JPS62270380A - Two-color thermal recording material - Google Patents

Abstract

PURPOSE:To obtain a sharp high temp. developed color image having excellent two-color separability and to prevent the decolorization of the developed color image with the elapse of time, by containing 4,4'-dihydroxydiphenylsulfone and a specific bisphenol derivative as the color couplers of a high temp. color forming layer. 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 couplers of the high temp. color forming layer, 4,4'- dihydroxydiphenylsulfone and a bisphenol derivative represented by formula (1) [wherein X is halogen, Y is -SO2- or -C(CH3)2-, m is 1 or 2 and X and Y of left and right benzene rings are substituted at a symmetric position) are contained. Because the aforementioned couplers are contained in the high temp. color forming layer of this two-color thermal recording material, 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 heat-sensitive recording material, and more specifically, the present invention relates to a two-color heat-sensitive recording material, and more specifically, a leuco dye that is usually colorless or slightly pale in color, and a color developer that reacts with the leuco dye when heated to develop a color. It relates to a two-color heat-sensitive recording material comprising a heat-sensitive coloring layer containing as a main component.

[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 them, so they are not only used for magical copying of books and documents, but also for use in various electronic devices such as W machines, facsimile machines, telex machines, etc. It is used in fields such as recording the output of a total of 1jl1 machine, but depending on the purpose of recording, in order to display particularly necessary data and numbers more clearly, the coloring of that part (display color) may be changed to the coloring of other parts. It goes without saying that it would be desirable to be able to record in different colors.

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 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, phthalonitrile as nitrogen-containing organic compounds, guanidine derivatives, morpholine derivatives, etc. as amine-conducting conductors are used. but,
It has been found that 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 and color tone of the high-temperature coloring image.

〔the purpose〕

An object of the present invention is to provide a two-color heat-sensitive recording material that has excellent two-color separation properties, can obtain clear high-temperature colored images, and does not cause the colored images to fade over time.

[Sweeping]

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 successively laminated on a support, and 2, 4,4'-dihydroxy A two-color heat-sensitive recording material is provided, which is characterized in that it contains diphenylsulfone and a bisphenol derivative represented by the following general formula.

General formula (wherein, X is halogen, ■ is -5O2- or -C(C1
l 3) z-1m represents 1 or 2, and X of the left and right benzene rings is blue-converted to \' at the position designated as 2) Bisphenol derivatives represented by the above general formula used in the present invention Specific examples include, but are not limited to, the following.

Since the two-color thermosensitive recording material of the present invention contains the color developer in the high-temperature coloring layer, even in the process of decolorizing the low-temperature coloring image with the decolorizing agent when exposed to high heat energy, the high-temperature coloring image is erased. Since it is not affected by the effects of colorants, the resulting colored images are clear and stable 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, and 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-lyrofluorane, 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-dibutylaminophenyl)-6-dimethylaminophthalide (also known as crystal violet lactone), 3.3-bis(p-dimethylaminophenyl)-6-dibutylaminophenyl, 3.3- His(p-dimethylaminophenyl)-6-chlorophthalide, 3.3-bis(p-dibutylaminophenyl)phthalide, 3-cyclohexylamino-6-chlorofluoran, 3-diethylamino-6-chloro-7-methyl Fluorane.

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-p-tolyl-N-ditylamino)-6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2- (N-(3'-trifluoromethylphenyl)
amine)-6-dinithylaminofluorane, 2-(3
, 6-bis(diethylamino)-9-(o-chloroanilino)xantylbenzoic acid lactam), 3-diethylamino-6-methyl-7-(m-h-lichloromethylanilino)fluoran, 3-diethylamino-7-( o-chloroanilino)fluoran, 3-dibutylamino-7-(0-chloroanilino)fluoran.

3-dibutylamino-7-(0-fluoroanilino)fluorane, 3-N-methyl-N-7mylamino-6-methyl-7-
Anilinofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-(N-acyl- N-ethyl)amino-7-(0
-chloroanilino)fluoran, 3-(N-hexyl-N-methyl)amino-7-(0-
chloroanilino)fluoran 3-(N,N-diethylamino)-5-methyl-7-(
N,N-dibenzylamino)fluorane, benzoylleucomethylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrillospirane, 6'-bromo-37-medoxybenzoindolino-pyrillospirane, 3-(2 '-Hydroxy-4'-dimethylaminophenyl)-3-(2'-Me1-xy5'-chlorophenyl)phthalide, 3-(2'-hydroxy-41-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-trifluoro methylanilino)fluorane, 3-pyrrolidino-7-(di-p-chlorophenyl)methylaminofluorane, 3-diethylamino-5-chloro-7-(α-phenylethylamino)fluorane, 3-(N-ethyl -p-toluidino)-7-(α-phenylethylamino)fluoran, 3-diethylamino-7-(o-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7-(α-phenylethylamino) Fluoran, 3-diethylamino-7-piperidinofluoran, 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, examples of the color developer for the above-mentioned basic leuco dye include N,N'-diphenylthiourea, N-ρ-ethylphininy-N'-phenylthiourea, and N-p-butylphenyl-Nj-phenylthiourea. Urea, N, N'-di-m-chlorophenylthiourea, N,
N'-di-2-chlorophenylthiourea, N, N'
-di-m-1-lifluoromethylphenylthiourea, N
, N'-di-m-methylphenylthiourea, 4,4'
-isopropylidene diphenol, 4゜4'-isopropylidene bis(2-chlorophenol), 4,4' -
Impropylidene bis(2,6-dibromophenol)
, 4,4'-isopropylidene bis(2°6-dichlorophenol), 4,4'-isopropylidene bis(2-methylphenol), 4,4'-isopropylidene bis(2-tert,-butylphenol), 4゜4'-5ec-butylidene diphenol, 4,4'-
Cyclohexylidenebis(2-methylphenol), 4
- jetj-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, biloganol, phloroglucin, phloroglycin carboxylic acid, 4-her
t-octylcatechol, 2,2'-methylenebis(
4-chlorophenol), 2,2'-methylenebis(
4-methyl-6-her-butylphenol), 2,
2'-dihydroxydiphenyl, ethyl P-hydroxybenzoate, propyl P-hydroxybenzoate, butyl p-hydroxybenzoate, benzyl P-hydroxybenzoate, p-chlorobenzyl P-hydroxybenzoate,
P-hydroxybenzoic acid. -Chlorbenzyl, p-methylbenzyl p-hydroxybenzoate, n-octyl p-hydroxybenzoate, sulfuric acid, zinc salicylate, ■-hydroxy-2-naphthoic acid, 2-hydroxy-6-naphthoic acid, Examples include zinc 2-hydroxy-6-naphthoate, 4-hydroxydiphenylsulfone, 4-hydroxy-4'-chlorodiphenylsulfone, and bis(4-hydroxyphenyl)sulfide.

As the decoloring agent used in the present invention, it is possible to use various conventionally known decolorizing agents as shown in the explanation of the prior art described above, and furthermore, as a descendant of the decoloring effect, the following General formula (1), (II), (]
Compounds represented by T[), (IV) and (V), or compounds having three or more amide groups in one 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 (III) General formula (IV) General formula (V) In the above general formulas (1), (rl) and (III), R3 and R2 are alkyl which may have a substituent. , cycloalkyl, aryl or aralkyl, and X is carbonyl or sulfonyl. The alkyl represented by R□ and R2 is usually a straight chain or branched chain having 1 to 18 carbon atoms, and the cycloalkyl is
Examples of aryl include phenyl, tolyl, xylyl, and the like; examples of aralkyl include benzyl, phenethyl, and the like. These substituents can further have other substituents, such as alkyl, aryl,
In addition to halogen, alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, acylamino, etc. can be mentioned. Furthermore, one or more substituents such as alkyl, aryl, halogen, alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, and acylamino are bonded to the piperazine ring in general formulas (r) to (III). may have been done.

Specific examples of the compound represented by the general formula (1) 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'-benzoyl Piperazine, Malauryl-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 (U) 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, and the like.

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

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)piperazinone, N,N
'-bis(phenoxyacetyl)piperazine, N,N
'-bis(p-chlorobenzoyl)piperazine, N,
N'-bis(2-phenoxypropionyl)piperazine and the like.

In the general formula (rV), R1, R2, R3 and R4 represent substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, and R1 and R2 or R3 and R4 are bonded at their terminal ends to form a ring. can also be formed. 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,
Examples include the aforementioned 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'-te1-laoctylsuccinic diamide, N,N,N',N'-tetralaurylsuccinic diamide .

NIN, N'7N' -tetrastearylsuccinic acid diamide, N, N, N', N' -tetraphenyl adipic acid diamide, N, N, N', N' -tetra-P-butylphenyl adipic acid diamide, N , N, N', N' -tetrabutyladipate diamide, N, N, N', N' -tetraoctyladipate diamide, N, N, N', N' -tetralauryl adipate diamide, N,N , N'N' -te1-lastearyl adipate diamide, N, N' -dicyclohexyl-N, N' - dimethylsuccinic acid diamide, N, N' - isophthaloyl bispyrrolidine, N, N'
-phthaloylbis-diethylamine, N,N'-terephthaloylbis-diethylamine, N,N'-isophthaloylbis-diethylamine, N,N'-phthaloylbis-diethylamine, N,N'-terephthaloylbis-diethylamine Propylamine, 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-
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. vl and Y2 are linear or branched alkylene groups having 1 to 18 carbon atoms.

Specific examples of such compounds 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-chlorobenzoylamino)-N'-benzoylaminopropylpiperazine, N-cyclohexylaminopropyl-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-1-tetrabenzoyl-triethylenetetramine, 1.7- Dibenzoyl-4-methyl-diethylenetriamine, 1,9-dibenzoyl-5-methyl-dipropylenetriamine, 1,7-di-α-naphthoyl-4-methyl-diethyl 1
~liamine, 1,7-di-alpha-naphthoyl-4-cyclohexyl-diethylenetriamine, N,N',N'-tripivaloyl-diethylenetriamine, N,N',N''',N''''-tetraacetyl-triethylenetetramine, N, N', N', N"'-tetracyclohexyloyl-triethylenetetramine, etc.

In the present invention, in order to bond and support each heat-sensitive coloring layer on a support, various conventional binders can be used as appropriate, such as polyvinyl alcohol, starch and its derivatives, methoxy cellulose, hydroxyethyl cellulose, carboxy Cellulose derivatives such as methylcellulose, methylcellulose, and 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, polybutyl methacrylate, ethylene/vinyl acetate copolymer, styrene/butadiene/ Latex such as an acrylic copolymer can be used.

In addition, in the present invention, each heat-sensitive coloring layer, intermediate layer, and decoloring agent layer may further contain 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,
Zinc hydroxide? Examples include inorganic fine powders such as lt barium, clay, talc, and surface-treated calcium and silica, as well as organic fine powders such as urea-formalin resin, styrene/methacrylic acid copolymer, and polystyrene resin. , thermofusible substances include 1, for example, 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-dialkyl hexahydrophthalate, higher ketone,
Examples include other thermofusible organic compounds having a melting point of about 50 to 200°C.

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 powder was pulverized and dispersed to a particle size of 3 μm to prepare dispersions A to D.

[Dispersion liquid-8]

3-(N-ethyl-N-amylamino)-6-methyl-
7-anirithufluoran (black) 20 parts 10% hydroxyethyl cellulose aqueous solution 20 water
6Qn [Dispersion-B] 3.3'-Dichlorophenylthiourea 12 parts Stearic acid amide 6II Calcium carbonate 21r Polyvinyl alcohol 10% aqueous solution 30+1 Water
40 no! [Dispersion-〇], 3-diethylamino-7-chlorofluoran (red)
20 parts 10% hydroxyethyl cellulose aqueous solution 20zI water
5Qn [Dispersion-D] 4.4'-dihydroxydiphenylsulfone 12 parts 2
．． 2'-bis(3,5-dibromo-4-hydroxyphenyl)propane 12n calcium carbonate 6 parts 10% hydroxyethylecellulose 301/water

Dispersion A1 prepared in the above manner
0 parts, 50 parts of dispersion B, and 10 parts of water were mixed and stirred to obtain a low temperature thermosensitive color forming liquid. On the other hand, dispersion C
10 parts of the dispersion, 050 parts of the dispersion liquid, and 40 parts of water were mixed and stirred to obtain a high temperature thermosensitive coloring layer forming liquid.

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 aqueous solution 20 water
6011 Next, on a commercially available high-quality paper with a basis weight of about 52 g/rrl, the high temperature thermosensitive color forming layer forming liquid (dry coating amount: 6 g/rn') and decoloring agent layer forming liquid (dry coating amount: 2.0 g/rn') were applied. 5 g/m) was sequentially coated with a low temperature heat-sensitive coloring layer forming liquid (dry coating amount: 1.7 g/m), dried, and then calendered to a smoothness of 500 to 1.500 sec. A two-color thermosensitive recording material was obtained.

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

[Dispersion-E]

Bisphenol Δ 20 parts Calcium carbonate 10 parts 10% polyvinyl alcohol aqueous solution 30 parts Water
40 parts Dispersion liquid-c of Example 1 was used instead of the highly colored layer forming liquid of Example 1.
io part, 30 parts of dispersion liquid-B, and 60 parts of water were mixed and stirred to obtain a high-temperature color forming layer forming liquid of a comparative example. Obtained recording materials.

The two-color heat-sensitive recording material obtained as described above was subjected to a dynamic color density test using a Gm facsimile test machine, and the results are shown in Table 1 below. The test machine had a thermal head of 8 dots/mm made by prosecutor electronic components, and the heating resistance was about 400 Ω dots.Using this, the main scanning recording speed was 20 m5ec/1ine, and the sub-scanning was 3.85 mm.
Regarding Q#nm, platen suppression 3.0kg/A-4 width, head input, low temperature color development is 1. OmJ/dot 1~, high temperature color development is 3. The test was conducted under the condition of OmJ/dot.

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

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 containing dihydroxydiphenyl sulfone and a bisphenol derivative represented by the following general formula. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, X is halogen, Y is -SO_2- or -C(C
H_3)_2-, m represents 1 or 2, and X of the left and right benzene rings is substituted at a position symmetrical to Y.