or aryl group) Examples of the developer of the general formula used in the present invention include compounds shown below.

Ethyl bis (3-chloro-4-hydroxyphenyl) acetate, isopropyl bis (3-chloro-4-hydroxyphenyl) acetate, butyl bis (3-chloro-4-hydroxyphenyl) acetate, bis (3-chloro-4-) Phenyl hydroxyphenyl) acetate, methyl bis (3-chloro-4-hydroxyphenyl) acetate, naphthyl bis (3-chloro-4-hydroxyphenyl) acetate, isoamyl bis (3-chloro-4-hydroxyphenyl) acetate, bis ( 3-chloro-4-hydroxyphenyl) acetic acid-n
-Nonyl, ethyl bis (3-chloro-4-hydroxyphenyl) acetate, isopropyl bis (3-bromo-4-hydroxyphenyl) acetate, butyl bis (3-bromo-4-hydroxyphenyl) acetate, bis (3-bromo Phenyl-4-hydroxyphenyl) acetate, naphthyl bis (3-bromo-4-hydroxyphenyl) acetate, isoamyl bis (3-bromo-4-hydroxyphenyl) acetate, bis (3-bromo-4-hydroxyphenyl) acetic acid- n
-Nonyl, methyl bis (3-bromo-4-hydroxyphenyl) acetate, ethyl bis (4-hydroxyphenyl) acetate, isopropyl bis (4-hydroxyphenyl) acetate, butyl bis (4-hydroxyphenyl) acetate, bis (4 -Hydroxyphenyl) phenyl acetate, bis (4-hydroxyphenyl) methyl acetate, bis (4-hydroxyphenyl) naphthyl acetate, bis (4-hydroxyphenyl) isoamyl acetate, bis (4-hydroxyphenyl) acetic acid-n-nonyl.

These compounds are preferably used in the range of 0.5 to 10 parts by weight with respect to 1 part by weight of the dye. Further, in the present invention,
It is also possible to add a conventionally known developer such as tetrabromobisphenol A or bis (4-hydroxyphenyl) sulfone to the low temperature color forming layer, if necessary.

Further, in the present invention, a conventionally known developer such as 3,3-dichlorophenylthiourea is used as a developer for the high temperature color forming layer.

The leuco dyes used in the present invention may be used alone or as a mixture of two or more, and as such leuco dyes,
What has been applied to this type of heat-sensitive material is arbitrarily applied, for example, triphenylmethane-based, fluoran-based, phenothiazine-based, auramine-based, spiropyran-based, indolinophthalide-based dye leuco compounds are preferably used . Specific examples of such leuco dyes include those shown below.

3,3-bis (p-dimethylaminophenyl) -phthalide, 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (also known as crystal biolettolactone), 3,3-bis (p- Dimethylaminophenyl) -6-diethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-chlorophthalide, 3,3-bis (p-dimethylaminophenyl) phthalide, 3-cyclohexylamino-6-chloro Fluoran, 3-dimethylamino-5,7-dimethylfluorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-7,8-benzfluorane, 3- Diethylamino-6-methyl-7-chlorofluorane, 3- (Np-tolyl-N-ethylamino) -6-methyl- -Anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2- {N- (3'-trifluoromethylphenyl) amino} -6-diethylaminofluorane, 2- {3,6 -Bis (diethylamino) -9- (o-chloroanilino) xanthylbenzoic acid lactam), 3-diethylamino-6-methyl-7- (m-trichloromethylanilino) fluorane, 3-diethylamino-7- (o-chloroanilino) Fluorane, 3-dibutylamino-7- (o-chloroanilino) fluorane, 3-N-methyl-N-amylamino-6-methyl-7-
Anilinofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3- (N, N-diethylamino) ) -5-Methyl-7- (N, N
-Dibenzylamino) fluorane, benzoyl leuco methylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrroispirane, 6'-bromo-3'-methoxy-benzoindolino-pyrrolispirane, 3- (2'-hydroxy) -4'-Dimethylaminophenyl) -3- (2'-methoxy-5'-chlorophenyl)
Phthalide, 3- (2'-hydroxy-4'-dimethylaminophenyl) -3- (2'-methoxy-5'-nitrophenyl)
Phthalide, 3- (2'-hydroxy-4'-diethylaminophenyl) -3- (2'-methoxy-5'-methylphenyl)
Phthalide, 3- (2'-methoxy-4'-dimethylaminophenyl) -3- (2'-hydroxy-4'-chloro-5'-
Methylphenyl) phthalide, 3-morpholino-7- (N-propyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7-trifluoromethylanilinofluorane, 3-diethylamino-5-chloro-7- (N -Benzyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7- (di-p-chlorophenyl) methylaminofluorane, 3-diethylamino-5-chloro-7- (α-phenylethylamino) fluorane, 3 -(N-ethyl-p-toluidino) -7- (α-phenylethylamino) fluorane, 3-diethylamino-7- (o-methoxycarbonylphenylamino) fluorane, 3-diethylamino-5-methyl-7- (α -Phenylethylamino) fluorane, 3-diethylamino-7-piperidi Fluoran, 2-chloro-3-(N-Mechirutoruijino)-7-(p
-N-butylanilino) fluorane, 3- (N-benzyl-N-cyclohexylamino) -5,
6-benzo-7-α-naphthylamino-4′-bromofluorane, 3-diethylamino-6-methyl-7-mesitidino-
4 ', 5'-benzofluorane and the like.

In the present invention, the combination of coloring colors can be freely selected, but the coloring of the low temperature coloring layer must be prevented during high temperature coloring. Physical properties required for such a decoloring agent are basic, poorly soluble in water,
It has a melting point of at least 80 ° C, is stable to air or heat, and has low toxicity. Examples of such a decoloring agent include the following. (A) a piperazine derivative represented by the following general formula (I), (II) or (IV), (b) a disubstituted amide compound of a divalent carboxylic acid represented by the following general formula (III), and a general formula (V) 3) in the compound represented by
A compound having one or more amide groups or having two or more amide groups and one or more tertiary amine groups.

General formula (I): General formula (II): General formula (III): General formula (IV): General formula (V) In the general formulas (I), (II), (III), (IV) and (V), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ , R ₇ , R ₈ and R ₉ ,
R ₁₀ , R ₁₁ and R ₁₃ are optionally substituted alkyl, cycloalkyl, aryl or aralkyl, and the ends of R ₅ and R ₆ and R ₇ and R ₈ are bonded to each other to form a ring. You may take the structure. R ₁₂ represents a lower alkylene group,
A represents a divalent aliphatic group or aromatic group, and X,
X and X are carbonyl or sulfonyl, Y and Y
Represents alkylene. Examples of the alkyl represented by R _{1 to} R ₁₁ and R ₁₃ include a straight chain or branched chain having 1 to 18 carbon atoms. Cycloalkyl includes cyclohexyl, aryl includes phenyl,
Examples thereof include tolyl and xylyl, and examples of the aralkyl include benzyl and phenethyl. These substituents may further have other substituents, and examples of such a substituent include, for example, alkyl, aryl, halogen and the like, as well as alkoxy, aryloxy, acyl,
Acyloxy, alkoxycarbonyl, carbamoyl,
Acylamino and the like can be mentioned. Further, in the piperazine ring in the general formulas (I), (II) and (IV),
One or more substituents such as alkyl, aryl, halogen, alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl and acylamino may be bonded.

Specific examples of the compound represented by the general formula (I) include the followings.

N-Methyl-N'-phenylacetylpiperazine N-propyl-N'-phenylacetylpiperazine, N-propyl-N'-benzoylpiperazine, N-butyl-N'-benzoylpiperazine, N-cyclohexyl-N'-benzoylpiperazine , N-hexyl-N'-benzoylpiperazine, N-lauryl-N'-benzoylpiperazine, N-stearyl-N'-benzoylpiperazine, N-phenyl-N'-benzoylpiperazine, N-benzyl-N'-benzoylpiperazine , N-phenyl-N'-cyclohexyloylpiperazine, N-phenyl-N'-acetylpiperazine, N-phenyl-N'-lauroylpiperazine, N-phenyl-N'-p-methylbenzoylpiperazine, N-phenyl- N'-p-chlorobenzoi Piperazine, N-benzoylaminoethyl-N'-benzoylpiperazine, N-benzoylaminopropyl-N'-benzoylpiperazine, N-benzoylaminobutyl-N'-benzoylpiperazine, N-benzoylaminopropyl-N'-cyclohexylpiperazine, N-cyclohexyloylaminopropyl-N'-cyclohexyloylpiperazine, N-benzoylaminoamyl-N'benzoylpiperazine, N- (p-chlorobenzoylaminoamyl) -N'-
(Chlorobenzoyl) piperazine, N-phenyl-N'-benzenesulfonylpiperazine, N-benzyl-N'-benzenesulfonylpiperazine, N-methyl-N'-benzenesulfonylpiperazine, N-propyl-N'-benzenesulfonylpiperazine, N-butyl-N'-benzenesulfonylpiperazine, N-hexyl-N'-benzenesulfonylpiperazine, N-cyclohexyl-N'-benzenesulfonylpiperazine, piperazine, N-lauryl-N'-benzenesulfonylpiperazine, N-stearyl- N'-benzenesulfonylpiperazine, N-phenyl-N'-butylsulfonylpiperazine, N-phenyl-N'-laurylsulfonylpiperazine, N-phenyl-N'-stearylsulfonylpiperazine, N-fe Le -N'- cyclohexyl sulfonyl piperazine, N- phenyl -N'- benzylsulfonyl piperazine, N- phenyl -N '- (p-methylbenzenesulfonyl) piperazine, N- butyl -N' - (p-methylbenzenesulfonyl)
Piperazine, N-benzoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N'-p-methylbenzenesulfonylpiperazine, N-benzoylaminoethyl-N'-benzenesulfonylpiperazine, N-benzoylaminobutyl- N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N'-butanesulfonylpiperazine, N-naphthoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzenesulfonylaminopropyl-N'-benzenesulfonylpiperazine, N- Butyroylaminopropyl-N'-benzoylpiperazine, N-hexyloylaminopropyl-N'-benzoylpiperazine, N-lauroylaminopropyl-N'-benzoylpiperazine , N-stearoylaminopropyl-N'-benzoylpiperazine, N-stearoylaminopropyl-N'-benzenesulfonylpiperazine and the like.

Specific examples of the compound represented by the general formula (II) include the followings.

N, N'-bis (benzenesulfonyl) piperazine, N, N'-bis (p-methylbenzenesulfonyl) piperazine, N, N'-bis (p-isopropylbenzenesulfonyl)
Piperazine, N, N'-bis (p-chlorobenzenesulfonyl) piperazine, N, N'-bis (o-chlorobenzenesulfonyl) piperazine, N, N'-bis (m-chlorobenzenesulfonyl) piperazine, N, N'-bis (P-Bromobenzenesulfonyl) piperazine, N, N'-bis (butylsulfonyl) piperazine, N, N'-bis (octylsulfonyl) piperazine, N, N'-bis (laurylsulfonyl) piperazine, N, N'- Bis (stearylsulfonyl) piperazine, N, N′-bis (cyclohexylsulfonyl) piperazine, N, N′-bis (p-laurylbenzenesulfonyl) piperazine, N, N′-bis (cyclohexylsulfonyl) piperazine, N-butylsulfonyl -N'-benzenesulfonylpiperazine, N-octylsulfonyl-N'-benzene Rufonylpiperazine, N- (o-chlorobenzenesulfonyl) -N'-benzenesulfonylpiperazine, N-lauroyl-N'-benzenesulfonylpiperazine, N-lauroyl-N '-(p-methylenesulfonyl) piperazine, N- Benzoyl-N'-benzenesulfonylpiperazine, N- (o-chlorobenzoyl) -N'-benzenesulfonylpiperazine, N- (o-methylbenzoyl) -N'-benzenesulfonylpiperazine, N, N'-bis (butyroyl) Piperazine, N, N'-bis (hexyloyl) piperazine, N, N'-bis (n-octyloyl) piperazine, N, N'-bis (tertiary octyloyl) piperazine, N, N'-bis (lauryloyl) piperazine , N, N'-bis (stearoyl) piperazine, N, N'-bis (pivalloy L) piperazine, N, N'-bis (cyclohexyloyl) piperazine, N, N'-bis (p-methylcyclohexyloyl) piperazine, N, N'-bis (p-methylphenylacetyl) piperazine, N, N'-bis (phenylacetyl) piperazine, N, N'-bis (phenylpropionyl) piperazine, N, N'-bis (benzoyl) piperazine, N, N'-bis (phenoxyacetyl) piperazine, N, N'- Bis (p-chlorobenzoyl) piperazine, N, N'-bis (2-phenoxypropionyl) piperazine, N, N'-bis (m-chlorobenzoyl) piperazine, N, N'-bis (o-chlorobenzoyl) piperazine , N, N'-bis (p-methylbenzoyl) piperazine, N, N'-bis (m-methylbenzoyl) piperazine, N, N'-bis (o-methylbenzoyl) piperine Gin, N, N'-bis (o-acetyloxybenzoyl) piperazine, N, N'-bis (o-butyryloxybenzoyl) piperazine, N, N'-bis (p-phenylbenzoyl) piperazine, N, N ' -Bis (p-methoxycarbonylbenzoyl) piperazine, N, N'-bis (p-isopropoxycarbonylbenzoyl) piperazine, N, N'-bis (p-octadecylcarbamoylbenzoyl) piperazine and the like.

In the general formula (III), R, R, R and Represents a substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, and R and R or R and Can also have their ends bonded to each other to form a ring. Examples of the alkyl generally include straight or branched ones having 4 to 18 carbon atoms, examples of the cycloalkyl include cyclohexyl, examples of the aryl include phenyl, tolyl, xylyl, and the like. Examples of alkyl include benzyl and phenethyl. These substituents can have further substituents,
Examples of such a substituent include alkyl, aryl, alkoxy, acyl, halogen and the like, as well as acylamino such as benzoylamino and acetylamino, alkoxycarbonyl, carbamoyl, aryloxy and aralkyloxy. A is an aliphatic group or an aromatic group, and when it is aliphatic, it is usually a substituted or unsubstituted alkylene having 1 to 8 carbon atoms, and when it is an aromatic group,
It is a substituted or unsubstituted arylene such as phenylene, tolylene, xylylene, etc. In this case, examples of the substituent include the above-mentioned halogen, acylamino, alkoxycarbonyl, carbamoyl, aryloxy, aralkyloxy and the like.

Specific examples of the di-substituted amide compound of the aliphatic and aromatic divalent carboxylic acids include the followings.

N, N, N ', N'-tetrabutyl succinic acid diamide, N, N, N', N'-tetraoctyl succinic acid diamide, N, N, N ', N'-tetralauryl succinic acid diamide, N, N, N ', N'-tetrastearyl succinic acid diamide, N, N, N', N'-tetraphenyl adipic acid diamide, N, N, N ', N'-tetra-p-butylphenyl adipic acid diamide, N, N, N ', N'-tetrabutyl adipic acid diamide, N, N, N', N'-tetraoctyl adipic acid diamide, N, N, N ', N'-tetralauryl adipic acid diamide, N, N, N ', N'-tetrastearyl adipic acid diamide, N, N'-dicyclohexyl-N, N'-dimethylsuccinic acid diamide, N, N'-dicyclohexyl-N, N'-dimethylglutaric acid diamide, N, N'-dicyclohexyl-N, N'-dimethyladipic acid diamide, N, N, N ', N'-tetracyclohexylazide Acid diamide, N, N'-dimethyl-N, N'-dicyclohexylsuberic acid diamide, N, N'-dimethyl-N, N'-dicyclohexyl sebacic acid diamide, N, N'-dimethyl-N, N'- Dicyclohexylmalonic acid diamide, N, N, N ′, N′-tetrabenzyladipic acid diamide, adipoyldipiperidine, adipoyldipipecoline, adipoyl-di-ε-caprolactam, adipoyldi-pyrrolidone, adipoyldipiperidone, Sebacoyl di-ε-caprolactam, cepacoyl di-piperidone, adipoyl-di-3-chloro-ε-caprolactam, succinyl-di-3-chloro-ε-caprolactam and the like.

N, N'-terephthaloylbispiperidine, N, N'-isophthaloylbispiperidine, N, N'-phthaloylbispiperidine, N, N'-terephthaloylbismorpholine, N, N'-isophthale Roylbismorpholine, N, N'-phthaloylbismorpholine, N, N'-terephthaloylbis-4-methylpiperazine, N, N'-isophthaloylbis-4-methylpiperazine, N, N'-futata Roylbis-4-methylpiperazine, N, N'-terephthaloylbis-4-phenynylpiperazine, N, N'-isophthaloylbis-4-phenylpiperazine, N, N'-phthaltaroylbis-4- Phenylpiperazine, N, N'-terephthaloylbis-4-propylpiperazine, N, N'-isophthaloylbis-4-propylpiperazine, N, N'-phthaloyl-4-propylpiperazine, N, N'- Terephthalate Irbiscaprolactam, N, N'-isophthaloylbiscaprolactam, N, N'-phthalaroylbiscaprolactam, N, N'-terephthaloylbis-3-chlorocaprolactam, N, N'-isophthaloylbis- 3-chlorocaprolactam, N, N'-phthaloylbis-3-chlorocaprolactam, N, N'-terephthaloylbisvalerolactam, N, N'-isophthaloylbis-barrellactam, N, N'-phthaloylbis Valerolactam, N, N'-terephthaloylbispyrrolidine, N, N'-isophthaloylbispyrrolidine, N, N'-phthaloylbispyrrolidine, N, N'-terephthaloylbis-diethylamine, N, N ′ -Isophthaloylbis-diethylamine, N, N′-phthaloylbis-diethylamine, N, N′-terephthaloylbis-dipropylamine, N, N′-isophthalate Ilbis-dipropylamine, N, N'-terephthaloylbis-dibutylamine, N, N'-isophthaloylbis-dibutylamine, N, N'-terephthaloylbis-cyclohexyl-methylamine, N, N ′ -Isophthaloylbiscyclohexyl-methylamine, N, N′-terephthaloylbis-dicyclohexyl-amine, N, N′-isophthaloylbis-dicyclohexyl-amine, N, N′-terephthaloylbis-diamine Benzylamine, N, N'-isophthaloylbis-dibenzylamine, N, N'-terephthaloylbis-dioctylamine, N, N'-isophthaloylbis-dioctylamine, N, N'-terephthalate Roylbis-diethoxypropylamine, N, N'-terephthaloylbis-4-chlorobutylamine, N, N'-terephthaloylbis-dibenzoylaminoethylamine N, N'-isophthaloylbis-dibenzoylaminoethylamine, N, N'-terephthaloylbis-benzoylaminopropylamine, N, N'-isophthaloylbis-benzoylaminopropylamine, N, N ′ -Terephthaloylbis-diacetylaminoethylamine, N, N′-isophthaloylbis-diacetylaminoethylamine, N, N′-terephthaloylbis (4-methylpiperidine), N, N′-terephthaloylbis (3-methylpiperidine), N, N'-terephthaloylbis (3,5-dimethylpiperidine), N, N'-terephthaloylbis (2-methylpiperidine), N, N'-terephthaloylbis (2,6-Dimethylpiperidine), N, N'-isophthaloylbis (4-methylpiperidine), N, N'-phthaloylbis (4-methylpiperidine), N, N'-isophthalo Rubis (3-methylpiperidine), N, N'-phthaloylbis (3-methylpiperidine), N, N'-isophthaloylbis (3,5-dimethylpiperidine), N, N'-phthaloylbis (3,5- Dimethylpiperidine), N, N'-isophthaloylbis (2-methylpiperidine), N, N'-phthaloylbis (2-methylpiperidine), N, N'-isophthaloylbis (2,6-dimethylpiperidine) , N, N'-phthaloylbis (2,6-dimethylpiperidine), N, N'-terephthaloylbis (4-benzylpiperidine), N, N'-isophthaloylbis (4-benzylpiperidine), N, N'-phthaloylbis (4-benzylpiperidine), N, N'-terephthaloylbis (4-methoxycarbonylpiperidine), N, N'-isophthaloylbis (4-methoxycarbonylpiperidine), N, N'- Lephthaloylbis (2-methoxycarbonylpiperidine), N, N'-isophthaloylbis (2-methoxycarbonylpiperidine), N, N'-phthaloylbis (2-methoxycarbonylpiperidine), N, N'-terephthaloylbis ( 4-ethylpiperidine), N, N'-terephthaloylbis (4-propylpiperidine), N, N'-terephthaloylbis (4-butylpiperidine), N, N'-isophthaloylbis (4- Ethylpiperidine), N, N'-isophthaloylbis (4-normalpropylpiperidine), N, N'-isophthaloylbis (4-butylpiperidine), N, N'-isophthaloylbis (4-butyl) Piperidine), N, N'-phthaloylbis (4-ethylpiperidine), N, N'-phthaloylbis (4-propylpiperidine), N, N'-phthaloylbis (4- Tilpiperidine), N, N'-terephthaloylbis (3-hydroxymethylpiperidine), N, N'-isophthaloylbis (3-hydroxymethylpiperidine), N, N'-phthaloylbis (3-hydroxymethylpiperidine) ), N, N′-terephthaloylbis (5-ethyl-2-methylpiperidine), N, N′-isophthaloylbis (5-ethyl-2-methylpiperidine), N, N′-phthaloylbis (5 -Ethyl-2-methylpiperidine), N, N'-terephthaloylbis (N-ethyl-N'-cyclohexylamine), N, N'-isophthaloylbis (N-ethyl-N'-cyclohexylamine) , N, N'-phthaloylbis (N-ethyl-N'-cyclohexylamine), N, N'-terephthaloylbis (N-propyl-N'-cyclohexylamine), N, N'-isophyl Roylbis (N-propyl-N'-cyclohexylamine), N, N'-phthaloylbis (N-propyl-N'-cyclohexylamine), N, N'-terephthaloylbis (N-butyl-N'-cyclohexylamine) ), N, N′-isophthaloylbis (N-butyl-N′-cyclohexylamine), N, N′-phthaloylbis (N-butyl-N′-cyclohexylamine), N, N′-terephthaloylbis (4-Ethyloxymethylpiperidine), N, N'-isophthaloylbis (4-ethyloxymethylpiperidine), N, N'-terephthaloylbis (4-ethyloxyethylpiperidine), N, N'- Isophthaloylbis (4-ethyloxyethylpiperidine), N, N'-terephthaloylbis (2-methoxyethylpiperidine), N, N'-isophthaloylbis (2-methoxy Tilpiperidine), N, N′-terephthaloylbis (4-methoxyethylpiperidine), N, N′-isophthaloylbis (4-methoxyethylpiperidine), N, N′-terephthaloylbis (4- Phenylpiperidine), N, N'-isophthaloylbis (4-phenylpiperidine), N, N'-phthaloylbis (4-phenylpiperidine), N, N'-terephthaloylbis (4-phenylpropylpiperidine), N, N'-isophthaloylbis (4-phenylpropylpiperidine), N, N'-phthaloylbis (4-phenylpropylpiperidine) and the like.

In the general formula (IV), R ₉ and R ₁₀ represent alkyl, cycloalkyl, aryl or aralkyl which may have a substituent. Examples of the alkyl include those having a straight or branched chain having 1 to 18 carbon atoms, examples of the cycloalkyl include cyclohexyl, examples of the aryl include phenyl, tolyl, xylyl, and the like. Examples of alkyl include benzyl and phenethyl. These substituents may further have other substituents, and examples of such substituents include alkyl, aryl, halogen, alkoxy, aryloxy, aralkyloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, Substituents such as acylamino may be mentioned. Y and Y are linear or branched carbon atoms of 1 to 18
Is an alkylene group.

Specific examples of the compound represented by the general formula (IV) include the followings.

N, N'-bis (benzoylaminoethyl) piperazine, N, N'-bis (benzoylaminopropyl) piperazine, N, N'-bis (benzoylaminobutyl) piperazine, N, N'-bis (cyclohexylaminopropyl) Piperazine, N, N'-bis (hexyloylaminopropyl) piperazine, N-benzoylaminopropyl-N'-cyclohexylaminoethylpiperazine, N-benzoylaminopropyl-N'-benzoylaminobutylpiperazine, N- (P- (Chlorobenzoylaminoamyl) -N'-benzoylaminopropylpiperazine, N-cyclohexyloylaminopropyl-N'-cyclohexyloylaminobutylpiperazine, N-naphthoylaminopropyl-N'-benzoylaminopropylpiperazine, N-butyl Royl Aminop Ropyl-N'-benzoylaminopropylpiperazine, N-lauroylaminopropyl-N'-benzoylaminopropylpiperazine, N-stearoylaminopropyl-N'-benzoylaminopropylpiperazine, N-butyroylaminopropyl-N'-cyclohexyl Ilaminobutylpiperazine, N-naphthoylaminopropyl-N′-lauroylaminopropylpiperazine, N-naphthoylaminopropyl-N′-stearoylaminopropylpiperazine and the like.

Specific examples of the compound having 3 or more amino groups in the molecule or having 2 or more amide groups and 1 or more tertiary amino groups include the followings.

N, N ', N "-tribenzoyl-diethylenetriamine, N, N', N" -tribenzoyl-dipropylenetriamine, N, N ', N ", N-tetrabenzoyl-triethylenetetramine, 1,7-dibenzoyl -4-Methyl-diethylenetriamine, 1,9-dibenzoyl-5-methyl-dipropylenetriamine, 1,7-di-α-naphthoyl-4-methyl-diethyltriamine, 1,7-di-α-naphthoyl-4- Cyclohexyl-diethylenetriamine, N, N ', N "-tripivaloyl-diethylenetriamine, N, N', N", N-tetraacetyl-triethylenetetramine, N, N ', N ", N-tetracyclohexyloyl-triethylene Tetramine, ethylenediamine tetraacetic acid tetraanilide, ethylenediamine tetraacetic acid tetracyclohexylamide, ethylenediamine tetraacetic acid tetra-2-e Tylhexylamide, ethylenediaminetetraacetic acid tetralaurylamide, ethylenediaminetetraacetic acid tetrastearylamide, ethylenediaminetetraacetic acid tetrapiperidide, ethylenediaminetetraacetic acid tetra-ε-caprolactamide and the like.

In the general formula (V), R ₁₁ and R ₁₃ represent alkyl, cycloalkyl, aryl or alkyl which may have a substituent. The alkyl usually has 1 carbon atom.
~ 18 straight chain or branched chain, cycloalkyl includes cyclohexyl, aryl includes phenyl, tolyl, xylyl, and the like, and aralkyl includes benzyl, phenethyl, and the like. To be These substituents may further have other substituents, and examples of such a substituent include, for example, alkyl, aryl, halogen, etc., as well as alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, Acylamino and the like can be mentioned. R ₁₂ represents a lower alkyl group.

Specific examples of the compound represented by the general formula (V) include the following.

1,3-bis (N-cyclohexylcarbonylpiperidyl) propane, 1,3-bis (N-benzoylpiperidyl) propane, 1,3-bis (Np-trioylpiperidyl) propane, 1,3-bis (N -Pivaloyl piperidyl) propane, 1,3-bis (N-lauroyl piperidyl) propane, polyether, polyethylene glycol derivative, solid alcohol, guanidine derivative, morpholine derivative, thiurad compound, etc. .

The decolorizing agent used in the present invention is used alone or in the form of a mixture of two or more kinds, and these are usually white and solids stable in the air, and in the case of the present invention, 80 ° C or higher, preferably Those having a melting point in the range of 120 to 250 ° C. are preferably used.

In the present invention, in order to bind and support the leuco dye, the developer and the decolorizer on a support, various conventional binders can be appropriately used, and examples thereof include polyvinyl alcohol, starch and derivatives thereof. Methoxycellulose,
Cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylic acid amide / acrylic acid ester copolymer, acrylic acid amide / acrylic acid ester / methacrylic acid terpolymer, styrene / Maleic anhydride copolymer alkali salt, isobutylene / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein, and other water-soluble polymers, polyvinyl acetate, polyurethane, styrene / butadiene copolymer Combined, polyacrylic acid, polyacrylic ester, vinyl chloride /
A latex such as vinyl acetate copolymer, polybutyl methacrylate, ethylene / vinyl acetate copolymer, styrene / butadiene / acrylic copolymer can be used.

Further, in the present invention, together with the leuco dye and the color developer, if necessary, further auxiliary additives commonly used in this type of heat-sensitive recording material, for example, a filler, a surfactant, a heat-fusible substance ( Alternatively, a lubricant) or the like can be used in combination. In this case, as the material, for example, calcium carbonate, silica,
Inorganic fine powder such as zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, talc, surface-treated calcium and silica, urea-forimarin resin, styrene / methacrylic acid copolymer, Examples thereof include organic fine powders such as polystyrene resin. Examples of the heat-fusible substance include higher fatty acids or their esters, amides or metal salts, various waxes, aromatic carboxylic acids and amines. Condensates, benzoic acid phenyl esters, higher linear glycols, 3,4-epoxy-dialkyl hexahydrophthalates, higher ketones, and other heat-fusible organic compounds having a melting point of about 50 to 200 ° C are listed. To be

After that, in order to obtain a two-color heat-sensitive recording material according to the present invention,
It can be obtained by coating and drying a liquid in which a color-forming dye, a color developer, a decoloring agent, a binder and the like are dispersed or dissolved on a support such as paper, synthetic paper and a plastic film, and repeating this. In the case of further laminating on the coated layer, it is necessary to pay sufficient attention to the solubility and the peelability of the layer so that the lower layer does not mix with the upper layer. Further, the upper layer may be applied after the coating and drying and the calender treatment. Coating weight of the hot coloring ^{layer, 0.3g / m 2 ~1.0g / m} 2, decolorizer adhesion amount of decolorizing agent layer is ^{1.0g / m 2 ~10g / m 2} , also low-temperature color-forming layer the amount of adhesion, as described above, with the leuco dye adhering as dry matter, is ^{0.2g / m 2 ~0.6g / m 2} . Adhesion amount of the case of providing the protective ^{layer, 0.5g / m 2 ~5.0g / m} 2 is preferred. If an intermediate layer provided between the color erasing agent layer and between the low-temperature color-forming layer and or decoloring layer and the high-temperature color-forming layer, the former is preferably ^{0.5g / m 2 ~5.0g / m 2} , the latter is 1 g / m ² ~ 10 g / m ² is preferred.

Further, by increasing the number of thermosensitive coloring layers in the same manner as described above, a multicolor thermosensitive recording material having three or more colors can be obtained.

〔effect〕

The multicolor thermosensitive recording material of the present invention has the above constitution, and by using the compound of the general formula (I) as a developer for the low temperature color developing layer, the color developing property and the decoloring property of the low temperature color developing layer are remarkably improved and excellent. Gives a multicolored colored image.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples. The parts and% shown below are based on weight.

Example 1 The components below were pulverized and dispersed by using a ball mill for 24 hours to obtain dispersions A to D.

[Dispersion A]

3- (N-ethyl-N-amylamino) -6-methyl-
7-anilinofluorane (black) 20 parts Polyvinyl alcohol 10% aqueous solution 20 parts Water 60 parts [Dispersion B] Ethyl bis (3-bromo-4-hydroxyphenyl) acetate 10 parts Calcium carbonate 10 parts Polyvinyl alcohol 10% aqueous solution 20 parts Water 60 parts [Dispersion C] 3-Diethylamino-7-chlorofluorane (red) 20
Parts polyvinyl alcohol 10% aqueous solution 20 parts water 60 parts [dispersion D] 3,3-dichlorophenylthiourea 10 parts calcium carbonate 10 parts polyvinyl alcohol 10% aqueous solution 20 parts water 60 parts Dispersion A obtained as described above The dispersion B was mixed and stirred to obtain a thermosensitive color forming layer forming liquid for low temperature color development. On the other hand, Dispersion C and Dispersion D were mixed and stirred to obtain a thermosensitive coloring layer forming liquid for high temperature color development. Further, an erasing agent layer forming liquid for forming an erasing agent layer was prepared in the following ratio.

[Decolorant forming liquid]

N, N, N ', N'-Tetrabutylsuccinamide 20 parts Polyvinyl alcohol aqueous solution 20 parts Water 60 parts Next, on a high quality paper weighing about 52 g / m ² , the high temperature thermosensitive coloring layer forming liquid (dry) Coating amount 6g / m ² ), decolorant layer forming liquid (drying amount 4g / m ² ) Low temperature thermosensitive coloring layer forming liquid (drying amount 4g / m ² ) are applied sequentially and dried to obtain multicolor heat A recording material was obtained.

Example 2 As Example 1, except that benzyl bis (3-chloro-4-hydroxyphenyl) acetate was used in place of the ethyl bis (3-bromo-4-hydroxyphenyl) acetate of the liquid B. A heat sensitive recording material was obtained in the same manner.

Example 3 Thermal recording was carried out in the same manner as in Example 1 except that methyl bis (4-hydroxyphenyl) acetate was used in place of ethyl bis (3-bromo-4-hydroxyphenyl) acetate of the liquid B in Example 1. Got the material.

Example 4 The same as Example 1 except that phenyl bis (3-chloro-4-hydroxyphenyl) acetate was used in place of the ethyl bis (3-bromo-4-hydroxyphenyl) acetate of the liquid B in Example 1. A heat sensitive recording material was obtained in the same manner.

Comparative Example 1 In Example 1, a heat-sensitive recording material was obtained by using bis (4-hydroxyphenyl) sulfone instead of ethyl bis (3-bromo-4-hydroxyphenyl) acetate of the B liquid.

Comparative Example 2 A thermosensitive recording material was obtained by using benzyl p-hydroxybenzoate in place of the ethyl bis (3-bromo-4-hydroxyphenyl) acetate of the liquid B in Example 1.

The multicolor thermosensitive recording materials of Examples and Comparative Examples obtained as described above were tested as follows.

Image density: Matsushita Electronics Co., Ltd., printing tester with thin film head, head power 0.6 W / dot, 1 line recording time 10 ms /
, The scanning line density was 8 x 7.7 dots / mm, the low-temperature coloring layer printed with a pulse width of 1.0 ms, and the high-temperature coloring layer printed with 2.2 ms, and the printing density was determined by the Macbeth densitometer RD-514 (filter wratten-10
Measured in 6).

Residual rate The residual rate of low-temperature color development during high-temperature color development, It is expressed by the formula.

The results are shown in the table.

As described above, it is understood that the multicolor heat-sensitive recording material of the present invention is excellent in the color developability of the low temperature color developing layer and has the remarkably improved decoloring property.

Claims (1)

[Claims] 1. A multicolor thermosensitive recording material comprising a support, on which a high-temperature color-developing layer, a decoloring layer and a low-temperature color-developing layer are laminated in this order, and a compound having a structure represented by the following general formula as a developer for the low-temperature color-developing layer. A multicolor heat-sensitive recording material comprising: (In the formula, X: halogen or hydrogen R: alkyl group or aryl group)