JPS6233671A - Two color heat sensitive recording materials - Google Patents

Abstract

PURPOSE:To obtain not only the low temperature coloration of black series but also the distinct high temperature coloration without color mixture and to prevent the elapsed color erasing of coloring picture, by a method wherein the first middle layer is provided between the high temperature coloring layer and the color erasing layer and at the same time, the second middle layer is established between the color erasing layer and the low temperature coloring layer. CONSTITUTION:When the first middle layer of a comparatively high softening point is placed between the high temperature coloring layer and the color erasing layer in the two-color heat sensitive recording material in which the high temperature coloring layer, the color erasing layer, and the low temperature coloring layer are successively laminated on the basic materials, the effect of color erasing agent onto the high temperature coloring layer at high temperature coloration, is decreased. Further, if the second middle layer of comparatively low softening point is provided between the low temperature coloring layer and the color erasing layer, the influence of the hiding color agent on the low temperature coloring picture due to the elapse of time is prevented and at the same time, the color erasing action of color erasing agent onto the low temperature coloring layer at high temperature coloring time, is not disturbed. Therefore, the coloring density of the high temperature coloring layer becomes high, and the color separating property between the high temperature coloration and the low temperature coloration becomes high. Furthermore, the storage stability of the low temperature coloring picture becomes high.

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 formed by laminating heat-sensitive coloring layers 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 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.
Publication No. 17865, 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 one color tone can be freely selected. polyethylene glycol derivatives,
Acetamide, stearamide, phthalonitrile as nitrogen-containing organic compounds, guanidine derivatives 1 morpholine derivatives as amine derivatives, etc. are used. but,
In such multicolor recording materials, it has now been found that images produced by the low-temperature coloring layer tend to fade over time due to the influence of the decoloring agent layer.

〔the purpose〕

The present invention can obtain blackish low-temperature coloring, and
To provide a two-color recording material capable of obtaining clear high-temperature coloring without color mixture and without decoloring of a colored image over time.

〔composition〕

According to the present invention, in a two-color thermosensitive recording material in which a high temperature coloring layer, a color erasing layer and a low temperature coloring layer are sequentially laminated on a support, a relatively high softening layer is provided between the high temperature coloring layer and the color erasing layer. A first intermediate layer containing a film-forming polymeric binder as a main component is provided, and a film-forming polymeric binder having a relatively low softening point is provided between the decoloring layer and the low-temperature coloring layer. The second medium rIJff as a component
A two-color heat-sensitive recording material characterized in that it is provided with a layer is provided.

In the present invention, by providing the first intermediate layer having a relatively high softening point between the high temperature color forming layer and the color erasing layer, the influence of the color erasing agent on the high temperature color forming layer during high temperature color development is reduced. In addition, by providing a second intermediate layer with a relatively low softening point between the low-temperature coloring layer and the decoloring layer, it is possible to prevent the decolorizing agent from affecting the low-temperature coloring image over time, and also to prevent the decolorizing agent from affecting the low-temperature coloring image during high-temperature coloring. The color erasing action of the color erasing agent on the low temperature coloring layer is not inhibited. Therefore, in the two-color heat-sensitive recording material according to the present invention,
The coloring density of the high-temperature coloring layer is high, the color separation between high-temperature coloring and low-temperature coloring is high, and the storage stability of the low-temperature coloring image is high.

The softening point of the relatively high softening point film-forming polymeric binder contained in the first intermediate layer is preferably 100°C or higher, more preferably 100°C to 200°C. Examples of such binders include polyvinyl alcohol, polyurethane,
Hydroxyethylcellulose.

Mention may be made of carboxymethyl cellulose, starch and derivatives thereof, but the invention is not limited thereto. On the other hand, the softening point of the film-forming polymeric binder with a relatively low softening point contained in the second intermediate layer is preferably:
100°C or less, more preferably 40 to 100°C,
In this case, it goes without saying that the softening point of the binder in the first intermediate layer is lower than that of the binder in the first intermediate layer. Examples include vinyl/vinyl acetate copolymer, styrene/butadiene/acrylic copolymer, etc., but the present invention is not limited to these. Although it is the main component, a thermofusible substance (such as a sensitizer) or a filler may be contained in each intermediate layer.

In the present invention, examples of the color developer contained in the high-temperature coloring layer and the low-temperature coloring layer include N,N'-diphenylthiourea, N-p-ethylphenyl-N'-phenylthiourea, and N-p-butylphenyl. ~N'-phenylthiourea, N,N'-di-m-chlorophenylthiourea, N
, N'-di-p-chlorophenylthiourea, N, N'
-di-m-trifluoromethylphenylthiourea,
N,N'-g1-methylphenylthiourea, 4,4'
-isopropylidene 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'-isopropylidene bis(2-tert,-butylphenol),
4.4'-5ec-butylidene diphenol, 4.4'
-Cyclohexylidenebis(2-methylphenol)
, 4 tert-butylphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, 3,5-xylenol, thymol, methyl-4-hydroxybenzoate, 4-hydroxyacetophenone, novolak type phenolic resin, 2
,2'-thiobis(4,6-dichlorophenol),
Catechol, resorcinol, hydroquinone, pyroganol, phloroglucin, phloroglycin carboxylic acid, 4-t
ert-octylcatechol, 2,2'-methylenebis(4-chlorophenol), 2,2'-methylenebis(4-methyl-6-jertnibutylphenol),
2,2'-dihydroxydiphenyl, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, P-
Butyl hydroxybenzoate, benzyl p-hydroxybenzoate, p-chlorobenzyl p-hydroxybenzoate, 0-chlorobenzyl p-hydroxybenzoate, ρ-
P-methylbenzyl hydroxybenzoate, n-octylbenzoic acid P-hydroxybenzoate, zinc salicylate, ■-hydroxy-2-naphthoic acid, 2-hydroxy-
6-naphthoic acid, zinc 2-hydroxy-6-naphthoic acid, 4-hydroxydiphenylsulfone, 4-hydroxy-4'-chlorodiphenylsulfone, bis(4-hydroxyphenyl)sulfide, etc. are used, as well as the following: A guanidine-based organic base color developer may also be used.

The leuco dyes used in the present invention can be applied singly or in combination of two or more types, but 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-His(p-dimethylaminophenyl)-phthalide, 3.3-bis(ρ-dimethylaminophenyl)-6-dimethylaminophthalide (also known as crystal violet lactone), 3.3-bis(p- dimethylaminophenyl)-6-diethylaminophenyl, 3.3- His(P-dimethylaminophenyl)-6-
Chlorphthalide, 3,3-bis(p-dibutylaminophenyl)phthalide, 3-cyclohexylamino-6-chlorofluoran, 3-dimethylamino-5,7-dimethylfluoran.

3-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-7,8-benzfluorane.

3-diethylamino-6-methyl-7-chlorofluorane, 3-(NP-tolyl-N-ditylamino)-6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7- Anilinofluorane, 2-(N-(3'-)-lifluoromethylphenyl)amino)-6-dinithylaminofluorane, 2-(
3,6-bis(diethylamino)-9-(o-chloroanilino)xantylbenzoic acid lactam), 3-diethylamino-6-methyl-7-(+w-trichloromethylanilino)fluoran, 3-diethylamino-7-(o -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-pyrylosbilane.

6'-bromo-31-methoxy-benzoindolino-pyrylospirane, 3-(2'-hydroxy-4'-dimethylaminophenyl)-3-(2'-methoxy-5'-chlorophenyl) phthalide.

3-(2'-Hydroxy-4'-dimethylaminophenyl)-3-(2'-methoxy-5'-ditrophenyl)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-(0-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7-(α-phenylethylamino) Fluoran, 3-diethylamino-7-piperidinofluoran, 2-
Chloro-3-(N-methyltoluidino)-7-(ρ-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, specific examples of particularly preferable leuco dyes to be included 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. 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 decolorizing agent include: showing basicity, being soluble in water, having a melting point of at least 80°C, and being stable in air or against heat. .

Examples include low toxicity. Examples of such decolorizing agents include the following.

(a) a piperazine derivative represented by the following general formula (summer), (If) or (IV), (b) a disubstituted amide compound of a dihydric carboxylic acid represented by the following general formula (m), and (
c) Compounds having three or more amide groups in the molecule, or two or more amide groups and one or more tertiary amine groups. General formula (I) 2 General formula (■): General formula (■) 2 General formula (■): In the general formula (1), (II), (m) and (rV),
R□, R2, R3, R4, R5, R6, R7, R8, R
9 and RIO are alkyl, cycloalkyl, aryl or aralkyl which may have a substituent, and R5
The terminals of 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, Xl and x2 are carbonyl or sulfonyl, and ■□ and v2 represent alkylene. The alkyl represented by R1 to RIO is usually 1,
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,
Examples include aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, and acylamino. The piperazine ring in general formulas (1), (n) and (IV) also has one or more substituents such as alkyl, aryl, halogen, alkoxy, aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, acylamino, etc. Two or more may be combined.

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'-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'-(p-methylbenzenesulfonyl)piperazine, N-butyl-N'-(p-methylbenzenesulfonyl) piperazine, N-/<nzoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N'-p-methylbenzenesulfonylpiperazine, N-benzoylaminoethyl-N'-benzenesulfonylpiperazine 1, 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 (II) include the following.

N,N'-bis(benzenesulfonyl)piperazine,
N,N'-bis(P-methylbenzenesulfonyl)piperazine, N,N'-bis(ρ-isopropylbenzenesulfonyl)piperazine, N,N'-bis(p-chlorobenzenesulfonyl)piperazine, N,N'-bis (0-chlorobenzenesulfonyl)piperazine, N,N'-bis(I-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, ! 11. N'-bis(ρ-laurylbenzenesulfonyl)piperazine, N,N'-bis(cyclohexylsulfonyl)piperazine, N-butylsulfonyl-N'-benzenesulfonylpiperazine, N-octylsulfonyl-N'-benzenesulfonylpiperazine.

N-(o-chlorobenzenesulfonyl)-N'-benzenesulfonylpiperazine, N-lauroyl-N'-benzenesulfonylpiperazine.

N-Lauroyl-N'-(p-methylbenzenesulfonyl)piperazine.

N-benzoyl-N'-benzenesulfonylpiperazine, N-(o-chlorobenzoyl)-N'-benzenesulfonylpiperazine, N-(o-methylbenzoyl)-N'-benzenesulfonylpiperazine, NjJ'-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(m-chlorobenzoyl)piperazine, N,N'-bis(0-chlorobenzoyl)piperazine, N,N'-bis(p-methylbenzoyl) /yl)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-phenylbenzoyl)piperazine, N,N'-bis(P-methoxycarbonylbenzoyl)piperazine.

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

In the general formula (m), R5, R6, R7 and R8 represent substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, and R5 and R6 or R7 and R8 are
The ends can also be joined together 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, and examples of such substituents include alkyl, aryl, alkoxy, acyl, halogen, acylamino such as benzoylamino and acetylamino, alkoxy Carbonyl, carbamoyl, aryloxy, aralkyloxy and the like can be mentioned. 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,
Substituted or unsubstituted arylene such as phenylene, tolylene, xylylene, etc., 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 acid diamide, N, N, N', N'-tetraoctylsuccinic acid diamide, N, N, N', N'-tetralaurylsuccinic acid diamide, N, N, N', N'-tetrastearyl succinic acid diamide, N, N, N', N'-tetraphenyl adipic acid diamide, N, N, N', N'-tetra-p-butylphenyl adipic acid diamide, N,N,N',N'-tetrabutyladipate diamide, N,N,N',N'-tetraoctyladipate diamide.

N,N,N',N'-tetralauryladipic acid diamide, N,N,N',N'-tetrastearyladipic acid diamide, N,N'-dicyclohexyl-N,N'-dimethylsuccinic acid diamide , N,N'-dicyclohexyl-N,N'-dimethylglutarate diamide, N,N'-dicyclohexyl-N,N'-dimethyladipate diamide, N,N,N',N'-tetracyclo Hexyladipate 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'-tetrabenzyladipic acid diamide, adipoyldipiperidine, adiboyldipipecoline, adipoyl-di-ε-caprolactam, adipoyldi-
Pyrrolidone, aziboyldipiperidone, sebacoyl di-ε-caprolactam, sebacoyl di-piperidone, adipoyl-di-3-chloro-ε-caprolactam, succinyl-di-3-chloro-ε-caprolactam, and the like.

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'-terephthaloylbis-4-propylpiperazine, N,N'-isophthaloylbis-4-propylpiperazine, N,N'-phthaloyl-4 -propylpiperazine, N
, N'-terephthaloyl biscaprolactam, N, N
'-Isophthaloyl biscaprolactam, N, N'
-phthaloyl biscaprolactam, N,N'-terephthaloyl bis-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'-isophthaloylbis-dioctylamine, N,N'-terephthaloylbis-jethoxypropylamine, N,N'-terephthaloylbis-4-chlorobutylamine, N,N'-terephtha Loylbis-dibenzoylaminoethylamine.

N,N'-isophthaloylbis-dibenzoylaminoethylamine, N,N'-terephthaloylbis-benzoylaminopropylamine, N,N'-isophthaloylbis-benzoylaminopropylamine, N,N'-tere Phthaloylbis-diacetylaminoethylamine, N,N'-isophthaloylbis-diacetylaminoethylamine, N,N'-terephthaloylbis(4-methylpiperidine), N,N'-terephthaloylbis(3- methylpiperidine), N,N'-terephthaloylbis(3,5-dimethylpiperidine).

N,N'-terephthaloylbis(2-methylpiperidine), N,N'-terephthaloylbis(2,6-dimethylpiperidine), N,N'-isophthaloylbis(4-methylpiperidine), N,N'-phthaloylbis(4-methylpiperidine)
, N,N'-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'-terephthaloylbis(4-butylpiperidine), N,N'-isophthaloylbis(4-ethylpiperidine), N,N' -Isophthaloylbis(4-normalpropylpiperidine), N,N'-Isophthaloylbis(4-butylpiperidine), N,N'-Isophthaloylbis(4-butylpiperidine), N,N'- Phthaloyl bis(4-ethylpiperidine)
, N,N'-phthaloylbis(4-propylpiperidine), N,N'-phthaloylbis(4-butylpiperidine)
, N,N'-terephthaloylbis(3-hydroxymethylpiperidine), N,N'-isophthaloylbis(3-hydroxymethylpiperidine), N,N'-phthaloylbis(3-hydroxymethylpiperidine), N , N'-terephthaloylbis(5-ethyl-2-methylpiperidine), N,N'-isophthaloylbis(5-ethyl-2-methylpiperidine), N,N'-phthaloylbis(5-ethyl- 2-methylpiperidine), N,N'-terephthaloylbis(N-ethyl-N'
-cyclohexylamine), N,N'-isophthaloylbis(N-ethyl-N'
-cyclohexylamine), N,N'-phthaloylbis(N-ethyl-N'-cyclohexylamine), N,N'-terephthaloylbis(N-propyl-N'
-cyclohexylamine), N,N'-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'-cyclohexylamic), N,N'-terephthaloylbis(4-ethyloxymethylpiperidine).

N,N'-Isophthaloylbis(4-ethyloxymethylpiperidine).

N,N'-terephthaloyl bis(4-ethyloxyethylpiperidine), N,N'-isophthaloyl bis(4-ethyloxyethylpiperidine), N,N'-terephthaloyl bis(2-methoxyethyl piperidine), N,N'-isophthaloylbis(2-methoxyethylpiperidine), N,N'-terephthaloylbis(4-methoxyethylpiperidine), N,N'-(isophthaloylbis(4-methoxyethylpiperidine) methoxyethylpiperidine).

N,N'-terephthaloylbis(4-phenylpiperidine).

N,N'-Isophthaloylbis(4-phenylpiperidine).

N,N'-phthaloylbis(4-phenylpiperidine), N,N'-terephthaloylbis(4-phenylpropylpiperidine), N,N'-isophthaloylbis(4-phenylpropylpiperidine), N,N '-phthaloylbis(4-)23luprobylpiperidine), etc.

In the general formula (rV), R3 and R□. represents alkyl, cycloalkyl, aryl or aralkyl which may have a substituent. 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. I can list 5 equal powers. 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(cyclohexylaminopropyl)piperazine, N,N'-bis(hexylo ylaminopropyl)piperazine, N-benzoylaminopropyl-N'-cyclohexylaminoethylpiperazine, N-benzoylaminopropyl-N'-benzoylaminobutylbiperazine, 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-naphthoylaminopropyl-N'-stearoylaminopropylpiperazine, and the like.

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 group include the following.

N,N',N'-)-ribenzoyl 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'-tripivaloyl-diethylenetriamine, N,N',N',N"'-tetra Acetyl triethylenetetramine, N, N', N', N''-tetracyclohexyloyl-triethylenetetramine, ethylenediaminetetraacetic acid tetraanilide, ethylenediaminetetraacetic acid tetracyclohexylamide, ethylenediaminetetraacetic acid tetra-2-ethylhexylamide, ethylenediamine 4 Acetic acid tetralaurylamide, ethylenediaminetetraacetic acid tetrastearylamide, ethylenediaminetetraacetic acid tetrapiperidide, ethylenediaminetetraacetic acid tetra-ε-cabrolactamide, etc.

Other decolorizing agents include polyether, polyethylene glycol derivatives, solid alcohol, guanisine derivatives,
Morpholine derivatives and the like can be used.

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 bond and support the high-temperature and low-temperature color forming layers comprising the leuco dye and color developer and the decoloring layer comprising the decoloring agent on the support, various conventional binders may be used as appropriate. For example, polyvinyl alcohol, starch and its derivatives, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylic amide/acrylic ester copolymer, acrylic acid Amide/acrylic acid ester/methacrylic acid 3
In addition to water-soluble polymers such as original copolymers, styrene/maleic anhydride copolymer alkali salts, isobutylene/maleic anhydride copolymer alkali salts, polyacrylamide, sodium alginate, gelatin, and casein, polyvinyl acetate, polyurethane , styrene/butadiene copolymer, polyacrylic acid, polyacrylic acid ester, vinyl chloride/vinyl acetate copolymer, polybutyl methacrylate, ethylene/
Latexes such as vinyl acetate copolymers and 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,
Examples include fine inorganic powders such as clay, talc, and surface-treated calcium and silica, as well as fine organic powders such as urea-formalin resin, styrene/methacrylic acid copolymer, and polystyrene resin. As a fusible substance, 1
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.

〔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.
Two dispersions A to D were prepared by pulverization and dispersion to a particle size of 3 μm.

[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] 3.3-Dichlorophenylthiourea 10 parts Calcium carbonate 10 Polyvinyl alcohol (10% aqueous solution) 207/water
60
〃〃〇〇〇〃 3-diethylamino-7-lyrofluorane (red) 2
0 parts 10% hydroxyethyl cellulose aqueous solution 20 water
6
0 [Dispersion-D] Bisphenol A 10 parts Calcium carbonate 10H2O% Hydroxyethylcellulose 15 Water
65 310 parts of the dispersion prepared above, 870 parts of the dispersion, and 20 parts of water were each taken and mixed and stirred to obtain a thermosensitive color forming liquid for low temperature use. On the other hand, 10 parts of dispersion liquid, 070 parts of dispersion liquid,
20 parts of water were each taken and mixed and stirred to obtain a thermosensitive coloring layer forming liquid for high temperature coloring.

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

[Decolorizer layer forming liquid]

4.4-dithiodimorpholine 20 parts 1
0% polyvinyl alcohol aqueous solution 20II water

60 Next, on top of a commercially available high-quality paper with a basis weight of 52 g/rri, the high-temperature color forming layer forming liquid was applied and dried to a dry adhesion amount of 5 g/m to form a high-temperature color forming layer. above,
A polyvinyl alcohol (solid content 8%) aqueous solution was applied and dried to a dry adhesion amount of 2 g/rri to form a first intermediate layer, and then the decolorizing agent layer forming liquid was applied to a dry adhesion amount of 2 g/rri. A decoloring layer was formed by coating and drying at a concentration of 3.5 g/m, and polyvinylidene chloride latex (
A second intermediate layer was formed by coating and drying a solution (solid content: 45%) to a dry coating weight of 1.5 g/m, and finally, the low-temperature coloring layer forming liquid was applied to a dry coating weight of 3.5 g/m. A low-temperature coloring layer was formed by coating and drying to a weight of 5 g/-. Then, a calender treatment was performed to obtain a smoothness of 500 to 1500 seconds to obtain a two-color heat-sensitive recording material of the present invention.

Example 2 In the above example, a hydroxyethyl cellulose (solid content 10%) solution was used instead of the polyvinyl alcohol used to form the first intermediate layer, and polychloride used to form the second intermediate layer Styrene/butadiene copolymer (solid content 47.5%) instead of vinylidene latex
A two-color heat-sensitive recording material of the present invention was obtained in the same manner as in Example 1 except that .

Comparative Example 1 A comparative two-color thermosensitive film was produced in the same manner as in Example 1, except that the same polyvinylidene chloride latex as the second intermediate layer was used in place of the polyvinyl alcohol used as the first intermediate layer in Example 1. Obtained recording materials.

Comparative Example 2 A comparative two-color heat-sensitive recording material was obtained in the same manner as in Example 1 except that the first and second intermediate layers were not formed.

The two-color heat-sensitive recording materials of the present invention and comparative two-color heat-sensitive recording materials obtained as described above were tested using a G-m facsimile test machine for dynamic color development and changes in color images over time, and the results are shown in Table 1 below.

The test machine was an 8 dot/r manufactured by Matsushita Electronic Components Co., Ltd.
It has an am thermal head, and the i heating body resistance is about 400Ω.
/ dot, and the color development test was performed at a main scanning recording speed of 20
m5ec/1ine, sub-scanning 3.85 Q/mra,
Platen suppression 3.0kg/a#, head input 0.611
/ Dot conditions.

In addition, a Macbeth densitometer (RD-514, filter 1-106 black coloring, W-58 red coloring) was used for density measurement.

Table-1 *0...Good Δ...Slightly bad ×...Bad [Effect] As seen from Table-1, the two-color thermosensitive recording material of the present invention has low-temperature color development. In addition to being able to obtain high-density black and high-temperature red coloring with good color separation, the low-temperature coloring images obtained are
It has significantly improved stability over time.

Claims (2)

[Claims] (1) In a two-color thermosensitive recording material in which a high-temperature color-forming layer, a color-erasing layer, and a low-temperature color-forming layer are sequentially laminated on a support, a relatively high softening point is formed between the high-temperature color-forming layer and the color-erasing layer. A first intermediate layer containing a film-forming polymer binder as a main component is provided, and a film-forming polymer binder having a relatively low softening point is provided as a main component between the decoloring layer and the low-temperature coloring layer. A two-color heat-sensitive recording material comprising a second intermediate layer. (2) the softening point of the binder in the first intermediate layer is 100°C or higher, and the softening point of the binder in the second intermediate layer is lower than the softening point of the binder in the first intermediate layer; The two-color heat-sensitive recording material according to claim 1, which has a temperature of 100°C or less.