JPS6242881A - Tow-color thermal recording type label - Google Patents

Abstract

PURPOSE:To improve the color separability of two colors, to prevent the generation of color mixture in a high temp. developed color image and to enhance stability to oil, a plasticizer and water, by containing a color erasing agent capable of applying color erasing action to the color forming system of a low temp. color forming layer in the color erasing layer provided in a high temp. color forming layer or between the high temp. color forming layer and an intermediate layer. CONSTITUTION:A high temp. color forming layer, an intermediate layer based on a water-soluble polymer and a heat-meltable substance, a low temp. color forming layer and an overcoat layer based on a water-soluble polymer are formed to one surface of a support in this order and relase paper is provided to the other surface of said support through an adhesive layer. A color erasing agent capable of applying color erasing action to the color forming system of the low temp. color forming layer is contained in the color erasing layer provided in the high temp. color forming layer or between the high temp. color forming layer and said intermediate layer. The color former used in the low temp. side thermal color forming layer comprises a basic leuco dye forming a stable image by low energy heating and easily receiving the rapid color erasing actin of the color erasing agent by high energy heating. Any color former hardly receiving color erasing action by the color erasing agent may be used in the high temp. side thermal color forming layer and one belonging to a known thermal color forming system is also used without being limited to the leuco dye.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a two-color thermosensitive recording label that utilizes a color-forming reaction between a leuco dye and a color developer.

[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. It is used in In recent years, applications for two-color heat-sensitive recording materials have been expanding, including labels, tickets, coupons, tack paper,
It has also been used for video printers, etc. Conventionally, most thermal recordings have been monochromatic, black or blue, except for those for recorders, but depending on the purpose of the recording, it would naturally be desirable if parts could be colored in different colors. This is a major market need.

Attempts have been made to obtain two-color recording, and various methods and materials have been proposed.

Multi-color thermosensitive recording paper is generally formed by stacking two types of high-temperature and low-temperature coloring layers that develop different tones using different coloring heat energies on a support. It can be divided into two 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
Publication No. 9, Special Publication No. 49-4342, Special Publication No. 49-27
708, JP-A-48-86543, JP-A-49-65239, etc., and the latter is described in JP-A-50-17865 and JP-A-50-17.
These are disclosed in Japanese Patent Publication No. 866, Japanese Patent Publication No. 5], Japanese Patent Publication No. 29024, Japanese Patent Publication No. 51-87542, Japanese Patent Publication No. 36864-1986, Japanese Patent Publication No. 36519-1987, etc., respectively.

However, in the case of the former multicolor thermosensitive recording paper,
During high temperature color development, the color tone that can be specifically achieved by mixing with the color tone of the low temperature color development layer is limited to black threads that have hiding power, such as red-black, blue-black, etc. There is. On the other hand, in the case of the latter type of multicolor thermosensitive recording paper, the combination of color tones can be freely selected, but when coloring at high temperatures, the low temperature coloring layer must be decolored, which requires the use of a decoloring agent. is necessary.

Thermal recording type peelable labels are mainly used for barcodes.
It has been widely applied to S systems, and recently it has been applied to food-related fields, mail delivery system fields, automatic conveyance systems fields such as warehouses, etc. Compared to pre-printed barcodes, thermal barcodes have the advantage of being able to immediately and freely select a code, and also have the advantage of being able to be managed simultaneously using a computer system. Recently, methods have been considered, such as making part of the text on a label a different color than black to make correction points stand out, and different color tones when reading. Recordable labels are desired.

In particular, heat-sensitive recording labels are used in environments where they are likely to come into contact with chemicals (plasticizers, etc.), oil, water, etc., so they are not practical unless the colored image and coloring layer are highly stable against these chemicals. It's hard to say.

〔the purpose〕

Therefore, it is an object of the present invention to provide a two-color sensitizer and recordable label that has good color separation between two colors, does not cause color mixture in high-temperature colored images, and has excellent stability against oil, plasticizers, and water. There is a particular thing.

〔composition〕

According to the present invention, on one side of the support, there is provided a high-temperature coloring layer 4, an intermediate layer mainly composed of a water-soluble polymer and a thermofusible substance, a low-temperature coloring layer, and an overlayer mainly composed of a water-soluble polymer. A coat layer is formed in that order, and a release paper is provided on the other side of the support via an adhesive layer, and a decoloring agent capable of decoloring the coloring system of the low temperature coloring layer is added in or on the high temperature coloring layer. A two-color heat-sensitive recording label is provided in which the dye is contained in a decoloring layer provided between a high-temperature coloring layer and the intermediate layer.

In the present invention, the coloring agent used in the low temperature side thermosensitive coloring layer is:
Any dye may be used as long as it forms a stable image when heated with low energy and is easily erased with a decoloring agent when heated with high energy. In the case of the present invention, a basic leuco dye is used. The coloring agent used in the high-temperature side heat-sensitive coloring layer may be one that is not easily erased by a decoloring agent. Therefore, the coloring agent used in the high-temperature side heat-sensitive coloring layer is not limited to leuco dyes.
Other conventionally known heat-sensitive coloring systems may also be used.

The basic leuco dye used in the low-temperature side heat-sensitive coloring layer of the present invention can be applied alone or as a mixture of two types. For example, triphenylmethane type,
Leuco compounds of dyes such as 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 violet lactone), 3.3-bis(p-dimethyl aminophenyl)-6-diethylaminophenyl, 3.3-bis(P-dimethylaminophenyl)-6-chlorphthalide, 3.3-bis(p-dibutylaminophenyl)phthalide, 3-cyclohexylamino-6-chlorfur Orane, 3-diethylamino-6-chloro-7-methylfluorane.

3-dimethylamino-5,7-dimethylfluorane, 3
-diethylamino-7-chlorofluorane, 3-diethylamino-7-methylfluorane, 3-diethylamino-7,8-benzfluorane, 3-diethylamino-6
-Methyl-7-chlorofluorane, 3(N-p-tolyl-N-ethylamino)-6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2 - (N-(3'-trifluoromethylphenyl)
amino)-6-dinithylaminofluorane, 2-(3,
6-bis(diethylamino)-9-(o-chloroanilino)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-(o-fluoroanilino)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-isoacyl- N-ethyl)amino-7-(0
-chloroanilino)fluoran, 3-(N-hexyl-N-methyl)amino-7-(0-
chloroanilino)fluoran 3-(FJ, N-diethylamino)-5-methyl-7-
(N,N-dibenzylamino)fluoran, benzoylleucomethylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrillospirane, 6'-bromo-3'-methoxy-benzoindolino-pyrillospirane, 3-( 2'-hydroxy-4'-dimethylaminophenyl)-3-(2'-methoxy-5'-chlorophenyl)phthalide, 3-(2'-hydroxy-47-dibutylaminophenyl)-3-(2'- Methoxy-5'-nitrophenyl) phthalide, 3-(2'-hydroxy-4'-diethylaminophenyl)-3-(2'-methoxy-5'-methylphenyl) phthalide, 3-(2'-methoxy- 4'-dimethylaminophenyl)-3-(2'-hydroxy-4'-chloro-5'
-methylphenyl)phthalide, 3-morpholino-7-(N-propyl-trifluoromethylanilino)fluorane, 3-pyrrolidino-7-trifluoromethylanilinofluorane, 3-diethylamino-5-chloro-7-( N-benzyl-trifluoromethylanilino)fluoran, 3-pyrrolidino-7-(di-p-chlorophenyl)methylaminofluoran, 3-diethylamino-5-chloro-7-(α-phenylethylamino)fluoran, 3-(N-ethyl-p-toluidino)-7-(α-phenylethylamino)fluoran, 3-diethylamino-7-(0-methoxycarbonylphenylamino)fluoran, 3-diethylamino-5-methyl-7-( α-phenylethylamino)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, specific examples of basic leuco dyes preferably contained in the high-temperature side coloring layer include 3-diethylamino-7-chlorofluoran, 3-diethylamino-6-methyl-7-chlorofluoran, 3-diethylamino-7-chlorofluoran, and 3-diethylamino-7-chlorofluoran. Examples include cyclohexylamino-6-chlorofluorane, 3-diethylaminobenzo[α]fluorane, and the like.

In the present invention, the high temperature side thermosensitive coloring layer may contain an acidic leuco dye, for example, an acylated lactone type or sultone type leuco dye as shown below.

121 In the present invention, as the color developer for the leuco dye in the high temperature coloring layer and the low temperature coloring layer, for example, N,N'-diphenylthiourea, N-p-ethylphenyl-N'-phenylthiourea, N-p -butylphenyl=N'-phenylthiourea, N,N'-di-m-chlorophenylthiourea,
N,N'-di-P-chlorophenylthiourea, N,N
'-di-m-trifluoromethylphenylthiourea,
N,N'-di-m-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'-5ee-butylidene diphenol, 4.4'
-cyclohexylidene bis(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-terL-butylphenol),
2,2'-dihydroxydiphenyl, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, p
-butyl hydroxybenzoate, benzyl p-hydroxybenzoate, p-chlorobenzyl p-hydroxybenzoate, 〇-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-6 -Zinc naphthoate, 4-hydroxydiphenylsulfone, 4-hydroxy-4'-chlorodiphenylsulfone, bis(4-
hydroxyphenyl) sulfide, 0-sulfophthalimide, 5-isopropyl-〇-sulfophthalimide, 5
In addition to -t-butyl-〇-sulfophthalimide, 5-octyl-〇-sulfophthalimide, etc., a guanidine-based organic base color developer as shown below can also be used.

In the present invention, the coloring system in the high-temperature side thermosensitive coloring layer is not particularly limited, and in addition to the leuco system described above, various systems such as those shown below can be used.

(a) Combination of long-chain aliphatic iron salts such as ferric stearate and ferric myristylate with phenols such as gallic acid and ammonium salicylate.

(b) Organic acid heavy metal salts such as nickel, cobalt, lead, copper, iron, mercury, and silver salts such as acetic acid, stearic acid, and palmitic acid, and alkaline earth metals such as calcium sulfide, strontium sulfide, and potassium sulfide. A combination with a sulfide or a combination of the organic acid heavy metal salt with an organic chelating agent such as S-diphenylcarbazide or diphenylcarbazone.

(c) Heavy metal sulfates such as silver, lead, mercury, thorium sulfates, Na-tetrathionate, sodium thiosulfate,
In combination with sulfur compounds such as thiourea.

(d) a ferric fatty acid salt such as ferric stearate;
Combination with aromatic polyhydroxy compounds such as 3,4-dihydroxytetraphenylmethane.

(e) A combination of an organic noble metal salt such as silver oxalate or mercury oxalate and an organic polyhydroxy compound such as polyhydroxy alcohol, glycerin, or glycol.

(f) Combinations of organometallic salts such as silver behenate and silver stearate and aromatic organic ring-forming agents such as protocatechuic acid, spiroindane, and hydroquinone.

(g) A combination of an aliphatic ferric salt such as ferric pelargonic acid or ferric laurate and a thiocetyl-rubamide or isothiocetyl-rubamide derivative.

(h) A combination of an organic acid lead salt such as lead caproate, lead pelargonate, or lead behenate and a thiourea derivative such as ethylenethiourea or N-dodecylthiourea.

(S) A combination of a higher fatty acid heavy metal salt such as ferric stearate or copper stearate and zinc dialkyldithiocarpanate.

(n) Those that form oxazine dyes, such as the combination of resorcinol and nitroso compounds.

(l) Introduction of an aromatic diazo compound and a coupler.

(w) Combination of formazan compound and metal salt.

In the present invention, in order to bond and support each thermosensitive coloring layer to the support, various conventional binders can be used as appropriate, but it is particularly preferable to use a water-soluble polymer binder. Examples of water-soluble polymers include polyvinyl alcohol, starch and its derivatives, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylic acid amide/acrylic acid ester, etc. Polymer, acrylic acid amide l acrylic ester/methacrylic acid ternary copolymer, styrene/maleic anhydride copolymer alkali salt, isobutylene/maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate,
Gelatin, casein, etc. can be used.

Particularly preferred is polyvinyl alcohol from the viewpoint of binding properties.

As the decolorizing agent used in the present invention, those conventionally used can be used, but (a) the following general formula (1), (II) or (IV
) Piperazine derivatives represented by (b) the following general formula (
tn), and (c) having three or more amide groups in the molecule, or having two or more amide groups and one or more tertiary amine groups. It is preferable to use at least one kind selected from the compounds.

General formula (I) General formula (■) General formula (■): R, 6R7 NGO=A-CON 6R8 General formula (IV): rR5C0NHY □ N N Y2
NHCORI(IVJ In the general formulas (1), (H), (m) and (IV), R
1, R2, R3, R4, R5, R6, R7, R8, R9
and +1to is 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, X, and x2 are carbonyl or sulfonyl, and vl and Y2 represent alkylene. The alkyl represented by R□ to RIO is usually
Examples include linear or branched chains having 1 to 18 carbon atoms, cycloalkyl includes cyclohexyl, aryl includes phenyl, tolyl, xylyl, etc., and aralkyl includes benzyl, phenethyl, etc. etc. These substituents can further have other substituents, such as alkyl, aryl, halogen, alkoxy,
Examples include aryloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, and acylamino. Furthermore, 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, alkoxycarbonylmino, etc. 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-chlorobenzoyl aminoamyl)-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, N-lauryl-N'-benzenesulfonylpiperazine, N-stearyl-N'-benzenesulfonylpiperazine, N-phenyl-N'-butylsulfonyl Piperazine, N-phenyl-N'-laurylsulfosulpiperazine, N-phenyl-N'-stearylsulfonylpiperazine, N-phenyl-N'-cyclohexylsulfonylpiperazine, N-phenyl-N'-benzylsulfonylpiperazine, N -Phenyl-N'-(ρ-methylbenzenesulfonyl)piperazine, N-butyl-N'-(ρ-methylbenzenesulfonyl)
Piperazine, N-benzoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N/-p-methylbenzenesulfonylpiperazine, N-benzoylaminoethyl-N'-benzenesulfonylpiperazine, N-benzoylaminobutyl- N'-benzenesulfonylpiperazine, N-benzoylaminopropyl-N'-butanesulfonylpiperazine, N-naphthoylaminopropyl-N'-benzenesulfonylpiperazine, N-benzenesulfonylaminopropyl-N'-benzenesulfonylpiperazine, N- Butyroylaminopropyl-N'-benzoylpiperazine, N-hexyloylaminopropyl-N'-benzoylpiperazine, N-lauroylaminopropyl-N'-benzoylpiperazine, N-stearoylaminopropyl-N'-benzoylpiperazine, N -stearoylaminopropyl-N'-benzenesulfonylpiperazine, etc.

Specific examples of the compound represented by the general formula (IT) 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(Ill-chlorobenzenesulfonyl)piperazine, N,N'-bis(p-bromobenzenesulfonyl)piperazine, N,N'-bis(butylsulfonyl)piperazine, N
, N'-bis(octylsulfonyl)piperazine, N
, N'-bis(laurylsulfonyl)piperazine, N
, N'-bis(stearylsulfonyl)piperazine, N,N'-bis(cyclohexylsulfonyl)piperazine, N,N'-bis(P-laurylbenzenesulfonyl)
Piperazine, N,N'-bis(cyclohexylsulfonyl)piperazine, N-butylsulfonyl-N'-benzenesulfonylpiperazine, N-octylsulfonyl-N'-benzenesulfonylpiperazine, N-(o-chlorobenzenesulfonyl)N' S
N-lauroyl-N'-benzenesulfonylpiperazine, N-lauroyl-N'-(p-methylbenzenesulfonyl)piperazine, N-benzoyl-N'-benzenesulfonylpiperazine, N-(o-chlorobenzoyl) -N'-benzenesulfonylpiperazine, N-(o-methylbenzoyl)-N'-benzenesulfonylpiperazine, N,N'-bis(butyroyl)piperazine, N,N'
-bis(hexyloyl)piperazine, N,N'-bis(n-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, M,N'-bis(p-methylphenylacetyl)piperazine.

N, N'-bis(phenylacetyl)piperazine, N
, N'-bis(phenylpropionyl)piperazine, N,N'-bis(benzoyl)piverandine, 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-methyl benzoyl)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) In the above general formula (1), R5, R6, R7 and R8
represents substituted or unsubstituted alkyl, cycloalkyl, aryl or aralkyl, R5 and R6 or R7 and R8
can also form a ring by bonding their ends together. The alkyl usually includes a straight chain or branched chain having 4 to 18 carbon atoms, the cycloalkyl includes cyclohexyl, and the aryl includes:
Examples of aralkyl include phenyl, tolyl, xylyl, and the like, and examples of aralkyl include benzyl and phenethyl. These substituents can further have other substituents, and examples of such substituents include alkyl, aryl, alkoxy, acyl, halogen, and heptacylamino such as benzoylamino and acetylamino; Examples include alkoxycarbonylyl, aryloxy, aralkyloxy and the like. A is an aliphatic group or an aromatic group; in the case of an aliphatic group, it is usually substituted or unsubstituted alkylene having 1 to 8 carbon atoms; in the case of an aromatic group, it is substituted or unsubstituted phenylene, tolylene, It is arylene such as xylylene, and in this case, examples of the substituent include the above-mentioned halogen, acylamino, alkoxycarbonyloxy, 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'-tetrastearylsuccinic acid diamide, N,N,N',N'-tetraphenyladipic acid diamide, N,N,N',N'-tetra-P-butylphenyladipic acid diamide, N,N,N', N'-tetraothyladipate diamide, N,N,N', N'-tetraoctyladipate diamide, N,N,N', N'-tetralauryladipate diamide, N, N,N',N'-tetrastearyladipic acid cyamide, N,N'-dicyclohexyl-N,N'-dimethylsuccinic acid diamide, N,N'-dicyclohexyl-N,N'-dimethylglutaric acid diamide, N,N'-dicyclohexyl-N,N'-dimethyladipate amide, N,N,N',N'-tetracyclohexyladipate diamide, N,N'-dimethyl-N,N'- Dicyclohexylsperate diamide, N,N'--dimethyl-N,N'-dicyclohexylsebacic acid diamide, N,N'-dimethyl-N,N'-dicyclohexylmalonic acid diamide, N,N,N',N ' -tetrabenzyladipic acid diamide, adipoyldipiperidine, adiboyldipipecoline, adipoyl-G-E-caprolactam, adipoyldi-
Pyrrolidone, Adiboyl Dipiperidone, Sebacoyl Di-E-caprolactam, Sebacoil Di-Piperidone.

Adipoyl-di-3-chloro-ε-caprolactam, Succinyl-di-3-chloro-ε-caprolactam, etc.

N,N'-terephthaloyl bispiperidine, N,N'
-Isophthaloyl bispiperidine, N, N' -phthaloyl bispiperidine, N, N' -7-phthaloyl bismorboline, N, N' -isophthaloyl bismorpholine, N, N' -phthaloyl bis Morpholine, N.
N'-terephthaloylbis-4-methylpiperazine, N,N'-isophthaloylbis-4-methylpiperazine, N,N'-phthaloylbis-4-methylpiperazine,
N,N'-terephthaloylbis-4-phenylpiperazine, N,N'-isophthaloylbis-4-phenylpiperazine, N,N'-phthaloylbis-4-phenylpiperazine, N,N'-terephthaloy Rubis-4-propylpiperazine, N,N'-isophthaloylbis-4-propylpiperazine, N,N'-phthaloyl-4-propylpiperazine, N
, N'-terephthaloyl biscaprolactam, N, N
'-Isophthaloyl biscaprolactam, N, N'
-phthaloylbiscaprolactam, N,N'-terephthaloylbis-3-chlorocaprolactam, N,N'-isophthaloylbis-3-chlorocaprolactam, N,N'-phthaloylbis-3-chlorocaprolactam, N , N'-terephthalorbisvalerolactam, N, N
'-Isophthaloyl bisvaleractam, N, N'
-phthaloylbiscaprolactam, ~Nj -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-dioctylamine 1~xypropylamine, N,N'-terephthaloylbis-4-chlorobutylamine, N,N'-terephthaloylbis-dibenzoylaminoethylamine, N,N'-isophthaloylbis-dibenzoylaminoethylamine , N,N'-terephthaloylbis-benzoylaminopropylamine, N,N'-isophthaloylbis-benzoylaminopropylamine, N,N'-terephthaloylbis-diacetylaminoethylamine, N,N'- Isophthaloyl bis-diacetylaminoethylamine, N,N'-terephthaloyl bis(4-methylpiperidine), N,N'-terephthaloyl bis(3-methylpiperidine), N,N'-terephthaloyl bis( 3,5-dimethylpiperidine), N,N'-terephthaloylbis(2-methylpiperidine), N,N'-terephthaloylbis(2,6-dimethylpiperidine), N,N'-isophthaloylbis rubis(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'-terephthaloylbis(4-methycarbonylpiperidine), N , N'-isophthaloyl bis(4-methoxycarbonylpiperidine), N,N'-terephthaloyl bis(2-methoxycarbonylpiperidine), N,N'-isophthaloyl bis(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-n-propylpiperidine), N,N'- Isophthaloyl bis(4-butylpiperidine), N,N'-Isophthaloyl bis(4-butylpiperidine).

N,N'-phthaloylbis(4-ethylpiperidine)
, N,N'-phthaloylbis(4-propylpiperidine), N,N'-phthaloylbis(4-butylpiperidine)
N,N'-terephthaloyl bis(3-hydroxymethylpiperidine), N,N'-isophthaloyl bis(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'-terephthaloyl bis(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-phthyl-N'
-cyclohexylamine).

N,N'-phthaloylbis(N-butyl-N'-cyclohexylamine), N,N'-terephthaloylbis(4-ethyloxymethylpiperidine), N,N'-isophthaloylbis(4-ethyloxy methylpiperidine), N,N'-terephthaloylbis(4-ethyloxyethylpiperidine), N,N'-isophthaloylbis(4-ethyloxyethylpiperidine), N,N'-terephthaloylbis rubis(2-methoxyethylpiperidine), N,N'-isophthaloylbis(2-methoxyethylpiperidine), N,N'-terephthaloylbis(4-methoxyethylpiperidine).

N,N'-(isophthaloylbis(4-methoxyethylpiperidine)), N,N'-terephthaloylbis(4-phenylpiperidine), N,N'-isophthaloylbis(4-phenylpiperidine), N,N'-phthaloylbis(4-phenylpiperidine), N,N'-terephthaloylbis(4-phenylpropylpiperidine), N,N'-isophthaloylbis(4-phenylpropylpiperidine), N, N'-phthaloylbis(4-phenylpropylpiperidine) and the like.

In the general formula (IV), R9 and R□. represents 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,
Cycloalkyl includes cyclohexyl,
Examples of aryl include phenyl, tolyl, xylyl, etc., and examples of aralkyl include benzyl, phenethyl, etc. These substituents can further have other substituents, such as alkyl, aryl, halogen, alkoxy, aryloxy, aralkyloxy, acyl, acyloxy, alkoxycarbonyl, carbamoyl, Examples include substituents such as acylamino. (2) 1 and v2 are linear or branched alkylene groups having 1 to 18 carbon atoms.

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

N,N'-bis(benzoylaminoethyl)piperazine, N,N'-bis(benzoylaminopropyl)piperazine, N,N'-bis(benzoylaminobutyl)piperazine, N,N'-bis(cyclohexylamino N-benzoylaminopropyl-N'-cyclohexylaminoethylpiperazine, N-benzoylaminopropyl-N'-benzoylaminobutylpiperazine, N-(P-chlorobenzoylaminoamyl)-N'-benzoylaminopropylpiperazine, N-cyclohexyloylamibutyl-pyl-N'-cyclohexyloylaminobutylpiperazine.

N-naphthoylaminopropyl-N'-benzoylaminopropylpiperazine, N-butyroylaminopropyl-N'-benzoylaminopropylpiperazine, N-lauroylaminopropyl-N'-benzoylaminopropylpiperazine, N-stearoylaminopropyl- N'-benzoylaminopropylpiperazine, N-butyroylaminopropyl-N'-cyclohexyloylaminobutylpiperazine, N-naphthoylaminopropyl-N'-lauroylaminopropylpiperazine, N-naphthoylaminopropyl-N' -stearoylaminopropylpiperazine, etc.

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

N,N',N'-tribenzoyl-diethylenetriamine, N,N',N'-)-ribenzoyl-dipropylenetriamine, N,N',N',N'''-tetrabenzoyl-triethylenetetramine, 1. 7-dibenzoyl-4-methyl-diethylenetriamine, 1,9-dibenzoyl-5-methyl-dipropylenetriamine.

1.7-di-α-naphthoyl-4-methyl-diethyltriamine, 1.7-di-α-naphthoyl-4-cyclohexyl-diethylenetriamine, N, N', N"-tripivaloyl-diethylenetriamine, N, N', N' , N"'-tetraacetyl-triethylenetetramine, N, N', N', N""-tetracyclohexyloyl-triethylenetetramine, ethylenediaminetetraacetic acid tetraanilide.

Ethylenediaminetetraacetic acid tetracyclohexylamide, ethylenediaminetetraacetic acid tetra-ter-2-ethylhexylamide, ethylenediaminetetraacetic acid tetralaurylamide, ethylenediaminetetraacetic acid tetrastearylamide, ethylenediaminetetraacetic acid tetrapiperidide, ethylenediaminetetraacetic acid tetra-ε-cabrolactamide, etc.

In addition, polyethers, polyethylene glycol derivatives, solid alcohols, aliphatic or aromatic amines, guanidine derivatives, morpholine derivatives, etc. can be used as decolorizing agents.

In the present invention, the decoloring agent described above is contained in the high-temperature coloring layer, or is contained in a decoloring layer provided between the high-temperature coloring layer and the intermediate layer described below. In the latter case, the decoloring layer preferably contains a water-soluble polymer binder such as the one exemplified in connection with the heat-sensitive coloring layer.

481 In the present invention, in order to prevent a decrease in the density of a low-temperature colored image due to a decoloring agent, a decoloring layer is provided between a high-temperature coloring layer containing a decolorizing agent and a low-temperature coloring layer, or in one part of the high-temperature coloring layer. An intermediate layer containing a thermofusible substance and a water-soluble polymer as main components is provided between the layer and the low-temperature coloring layer. As the water-soluble polymer in this case, those exemplified in connection with the heat-sensitive coloring layer may be used, but polyvinyl alcohol is particularly preferred from the viewpoint of binding properties and chemical barrier properties. Examples of thermofusible substances include 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,
dialkyl 3,4-epoxy-hexahydrophthalate,
50-2 of higher ketones, other thermofusible organic compounds, etc.
Examples include those having a melting point of about 00°C. Such a thermofusible substance can also be included in the thermosensitive coloring layer.

One of the low-temperature coloring layers is provided with an overcoat layer whose main component is a water-soluble polymer. As for the water-soluble polymer in this case, those exemplified above for the thermosensitive coloring layer can be used. The use of polyvinyl alcohol is particularly preferred from the viewpoint of binding properties and chemical barrier properties.

In addition, wax, other waxy substances, thermosetting organic fillers, etc. may be added to the overcoat layer in order to improve the matching property with the thermal head.

In addition, in the present invention, each heat-sensitive coloring layer, intermediate layer, and decoloring agent layer may optionally contain auxiliary additive components commonly used in this type of heat-sensitive recording material, such as fillers, surfactants, etc. Can be used together.

In this case, examples of fillers include calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, and clay.

Examples include inorganic fine powders such as talc, surface-treated calcium and silica, and organic fine powders such as urea-polymarine resin, styrene/methacrylic acid copolymer, and polystyrene resin.

When a water-soluble polymer is contained as a binder in each of the above-described heat-sensitive coloring layer, intermediate layer, overcoat layer, and decoloring layer,
It can be used together with a conventional water-resistant agent that can make water-soluble polymers water-resistant. Examples of this water-resistant agent include formalin, glyoxazole, chromium-light melamine, melamine-polymarin, polyamide resin, polyamide-epichlorohydrin resin, etc. It will be done. By adding this water-resistant agent to each layer, it is possible to obtain the advantage that the binding property is improved and the layer does not dissolve even when it comes into contact with water.

As described above, a release paper is provided on the other side of the support with a high-temperature thermosensitive coloring layer, an intermediate layer, a low-temperature coloring layer, an overcoat layer, etc. provided on one side via an adhesive layer.

In this case, the adhesive used to attach the release paper to the back surface of the support is usually polyvinyl alcohol, polyvinyl acetate, polyacrylic acid, or a copolymer thereof. Further, as the release paper, one coated or impregnated with a silicone compound is usually used.

〔Example〕

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

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-A]

3-(N-ethyl-N-amylamino)-6-methyl-
7-anirite fluorane (black) 20 parts 10% polyvinyl alcohol aqueous solution 2oII water
60II [Dispersion-B] 3.3-dichlorophenylthiourea 10 parts Calcium carbonate 10I/10%
Polyvinyl alcohol aqueous solution 201/water
60〃[Dispersion-〇] 3-diethylamino-7-lylorfluorane (red) 2
0 parts 10% polyvinyl alcohol aqueous solution 2011 water
60Il [Dispersion -〇] Bisphenol A 10 parts Calcium carbonate 1 on 10% polyvinyl alcohol aqueous solution 15I/water
65. Take 10 parts of the dispersion A prepared as above, 870 parts of the dispersion, and 20 parts of water, mix and stir, and further add 0.2 parts of polyamide resin as a water-resistant agent to form thermosensitive coloring for low temperature. I got the liquid. On the other hand, 10 parts of dispersion liquid, 070 parts of dispersion liquid
and 20 parts of water, mixed and stirred, and further added 0.2 parts of polyamide resin as a water-resistant agent to obtain a thermosensitive coloring layer forming liquid for high-temperature coloring.

Further, a decolorizer layer forming liquid, an overcoat layer forming liquid, and an intermediate layer forming liquid were prepared in the following proportions.

[Decolorizer layer forming liquid]

4.4-dithiodimorpholine 20 parts 1
0% polyvinyl alcohol aqueous solution 2oII water

6o//Waterproofing agent polyamide resin 0.2
1/[Overcoat layer forming liquid] 10% polyvinyl alcohol aqueous solution 500 parts Thermosetting organic filler 10! ! Water resistance agent polyamide resin 5 tt water
501
/ [Intermediate layer forming liquid] 10% polyvinyl alcohol aqueous solution 100 parts Stearic acid amide 10! l water
100
#Waterproofing agent polyamide resin 1 tt Next, on one side of commercially available high-quality paper of about 52 g/rrr per tsubo area,
After sequentially applying and drying the high temperature thermosensitive color forming layer forming liquid (dry coating amount: 5 g/d) and decoloring agent layer forming liquid (dry coating amount: 2.5 g/rn'), apply the intermediate layer forming liquid (dry coating amount: 2.5 g/rn'). Amount 2.
0 g/rrf) was coated and dried, and then a low temperature heat-sensitive coloring layer forming liquid (dry coating amount: 3.5 g/rf) was coated and dried, and finally an overcoat layer forming liquid (dry coating amount: 3.5 g/rf) was coated and dried. g/i) was applied and dried, and then the surface was calendered. Subsequently, a release paper coated with silicone resin with an adhesive layer provided on the silicone resin side was attached to the back side of the support via the adhesive layer, and then punched out to an appropriate size. A two-color heat-sensitive recording label was obtained.

Comparative Example 1 A comparative sample in which no overcoat layer was formed in Example 1 was obtained.

Example 2 A two-color heat-sensitive recording label was obtained in the same manner as in Example 1, except that the water-resistant agent in each layer was removed.

Example 3 A two-color heat-sensitive recording label was obtained in the same manner as in Example 1 except that the polyvinyl alcohol in each layer was replaced with hydroxyethyl cellulose.

The two-color heat-sensitive recording type labels of Examples and Comparative Examples obtained as described above were tested for dynamic color development and color image change over time using a G-m facsimile test machine.The results are shown in Table 1 below. show.

The test machine was an 8 dot/l manufactured by Matsushita Electronic Components Co., Ltd.
It has a 111 thermal head, and the heating element resistance is approximately 400Ω.
The color development test was performed at main scanning recording speed = 55.
- 20msec/1ine, sub-scanning 3.85 Q 7mm
, platen suppression 3.0kg/cJ, head input 0.61
The test was carried out under the conditions of i1/dot. The energy applied to the low-temperature coloring layer was Omj/dot, and the energy applied to the high-temperature coloring layer was 3.0 m,j/dot.

In addition, a Macbeth densitometer (RD-514, filter W-106 black coloring, -158 red coloring) was used for density measurement.

Plasticizer resistance: The sample obtained in the color development test was covered with a plasticizer-containing food wrap film, and a load of 100 g/d was applied in an environment of 40°C, and the colored area was measured after 24 hours. The concentration of was measured using a Macbeth densitometer.

Oil resistance: Cottonseed oil was applied to the colored area of the sample obtained in the color development test, and the concentration was measured using a Macbeth densitometer after being left in a 40°C environment for 24 hours.

Water resistance: 2 samples obtained from the color development test.
After immersion in water at 0° C. for 2 hours, the concentration was measured using a Macbeth densitometer.

Water solubility...The sample obtained in the color development test was heated at 20°C.
After soaking in water for 2 hours, rub the colored layer with your finger 10 times to test the solubility of the layer.

O...Does not dissolve.

X: There is dissolution and peeling of the layer.

Table 1 [Effects] As can be seen from the results in Table 1, the two-color heat-sensitive recording label of the present invention has less image decolorization due to plasticizers, oil, water, etc., and is especially effective as a water-soluble polymer. When polyvinyl alcohol is used together with a waterproofing agent, the image stability is further improved and the layer is not dissolved by water, resulting in extremely high reliability.

Claims (2)

[Claims] (1) On one side of the support, a high-temperature coloring layer, an intermediate layer mainly composed of a water-soluble polymer and a thermofusible substance, a low-temperature coloring layer, and an overcoat layer mainly composed of a water-soluble polymer. A release paper is provided on the other side of the support via an adhesive layer, and a decoloring agent capable of decoloring the coloring system of the low-temperature coloring layer is added in or with the high-temperature coloring layer. A two-color heat-sensitive recording label which is contained in a decoloring layer provided between the intermediate layer. (2) A water-soluble polymer is used as a binder for the high-temperature coloring layer, low-temperature coloring layer, and decoloring layer, and each of the high-temperature coloring layer, decoloring layer, intermediate layer, low-temperature coloring layer, and overcoat layer is waterproof. A two-color thermosensitive recording label according to claim 1, which contains a curing agent.