JPS62234986A - Two-color thermal recording material - Google Patents

Abstract

PURPOSE:To obtain not only a blackish low temp. developed color image but also a sharp high temp. developed color image free color mixture, by using a specific bisphenol derivative as the coupler of the low temp. color forming layer in a two-color thermal recording material. CONSTITUTION:In a two-color thermal recording material wherein a high temp. color forming layer, an erasing layer and a low temp. color forming layer are laminated to a support in this order, a bisphenol derivative represented by general formula (A) wherein Z is -S- and R1, R2, R3 and R4 are H or 1-4C alkyl) is used as the coupler of the low temp. color forming layer and, if necessary, an intermediate layer based on a heat-meltable substance with m.p. 110-140 deg.C is provided between the low temp. color forming layer and the erasing layer. By this method, a sharp two-color image showing a excellent color forming property, easily erased by an erasing agent and imparting a low temp. developed color image stable with the elapse of time can be obtained.

Description

[Detailed description of the invention] “I n11/71!ffi ta
h, ie 0 [Technical Field] The present invention relates to a two-color heat-sensitive recording material, and more specifically, it mainly comprises a normally colorless or slightly pale leuco dye and a color developer that reacts with the leuco dye when heated to develop a color. The present invention relates to a two-color heat-sensitive recording material formed by laminating heat-sensitive coloring layers containing the above-mentioned components.

[Prior art]

A thermosensitive recording material is a material in which a thermosensitive coloring layer capable of forming a colored 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.

These conventional heat-sensitive recording materials include a colorless or light-colored leuco dye (color-forming main agent) having rough 1-rings, lactam rings, spiropyran rings, etc. in the heat-sensitive coloring layer, and coloring occurs when the leuco dye reacts with this leuco dye when heated. Those containing a color developer (color development aid) are widely used because they have clear color tones and cause less fogging.

By the way, heat-sensitive recording materials can easily produce colored images just by heating them, so they are not only used for copying books, documents, etc., but are also used in various fields such as computer, facsimile, telex, and other fields for recording various types of information and measuring equipment. However, depending on the purpose of recording, in order to display particularly necessary data and numbers more clearly, the coloring of that part (
It goes without saying that it is desirable to be able to record with the display color (displayed color) different from the developed color of other parts.

Recently, attempts have been made to obtain multicolor recording by utilizing differences in heating temperature or thermal energy, and various multicolor thermosensitive recording papers have been proposed accordingly. Multi-color thermosensitive recording paper is generally formed by stacking two types of high-temperature and low-temperature coloring layers that develop different tones with different coloring heat energies on a support, and can be broadly classified into the following two types: Divided into types. One is to mix the color with the color tone of the low temperature coloring layer when coloring the high temperature coloring layer to obtain a color tone different from the coloring tone of the low temperature coloring layer, and the other is to color the high temperature coloring layer. In this case, by using a decoloring agent that decolorizes the low-temperature color-forming layer, only the color tone of the high-temperature color-forming layer is obtained without color mixture of the color tone of the low-temperature color-forming layer. As specific examples of these, the former is disclosed in Japanese Patent Publication No. 49-69, Japanese Patent Publication No. 4342-1972, Publication No. 27708-1977,
JP-A-48-86543, JP-A-49-6523
9, etc., and the latter was published in the Special Publication No. 1973.
-17865 Publication, Special Publication No. 50-17866,
Special Publication No. 51-29024, Special Publication No. 51-8754
Publication No. 2, Japanese Unexamined Patent Application Publication No. 18048/1983, Japanese Patent Publication No. 1983
-36519, etc., respectively.

However, in the case of the former multicolor thermosensitive recording paper,
When coloring at a high temperature, the color tones that can be concretely achieved in order to mix the color with the color tone of the low temperature coloring layer are limited to black threads where the high temperature coloring tone is strong, such as red-black, blue-black, etc. There is. On the other hand, in the case of the latter multicolor thermosensitive recording paper, the combination of color tones can be freely selected, but when coloring at high temperatures, high aliphatic alcohols, polyethers, polyethylene glycol derivatives,
Acetamide, stearamide, phthaloni-1-lyl as nitrogen-containing organic compounds, guanidine derivatives, morpholine derivatives, etc. as amine derivatives are used. However, with such multicolor recording materials, when heated, the density of the low-temperature color image area decreases due to the influence of the decoloring agent, making it impossible to obtain high density, and the low-temperature color image area also fades over time. There was a problem.

Furthermore, in order to prevent the influence of the decoloring agent on the low-temperature coloring layer, proposals have been made to provide an intermediate layer containing a film-forming polymeric binder as a main component between the decolorizing layer and the low-temperature coloring layer. ,
Providing an intermediate layer can prevent color fading (preservability) of low-temperature colored images over time, but it may prevent the low-temperature coloring layer and the decoloring layer from dissolving (decoloring) when the high-temperature coloring layer is coloring, and may cause color mixing. This results in a high-temperature colored image.

Phenol derivatives, P-benzylbenzoic acid ester derivatives, thiourea derivatives, etc. have been proposed as color developers for the low-temperature coloring layer of two-color thermosensitive recording materials. There was no material that satisfied all of the requirements such as color separation (color separation) and stability over time.

For example, P-
Products using benzyl benzoic acid ester derivatives have good color development in the low-temperature layer, but they have the drawbacks of being difficult to erase and causing large image fading. The thiourea derivatives found in publications have good coloring properties and good decoloring properties, but they have drawbacks such as recoloring of the discolored areas over time and poor stability, and none of them has satisfied all of the above requirements.

〔the purpose〕

An object of the present invention is to provide a two-color thermosensitive recording material that is capable of obtaining blackish low-temperature colored images and clear high-temperature coloring without color mixture, and in which the colored images do not fade over time. .

〔composition〕

According to the present invention, in a two-color thermosensitive recording material in which a high-temperature coloring layer, a decoloring layer, and a low-temperature coloring layer are laminated in that order on a support, the color developer of the low-temperature coloring layer is represented by the following general formula (A). The bisphenol derivative shown above was used, and if necessary, an intermediate layer mainly composed of a thermofusible substance with a melting point of +10°C to 140°C was provided between the low-temperature coloring layer and the decoloring layer. A two-color heat-sensitive recording material is provided.

General formula: R4 represents +1 or a C1-C4 alkyl group. ) Since the two-color heat-sensitive recording material of the present invention uses the bisphenol derivative represented by the general formula (1) in the low-temperature coloring layer, it exhibits excellent coloring properties and is easily erased with a coloring agent. It is possible to obtain a clear two-color image that is stable at low temperature even over time.

In addition, in this case, there is a melting point of 110% between the decoloring layer and the low-temperature coloring layer.
By providing an intermediate layer mainly composed of a thermofusible substance at a temperature of 140°C to 140°C, it is possible to prevent a low-humidity colored image from fading due to the eutectic phenomenon, and to obtain a two-color image with excellent color separation. I can do it.

Examples of the phenolic substance represented by the general formula (1) used in the present invention include the following.

Further, as the thermofusible substance for the intermediate layer provided between the low-temperature coloring layer and the decoloring layer, a compound having a melting point of 110 to 1/10°C, such as N-octadecyl-carbamoyl-P-methoxycarbonylbenzene, is used. , P-benzyloxybenzoate, benzyl-xylene bisstearamide, N
, N'-distearyl isophthalic acid amide, zinc stearate, aluminum stearate, magnesium stearate, etc. are used.

This intermediate layer may also contain a film-forming polymer binder, filler, and the like. In this case, the melting point of the thermofusible substance is 11
If the temperature is less than 0℃, the eutectic phenomenon will progress too much and the effect will not be sufficient, and if the temperature exceeds 140℃, the decoloring layer will become a low-temperature coloring R.
This is not preferable because it prevents the two-minute separation from becoming compatibilized.

In the present invention, the color developer contained in the high-temperature coloring layer includes 1, for example, N,N'-diphenylthiourea, N-p
-ethylphenyl-N'-phenylthiourea, N-P-
Butylphenyl-N'-phenylthiourea, N, N'
-di-m-chlorophenylthiourea.

N,N'-di-P-talolophenylthiourea, N,
N'-di-m-trifluoromethylphenylthiourea.

N,N'-di-n1-methylphenylthiourea, /
1,4'-isopropylidene diphenol, II, 4'
-isopropylidene bis(2-fluorophenol),
4,4'-isopropylidene bis(2,6-dibromophenol), 4,4'-isopropylidene bis(2,
6-dichlorophenol), 4,4'-isopropylidene bis(2-methylphenol), 4,4'-isopropylidene bis(2-t, crt;-butylphenol), 4,4'-5ee-butylidene diphenol , 4,4'-cyclohexylidenebis(2-methylphenol), II-tart, -butylphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, 3,5 -xylenol, thymol, methyl-4-hydroxybenzoate, 4-hydroxyace1hephenone, novolac type phenolic resin, 2,2'-thiobis(4,6-dichlorophenol), catechol, resorcin, hydroquinone, pyroganol, phloroglucin, fluoro Glycinecarboxylic acid, II-jcrt-octylcatechol, 2,2'-methylenebis(4-fluorophenol)
, 2,2'-methylenebis(4-methyl-6-jer
L, -butylphenol), 2,2'-dihydroxydiphenyl, ethyl ρ-hydroxybenzoate, P-hydroxybenzoate, propyl hexaate, butyl P-hydroxybenzoate, p-ethylbenzyl benzoate, P- p-chlorobenzyl hydroxybenzoate, m-o-chlorobenzyl P-hydroxybenzoate, P-methylbenzyl P-hydroxybenzoate, n-n P-hydroxybenzoate
-octylbenzoic acid, zinc salicylate, 1-hydroxy-2-naphthoic acid, 2-hydroxy-6-naphthoic acid,
Zinc 2-hydroxy-6-naphthoate, 4-hydroxydiphenylsulfone, 4-hydroxy-4'-chlorodiphenylsulfone, bis(4-hydroxyphenyl)sulfide, etc. are used, as well as guanidine-based organic compounds as shown below. Basic color developers may also be used.

(4)■-NH-hired-NH-〇(5)■-NH-rental-NH-〇(6) (E>-N)I-rental-NH-■(7)■-NH
-NH-(E>■-“-■NH-C-NH The leuco dyes used in the present invention can be used alone or in combination of two or more types, and such leuco dyes include:
Those applied to this type of heat-sensitive material can be arbitrarily applied. For example, leuco compounds of dyes such as triphenylmethane-based, fluoran-based, phenothiazine-based, auramine-based, spiropyran-based, and indolinophthalide-based dyes 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 violet lactone), 3.3-bis(p- dimethylaminophenyl)-6-dimethylaminophenyl, 3.3-bis(P-dimethylaminophenyl)-6-chlorophthalide, 3.3-bis(ρ-dibutylaminophenyl)phthalide.

3-Cyclohexylamino-6-chlorofluorane.

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-(N-p-tolyl-N-ethylamino)-6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane.

2-(N-(3'-trifluoromethylphenyl)amino)-6-dinithylaminofluorane.

2-(3,6-bis(diethylamino)-9-(o-
Chloranilino)xantylbenzoic acid lactam).

3-diethylamino-6-methyl-7-(m-trichloromethylanilino)fluoran.

3-diethylamino-7-(0-chloroanilino)fluoran, 3-dibutylamino-7-(o-chloroanilino)fluoran, 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)fluoran.

Benzoylleucomethylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrylospirane.

6'-Bromo-3'-methoxy-benzoindolino-pyrylospirane, 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)fluoran, 3-pyrrolidino-7-(di-ρ-chlorophenyl)methylaminofluorane, 3-diethylamino-5-chloro-7-(α-phenylethylamino)fluoran, 3 -(N-ethyl-p-toluidino)-7-(α-phenylethylamino)fluoran, 3-diethylamino-7-(0-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7-(α -phenylethylamino)fluoran, 3-diethylamino-7-piperidinofluorane.

2-chloro-3-(N-methyltoluidino)-7-(p
-〇-butylanilino)fluorane, 3-(N-benzyl-N-cyclohexylamino)-5
, 6-penzo 7-α-naphthylamino-4'-bromofluorane, 3-diethylamino-6-methyl-7-mesitidino 4
',5'-benzofluorane etc.

In the present invention, specific examples of particularly preferable leuco dyes to be contained in the high temperature coloring layer include 3-diethylamino-7-chlorofluoran, 3-diethylamino-6-methyl-7-chlorofluoran, and 3-cyclofluoran. Examples include hexylamino-6-chlorofluorane, 3-diethylaminobenzo[α]fluorane, and the like. Furthermore, in the high-temperature color forming layer, acylated lactone or sultone type acid leuco dyes as shown below can also be used in combination with the above-mentioned guanidine color developer.

In the present invention, the combination of color tones can be freely selected, but it is necessary to prevent the low-temperature coloring layer from coloring during high-temperature coloring. Material properties required for such a color erasing agent include: showing basicity, being sparingly soluble in water, having a melting point of at least 80°C, and being stable in air or against heat. These include low toxicity and low toxicity. Examples of such decolorizing agents include the following.

(a) Piperazine derivatives represented by the following general formula (+), (II) or (IV), (b) the following general formula (III)
A disubstituted amide compound of a dihydric carboxylic acid represented by (c) having 3 or more amide groups in the molecule, or 2
A compound having one or more amide groups and one or more tertiary amine groups. General formula (■) 2 General formula (■) 2 General formula (■) 2 General formula (■): General formula (1), (11), (III) and (IV
) middle, R engineering, R2, R3, R4, R5, II6. R7,
Rδ, R3 and RIO are alkyl, cycloalkyl, aryl or aralkyl which may have a substituent, and the terminals of R5 and R6 and R7 and R8 may be bonded to each other to form a cyclic structure. Further, A represents a divalent aliphatic group or an aromatic group, x, x□ and x2 are carbonyl or sulfonyl, and Yl and Yl represent alkylene. The alkyl represented by R□ to RIO usually includes a straight chain or branched chain having 1 to 18 carbon atoms, the cycloalkyl includes cyclohexyl, and the aryl includes phenyl, 1 to 18 carbon atoms, and cycloalkyl includes cyclohexyl. Examples of aralkyl include benzyl and phenethyl. These substituents may further have other substituents, such as alkyl, aryl, halogen, alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, Examples include acylamino. Further, the piperazine ring in general formulas (I) to (II) and (TV) also includes alkyl, aryl, halogen, alkoxy, aryloxy, acyl, and acyloxy.

One or more substituents such as alkoxycarbonyl, carbamoyl, and acylamino may be bonded.

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

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-chlorobenzoylpiperazine, N-benzoylaminoethyl-N'-benzoylpiperazine, N-benzoylaminopropyl-N'-benzoylpiperazine, N-benzoylaminobutyl- N'-benzoylpiperazine, N-benzoylaminopropyl-N'-cyclohexylpiperazine.

N-cyclohexylaminopropyl-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-phenyl-N'-cyclohexylsulfonylpiperazine.

N-phenyl-N'-benzylsulfonylpiperazine, N-phenyl-N'-(ρ-methylbenzenesulfonyl)piperazine.

N-butyl-N'-(p-methylbenzenesulfonyl)piperazine, N-benzoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N'-ρ-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, etc.

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

N,N'-bis(benzenesulfonyl)piperazine.

N,N'-his(P-methylbenzenesulfonyl)piperazine, N,N'-bis(p-isopropylbenzenesulfonyl)piperazine, N,N'-bis(p-chlorobenzenesulfonyl)piperazine, N,N'-bis (0-chlorobenzenesulfonyl)piperazine, N,N'-bis(IIl-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'-benzenesulfonylpiperazine, N-(o-chlorobenzenesulfonyl)-~ '-benzenesulfonylpiperazine, N-lauroyl-N'-benzenesulfonylpiperazine, N-lauroyl-N'-(p-methylbenzenesulfonyl)piperazine, N-benzoyl-N'-benzenesulfonylpiperazine, N-(o-chloro benzoyl)-N'-benzenesulfonylpiperazine, N-(o-methylbenzoyl)-N'-benzenesulfonylpiperazine, N,N'-bis(butyroyl)piperazine, N,N'
-bis(hexyloyl)piperazine, N,N'-bis(n-ofthyroyl)piperazine, N,N'-bis(tertiary-ofthyroyl)piperazine, N,N'-bis(lauriloyl)piperazine.

N,N'-bis(stearoyl)piperazine, N,N
'-bis(pivaloyl)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)piperandine, N,N
'-bis(phenoxyacetyl)piperazine, N,N
'-bis(p-chlorobenzoyl)piperazine, N,
N'-bis(2-phenoxypropionyl)piperazine, N,N'-bis(1-chlorobenzoyl)piperazine, N,N'-bis(0-chlorobenzoyl)piperazine.

N,N'-bis(p-methylbenzoyl)piperazine.

N,N'-bis(m-methylbenzoyl)piperazine, N,N'-bis(0-methylbenzoyl)piperazine, N,N'-bis(0-acetyloxybenzoyl)
Piperazine, N,N'-bis(0-butyryloxybenzoyl)piperazine, N,N'-bis(p-7enylbenzoyl)piperazine, N,N'-bis(ρ-methoxycarbonylbenzoyl)piperazine, N,N '-bis(p-isopropoxycarbonylbenzoyl)piperazine.

N,N'-bis(p-octadecylcarbamoylbenzoyl)piperazine and the like.

In the general formula (III), R5, R6, I'+7 and R811 represent substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, and R5 and R6 or R
7 and R8 can also be bonded at their respective ends to form a ring. The alkyl usually has 4 carbon atoms.
~18 straight or branched chains, examples of cycloalkyl include cyclohexyl, examples of aryl include phenyl, tolyl, xylyl, etc., and examples of aralkyl include benzyl, phenethyl, etc. It will be done. These substituents may further have other substituents, such as alkyl, aryl, alkoxy, acyl, halogen, etc.
Acylamino such as benzoylamino and acetylamino,
Examples include alkoxycarbonyl, carbamoyl, aryloxy, aralkyloxy and the like. A is an aliphatic group or an aromatic group; in the case of an aliphatic group, it is usually substituted or unsubstituted alkylene having 1 to 8 carbon atoms; in the case of an aromatic group, it is substituted or unsubstituted phenylene, tolylene,
It is arylene such as xylylene, and in this case, examples of the substituent include the above-mentioned halogen, acylamino, alkoxycarbonyl, carbamoyl, aryloxy, aralkyloxy, and the like.

Specific examples of the disubstituted amide compounds of aliphatic and aromatic dihydric carboxylic acids include the following.

N,N,N',N'-tetrabutylsuccinic diamide, N,N,N',N'-tetraoctylsuccinic diamide.

N,N,N',N'-tetralaurylsuccinic diamide, N,N,N',N'-tetrastearylsuccinic diamide.

N,N,N',N'-tetraphenyladipic acid diamide.

N,N,N',N'-tetra-ρ-butylphenyladipate diamide, N,N,N',N'-tetrabutyladipate diamide, N,N,N',N'-tetraoctyladipate diamide, N,N,N',N'-tetraoctyladipate diamide, N,N,N',N'-tetrastearyladipate diamide.

N,N'-dicyclohexyl-N,N'-dimethylsuccinic acid diamide, N,N'-dicyclohexyl-N,N'-dimethylglutaric acid diamide, N,N'-dicyclohexyl-N,N '-dimethyladipate diamide, N,N,N',N'-tetracyclohexyladipate diamide, N,N'-dimethyl-N,N'-dicyclohexylsperate diamide, N,N'-dimethyl-N , N'-dicyclohexylsebacic acid diamide, N,N'-dimethyl-N,N'-dicyclohexylmalonic acid diamide, N,N,N',N'-tetrabenzyl adipic acid diamide, adiboyldipiperidine, adiboyl dibipecoline, adipoyldi-ε-caprolactam, adipoyldi-
Pyrrolidone.

adiboyldipiperidone, Sebacoil di-ε-caprolactam, Sebacoil di-piperidone, Adipoyl-di-3-chloro-ε-caprolactam, Succinyl-di-3-chloro-ε-caprolactam, etc.

N,N'-terephthaloyl bispiperidine, N,N'
-Isophthaloyl bispiperidine.

N,N'-phthaloyl bispiperidine, N,N'-
Terephthaloylbismorpholine, N,N'-isophthaloylbismorpholine, N,N'-phthaloylbismorpholine, N,N'-terephthaloylbis-4-methylpiperazine, N,N'-isophthaloyl rubis-4-methylpiperazine, N,N'-phthaloylbis-4-methylpiperazine.

N,N'-terephthaloylbis-4-phenylpiperazine, N,N'-isophthaloylbis-4-phenylpiperazine, N,N'-phthaloylbis-4-phenylpiperazine, N,N'-terephthaloy Rubis-4-propylpiperazine, N,N'-isophthaloylbis-4-propylpiperazine, N,N'-phthaloyl-4-propylpiperazine, N
, N'-terephthaloyl biscaprolactam, N, N
'-Isophthaloyl biscaprolactam, N, N'
-phthaloylbiscaprolactam, N,N'-terephthaloylbis-3-chlorocaprolactam, N,N'-isophthaloylbis-3-chlorocaprolactam.

N,N'-phthaloylbis-3-chlorocaprolactam, N,N'-terephthalolbisvalerolactam, N,N
'-Isophthaloyl bisvaleractam, N, N'
-phthaloylbiscaprolactam, 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'-Isophthaloylbis-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-dibenzylamine, N,N'-Isophthaloylbis-dibenzylamine, N,N'-Terephthaloylbis-dioctylamine, N,N'-Isophthaloyl Loylbis-dioctylamine, N,N'-terephthaloylbisulfetoxypropylamine.

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'-terephthaloyl bis(3-methylpiperidine), N,N'-terephthaloyl bis(3,5-dimethylpiperidine), N,N'-terephthaloyl bis(2-methylpiperidine), N,N'-terephthaloylbis(2,6-dimethylpiperidine), N,N'-isophthaloylbis(4-methylpiperidine), N,N'-phthaloylbis(4-methylpiperidine)
, N,N'-isophthaloylbis(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'-terephthaloyl bis(4-methoxycarbonylpiperidine), N,N'-isophthaloyl bis(4-methoxycarbonylpiperidine), N,N'-terephthaloyl bis(2-methoxycarbonylpiperidine) .

N,N'-Isophthaloylbis(2-methoxycarbonylpiperidine).

N,N'-phthaloylbis(2-methoxycarbonylpiperidine), N,N'-terephthaloylbis(4-ethylpiperidine), N,N'-terephthaloylbis(4-propylpiperidine), N,N' -terephthaloyl bis(4-butylpiperidine), N,N'-isophthaloyl bis(4-ethylpiperidine), N,N'-isophthaloyl bis(4-n-propyl biveridine), N,N '-Isophthaloylbis(4-butylpiperidine), N,N'-isophthaloylbis(4-butylpiperidine), N,N'-phthaloylbis(4-ethylpiperidine)
, N,N'-phthaloylbis(4-propylpiperidine), N,N'-phthaloylbis(4-butylpiperidine)
.

N,N'-terephthaloyl bis(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'-isophthaloylbis(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'- Terephthaloyl bis(2-methoxyethylpiperidine), N,N'-isophthaloylbis(2-methoxyethylpiperidine), N,N'-terephthaloylbis(4-methoxyethylpiperidine), N,N' -(isophthaloyl bis(4-methoxyethylpiperidine), N,N'-terephthaloyl bis(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), R9 and R10 represent alkyl, cycloalkyl, aryl or aralkyl which may have a substituent, and the alkyl is usually
Examples include linear or branched chains having 1 to 18 carbon atoms, cycloalkyl includes cyclohexyl, aryl includes phenyl, tolyl, xylyl, etc., and aralkyl includes benzyl, phenethyl, etc. etc. These substituents can further have other substituents, such as alkyl, aryl, halogen, alkoxy, aryloxy, aralkyloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, Examples include substituents such as acylamino. Y and Y2 are linear or branched alkylene groups having 1 to 18 carbon atoms.

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

N,N'-bis(benzoylaminoethyl)piperazine, N,N'-bis(benzoylaminopropyl)piperazine, N,N'-bis(benzoylaminobutyl)piperazine, N,N'-bis(cyclohexylamino N,N'-bis(hexyloylaminopropyl)piperazine, N-benzoylaminopropyl-N'-cyclohexylaminoethylpiperazine.

N-benzoylaminopropyl-N'-benzoylaminobutylpiperazine, N-(P-chlorobenzoylaminoamyl)-N'-benzoylaminopropylpiperazine.

N-cyclohexylaminopropyl-N'-cyclohexylaminobutylpiperazine, N-naphthoylaminopropyl-N'-benzoylaminopropylpiperazine, N-butyroylaminopropyl-N'-benzoylaminopropylpiperazine, N-lauroylaminopropyl-N'-benzoylaminopropylpiperazine.

N-stearoylaminopropyl-N'-benzoylaminopropylpiperazine, N-butyroylaminopropyl-N'-cyclohexylaminobutylpiperazine, N-naphthoylaminopropyl-N'-lauroylaminopropylpiperazine, N-naphtho ylaminopropyl-N'-stearoylaminopropylpiperazine, etc.

Further, specific examples of the compound having three or more amino groups in the molecule, or having two or more amide groups and one or more tertiary amino groups include, for example, the following.

N, N', N''-tribenzoyl-diethylenetriamine, N, N', N'-tribenzoyl-dipropylene triamine, N, N', N', N#'-tetrabenzoyl-triethylenetetramine, ■, 7 -dibencyyl-4-methyl-diethylene 1-triamine, 1,9-dibenzoyl-5-methyl-dipropylenetriamine, 1,7-di-α-naphthoyl-4-methyl-diethyltriamine.

1.7-diα-def-1-yl-4-cyclohexyl-
Diethylenetriamine, N,N',N'-tripivaloyl-diethylenetriamine.

N, N', N', N""-tetraacetyl-triethylenetetramine, N, N', N", N"'-tetracyclohexyloyl-1-lyethylenetetramine, ethylenediaminetetraacetic acid tetraanilide, ethylenediaminetetraacetic acid tetracyclo Hexylamide, ethylenediaminetetraacetic acid tetra-2-ethylhexylamide.

Ethylenediaminetetraacetic acid tetralaurylamide, ethylenediaminetetraacetic acid tetrastearylamide, ethylenediaminetetraacetic acid tetrapiperidide, ethylenediaminetetraacetic acid tetra-ε-cabrolactamide, and the like.

Other examples include polyethers, polyethylene glycol derivatives, solid alcohols, guanidine derivatives, morbuolin derivatives, thiurado compounds, and the like.

The decolorizing agent used in the present invention may be used alone or in the form of a mixture of two or more, and these are usually white solids that are stable in the air. 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, color developer, and decolorizer on the support, various conventional binders can be used as appropriate, such as polyvinyl alcohol, starch and its derivatives, methoxycellulose,
Cellulose derivatives such as hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylamide/acrylic acid ester copolymer, acrylamide/acrylic acid ester/methacrylic acid ternary copolymer, styrene / Maleic anhydride copolymer alkali salt, imbutylene / Maleic anhydride copolymer alkaline salt, polyacrylamide, sodium alginate, gelatin, casein, and other water-soluble polymers, as well as polyvinyl acetate, polyurethane, styrene/butadiene, etc. Latexes such as polymers, polyacrylic acid, polyacrylic esters, vinyl chloride/vinyl acetate copolymers, polybutyl methacrylate, ethylene/vinyl acetate copolymers, styrene/butadiene/acrylic copolymers can be used. .

In addition, in the present invention, in addition to the leuco dye and color developer, if necessary, auxiliary additive components commonly used in this type of heat-sensitive recording material, such as fillers, surfactants, thermofusible substances ( or lubricant), etc. can be used in combination. In this case, as a filler.

For example, calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate,
In addition to inorganic fine powders such as clay, talc, and surface-treated calcium and silica, organic fine powders such as urea-polymarin resin, styrene/methacrylic acid copolymer, and polystyrene resin can be mentioned. As a fusible substance,
For example, in addition to higher fatty acids or their esters, amides, or metal salts, various waxes, condensates of aromatic carboxylic acids and amines, benzoic acid phenyl esters, higher linear glycols, 3,4-epoxy-hexahydrophthal Examples include dialkyl acids, higher ketones, and other thermofusible organic compounds having a melting point of about 50 to 200°C.

Furthermore, if necessary, an intermediate layer mainly composed of a thermofusible substance or resin may be provided between the high temperature coloring layer and the decoloring layer in order to improve the stability of the high temperature coloring layer over time. Further, a retaining layer may be provided on the low-temperature coloring layer in order to improve matching properties with the thermal head (head dregs, sticking, etc.).

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples. Note that all parts and percentages shown below are based on weight.

Example 1.2 Each of the following ingredients was prepared using a sand mill to give an average particle size of 2 to 2.
The particles were pulverized and dispersed to a particle size of 3 μm to prepare dispersions A to F.

[Dispersion liquid-A]

3-(N-ethyl-N-amylamino)-6-methyl-
7-anirithufluoran (black) 20 parts 10% hydroxyethyl cellulose aqueous solution 2011 water
60〃[Dispersion-B] 4.4'-thiobis(3-methyl-6-t-to-dibutylphenol calcium carbonate) 10〃Polyvinyl alcohol (10% aqueous solution) 20# water
6
0 [Dispersion-C] N-octadecyl-carbamoyl-P-carbonylbenzene (melting point 118-122°C) 20 parts methylcellulose 5% aqueous solution 40 parts water
40 parts [Dispersion-D] N,N'-isophthaloyldi(N-methyl-N=cyclohexylamine) 20 parts 10% polyvinyl alcohol aqueous solution 20 parts water
6
0 parts [Dispersion-F] 3-diethylamino-7-chlorofluoran (red) 2
0 parts 10% hydroxyethyl cellulose aqueous solution 20 water

601! [Dispersion-F] Bisphenol A 10 parts Calcium carbonate 10J110%
Hydroxyethyl cellulose 15n water
651
10 parts of dispersion A prepared as above, 87 parts of dispersion
0 parts and 20 parts of water were mixed and stirred to obtain a thermosensitive color forming liquid for low temperature. On the other hand, dispersion EIO part, dispersion E
70 parts and 20 parts of water were respectively mixed and stirred to obtain a thermosensitive coloring layer forming liquid for high temperature coloring.

Next, on top of a commercially available high-quality paper with a basis weight of about 52 g/rrr, the high-temperature color forming layer forming liquid was applied and dried so that the amount of drying was 5.0 g/rd to form a high-temperature color forming layer. P L
, -* rυ 4th floor n (Zaibatsu Tsuzuri Punishment Tracing) or Elbow Control is 3.0g/n? A decoloring layer is formed by coating and drying, and then the low temperature coloring layer forming liquid is applied on top of the decoloring layer until the drying amount is 3.5.
The two-color heat-sensitive recording material of Example 1 was obtained by coating and drying to form a low-temperature coloring layer. Further, an intermediate layer of Ig/rrr was formed between the decoloring layer and the low-temperature coloring layer using Dispersion C to obtain the two-color thermosensitive recording material of Example 2.

Example 3 Zinc stearate (M
A two-color heat-sensitive recording material of the present invention was obtained in the same manner as in Example 1, except that P (118°C) was used for the intermediate layer.

Example 4 4゜4' used in the low temperature thermosensitive coloring layer forming liquid of Example 2
-thiobis(3-methyl-6-t-butylphenol)
A two-color heat-sensitive recording material of the present invention was obtained in the same manner as in Example 1, except that 4,4'-cyclohexylidene diphenol was used.

Comparative Example 1 4゜4' used in the low temperature thermosensitive color forming layer forming liquid of Example 1
-thiobis(3-methyl-6-butylphenol)
A comparative two-color thermosensitive recording material was obtained in the same manner as in Example 1, except that 3,3-dichlorophenylthiourea was used instead of 3,3-dichlorophenylthiourea.

Comparative Example 2 4゜4' used in the low temperature thermosensitive coloring layer forming liquid of Example 1
A comparative two-color thermosensitive recording material was obtained in the same manner as in Example 1, except that -thiobis(3-methyl-Gt, -butylphenol) was replaced with benzyl P-oxybenzoate.

Comparative Example 3 Comparative Example 2 was prepared in the same manner as Example 1 except that N-octadecyl-carbamoyl-P-methoxycarbonylbenzene used in the intermediate layer of Example 2 was replaced with calcium stearate (MP 150-165°C). A color thermosensitive recording material was obtained.

The two-color heat-sensitive recording materials of Examples and Comparative Examples obtained as described above were calendered to a smoothness of 1,000 to 2,000 seconds, and then subjected to dynamic color development characteristics and color images using a G-III facsimile test machine. The results of testing for changes over time are shown in Table 1 below.

The test machine was a 8 doso 1”/1” made by Matsushita Electronic Components Co., Ltd.
It has a thermal head of mm, and the heating element resistance is approximately 400Ω.
/ dot 1~, and for 5 color development test 1, the main scanning recording speed is 2 On + sec/1ine, and the sub scanning is 3.85 fl /
nun, platen suppression 3, 0 k(y, / cJ,
The test was conducted under the condition that the head input was 0.67 dots.

A Macbeth densitometer (RD-51/I, filter W-106 black color, V-58 red color) was used for density measurement.

In addition, O1Δ and X in the table mean "good", "slightly bad" and "bad", respectively.

〔effect〕

As can be seen from Table 1, the two-color heat-sensitive recording material of the present invention is
It has high density, excellent two-color separation, and extremely good image stability over time.

Claims (2)

[Claims] (1) In a two-color thermosensitive recording material in which a high-temperature coloring layer, a decoloring layer, and a low-temperature coloring layer are laminated in that order on a support, a bisphenol derivative represented by the following general formula is used as a color developer in the low-temperature coloring layer. A two-color heat-sensitive recording material characterized by: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (Z in the formula is -S-, ▲There are mathematical formulas, chemical formulas, tables, etc.)
and R_1, R_2, R_3 and R_4 represent H or an alkyl group of C_1 to C_4. ) (2) The melting point between the decoloring layer and the low-temperature coloring layer is 110°C to 1
2. A two-color heat-sensitive recording material according to claim 1, further comprising an intermediate layer containing a 40° C. thermofusible substance as a main component.