JPH0920079A - Thermal recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal recording label which has stickiness, particularly improved stickiness to a PVC lap, has no problem in thermal property, can be lengthened, saves labor to peel off a peeling paper, and can be manufactured with a little resources at low cost. SOLUTION: On a surface of a support body, a thermal coloring layer having, as main components, a colorless or light color leuco dye and a developer is provided. On the rear face of the support body, a pressure sensitive adhesive layer and a barrier layer which is activated by light or heat so as to develop stickiness are arranged in sequence.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive recording material, and more particularly to a heat-sensitive recording material for labels which does not require a release paper.

[0002]

2. Description of the Related Art Generally, a thermosensitive recording material label is provided with a thermosensitive coloring layer mainly composed of a colorless or light colored leuco dye and a color developer on the surface of a support, and peeled through a pressure sensitive adhesive layer on the back surface. Adhesive laminated paper is used. Although such a thermal recording material label is effective, it has many drawbacks. That is, the release paper made of glassine paper or the like is about half the total thickness of the thermal recording medium as a product. Therefore, the length of the heat-sensitive recording label that can be accommodated in the heat-sensitive recording apparatus becomes short, and the heat-sensitive recording label must be replenished frequently. Further, it is necessary to peel off the release paper after printing on the thermosensitive recording medium and before attaching it to the adherend, which is disadvantageous in that it takes time. Further, these release papers must be handled during storage as well as during storage of the heat-sensitive recording label, and must be post-treated even after being removed from the heat-sensitive recording medium. The peeled release paper is discarded as it is, which is a waste of resources. Therefore, such a heat-sensitive recording label has a drawback that the release paper is wasted and the manufacturing cost thereof is high.

In order to eliminate these drawbacks, a heat-sensitive recording label which is not attached with a release paper is disclosed in, for example, Japanese Utility Model Laid-Open No. 59-439.
No. 79, No. 59-46265, JP-A No. 60-54.
No. 842, etc. Further, a microcapsule of an adhesive, a release agent layer for the adhesive provided on a protective layer, and the like have also been proposed. However, many of these have problems in terms of adhesive properties, release properties, thermal properties, as well as printability on the surface of the thermosensitive coloring layer, and conventional pressure-sensitive adhesive labels or release papers using release paper sheets are still used. At present, it is not possible to obtain the same label as the thermal recording label. Further, in general, when a heat activated adhesive is used, the adhesiveness to PVC wrap is poor due to migration of the plasticizer contained in the PVC wrap.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides adhesive properties,
In particular, the adhesiveness to PVC wrap is improved, there is no problem in thermal properties, and the length of the thermal recording label can be increased. Further, the labor of peeling the release paper can be omitted, and in addition, It is an object of the present invention to provide a heat-sensitive recording label that can be manufactured with resources and at low cost.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have earnestly studied a label for heat-sensitive recording which is excellent in adhesive property and thermal property without using release paper and has good printability on a heat-sensitive color developing layer surface. As a result, it was found that a thermosensitive coloring layer provided on the surface of the support, and a pressure-sensitive adhesive layer and a specific barrier layer provided on the back surface of the support in this order meet the above-mentioned object. It came to completion. That is, according to the present invention, a thermosensitive coloring layer containing a colorless or pale leuco dye and a color developer as a main component is provided on the surface of the support, and a pressure-sensitive adhesive layer and light or heat are provided on the back surface of the support. There is provided a heat-sensitive recording material comprising a barrier layer which is activated to develop tackiness in order.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Since the label for heat-sensitive recording of the present invention has the above-mentioned constitution, it does not exhibit adhesiveness under normal conditions and only when necessary, hot air, hot plate, heat roll, light (light → heat conversion). It is not necessary to use a release paper because it exhibits adhesiveness when it is thermally activated by the above-mentioned method, and is excellent in thermal characteristics and printing suitability.

As the pressure-sensitive adhesive used in the present invention, various conventional pressure-sensitive adhesives can be appropriately used. Specific examples thereof include polyvinyl acetate, vinyl acetate / ethylene copolymer, vinyl acetate / acrylic acid ester copolymer,
Vinyl acetate / maleic acid ester copolymer, ethylene /
Acrylic acid copolymers, emulsions and starches such as epoxy resins and phenolic resins, starch, gelatin, casein, polyvinyl alcohol, carboxycellulose, cellulose derivatives such as methylcellulose and hydroxyethylcellulose, and water-soluble resins such as polyvinylpyrrolidone. The invention is not limited to these. The coating amount of the pressure sensitive adhesive layer on a dry basis 5~35g / m ^2, preferably preferably set to 10 to 25 g / m ^2.

Further, the barrier layer which is used in the present invention and which is thermally activated by hot air, a hot plate, a heat roll, light or the like has a delayed tack property, and is a solid plasticizer at room temperature and a tackifier. It is formed by using the agent as a basic component and further adding an infrared absorbing substance and other additives as necessary. Examples of polymers include acrylic resins, acrylic / styrene resins, styrene resins, styrene / butadiene resins, ethylene / acrylic resins, vinyl acetate resins, vinyl acetate / maleic acid resins, ethylene / vinyl acetate. Resin,
Examples thereof include, but are not limited to, methacrylic acid-based resins, vinylidene chloride-based resins, synthetic rubber-based resins, and natural rubber-based resins. Examples of plasticizers that are solid at room temperature include ortho-dicyclohexyl phthalate, dihexyl ortho-phthalate, diphenyl ortho-phthalate,
Ortho-dihydroabietyl phthalate, dimethyl isophthalate, stellulose benzoate, ethylene glycol dibenzoate, trimethylolethane tribenzoate, glyceryl tribenzoate, pentaerythritol tetrabenzoate, stellulose octaacetate, tricyclohexyl citrate, N-cyclohexyl-p-toluenesulfonamide, dehydroabietylamine carbonate, methoxyethyl stearate
Examples include, but are not limited to, urea complexes. Examples of tackifiers include rosin derivatives (polymerized rosin, hydrogenated rosin, pentaerythritol ester of rosin, resin acid dimer), terpene resins, olefin resins, styrene resins, indene resins, alkylphenol resins. Examples thereof include resins, petroleum-based resins, ethyl cellulose, etc., but are not limited thereto.
The blending ratio of the polymer, the plasticizer and the tackifier is 10 to 70:10 to 80, preferably 15 to 60:20 by weight.
˜70: 10 to 40. The coating amount of the barrier layer is preferably from 1 to 20 g / m ² on a dry basis and more preferably 2 to 15 g / m ² or less 2 to 10 g / m ^2. Further, the coating amount of the pressure-sensitive adhesive layer and the barrier layer is 2: 1 or less, preferably 2.5: 1.0 or less in dry weight. If the ratio exceeds 2: 1, the adhesive strength after activation becomes poor, which is not preferable. Further, if necessary, as a specific example of the infrared absorbing substance added to the barrier layer, a near-infrared absorbing dye, a cyanine dye, an azurenium dye, a pyrylium dye,
Thiopyrylium dye, squarylium dye, triarylmethane dye, immonium dye, diimmonium dye, thiol nickel complex salt dye, phthalocyanine dye, naphthalocyanine dye, anthraquinone dye, and triphenyl phosphate, 2- Ethylhexyl diphenyl phosphate, furfuryl acetate, bis (1-thio-2-phenolate) nickel-
Tetrabutylammonium, bis (1-thio-2-naphtholate) nickel-tetrabutylammonium, 1,
1'-diethyl-4,4'-quinocarbocyanine iodide, 1,1'-diethyl-6,6'-dichloro-
Organic compounds such as 4,4′-quinotricarbocyanine iodide may be mentioned. Furthermore, metal oxides such as aluminum oxide, metal hydroxides such as aluminum hydroxide and magnesium hydroxide; dakarite group, takuseki group, pyroxene group, amphibole group, mica group, feldspar group, silica mineral group, Silicate minerals such as clay minerals; Silicate compounds such as zinc silicate, magnesium silicate, calcium silicate and barium silicate; Phosphate compounds such as zinc phosphate; Nitrogen compounds such as trisilicon tetranitride and boron nitride; Barium sulfate; Sulfate compounds such as calcium sulfate and strontium sulfate; carbonate compounds such as calcium carbonate, barium carbonate, magnesium carbonate and zinc carbonate; and inorganic compounds such as nitrate compounds such as potassium nitrate, and further scaly graphite, granular graphite, lump graphite , Natural graphite such as earth-crystal graphite, and human sub-graphite, but are not limited thereto.

The leuco dyes used in the present invention may be applied alone or as a mixture of two or more kinds, and as such leuco dyes, those applied to the recording material of this kind are arbitrarily applied, for example, Triphenylmethanephthalide type, triallylmethane type, fluorane type, phenothidian type, thiofluorane type, xanthene type, indophthalyl type, spiropyran type, azaphthalide type, chromenopyrazole type, methine type, rhodamine anilinolactam type, rhodamine lactam type Leuco compounds such as quinazoline type, diazaxanthene type and bislactone type are preferably used. Examples of such compounds include those shown below. 3,3-bis (p-dimethylaminophenyl) -phthalide 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide 3,3-bis (p-dimethylaminophenyl) -6-diethylaminophthali De 3,3-bis (p-dimethylaminophenyl) -6-chlorophthalide 3,3-bis (p-dibutylaminophenyl) phthalide 3-cyclohexylamino-6-chlorofluorane 3-dimethylamino-5,7-dimethyl Fluoran 3- (N-methyl-N-isoamylamino) -6-methyl-7-anilinofluorane 3- (N-methyl-N-isobutylamino) -6-methyl-7-anilinofluorane 3- (Np-tolyl-N-ethylamino) -6-methyl-7-anilinofluorane 3- (N-methyl-N-amylamino) -6-methyl-
7-anilinofluoran 3- (N, N-di-n-amylamino) -6-methyl-
7-anilinofluoran 3- (N-methyl-N-cyclohexylamino) -6
Methyl-7-anilinofluoran 3- (N-methyl-N-iso-propylamino) -6
-Methyl-7-anilinofluorane 3- (N-ethyl-N-tetrahydrofurfurylamino) -6-methyl-7-anilinofluorane 3-diethylamino-7,8-benzfluorane 3-diethylamino-7 -Chlorofluorane 3-diethylamino-7-methylfluorane 3-diethylamino-6-methyl-7-chlorofluorane 3-pyrrolidino-6-methyl-7-anilinofluorane 3-diethylamino-6-methyl-7- (M-Trichloroanilino) fluorane 3-diethylamino-7- (o-chloroanilino) fluorane 3-dibutylamino-7- (o-chloroanilino) fluorane 3-diethylamino-6-methyl-7-anilinofluorane 3-dibutyl Amino-6-methyl-7-anilinofluorane 3-diethylamino- - methyl-7- (2 ', 4'-
Dimethylanilino) fluoran 3- (N, N-diethylamino) -5-methyl-7-
(N, N-Dibenzylamino) fluorane benzoyl leuco methylene blue 6'-chloro-8'-methoxybenzoindolinospiropyran 6'-bromo-8'-methoxybenzoindolinospiropyran 3- (2'-hydroxy-4'- Dimethylaminophenyl) -3- (2'-methoxy-5'-chlorophenyl)
Phthalide 3- (2'-hydroxy-4'-diethylaminophenyl) -3- (2'-methoxy-5'-nitrophenyl)
Phthalide 3- (2'-methoxy-4'-dimethylaminophenyl) -3- (2'-hydroxy-4'-chloro-5'-
Methylphenyl) phthalide 3-morpholino-7- (N-propyltrifluoromethylanilino) fluorane 3-pyrrolidino-7-trifluoromethylanilinofluorane 3-diethylamino-5-chloro-7- (N-benzyl-tri Fluoromethylanilino) fluorane 3-pyrrolidino-7- (di-p-chlorophenyl) methylaminofluorane 3-diethylamino-5-chloro-7- (α-phenylethylamino) fluorane 3- (N-ethyl-N- p-toluidino) -7- (α-
Phenylethylamino) fluorane 3-diethylamino-7- (o-methoxycarbonylphenylethyl) fluorane 3-diethylamino-5-methyl-7- (α-phenylethylamino) fluorane 3-diethylamino-7-piperidinoaminofluorane 2-chloro-3- (N-methyltoluidino) -7- (p
-N-butylanilino) fluorane 3,6-bis (dimethylamino) fluorenespiro (9,3 ')-6'-dimethylaminophthalide 3- (N-ethyl-N-cyclohexylamino) -5
6-benzo-7-α-naphthylamino-4′-bromofluorane 3-diethylamino-6-chloro-7-anilinofluoran 3- (N-ethyl-N-2-ethoxypropylamino)
-6-Methyl-7-anilinofluorane 3- (N-ethyl-N-tetrafurfurylamino) -6
-Methyl-7-anilinofluoran 3-diethylamino-6-methyl-7-mesitidino-
4 ', 5'-benzofluoran 3- (p-dimethylaminophenyl) -3- {1,1-
Bis (p-dimethylaminophenyl) ethylene-2-yl {phthalide 3- (p-dimethylaminophenyl) -3- {1,1-
Bis (p-dimethylaminophenyl) ethylene-2-yl {-6-dimethylaminophthalide 3- (p-dimethylaminophenyl) -3- (1-p-
Dimethylaminophenyl-1-phenylethylene-2-
Yl) phthalide 3- (p-dimethylaminophenyl) -3- (1-p-
Dimethylaminophenyl-1-p-chlorophenylethylene-2-yl) -6-dimethylaminophthalide 3- (4'-dimethylamino-2'-methoxy) -3-
(1 ''-p-dimethylaminophenyl-1 ''-p-chlorophenyl-1 '', 3 ''-butadiene-4 ''-yl) benzophthalide 3- (4'-dimethylamino-2'-benzyloxy )
-3- (1 ''-p-dimethylaminophenyl-1 ''-phenyl-1 '', 3 ''-butadiene-4 ''-yl) benzophthalide 3-dimethylamino-6-dimethylamino-fluorene-9 -Spiro-3 '(6'-dimethylamino) phthalide 3,3-bis {2- (p-dimethylaminophenyl)-
2- (p-methoxyphenyl) ethenyl} -4,5,
6,7-Tetrachlorophthalide 3-bis {1,1-bis (4-pyrrolidinophenyl) ethylene-2-yl} -5,6-dichloro-4,7-dibromophthalide bis (p-dimethylamino Styryl) -1-naphthalenesulfonylmethane bis (p-dimethylaminostyryl) -1-p-tolylsulfonylmethane and the like.

In the present invention, various electron-accepting compounds such as a phenolic compound, a thiophenolic compound, a thiourea derivative, an organic acid and a metal salt thereof can be used as a developer. Specific examples thereof include the followings, but are not limited to these. 4,4'-isopropylidenediphenol 4,4'-isopropylidene bis-o-methylphenol 4,4'-sec-butylidene bisphenol 4,4'-isopropylidene bis (2-tert-butyl) phenol p- Zinc nitrobenzoate 1,3,5-Tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzylisocyanuric acid 2,2- (3,4′-dihydroxyphenyl) propane bis (4-hydroxy- 3-Methylphenyl) sulfide 4- {β- (p-methoxyphenoxy) ethoxy} salicylic acid 1,7-bis (4-hydroxyphenylthio) 3,5-
Dioxaheptane 1,5-bis (4-hydroxyphenylthio) -3-oxapentane phthalic acid monobenzyl ester monocalcium salt 4,4′-cyclohexylidenediphenol 4,4′-isopropylidenebis (2-chlorophenol ) 2,2′-Methylenebis (4-methyl-6-tert-)
Butylphenol) 4,4'-butylidenebis (6-tert-butyl-2)
-Methylphenol) 1,1,3-tris (2-methyl-4-hydroxy-5)
-Cyclohexylphenyl) butane 4,4'-thiobis (6-tert-butyl-2-methylphenol) 4,4'-diphenolsulfone 4-isopropoxy-4'-hydroxydiphenylsulfone 4-benzyloxy-4'-hydroxy Diphenyl sulfone 4,4'-diphenol sulfoxide p-Hydroxybenzoate isopropyl p-Hydroxybenzoate benzyl protocatechuate benzyl stearyl gallate Steril gallate octyl gallate 1,3-bis (4-hydroxyphenylthio) propane N, N '-Diphenylthiourea N, N'-di (m-chlorophenyl) thiourea salicylanilide bis- (4-hydroxyphenyl) acetic acid methyl bis- (4-hydroxyphenyl) acetic acid benzyl 1,3-bis (4-hydroxyphenyl) ) Benzene 1,4-bis (4-hydroxyphenyl) benzene 2,4'-diphenosulfone 2,2'-diallyl-4,4'-hydroxyphenylsulfone 3,4-dihydroxy-4'-methyldiphenylsulfone 1- Acetyloxy-2-naphthoate zinc 2-acetyloxy-3-naphthoate zinc 2-acetyloxy-1-naphthoate zinc α, α-bis (4-hydroxyphenyl) α-methyltoluene Zinc thiocyanate antipyrine complex tetra Bromobisphenol A Tetrabromobisphenol S 4,4′-thiobis (2-methylphenol) 4,4′-thiobis (2-chlorophenol) and the like.

Further, in the present invention, various heat-fusible substances can be used in combination as the sensitivity improving agent, and specific examples thereof include the followings, but the present invention is not limited thereto. . Fatty acids such as stearic acid and behenic acid, fatty acid amides such as stearic acid amide and palmitic acid amide, zinc stearate, aluminum stearate, calcium stearate, zinc palmitate,
Fatty acid metal salts such as zinc behenate, p-benzylbiphenyl, terphenyl, triphenylmethane, benzyl p-benzyloxybenzoate, β-benzyloxynaphthalene, β-phenyl naphthoate, 1-hydroxy-2-
Phenyl naphthoate, methyl 1-hydroxy-2-naphthoate, diphenyl carbonate, glare coal carbonate, dibenzyl terephthalate, dimethyl terephthalate, 1,4-dimethoxynaphthalene, 1,4-diethoxynaphthalene, 1,4-di Benzyloxynaphthalene,
1,2-diphenoxyethane, 1,2-bis (3-methylphenoxy) ethane, 1,2-bis (4-methylphenoxy) ethane, 1,4-diphenoxybutane, 1,4
-Diphenoxy-2-butene, 1,2-bis (4-methoxyphenylthio) ethane, dibenzoylmethane, 1,
4-diphenylthiobutane, 1,4-diphenylthio-
2-butene, 1,3-bis (2-vinyloxyethoxy) benzene, 1,4-bis (2-vinyloxyethoxy) benzene, p- (2-vinyloxyethoxy) biphenyl, p-aryloxybiphenyl, p -Propargyloxybiphenyl, dibenzoyloxymethane, dibenzoyloxypropane, dibenzyldisulfide,
1,1-diphenylethanol, 1,1-diphenylpropanol, p-benzyloxybenzyl alcohol,
1,3-phenoxy-2-propanol, N-octadecylcarbamoyl-p-methoxycarbonylbenzene,
N-octadecylcarbamoylbenzene, 1,2-bis (4-methoxyphenoxy) propane, 1,5-bis (4-methoxyphenoxy) -3-oxapentane, dibenzyl oxalate, bis (4-methylbenzyl) oxalate, Examples thereof include bis (4-chlorobenzyl oxalate), and generally, a white substance having a melting point of about 50 to 150 ° C. and having low water solubility is used.

In order to produce the heat-sensitive recording material of the present invention, a leuco dye, a color developer and a binder are added to a heat-sensitive color developing layer coating solution to which other auxiliaries are added. Then, the pressure-sensitive adhesive coating liquid and the barrier layer coating liquid may be sequentially applied and dried on the back surface thereof. As the binder in this case, various conventional binders can be used in appropriate amounts, and specific examples thereof include the following. Polyvinyl alcohol, starch and its derivatives, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylamide / acrylic ester copolymer, acrylamide / acrylic ester / methacrylic Acid terpolymer, styrene / maleic anhydride copolymer alkali salt, isobutylene acid / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate,
In addition to water-soluble polymers such as gelatin and casein, emulsions such as polyvinyl acetate, polyurethane, polyacrylic acid ester, polymethacrylic acid ester, vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer and styrene / Latex of butadiene / acrylic copolymers, etc.

When a heat-sensitive recording material is obtained according to the present invention, if necessary, an additive component commonly used in this kind of heat-sensitive recording material, for example, a filler, a surfactant, a lubricant, a pressure color-developing preventing agent or the like is used in combination. be able to. In this case, as a filler,
For example, calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate,
In addition to clay, kaolin, talc, inorganic fine powder such as surface-treated calcium and silica, organic fine powder such as urea-formalin resin, styrene / methacrylic acid copolymer, polystyrene resin, vinylidene chloride resin, etc. Can be mentioned. Examples of the lubricant include higher fatty acids and metal salts thereof, higher fatty acid amides, higher fatty acid esters, various waxes of animal, vegetable, mineral or petroleum type and the like. Further, in the present invention, an overcoat layer containing a water-soluble polymer as a main component can be provided on the thermosensitive coloring layer, if necessary. Specific examples of the water-soluble polymer in this case include those exemplified as the water-soluble polymer binder in relation to the thermosensitive color developing layer. Further, the water-soluble polymer can be used together with a conventional water-proofing agent for making it water-proof, and specific examples of the water-proofing agent include, for example,
Formaldehyde, glyoxal, chrome alum, melamine, melamine-formaldehyde resin, polyamide resin, polyamide-epichlorohydrin resin and the like can be mentioned. Further, the overcoat layer may optionally contain a conventional auxiliary additive component, for example, a filler, a heat-soluble substance (lubricant), a surfactant and the like. Specific examples of the filler and the heat-soluble substance are , Those exemplified in connection with the thermosensitive coloring layer. Furthermore, an under layer can be provided between the support and the thermosensitive coloring layer, if necessary.

[0014]

EFFECT OF THE INVENTION The heat-sensitive recording label of the present invention is a heat-sensitive recording label which has excellent adhesive properties to PVC wrap and does not require release paper.

[0015]

Next, the present invention will be described in more detail with reference to examples. All parts and% shown below are based on weight.

Example 1 [Solution A] 3-dibutylamino-6-methyl-7-anilinofluorane 20 parts 10% aqueous solution of polyvinyl alcohol 20 parts water 60 parts [Solution B] 4-isopropoxy-4'- Hydroxydiphenyl sulfone 10 parts 10% aqueous solution of polyvinyl alcohol 25 parts calcium carbonate 15 parts water 50 parts Mixtures of the above compositions each having an average particle size of 1.
[Solution A] and [Solution B] were prepared by dispersing with a sand mill so as to have a particle size of 5 μ or more and 2.5 μ or more. [Liquid C] Micro hollow particle dispersion (copolymer resin mainly composed of styrene-acryl) 33 parts (solid content concentration 27.5%, average particle diameter 1 μm, hollow ratio 50%) Styrene / Batagen copolymer latex 10 Parts (solid content concentration 47.5%) water 55 parts A mixture of the above composition is stirred and dispersed to prepare an undercoat liquid, which is a commercially available high-quality paper (basis weight 52 g / m 2).
^The undercoat paper was obtained by coating and drying on the surface of ² ) so that the weight after drying was 5 g / m ² . Next, the above [liquid A] 1
Parts and [B liquid] 10 parts to prepare a thermosensitive color forming layer forming liquid,
This was coated and dried on the surface of the above-mentioned undercoat paper so that the amount of dye adhering after drying was 0.5 g / m ^2, and a thermosensitive coloring layer was provided. [Solution D] Zinc stearate 20 parts Methylcellulose 5% aqueous solution 20 parts Water 60 parts [Solution E] Polyvinyl alcohol 10% aqueous solution 20 parts Silica 1.5 parts Polyamide epichlorohydrin 12.5% aqueous solution 6.5 parts Water 15 parts Next In addition, 45 parts of [solution D], 0.7 part of solution E and 1 part of water
1.3 parts were mixed and dispersed by stirring to prepare an overcoat liquid, which was coated and dried on the thermosensitive color developing layer to 0.35 g / m ² to form an overcoat layer. [Liquid F] Silica 10 parts 10% aqueous solution of polyvinyl alcohol 10 parts Water 10 parts Next, after stirring and dispersing the mixture comprising the above composition to prepare a backcoat liquid, the weight of the backside of the thermosensitive coloring layer after drying is A back coat layer is provided by coating and drying so that the coating amount becomes 2.5 g / m ^2, and the surface smoothness of the thermosensitive coloring layer is 500 to
The surface of the layer was calendered for 700 seconds to obtain a thermal recording paper. Next, an acrylic ester copolymer emulsion 54 was used as a pressure-sensitive adhesive on the back surface of the thermosensitive recording paper.
% Liquid (manufactured by Kanebo NSC) has a weight of 15 g / m after drying.
^A pressure-sensitive adhesive layer is formed by coating and drying so as to have a thickness of ^2, and a 58% aqueous solution of delayed tack paste is further provided on the pressure-sensitive adhesive layer as a barrier layer that develops tackiness by heat (Resitex: DT-
200) was dried and then coated and dried so that the weight became 12 g / m ^2, and a barrier layer was provided to obtain a label for heat-sensitive recording of the present invention.

Example 2 A thermosensitive recording label of the present invention was obtained in the same manner as in Example 1 except that the pressure sensitive adhesive was 15 g / m ² and the delayed tack glue was 8 g / m ² . .

Example 3 A thermosensitive recording label of the present invention was obtained in the same manner as in Example 1 except that the pressure sensitive adhesive was 18 g / m ² and the delayed tack glue was 2 g / m ² . .

Comparative Example 1 A thermosensitive recording label was prepared in the same manner as in Example 1 except that the pressure sensitive adhesive was not applied and only the delayed tack glue was applied so that the weight after drying was 20 g / m ^2. Got

The heat-sensitive recording labels of Examples 1 and 2 of the present invention and the heat-sensitive recording label of Comparative Example 1 which did not use the release paper obtained above were placed in a thermostatic bath at 100 ° C. for 20 seconds to be activated, It was pasted on a PVC wrap and pressure-bonded with a pressure roller having a weight of 5 kg. Further, the label for heat-sensitive recording of Example 3 of the present invention was irradiated with light at a speed of 2 inches / second with a pressure-sensitive adhesive side being a light source side through a PET film using 3M TRSNSPARENCYMAKER, and then immediately peeled off from the PET film and PVC wrapped. It was stuck to and was pressure-bonded with a pressure roller having a weight of 5 kg. These are cut to a width of 40 mm and the surface is well polished, and the PET film surface is attached to a stainless steel plate having a thickness of 0.5 mm with a double-sided tape. A desktop precision autograph (Shimadzu AGS-
50A) with a peel angle of 180 degrees and a peel speed of 300 mm
The load when peeled off continuously under the condition of / min was expressed as the peel strength (g / 40 mm), and the results immediately after the pasting and after the lapse of time are shown in Table 1.

[Table 1] Further, the thermosensitive coloring layer side of the thermosensitive recording label of the present invention was printed with a head temperature of 100 to 150 ° C., a crimping time of 1 second, and a crimping pressure of 2 kg / cm ² with a thermal gradient tester manufactured by Toyo Seiki Co., Ltd. A colored image was obtained. As is clear from the results of Table 1, the heat-sensitive recording label of the present invention is a heat-sensitive recording label that does not require a release paper that has sufficient adhesive strength to PVC wrap and has almost no adhesive strength over time. On the other hand, the label of Comparative Example 1 has an insufficient adhesive strength to the PVC wrap, and the adhesive strength is largely decreased with time, which clearly shows that the heat-sensitive recording label of the present invention is excellent.

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Claims (3)

[Claims] 1. A thermosensitive coloring layer containing a colorless or light-colored leuco dye and a color developer as main components is provided on the surface of a support, and a pressure-sensitive adhesive layer and a light- or heat-activated layer are provided on the back surface of the support. A heat-sensitive recording material, characterized in that barrier layers exhibiting tackiness are sequentially provided. 2. The dry weight of the barrier layer is 10 g / m.
The heat-sensitive recording material according to claim 1, which is ² or less. 3. The heat-sensitive recording material according to claim 1, wherein the ratio of the dry weight of the pressure-sensitive adhesive layer to the barrier layer is 2: 1 or less.