JPS62270381A - Two-color thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a sharp high temp. developed color image having excellent two-color separability, by using 4,4'-dihydroxydiphenylsulfone as the coupler of a high temp. color forming layer and containing a specific heat-meltable substance. CONSTITUTION:A high temp. color forming layer, a decolorizing layer based on a decolorant and a low temp. color forming layer are successively laminated to a support and, as the coupler of the high temp. color forming layer, 4,4'- dihydroxydiphenylsulfone is used and a heat-meltable substance represented by formula (I) (wherein R is a 10-21C alkyl group and A is a hydrogen atom, an alkyl group or an alkoxycarbonyl group) is contained. In this two-color thermal recording material, because the aforementioned coupler and the heat- meltable substance are contained in the high temp. color forming layer, a high temp. developed color image receives no effect of the action of the decolorant even in a process wherein a low temp. developed color image is decolorized by the decolorant upon the reception of high heat energy and, therefore, the obtained developed color image becomes sharp and a stable image is imparted even with the elapse of time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a two-color thermosensitive recording material. More specifically, heat-sensitive color-forming layers each having different color-forming heat energies and different color tones are sequentially stacked on a support, and furthermore, a color eraser containing a color-erasing agent capable of decolorizing the upper heat-sensitive color-forming layer when heated is used. This invention relates to a two-color thermosensitive recording material provided with a color layer.

[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 a lactone ring, lactam ring, spiropyran ring, etc. in the heat-sensitive coloring layer, and a color developer that develops color by reacting with this leuco dye when heated. Agent (color development aid)
Those containing these are widely used because they have clear color tones and less fogging.

By the way, heat-sensitive recording materials can easily produce colored images just by heating, so they are not only used for copying books, documents, etc., but also for recording various types of information such as calculators, facsimile machines, telex machines, and output records of measuring machines. However, depending on the purpose of recording, in order to display particularly necessary data or numbers more clearly, it is possible to record by changing the color of that part (display color) from the color of other parts. Of course, it is desirable to be able to do so.

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 a specific example of these, the former is published in the Special Publication Act of 1973. -69 Publication,
JP 49-4342, JP 49-27708, JP 48-865113, JP 49-65
239, etc., and the latter is described in Japanese Patent Publication No. 50-17865, Japanese Patent Publication No. 50-17866, Japanese Patent Publication No. 51-29024, Japanese Patent Publication No. 51-87.
These are disclosed in Japanese Patent Application Laid-Open No. 542, Japanese Patent Application Laid-Open No. 18048-1982, Japanese Patent Publication No. 36519-1987, and the like.

However, in the case of the former multicolor thermosensitive recording paper,
When coloring at a high temperature, the color tones that can be specifically achieved by mixing 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-bleed, 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,
Ace-1-amide, stearamide, phthalonitrile as nitrogen-containing organic compounds, guanidine derivatives, morpholine derivatives, etc. as amine derivatives are used. However, in such multicolor recording materials, the high-temperature coloring layer and decoloring agent layer tend to mix with each other during high-temperature coloring, resulting in a decrease in the color density of the high-temperature coloring image and a marked decline in the weather resistance of the image. It turns out that there is something.

〔the purpose〕

SUMMARY OF THE INVENTION An object of the present invention is to provide a two-color thermosensitive recording material that has excellent two-color separation properties, can obtain clear high-temperature color images, and has excellent stability of high-temperature color images.

〔composition〕

According to the present invention, a high temperature coloring layer, a color erasing layer containing a color erasing agent as a main component, and a low temperature coloring layer are sequentially laminated on a support, and 4,4'-dihydroxy There is provided a two-color heat-sensitive recording material characterized by using diphenyl sulfone and containing a thermofusible substance represented by the following general formula.

General formula (wherein, R represents an alkyl group having 10 to 21 carbon atoms, and A represents a hydrogen atom, an alkyl group, or an alkoxycarbonyl group) Specific examples of the thermofusible substance represented by the above general formula used in the present invention Examples include, but are not limited to, the following:

Monomethyl-N-stearyl terephthalic acid amide N-laurylbenzamide N-myristylbenzamide N-palmitylbenzamide N-stearylbenzamide N-stearyl-0-chlorobenzamide N-stearyl-0-methoxybenzamide N-stearyl-0-methylbenzamide, etc. .

Since the two-color heat-sensitive recording material of the present invention contains the color developer and thermofusible substance in the high-temperature coloring layer, it receives high heat energy even during the process of decolorizing the low-temperature coloring image with the decolorizing agent. , the high-temperature colored image is not affected by the action of the decoloring agent, so the colored image obtained is clear.
It also provides stable images over time.

The two-color heat-sensitive recording material of the present invention may optionally contain an intermediate layer between the decoloring agent layer and the low-temperature coloring layer, and between the decoloring agent layer and the high-temperature coloring layer, such as a thermofusible substance or a water-soluble material. A layer containing a synthetic resin, a latex resin, a filler, etc. may be provided, or a protective layer may be provided in the form of one layer or multiple layers on the low-temperature coloring layer.

Furthermore, in the present invention, a back coat layer can be provided on the back surface of the support, an adhesive layer can be provided to form a release paper, and a magnetic layer can be provided to form a magnetic ticket paper. .

In the present invention, specific examples of basic leuco dyes preferably contained in the high-temperature coloring layer include 3-diethylamino-7-chlorofluoran, 3-diethylamino-
Examples include 6-methyl-7-chlorofluoran, 3-cyclohexylamino-6-chlorofluoran, and 3-diethylaminobenzo[α]fluoran.

The basic leuco dyes used in the low-temperature coloring layer are, for example,
Leuco compounds of triphenylmethane-based, fluoran-based, phenothiazine-based, auramine-based, and spiropyran-based dyes are preferably used.

Specific examples of such basic leuco dyes include those shown below.

3.3-bis(p-dimethylaminophenyl)-phthalide, 3.3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide (also known as Crystal Biotes 1-
lactone), 3.3-bis(ρ-dimethylaminophenyl)-6-dibutylaminophenyl.

3.3-bis(p-dimethylaminophenyl)-6-chlorophthalide, 3.3-bis(p-dibutylaminophenyl)phthalide.

3-Cyclohexylamino-6-chlorofluorane.

3-diethylamino-6-chloro-7-methylfluorane.

3-diethylamino-5,7-dimethylfluorane 3-
Diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-
7,8-benzfluorane, 3-diethylamino-6-
Methyl-7-chlorofluorane, 3-(N-phly-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-(o-chloroanilino)fluoran, 3-dibutylamino-7-(o-chloroanilino)fluoran, 3-dibutylamino-7-(0-fluoroanilino)fluoran, 3-N-methyl-N -amylamino-6-methyl-7-
Anilinofluorane, 3-~-methyl-N-cyclohexylamino-6=methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-(N-isoacyl-N -ethyl)amino-7-(0
-chloroanilino)fluorane.

3-(N-hexyl-N-methyl)amino-7-(o-
chloroanilino)fluoran 3-(N,N-diethylamino)-5-methyl-7-(
N,N-dibenzylamino) fluorane, benzoylleucomethylene blue, 6'-chloro-8'-methoxybenzoindolino-pyrylospirane, 6'-bromo-3'-methoxy-benzoindolino-e
Surospirane, 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'-dimethylaminophenyl)-3 -(2'-methoxy-5'-methylphenyl)phthalide, 3-(2'-methoxy-4'-dimethylaminophenyl)-3-(2'-hydroxy-47-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-)dinylethylamino)fluorane , 3-(N-ethyl-ρ-toluidino)-7-(α-phenylethylamino)fluoran, 3-diethylamino-7-(o-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7- (α-phenylethylamino)fluorane, 3-diethylamino-7-piperidinofluorane, 2-
Chloro-3-(N-methyltoluidino)-7-(p-n
-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, the color developer for the basic leuco dye mentioned above includes 1, for example, N,N'-diphenylthiourea, N-p-ethylphenyl-N'-phenylthiourea, N-ρ-butylphenyl-N' -phenylthiourea, N, N' -di-m-chlorophenylthiourea, N,
N'-di-ρ-glorophenylthiourea, N, N'
-di-m-trifluoromethylphenylthiourea, N,
N'-di-m-methylphenylthiourea, 4,4'-
Impropylidene diphenol, 4゜4'-isopropylidene bis(2-chlorophenol), 4,4'-isopropylidene bis(2,6-dibromophenol),
4,4'-isopropylidene bis(2゜6-dichlorophenol), 4,4'-isopropylidene bis(2
-methylphenol), 4,4'-isopropylidenebis(2-terj-butylphenol), 4°4'
-5ec-butylidene diphenol, 4.4' -
Cyclohexylidenebis(2-methylphenol), 4
-Lert: -Butylphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, 3,5-xylenol.

Thymol, methyl-4-hydroxybenzoate, 4-
Hydroxyacetophenone, novolac type phenolic resin, 2,2'-thiobis(4,6-dichlorophenol), catechol, resorcinol, hydroquinone, pyroganol, phloroglucin, phloroglycin carboxylic acid,
4-t, ert nioctylcatechol, 2,2'-
Methylenebis(4-chlorophenol), 2,2'-methylenebis(4-methyl-6-tertibutylphenol), 2,2'-dihydroxydiphenyl, Ethyl P-hydroxybenzoate, Propyl P-hydroxybenzoate, P -butyl hydroxybenzoate, benzyl p-hydroxybenzoate, p-chlorobenzyl p-hydroxybenzoate, 0-chlorobenzyl p-hydroxybenzoate, p-methylbenzyl p-hydroxybenzoate,
n-octyl P-hydroxybenzoate, benzoic acid, zinc salicylate, 1-hydroxy-2-naphthoic acid, 2-
Hydroxy-6-naphthoic acid, 2-hydroxy-〇-naphthoic acid zinc, 4-hydroxydiphenylsulfone, 4
-Hydroxy-4'-chlorodiphenyl sulfone, bis(4-hydroxyphenyl) sulfide and the like.

As the color erasing agent used in the present invention, various conventionally known color erasing agents such as those shown in the explanation of the prior art can be used. Formulas (1), (II), (I
II), compounds represented by (rV) and (V), compounds having three or more amide groups in the molecule, or two or more amide groups and one or more tertiary amino groups, N
, N'-dithiocaprolactam and the like are advantageously used.

General formula (n) General formula (■) General formula (TV) General formula (V) ! In official general formulas (1), (II) and (III), R3
and R2 is alkyl, cycloalkyl, aryl or aralkyl which may have a substituent, and X is carbonyl or sulfonyl. The alkyl represented by R1 and R2 is usually a straight chain or branched chain having 1 to 18 carbon atoms, the cycloalkyl is cyclohexyl, and the aryl is phenyl, tolyl, xylyl, etc. 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. In addition, the piperazine ring in general formulas (1) to (m) also includes alkyl, aryl, halogen, alkoxy, aryloxy,
One or more substituents such as acyl, acyloxy, alkoxycarbonyl, carbamoyl, and acylamino may be bonded.

Specific examples of the compound represented by the general formula (1) include the following.

, ~-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, and the like.

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

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(0-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, etc.

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

N,N'-bis(butyroyl)piperazine, N,N'
-bis(hexyloyl)piperazine, N,N'-bis(n-ofthyloyl)piperazine, N,N'-bis(tertiary octicoil)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 and the like.

In the general formula (IV), R, R2, R3 and R4 represent substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, and R and R2 or R3 and R4 are bonded at their terminals, respectively. It is also possible to form a ring. The alkyl usually includes a straight chain or branched chain having 4 to 18 carbon atoms, the cycloalkyl includes cyclohexyl, the aryl includes phenyl, tolyl, xylyl, etc. Examples of alkyl include benzyl and phenethyl. These substituents can further have other substituents,
Examples of such substituents include alkyl, aryl, alkoxy, acyl, halogen, and acylamino such as benzoylamino and acetylamino, alkoxycarbonyl, carbamoyl, aryloxy, and aralkyloxy. A is a fatty acid 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, xylylene. etc., and in this case, the substituent is,
The above-mentioned halogen and acylamino.

Examples include 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'-Te1
-lastearylsuccinic acid diamide, N, N, N', N'
-Tetraphenyladipic acid diamide.

N,N,N',N'-tetra-P-butylphenyladipate diamide, N,N,N',N'-tetrabutyladipate diamide, N,N,N',N'-tetraoctyladipate diamide, N, N, N', N' -tetralauryl adipate diamide, N, N, N', N' -tetrastearyl adipate diamide, N, N' -dicyclohexyl-N, N' -dimethyl succinic acid Acid diamide, N,N'-isophthaloyl bispyrrolidine, N,N'
-phthaloyl bispyrrolidine, N,N'-terephthaloyl bis-diethylamine.

N,N'-isophthaloylbis-diethylamine, L
N'-phthaloylbis-diethylamine, N,N'
-Terephthaloylbis-dipropylamine, N, N'
-Isophthaloylbis-dipropylamine, N, N'
-Terephtacoylbis-dibutylamine, N,N'-
Isophthaloylbis-dibutylamine, N,N'-terephthaloylbis-cyclohexyl-methylamine, N,N'-isophthaloylbiscyclohexylmethylamine, N,N'-terephthaloylbis- Dicyclohexyl
Amine, N,N'-isophthaloylbis-dicyclohexyl-
Amin et al.

In the general formula (V), R1 and R2 represent alkyl, cycloalkyl, aryl, or aralkyl which may have a substituent. The alkyl usually includes a straight chain or branched chain having 1 to 18 carbon atoms, the cycloalkyl includes cyclohexyl, the aryl includes phenyl, tolyl, xylyl, etc. Examples of alkyl include benzyl and phenethyl. These substituents can further have other substituents, such as alkyl, aryl, halogen, alkoxy, aryloxy,
Examples include substituents such as aralkyloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, and acylamino. (2) and Y2 are linear or branched alkylene groups having 1 to 18 carbon atoms.

Specific examples of such compounds include, for example.

Examples include:

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-chlorobenzoylaminoamino) -N'-
Benzoylaminopropylpiperazine.

N-cyclohexyloylaminopropyl-N'-cyclohexyloylaminobutylpiperazine and the like.

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

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-diα-naphthoyl-4-cyclohexyl-diethylenetriamine, N, N', N' -1~lipivaloyl-diethylenetriamine, N, N', N', N''"-tetraacetyl-triethylenetetramine, N, N', N', N"'-tetracyclohexyloyl-triethylenetetramine, etc.

In the present invention, various conventional binders can be used as appropriate to bind each thermosensitive coloring layer onto the support, such as polyvinyl alcohol, starch and its derivatives, methoxycellulose, hydroxyethylcellulose, Cellulose derivatives such as carboxymethylcellulose, methylcellulose, ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylamide/acrylic ester copolymer, acrylamide/
Water-soluble polymers such as acrylic acid ester/methacrylic acid terpolymer, styrene/maleic anhydride copolymer alkali salt, imbutylene/maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein, etc. In addition, polyvinyl acetate, polyurethane, styrene/butadiene copolymer, polyacrylic acid, polyacrylic acid ester, vinyl chloride/vinyl acetate copolymer.

Latex such as polybutyl methacrylate, ethylene/vinyl acetate copolymer, styrene/butadiene/acrylic copolymer, etc. can be used.

In addition, in the present invention, each heat-sensitive coloring layer, intermediate layer, and decoloring agent layer may further contain 5 auxiliary additive components commonly used in this type of heat-sensitive recording material, such as fillers, surfactants, This can be done by using a thermofusible substance (or lubricant), etc. In this case, the filler includes, for example, calcium carbonate,
Silica, zinc oxide, titanium oxide, aluminum hydroxide,
In addition to inorganic VIl powders such as zinc hydroxide, barium sulfate, clay, talc, and surface-treated calcium and silica,
Examples include fine organic powders such as urea-formalin resin, styrene/methacrylic acid copolymer, and polystyrene resin. Examples of thermofusible substances include higher fatty acids or their esters, amides, gold, and salts. In addition, various waxes, condensates of aromatic carboxylic acids and amines, benzoic acid phenyl esters, higher linear glycols, 3,4-
50 to 200°C for epoxy-dialkyl hexahydrophthalate, higher ketones, and other thermofusible organic compounds, etc.
Examples include those with a melting point of about

In order to obtain the heat-sensitive recording material of the present invention, a liquid in which color-forming dyes, color developers, decolorizers, binders, etc. are dispersed or dissolved is coated on a support such as paper, synthetic paper, or plastic film and dried. ,
You can get it by repeating it. When further laminating on top of the coated layer, it is necessary to pay sufficient attention to solubility, liquid releasability, etc. so that the lower layer does not mix with the upper layer. Further, after the coating is dried, the upper layer may be coated after calendering.

〔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 Each of the following ingredients was prepared using a sand mill to give an average particle size of 2 to 2.
The mixture was pulverized and dispersed to a size of 3 μm to prepare dispersions A to D.

[Dispersion liquid-A]

3-(N-ethyl-N-amylamino)-6-methyl-
7-anirithufluoran (black) 20 parts 10% hydroxyethyl cellulose aqueous solution 2Qtt water
60/l [Dispersion-B] 3.3'-Dichlorophenylthiourea 12 parts Stearic acid amide 5 n Calcium carbonate 2! ! Polyvinyl alcohol 10% aqueous solution 301! water
4Qtp [
Dispersion -〇〕 3-diethylamino-7-lylorfluorane (red) 2
0 parts 10% hydroxyethyl cellulose aqueous solution 2Q water

60! ! [Dispersion -〇] 4.4'-dihydroxydiphenylsulfone 18 parts monomethyl-N-stearyl terephthalic acid amide
5n calcium carbonate
6 parts 10% hydroxyethylecellulose 30? I water
10 parts of the dispersion A prepared as above, 850 parts of the dispersion and 40 parts of water were each taken and mixed and stirred to obtain a low temperature thermosensitive color forming liquid.

On the other hand, cio parts of the dispersion, 050 parts of the dispersion, and 10 parts of water were each taken and mixed and stirred.

A high temperature thermosensitive coloring layer forming liquid was obtained.

Further, a decolorizing agent layer forming liquid for forming a decolorizing agent layer was prepared at the following ratio.

[Decolorizer layer forming liquid]

N,N'-Isophthaloylbiscyclohexylmethylamine 20 parts 10% polyvinyl alcohol water 7 volumes 201/water
5Qn Next, 1 tsubo weight is about 52E/T! On a commercially available high-quality paper, the high-temperature thermosensitive coloring layer forming liquid (dry coating amount: 6 g/rn') and decoloring agent layer forming liquid (dry coating amount: 2.5 g/rn') were sequentially applied at a low temperature. A layer forming liquid (dry coating amount: 1.7 g/rr) was applied and dried, and then calendering was carried out to give a smoothness of 500 to 1,500 seconds to obtain a two-color heat-sensitive recording material of the present invention.

Comparative example 1 Dispersion-E was obtained using the following components in the same manner as in Example 1.

[Dispersion-E]

Bisphenol A 18 parts Ethylene bisstearamide 6 parts Calcium carbonate 6 parts 10% polyvinyl alcohol aqueous solution 30 parts Water
40 parts A two-color heat-sensitive recording material of Comparative Example 1 was obtained in the same manner as in Example 1, except that Dispersion -E of Example 1 was replaced with Dispersion -E.

The two-color thermosensitive recording material obtained as described above was subjected to a dynamic color density test using a G-In facsimile test machine.
The results are shown in Table 1 below. The test machine had a thermal head of 8 dots/ll1111 made of electronic components (1), and a heating resistance of about 400 Ω/dot. /mm, platen suppression 3.0kg/A-
4111, regarding head input, low temperature coloring is 1. o+n
J/dot, high temperature color development is 3. The test was conducted under the conditions of OmJ/dot1-.

Table 1 [Effects] As is clear from Table 1, the two-color thermosensitive recording material of the present invention has a high high temperature color density and is excellent in environmental preservation.

Claims (1)

[Claims] (1) In a two-color thermosensitive recording material in which a high temperature coloring layer, a color erasing layer containing a color erasing agent as a main component, and a low temperature coloring layer are sequentially laminated on a support, as a color developer for the high temperature coloring layer, 4 ,4'-
A two-color heat-sensitive recording material characterized by using dihydroxydiphenyl sulfone and containing a thermofusible substance represented by the following general formula. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R represents an alkyl group having 10 to 21 carbon atoms, and A represents a hydrogen atom, an alkyl group, or an alkoxycarbonyl group.)