JP4794959B2 - Heat sensitive adhesive and heat sensitive adhesive material - Google Patents

Description

  The present invention relates to a heat-sensitive pressure-sensitive adhesive and a heat-sensitive pressure-sensitive adhesive material that are non-tacky at normal temperature but exhibit tackiness upon heating and that remain tacky even after the tackiness is developed.

  In recent years, adhesive materials for labels have been used as labels for logistics labels, price display labels, product display (barcode) labels, quality display labels, weighing display labels, advertising labels (stickers), etc. That is increasing. There are various recording methods such as an inkjet recording method, a thermal recording method, and a pressure sensitive recording method. Conventionally, a general pressure-sensitive adhesive sheet with a configuration in which a pressure-sensitive adhesive layer and release paper are laminated on the opposite side of the label's information recording surface can be simply attached by simply peeling off the release paper at the time of bonding. Widely used because it can. However, the adhesive material having a general configuration is used by peeling the release paper, but the peeled release paper is hardly collected and reused, and is almost always disposed of. Therefore, in recent years, a heat-sensitive adhesive material that does not exhibit adhesiveness at room temperature and does not require a release paper has attracted attention.

  The heat-sensitive adhesive is basically composed of a thermoplastic resin and a solid plasticizer as described in "Adhesion Handbook" 12th edition, 1980, published by Kobunshi Shuppankai, pages 131-135. And a tackifier if necessary. Thermoplastic resins impart adhesive strength and adhesive strength, and hot-melt materials are solid at room temperature (24 ° C), so they do not impart plasticity to resins, but melt by heating to swell the resin. Alternatively, it is softened to develop adhesiveness. The tackifier also works to improve the tackiness. Since the hot-melt material in the heat-sensitive adhesive is slowly crystallized after being melted by heating, the adhesiveness is maintained for a long time even after the heat source is removed. However, the conventional heat-sensitive adhesive has a problem that the adhesive strength after the development of adhesiveness decreases with time.

  In order to solve such a problem, for example, in JP-A-6-57226 (Patent Document 1) and JP-A-6-57233 (Patent Document 2), the glass transition point is 0 as a thermoplastic resin. It has been proposed to use an ethylene-vinyl acetate copolymer having a glass transition temperature of -5 ° C or higher, or a thermoplastic resin having a glass transition point of -5 ° C or higher (excluding an ethylene-vinyl acetate copolymer). However, although the adhesive strength to a stainless steel plate or the like has a relatively good result, the adhesive strength to a vinyl chloride wrap, a polyolefin wrap, or the like has not yet reached a practical level. The use of the heat-sensitive adhesive is not particularly limited, but for example, a pressure-sensitive adhesive material in which a layer made of a heat-sensitive adhesive is provided on one side of the substrate, and further, heat-sensitive color development on the other side of the substrate in addition to the heat-sensitive adhesive layer A heat-sensitive adhesive material provided with a layer can be mentioned. These are expected to be used for so-called food POS, in which various food products are packaged in wraps and pasted on the wraps. However, conventional heat-sensitive adhesives have insufficient adhesion to vinyl chloride wrap, polyolefin wrap, and the like, which hinders the practical application of heat-sensitive adhesive materials themselves.

  Japanese Patent Application Laid-Open No. 9-265260 (Patent Document 3) discloses a heat-sensitive adhesive material in which an undercoat layer containing non-foamed hollow particles is provided between a base material and a heat-sensitive color developing layer. A heat-sensitive adhesive using dicyclohexyl acid as a solid plasticizer has been proposed. Since this thermosensitive adhesive material is provided with an undercoat layer, it is at a level almost satisfactory in terms of improving the thermal sensitivity of the thermosensitive coloring layer and preventing the background coloring of the thermosensitive coloring layer that occurs during thermal activation. Regarding the blocking property that occurs when the two layers are superposed, they occur at about 40 ° C. and have not reached the practical level.

  Conventional techniques using an ester compound as a solid plasticizer are disclosed in JP-A-8-253747 (Patent Document 4), JP-A-8-302302 (Patent Document 5), and JP-A-2000-191922 (Patent Document 6). However, unlike the present invention, since only a monoester compound or a diester compound is used, recrystallization after thermal activation is described. However, there was a problem that the adhesive strength after the onset of adhesiveness decreased with time.

  Further, in Patent Document 6, as a solid plasticizer, (A) hydroquinones or resorcinols, or catechols and (B) a diester compound of an organic monobasic acid (typically, the diester compound of the present invention is listed in the text). However, unlike the present invention, there is no description of an example in which it is used in combination with at least one compound selected from benzotriazole compounds and phosphine compounds. Since the compound has a relatively high hydrophilicity, the blocking resistance when stored in a high temperature and high humidity environment has not reached a practical level.

  Japanese Patent Laid-Open No. 2002-155263 (Patent Document 8) describes the use of a benzoic acid triester or tetraester of benzoic acid and trifunctional or higher alcohol as a solid plasticizer. Since it has a large number of benzene rings, the compatibility with the thermoplastic resin was lowered, and in particular, the initial adhesive strength and time-dependent adhesiveness to cardboard did not reach practical levels.

  Japanese Patent Application Laid-Open No. 9-67551 (Patent Document 9) describes the use of dicyclohexyl phthalate and a carboxylic acid ester having a higher melting point as a solid plasticizer. Although dimethyl terephthalate having the same molecular weight and different only in the atomic arrangement of the ester structure (—COO—) is used, dimethyl terephthalate has a relatively high melting point (141-142 ° C.), and therefore the thermal sensitivity after thermal activation. The softness of the pressure-sensitive adhesive layer was insufficient, and in particular, the initial adhesive strength and time-dependent adhesiveness to cardboard at a temperature lower than room temperature did not reach a practical level.

  Further, JP-A-2004-114559 (Patent Document 10) discloses (i) phosphate esters (ii) phthalate esters (iii) hindered phenol compounds (iv) triazole compounds, and (v) aromatics. It is described that a solid plasticizer composed of at least two compounds selected from the group consisting of polyesters of polyols and organic acids is used. Particularly preferred solid plasticizers are (i) phosphate esters. (Ii) Phthalates (iii) It is composed of a combination of compounds contained in at least two compound groups among the four compound groups of hindered phenol compounds, and is mentioned in the examples. Combinations of solid plasticizers are limited to the above (i) to (iii).

  Thus, in these conventional known documents, as in the present invention, what constitutes a solid plasticizer with a combination of at least one compound selected from benzotriazole compounds and phosphine compounds and a diester compound is described. However, those described in these publicly known documents are insufficient in the softness of the heat-sensitive adhesive layer after thermal activation, so that the initial adhesive strength and the temporal adhesiveness with respect to cardboard at a temperature lower than room temperature reach practical levels. It was not.

JP-A-6-57226 JP-A-6-57233 JP-A-9-265260 JP-A-8-253747 JP-A-8-302302 JP 2000-191922 A JP 2002-88678 A JP 2002-155263 A Japanese Patent Laid-Open No. 9-67551 JP 2004-114559 A

  The present invention overcomes the disadvantages found in conventional heat-sensitive adhesives, and provides a heat-sensitive adhesive and a heat-sensitive adhesive material excellent in adhesive strength against cardboard and blocking resistance. An object of the present invention is to provide a heat-sensitive adhesive and a heat-sensitive adhesive material having excellent initial adhesive strength to cardboard.

As a result of intensive studies in order to solve the above problems, the present inventors have shown at least one compound selected from benzotriazole compounds and phosphine compounds as a solid plasticizer and the following structural formula (I). The present inventors have found that the above problem can be solved by using a combination of diester compounds, and have completed the present invention based on this finding.
That is, the said subject is solved by (1)-(13) of this invention.
(1) “Adhesive component composed of thermoplastic resin and heat-sensitive adhesive mainly composed of solid plasticizer, wherein the solid plasticizer is at least one compound selected from benzotriazole compounds and phosphine compounds and the following structural formula A heat-sensitive adhesive comprising a combination with a diester compound represented by (I).

（２）「前記ベンゾトリアゾール系化合物が、下記構造式（II）で表わされる化合物であることを特徴とする前記（１）に記載の感熱性粘着剤。

(2) The heat-sensitive adhesive according to (1), wherein the benzotriazole-based compound is a compound represented by the following structural formula (II).

（３）「前記ホスフィン化合物が、下記構造式（III）で表わされる化合物であることを特徴とする前記（１）又は（２）に記載の感熱性粘着剤。

(3) “The heat-sensitive adhesive according to (1) or (2), wherein the phosphine compound is a compound represented by the following structural formula (III):

（４）「前記ベンゾトリアゾール系化合物が熱可塑性樹脂（粘着成分）１００重量部に対し５０〜５００重量部含有することを特徴とする前記（１）〜（３）のいずれかに記載の感熱性粘着剤」；
（５）「前記ホスフィン化合物が熱可塑性樹脂（粘着成分）１００重量部に対し５０〜５００重量部含有することを特徴とする前記（１）〜（４）のいずれかに記載の感熱性粘着剤」；
（６）「前記ジエステル化合物が熱可塑性樹脂（粘着成分）１００重量部に対し１０〜２００重量部含有することを特徴とする前記（１）〜（５）のいずれかに記載の感熱性粘着剤」；
（７）「該感熱性粘着剤中にさらに粘着付与剤を含有させることを特徴とする前記（１）〜（６）のいずれかに記載の感熱性粘着剤」；
（８）「前記（１）〜（７）のいずれかに記載の感熱性粘着剤からなる層を基材の片面に設けてなることを特徴とする感熱性粘着材料」；
（９）「該感熱性粘着剤層と基材との間に、微小中空粒子とバインダーを主成分とする中間層を設けてなることを特徴とする前記（８）に記載の感熱性粘着材料」；
（１０）「基材における感熱性粘着剤層とは反対側の面に、記録層を設けてなることを特徴とする前記（８）又は（９）に記載の感熱性粘着材料」；
（１１）「前記記録層が、感熱記録層、インクジェット記録層、熱転写用インク受容層、及び電子写真記録層のいずれかであることを特徴とする前記（１０）に記載の感熱性粘着材料」；
（１２）「前記感熱記録層が、少なくともロイコ染料と顕色剤を含む感熱記録層であることを特徴とする前記（１１）に記載の感熱性粘着材料」；
（１３）「ラベル状、シート状、及びロール状のいずれかであることを特徴とする前記（８）〜（１２）のいずれかに記載の感熱性粘着材料」。

(4) The heat-sensitive property according to any one of (1) to (3), wherein the benzotriazole-based compound is contained in an amount of 50 to 500 parts by weight with respect to 100 parts by weight of the thermoplastic resin (adhesive component). Adhesive ";
(5) The heat-sensitive adhesive according to any one of (1) to (4), wherein the phosphine compound is contained in an amount of 50 to 500 parts by weight with respect to 100 parts by weight of a thermoplastic resin (adhesive component). ";
(6) The heat-sensitive adhesive according to any one of (1) to (5), wherein the diester compound is contained in an amount of 10 to 200 parts by weight per 100 parts by weight of the thermoplastic resin (adhesive component). ";
(7) “The heat-sensitive adhesive according to any one of (1) to (6), wherein a tackifier is further contained in the heat-sensitive adhesive”;
(8) “Thermosensitive adhesive material, wherein a layer made of the thermosensitive adhesive according to any one of (1) to (7) is provided on one side of a substrate”;
(9) “The heat-sensitive adhesive material according to (8), wherein an intermediate layer mainly comprising fine hollow particles and a binder is provided between the heat-sensitive adhesive layer and the substrate. ";
(10) “The heat-sensitive adhesive material according to (8) or (9) above, wherein a recording layer is provided on the surface of the substrate opposite to the heat-sensitive adhesive layer”;
(11) “The thermosensitive adhesive material according to (10), wherein the recording layer is any one of a thermosensitive recording layer, an inkjet recording layer, a thermal transfer ink receiving layer, and an electrophotographic recording layer”. ;
(12) “The thermosensitive adhesive material according to (11), wherein the thermosensitive recording layer is a thermosensitive recording layer containing at least a leuco dye and a developer”;
(13) “The heat-sensitive adhesive material according to any one of (8) to (12), which is any one of a label shape, a sheet shape, and a roll shape”.

  According to the present invention, by using a specific compound in combination as a solid reversible agent, the disadvantages of conventional heat-sensitive adhesives are overcome, and in particular, the initial adhesive force to cardboard at a temperature lower than room temperature is improved. A heat-sensitive adhesive material such as a heat-sensitive adhesive and a heat-sensitive adhesive label having excellent blocking resistance is provided.

The heat-sensitive adhesive of the present invention generally has a thermoplastic resin, which is a main component (adhesive component) that imparts adhesive strength and adhesive strength by heating, and melts by heating to cause the adhesive component to exhibit adhesiveness. It is mainly composed of a benzotriazole compound and / or a phosphine compound and a diester compound which are specific solid reversible agent components.
The heat-sensitive adhesive of the present invention is a heat-sensitive adhesive mainly composed of a thermoplastic resin and a solid plasticizer, wherein the solid plasticizer is at least one compound selected from benzotriazole and a phosphine compound, and the following structure: By being comprised from the diester compound represented by Formula (I), the initial adhesive force in a low-temperature environment from room temperature with respect to each to-be-adhered body, especially cardboard is strong, and blocking resistance becomes favorable.

  Benzotriazole compounds preferably used in the heat-sensitive adhesive of the present invention include 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2 -Hydroxy-5-t-octylphenyl) -2H-benzotriazole, 2- (3,5-di-t-pentyl-2-hydroxyphenyl) -2H-benzotriazole, 5-chloro-2- (3,5 -Di-t-butyl-2-hydroxyphenyl) -2H-benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole and the like.

  In particular, among the above benzotriazole-based compounds, compounds represented by the following formula (II) are preferable, and when these compounds are used, the heat-sensitive adhesive layer after thermal activation becomes very soft. The initial adhesive strength of the drastically improved.

  Examples of the phosphine compound preferably used in the heat-sensitive adhesive of the present invention include tris (pt-butoxyphenyl) phosphine, tris (2,4-dimethylphenyl) phosphine, tris (2,5-dimethylphenyl) phosphine. , Tris (3,5-dimethylphenyl) phosphine, tris (o-methylphenyl) phosphine, tris (p-methylphenyl) phosphine, tris (p-methoxyphenyl) phosphine and the like.

  In particular, among the above phosphine compounds, compounds represented by the following formula (III) are preferable, and when these compounds are used, the heat-sensitive adhesive layer after thermal activation becomes very soft, so that the initial temperature is particularly low at room temperature. Adhesive strength is dramatically improved.

  In the heat-sensitive adhesive of the present invention, the content of the benzotriazole compound and the phosphine compound in the solid plasticizer in the heat-sensitive adhesive is 50 to 500 parts by weight with respect to 100 parts by weight of the thermoplastic resin as the pressure-sensitive adhesive component. Is more preferable, and it is more preferably used in the range of 100 to 400 parts by weight. When the content of the benzotriazole-based compound and the phosphine compound exceeds 500 parts by weight with respect to 100 parts by weight of the thermoplastic resin as the adhesive component, the adhesive strength may be lowered. Further, when combined with a low Tg resin, if the content of the benzotriazole compound and the phosphine compound is less than 50 parts by weight with respect to 100 parts by weight of the thermoplastic resin as the adhesive component, the adhesive strength is increased at a normal storage environment temperature. It causes storage problems such as expression.

  Further, in the heat-sensitive adhesive of the present invention, the content of the diester compound in the solid plasticizer in the heat-sensitive adhesive is preferably 10 to 200 parts by weight with respect to 100 parts by weight of the thermoplastic resin of the pressure-sensitive adhesive component. More preferably, it is used in the range of 20 to 100 parts by weight. When the content of the diester compound is less than 20 parts by weight with respect to 100 parts by weight of the thermoplastic resin as the adhesive component, the adhesive force may be lowered. Further, when combined with a low Tg resin, if the content of the diester compound exceeds 200 parts by weight with respect to 100 parts by weight of the thermoplastic resin of the adhesive component, adhesive strength is exhibited at a temperature in a normal storage environment. Problems with storage occur.

  The thermoplastic resin that is preferably used in combination with the heat-sensitive adhesive of the present invention includes natural rubber latex, natural rubber latex, polyvinyl acetate, acrylic acid ester copolymer, methacrylic acid ester copolymer, which are graft copolymerized with vinyl monomers. Polymer, acrylic ester-methacrylic ester copolymer, synthetic rubber, vinyl acetate-acrylic acid 2-ethylhexyl copolymer, vinyl acetate-ethylene copolymer, vinyl pyrrolidone-styrene copolymer, vinyl pyrrolidone-acrylic ester Examples thereof include polymer resins such as copolymers and styrene-acrylic copolymers, but are not limited thereto.

  The content of the thermoplastic resin in the heat-sensitive adhesive is preferably 10 to 60% by weight, more preferably 15 to 50% by weight. When the content of the thermoplastic resin is less than 10% by weight or more than 60% by weight, both are undesirable because the adhesive strength is lowered. On the other hand, when the content of the low Tg resin exceeds 60% by weight, there are problems in storage such as an adhesive force developed at a normal storage environment temperature.

  Furthermore, in order to improve the adhesive strength of heat-sensitive adhesives, rosin derivatives (rosin, polymerized rosin, hydrogenated rosin and their glycerin, pentaerythritol, etc.) that are tackifiers used in general adhesives for the above components Ester, resin acid dimer, etc.), terpene resin, petroleum resin, phenol resin and xylene resin can be used.

  Examples of tackifiers that are particularly preferably used in the heat-sensitive adhesive of the present invention include rosin derivatives (rosin, polymerized rosin, hydrogenated rosin and esters thereof with glycerin, pentaerythritol, etc., resin acid dimers, etc.), terpene resins (Terpene resin, aromatic modified terpene resin, terpene phenol resin, hydrogenated terpene resin). These tackifiers are compatible with the thermoplastic resin and the hot-melt material of the present invention, and the adhesive strength of the heat-sensitive adhesive is significantly improved. Moreover, the melting point or softening point of the tackifier in the heat-sensitive adhesive is preferably 80 ° C. or higher, more preferably 80 to 200 ° C. When the temperature is less than 80 ° C., storage defects (decrease in blocking resistance) occur at normal storage environment temperatures. Moreover, the content of the tackifier in the heat-sensitive adhesive is preferably 5 to 30% by weight, and more preferably 5 to 20% by weight. If it is less than 5% by weight, the adhesive strength is reduced, and if it exceeds 30% by weight, storage problems (decrease in blocking resistance) occur at temperatures in a normal storage environment.

  In the heat-sensitive adhesive of the present invention, in addition to the above components, in order to prevent blocking, inorganic substances such as titanium oxide, alumina, colloidal silica, kaolin, talc, stearic acid metal salts, paraffin, natural wax, synthetic wax, A natural oil and fat, an organic substance such as polystyrene powder, and a dispersant, an antifoaming agent, a thickener and the like can be used as necessary.

The heat-sensitive adhesive of the present invention can be used as a heat-sensitive adhesive material by providing it as a heat-sensitive adhesive layer on one side of a substrate.
By applying the heat-sensitive adhesive of the present invention to one surface of a substrate, a heat-sensitive adhesive material having strong adhesive strength against vinyl chloride wrap and polyolefin wrap, particularly cardboard, and good blocking resistance can be obtained.

  The heat-sensitive adhesive material of the present invention can be produced by providing the substrate with the heat-sensitive pressure-sensitive adhesive layer of the present invention by coating or printing. It must be dried at a temperature range where the material does not melt. As a means for drying, in addition to hot air drying, a drying method using a heat source using infrared rays, microwaves, and high frequencies can be used.

The coating amount of the heat-sensitive adhesive layer of the present invention, dry coating amount in the normal 2~35g / ^{m 2,} and preferably applied in the range of 5 to 25 g / ^{m 2.} When the coating amount of the heat-sensitive adhesive layer is less than 2 g / m ² , sufficient adhesion cannot be obtained when performing adhesion by heating. On the other hand, if it exceeds 35 g / m ² , the adhesion function is saturated, which is not economical.

  In the heat-sensitive adhesive material of the present invention, a recording layer can be provided on the surface of the substrate opposite to the heat-sensitive adhesive layer. Examples of the recording layer include a thermosensitive recording layer, an ink jet recording layer, a thermal transfer ink receiving layer, and an electrophotographic recording layer.

Hereinafter, a case where the recording layer is a thermosensitive recording layer will be described as a representative example.
In the heat-sensitive recording layer of the present invention, a heat-sensitive recording layer mainly composed of a leuco dye and a developer can be formed on the substrate. As the leuco dye used in the heat-sensitive recording layer of the present invention, a leuco dye known in this type of leuco recording material is generally applied. For example, triphenylmethane, fluorane, phenothiazine, auramine, spiropyran And leuco compounds of dyes such as indolinophthalide are preferably used.

  Specific examples of such leuco dyes include 3,3-bis (p-dimethylaminophenyl) phthalide and 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (also called crystal violet lactone). 3,3-bis (p-dimethylaminophenyl) -6-diethylaminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-chlorophthalide, 3,3-bis (p-dibutylaminophenyl) phthalide 3-cyclohexylamino-6-chlorofluorane, 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- (Np-tolyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2- {N- (3'- Trifluoromethylphenyl) amino} -6-diethylaminofluorane, 3-diethylamino-6-methyl-7- (m-trichloromethylanilino) fluorane, 3-diethylamino-7- (o-chloroanilino) fluorane, 3-dibutyl Amino-7- (o-chloroanilino) fluorane, 3-N-methyl-N-amylamino-6-methyl-7-anilinofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-ani Linofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3- (N, N-diethylamino) -5-methyl-7- N, N-dibenzylamino) fluorane, benzoylleucomethylene blue, 6'-chloro-8'-methoxy-benzoindolino-pyrospirane, 6'-bromo-3'-methoxy-benzoindolino-pyrospirane, 3- (2 '-Hydroxy-4'-dimethylaminophenyl) -3- (2'-methoxy-5'-chlorophenyl) phthalide, 3- (2'-hydroxy-4'-dimethylaminophenyl) -3- (2'- Methoxy-5'-nitrophenyl) phthalide, 3- (2'-hydroxy-4'-diethylaminophenyl) -3- (2'-methoxy-5'-methylphenyl) phthalide, 3-diethylamino-6-methyl-7 -(2 ', 4'-dimethylanilino) fluorane, 3- (2'-methoxy-4'-dimethylaminophenyl) -3- (2'-hydroxy-4'-chloro-5'-methylphenyl) phthalide, 3-morpholino-7- (N-propyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7-trifluoromethylanilinofur Oran, 3-diethylamino-5-chloro-7- (N-benzyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7- (di-p-chlorophenyl) methylaminofluorane, 3-diethylamino-5- Chlor-7- (α-phenylethylamino) fluorane, 3- (N-ethyl-p-toluidino) -7- (α-phenylethylamino) fluorane, 3-diethylamino-7- (o-methoxycarbonylphenylamino) Fluorane, 3-diethylamino-5-methyl-7- (α-phenylethylamino) fluorane 3-diethylamino-7-piperidinofluorane, 2-chloro-3- (N-methyltoluidino) -7- (pn-butylanilino) fluorane, 3- (N-benzyl-N-cyclohexylamino) -5 6-benzo-7-α-naphthylamino-4'-bromofluorane, 3-diethylamino-6-methyl-7-mesitidino-4 ', 5'-benzofluorane, 3-diethylamino-6-methyl-7- (2 ', 4'-dimethylanilino) fluorane, 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- (4'-dimethyl) Ruamino-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-dimethyl) Ruaminostyryl) -1-naphthalenesulfonylmethane, 3- (N-methyl-N-propylamino) -6-methyl-7-anilidefluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3 , 6-Bis (dimethylamino) fluorane spiro (9,3 ')-6'-dimethylaminophthalide, 3-diethylamino-6-chloro-7-anilinofluorane, 3-N-ethyl-N- ( 2-Ethoxypropyl) amino-6-methyl-7-anilinofluorane, 3-N-ethyl-N-tetrahydrofurfurylamino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl- 7-mesitidino-4 ', 5'-benzofluorane, 3-N-methyl-N-isobutyl-6-methyl-7-anilinofluorane, 3-N-ethyl It can be mentioned N- isoamyl-6-methyl-7-anilinofluoran, and the like.

  In the heat-sensitive recording layer of the present invention, various electron-accepting compounds such as phenolic compounds, thiophenolic compounds, thiourea derivatives, organic acids and metal salts thereof can be applied as color developers. it can. Specific examples thereof include 4,4'-isopropylidene bisphenol, 3,4'-isopropylidene bisphenol, 4,4'-isopropylidene bis (o-methylphenol), 4,4'-secondary butylidene bisphenol, 4 , 4'-isopropylidenebis (o-tertiarybutylphenol), 4,4'-cyclohexylidenediphenol, 4,4'-isopropylidenebis (2-chlorophenol), 2,2'-methylenebis (4-methyl) -6-tertiarybutylphenol), 2,2'-methylenebis (4-ethyl-6-tertiarybutylphenol), 4,4'-butylidenebis (6-tertiarybutyl-2-methyl) phenol, 1,1,3 -Tris (2-methyl-4-hydroxy-5-tertiary butylphenol L) butane, 1,1,3-tris (2-methyl-4-hydroxy-5-cyclohexylphenyl) butane, 4,4'-thiobis (6-tertiarybutyl-2-methyl) phenol, 4,4 ' -Diphenol sulfone, 4,2'-diphenol sulfone, 4-isopropoxy-4'-hydroxydiphenyl sulfone, 4-benzyloxy-4'-hydroxydiphenyl sulfone, 4,4'-diphenol sulfoxide, P-hydroxybenzoic acid Isopropyl acid, benzyl P-hydroxybenzoate, benzyl protocatechuate, stearyl gallate, lauryl gallate, octyl gallate, 1,7-bis (4-hydroxyphenylthio) -3,5-dioxaheptane, 1,5 -Bis (4-hydroxyphenylthio) -3-oxaheptane, 1,3 Bis (4-hydroxyphenylthio) -propane, 2,2'-methylenebis (4-ethyl-6-tertiarybutylphenol), 1,3-bis (4-hydroxyphenylthio) -2-hydroxypropane, N, N '-Diphenylthiourea, N, N'-di (m-chlorophenyl) thiourea, salicylanilide, 5-chloro-salicylanilide, salicyl-o-chloroanilide, 2-hydroxy-3-naphthoic acid, zinc thiocyanate Antipyrine complex, zinc salt of 2-acetyloxy-3-naphthoic acid, 2-hydroxy-1-naphthoic acid, 1-hydroxy-2-naphthoic acid, zinc of hydroxynaphthoic acid, metal salts such as aluminum and calcium, bis- (4-Hydroxyphenyl) acetic acid methyl ester, bis- (4-hydroxyphenyl) acetic acid Benzyl ester, 4- {β- (p-methoxyphenoxy) ethoxy} salicylic acid, 1,3-bis (4-hydroxycumyl) benzene, 1,4-bis (4-hydroxycumyl) benzene, 2,4 ′ -Diphenolsulfone, 3,3'-diallyl-4,4'-diphenolsulfone, antipyrine complex of α, α-bis (4-hydroxyphenyl) -α-methyltoluenethiocyanate, tetrabromobisphenol A, tetra Examples include bromobisphenol S, 4,4'-thiobis (2-methylphenol), 3,4-hydroxy-4'-methyl-diphenylsulfone, 4,4'-thiobis (2-chlorophenol), and the like.

  In order to form the heat-sensitive recording layer of the present invention, a leuco dye and a developer may be bonded and supported on a substrate. In this case, various conventional binders can be used as appropriate. Examples of such binders include polyvinyl alcohol, starch and derivatives thereof, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, polyacrylic acid soda, polyvinylpyrrolidone, acrylamide / acrylic acid ester copolymer Water-soluble compounds such as acrylamide / acrylic acid ester / methacrylic acid terpolymers, styrene / maleic anhydride copolymer alkali salts, isobutylene / maleic anhydride copolymer alkali salts, polyacrylamide, sodium alginate, gelatin, casein, etc. In addition to functional polymers, polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic acid ester, polymethacrylic acid ester, polybutyl methacrylate, vinyl chloride / acetic acid Cycloalkenyl copolymer, ethylene / emulsion and styrene / butadiene copolymer vinyl acetate copolymer, it can be mentioned latices such as styrene / butadiene / acrylic copolymer.

  Further, when the heat-sensitive recording layer is formed according to the present invention, various heat-fusible substances can be used as fillers. Specific examples thereof include fatty acids such as stearic acid and behenic acid, fatty acid amides such as stearic acid amide and palmitic acid amide, and fatty acids such as zinc stearate, aluminum stearate, calcium stearate, zinc palmitate and zinc behenate. Metal salts, p-benzylbiphenyl, terphenyl, triphenylmethane, benzyl p-benzyloxybenzoate, β-benzyloxynaphthalene, β-naphthoic acid phenyl ester, 1-hydroxy-2-naphthoic acid phenyl ester, 1-hydroxy 2-naphthoic acid methyl ester, diphenyl carbonate, terephthalic acid dibenzyl ester, terephthalic acid dimethyl ester, 1,4-dimethoxynaphthalene, 1,4-diethoxynaphthalene, 1,4-dibenzyloxynaphthalene, 1, 2-bis (phenoxy) ethane, 1,2-bis (3-methylphenoxy) ethane, 1,2-bis (4-methylphenoxy) ethane, 1,4-bis (phenoxy) butane, 1,4-bis ( Phenoxy) -2-butene, 1,2-bis (4-methoxyphenylthio) ethane, dibenzoylmethane, 1,4-bis (phenylthio) butane, 1,4-bis (phenylthio) -2-butene, 1, 2-bis (4-methoxyphenylthio) ethane, 1,3-bis (2-vinyloxyethoxy) benzene, 1,4-bis (2-vinyloxyethoxy) benzene, p- (2-vinyloxyethoxy) biphenyl , P-aryloxybiphenyl, p-propargyloxybiphenyl, dibenzoyloxymethane, 1,3-dibenzoyloxypropane, dibenzyldi Rufide, 1,1-diphenylethanol, 1,1-diphenylpropanol, p- (benzyloxy) benzyl alcohol, 1,3-diphenoxy-2-propanol, N-octadecylcarbamoyl-p-methoxycarbonylbenzene, N-octadecylcarbamoyl Benzene, oxalic acid dibenzyl ester, 1,5-bis (p-methoxyphenyloxy) -3-oxapentane and the like can be mentioned.

  In the present invention, auxiliary additives commonly used in this type of heat-sensitive recording layer, such as surfactants and lubricants, can be used in combination as required. In this case, examples of the lubricant include higher fatty acids and metal salts thereof, higher fatty acid amides, higher fatty acid esters, animal, vegetable, mineral, and petroleum-based waxes.

  In the present invention, if necessary, for example, an undercoat layer is provided between the substrate and the heat-sensitive recording layer, or a water-soluble resin is used on the heat-sensitive recording layer for the purpose of improving image reliability. A protective layer having a main component can also be provided. In this case, as the components constituting these layers, the above-mentioned fillers, binders, thermofusible substances, surfactants and the like can be used. Furthermore, when the protective layer and the protective layer are not provided, a printed image can be formed directly on the heat-sensitive recording layer. For example, UV curable ink is used as the printing ink.

  The heat-sensitive recording layer of the present invention can be formed by a generally known method. For example, first, the leuco dye and the developer are separately pulverized and dispersed together with an aqueous binder solution by a dispersing machine such as a ball mill, an attritor, or a sand mill until the dispersed particle size becomes 1 to 3 μm, and a filler as required. A heat-sensitive recording layer can be formed by preparing a heat-sensitive recording layer coating solution by mixing with a thermofusible substance (sensitizer) dispersion and the like, and applying it to a substrate.

  By applying the heat-sensitive adhesive of the present invention on various substrates, a heat-sensitive adhesive material can be obtained. As described above, an intermediate layer is provided between the substrate and the heat-sensitive adhesive layer, or In the case of an adhesive material provided with a heat-sensitive recording layer, an undercoat layer can be provided between the substrate and the heat-sensitive recording layer. When providing these intermediate layer and / or undercoat layer, it is preferable that it is heat-insulating, and by providing such a layer, the thermal efficiency of the heat-sensitive adhesive layer during the heat-sensitive adhesive activity is improved, Further, the thermal sensitivity of the thermosensitive recording layer is improved, and the background coloration of the thermosensitive recording layer during thermal activation can be prevented, and the thermal energy during thermal activation of these layers can be utilized efficiently. Hereinafter, when the intermediate layer and / or the undercoat layer is heat insulating, it is referred to as a heat insulating layer. Examples of the heat insulating layer include a non-foaming heat insulating layer using fine hollow particles having a hollowness of about 30 to 95% or a porous pigment and a foaming heat insulating layer using a foaming filler.

The fine hollow particles having a hollowness of about 30 to 95%, which uses the thermoplastic resin used for the heat insulating layer as a soot, contain air or other gas inside, and are fine hollow particles already in a foamed state. The average particle diameter of the fine hollow particles is preferably 0.2 to 20 μm, more preferably 0.5 to 10 μm. When this average particle diameter (particle outer diameter) is smaller than 0.2 μm, it is difficult to technically make it hollow and the role of the heat insulating layer becomes insufficient. On the other hand, if it is larger than 20 μm, the smoothness of the surface after coating and drying is lowered, so that the application of the heat-sensitive adhesive layer and the heat-sensitive recording layer becomes non-uniform, and more than necessary to make it more uniform. A heat-sensitive adhesive or a coating solution for the heat-sensitive recording layer must be applied. Therefore, it is desirable that such a fine hollow particle distribution has a uniform distribution spectrum with a small variation and a particle diameter in the above range. Further, in the present invention, fine hollow particles having a hollowness of 30% or more can be preferably used, but those having a hollowness of 50% or more are more preferable. When the hollowness is less than 30%, the heat insulation is insufficient, so that heat energy is released to the outside through the base material, and the heat efficiency is deteriorated when the pressure-sensitive adhesive is activated or the heat-sensitive recording layer is colored. Absent.
The said hollowness here is ratio of the volume on the basis of the outer diameter of the hollow fine particles and the volume on the basis of the inner diameter.

As described above, the hollow microparticles used in the present invention are made of a thermoplastic resin, and the thermoplastic resin is preferably a copolymer resin mainly composed of vinylidene chloride and acrylonitrile.
In addition, a porous pigment may be used for the heat insulating layer of the present invention. Examples of the pigment include organic pigments such as urea formaldehyde resin and inorganic pigments such as shirasu earth, but are not necessarily limited thereto. . Furthermore, a foamable filler may be used for the heat insulating layer of the present invention. When the foamable filler is used, after the coating liquid for the heat insulating layer is applied to the substrate, the foamable filler in the coating liquid is foamed. You can do it.

In order to form the non-foaming heat insulating layer of the present invention, the above-mentioned fine hollow particles and porous pigment are dispersed in water together with a binder, and this is applied onto a substrate and dried. In this case, the coating amount of the fine hollow particles is at least 1 g per 1 m ² of the support, more preferably about 2 to 15 g. The amount of the binder resin used may be an amount sufficient to strongly bond the heat insulating layer to the substrate, and is usually 2 to 50% by weight based on the total amount of the fine hollow particles and the binder resin.

  The binder used when forming the non-foaming heat insulating layer is appropriately selected from conventionally known water-soluble polymers and / or aqueous polymer emulsions. Specific examples thereof include water-soluble polymers such as polyvinyl alcohol, starch and derivatives thereof, cellulose derivatives such as methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, and ethylcellulose, sodium polyacrylate, polyvinylpyrrolidone, acrylamide / acrylic acid. Ester copolymer, acrylamide / acrylic ester / methacrylic acid terpolymer, styrene / maleic anhydride copolymer alkali salt, isobutylene / maleic anhydride copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein, etc. Is mentioned. Examples of the aqueous polymer emulsion include latex such as styrene / butadiene copolymer, styrene / butadiene / acrylic copolymer, vinyl acetate resin, vinyl acetate / acrylic acid copolymer, and styrene / acrylic acid ester copolymer. And emulsions such as acrylic ester resins and polyurethane resins.

  The foamable filler used in the present invention is a hollow plastic filler containing a foaming agent of a low-boiling-point solvent inside with a thermoplastic resin as a base, and various types are applied. Is 2 to 50 μm in the unfoamed state, and 10 to 100 μm, preferably 10 to 50 μm in the foamed state. Examples of the thermoplastic resin used as the plastic filler include polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyacrylic acid ester, polyacrylonitrile, polybutadiene, and copolymers thereof. Further, as the foaming agent contained in the bag, propane, butane or a mixture thereof is generally used.

In order to form a foamable heat insulating layer on a base material, the foamable plastic filler described above is applied and dried on the base material together with a binder, and then a hot plate is adhered to the coated surface, and the plastic filler is heated and foamed. You can do it. The application amount of the plastic filler is preferably at least 1 g or more, more preferably about ² to 5 g as an unfoamed filler with respect to 1 m ² of the base material. Moreover, the usage-amount of a binder should just be an quantity which makes a foaming heat insulation layer bind | bond strongly with respect to a base material, Usually, it is 5-5 with respect to the total amount of an unfoamed filler and a binder. 50% by weight. The heating foaming temperature is a temperature at which the thermoplastic resin constituting the filler ridge is softened. The expansion ratio is usually 2 to 4 times, preferably about 2 to 3 times, and is appropriately selected so as to achieve the above foaming.

  As described above, the surface of the foamable heat insulating layer formed on the base material is considerably uneven, so that the flat surface is smoothed by calendering after the foamable heat insulating layer is formed (after heating and foaming). In addition, if necessary, one or more undercoat layers can be provided on the surface or the lower surface of the foamable heat insulating layer.

  In the heat insulating layer of the present invention, a filler, a heat-fusible substance (sensitizer), a surfactant, etc. are used in combination with the fine hollow particles, the porous pigment or the foamable filler and the binder as necessary. can do. In this case, examples of the filler include inorganic fine powders such as calcium carbonate, silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, barium sulfate, clay, talc, surface-treated calcium and silica, and the like. Organic fine powders such as urea-formalin resin, styrene / methacrylic acid copolymer, polystyrene resin, and the like. Examples of the heat fusible substance (sensitizer) include higher fatty acids or their In addition to 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-hexahydrophthalates, higher ketones, p -Benzylbiphenyl and other thermofusible organic compounds such as those having a melting point of about 50 to 200 ° C.

  In addition, the base material used in the present invention is not particularly limited, and is a high-quality paper, art paper, coated paper or the like, polyester film such as polyethylene terephthalate or polybutylene terephthalate other than paper, and cellulose derivative film such as cellulose triacetate. Polyolefin films such as polypropylene and polyethylene, polystyrene films, or films obtained by bonding them together can be used.

  Coating methods for providing the coating layer include blade coating method, gravure coating method, gravure offset coating method, bar coating method, roll coating method, knife coating method, air knife coating method, comma coating method, U comma coating method, and AKKU. Known coating methods such as coating method, smoothing coating method, microgravure coating method, reverse roll coating method, four or five roll coating method, dip coating method, falling curtain coating method, slide coating method, die coating method, etc. Is available.

  The heat-sensitive adhesive material of the present invention can be suitably used by being cut before or after thermal activation (heating) of the heat-sensitive adhesive layer. In this case, A cut may be formed in advance. In these cases, the heat-sensitive adhesive material is advantageous in that it can be suitably used for various uses such as labels and tags.

  There is no restriction | limiting in particular as a shape of the heat sensitive adhesive material of this invention, A label form, a sheet form, a roll form, etc. are mentioned suitably.

  The adherend to which the heat-sensitive adhesive material of the present invention is affixed is not particularly limited, and its size, shape, structure, material, and the like can be appropriately selected according to the purpose. For example, polyolefins such as polyethylene and polypropylene, acrylic resins, polyethylene terephthalate (PET), resin plates such as polystyrene and nylon, metal plates such as SUS and aluminum, paper products such as envelopes and cardboard, polyolefin wraps, poly Preferable examples include vinyl chloride wraps and polyethylene non-woven fabrics (envelopes and the like).

  Among these, the cardboard is generally difficult to affix a heat-sensitive adhesive material, but in the case of the heat-sensitive adhesive material of the present invention, it is possible to develop a strong adhesive force over time. Is advantageous in that it can be firmly attached.

The method for thermally activating the heat-sensitive adhesive layer in the heat-sensitive adhesive material of the present invention is not particularly limited and may be appropriately selected depending on the intended purpose. For example, an activation method using hot air or a hot roll is used. Examples thereof include an activation method and an activation method using a thermal head.
Among these, an activation method using a thermal head is preferable. When the heat-sensitive adhesive material of the present invention has a heat-sensitive recording layer, recording on the heat-sensitive recording layer and heating-sensitive adhesive are performed by heating both surfaces of the heat-sensitive adhesive material using an existing heat-sensitive recording printer device. This is advantageous and particularly preferred in that the agent layer can be thermally activated.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In addition, all the parts and% shown below are based on weight.

Example 1
[Liquid A] Diester compound dispersion 30.0 parts of diester compound represented by the following formula (I)

ポリビニルアルコール（３０％水溶液） ５．０部
界面活性剤（アルキル−アリルスルホン酸塩） ０．１５部
水 ６４．８５部
上記組成からなる混合物を、平均粒径が１．０μｍとなるようにサンドミルを用いて分散して分散液〔Ａ液〕を得た。

Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts Sand mill so that the average particle diameter is 1.0 μm. To obtain a dispersion liquid [A liquid].

[B-1 solution] Benzotriazole-based compound dispersion 30.0 parts of benzotriazole-based compound represented by the following formula (IV)

ポリビニルアルコール（３０％水溶液） ５．０部
界面活性剤（アルキル−アリルスルホン酸塩） ０．１５部
水 ６４．８５部
上記組成からなる混合物を、平均粒径が１．０μｍとなるようにサンドミルを用いて分散して分散液〔Ｂ−１液〕を得た。

Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts Sand mill so that the average particle diameter is 1.0 μm. Was used for dispersion to obtain a dispersion [B-1 solution].

[C-1 liquid] heat sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 20 parts Benzotriazole-based compound dispersion [Liquid B-1] 100 parts Heat-sensitive adhesive dispersion [Liquid C-1] having the above composition of 80 g / m ² of single-side coated paper The back surface was coated and dried to a dry weight of 16 g / m ² to obtain a heat-sensitive adhesive sheet.

Example 2
In Example 1, the triazole compound represented by the above formula (IV) using [B-1 solution] in [C-1 solution] as [B-1 solution] is represented by the following formula (II). A heat-sensitive adhesive sheet was obtained in the same manner as in Example 1 except that [C-2 solution], which was changed to [B-2 solution], was changed to a triazole compound.

Example 3
In Example 1, except for using [C-3 solution] in which the benzotriazole compound dispersion [B-1 solution] in [C-1 solution] was changed to the following phosphine compound dispersion [P-1 solution]. Obtained a heat-sensitive adhesive sheet in the same manner as in Example 1.
[P-1 solution] Phosphine compound dispersion 30.00 parts of phosphine compound represented by the following formula (V)

ポリビニルアルコール（３０％水溶液） ５．０部
界面活性剤（アルキル−アリルスルホン酸塩） ０．１５部
水 ６４．８５部

Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts

Example 4
In Example 3, the phosphine compound represented by the above formula (V) using the [P-1 solution] in the [C-3 solution] as the [P-1 solution] is represented by the following formula (III). A heat-sensitive adhesive sheet was obtained in the same manner as in Example 3 except that [C-4 solution], which was changed to the compound [P-2 solution], was used.

Example 5
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-5 solution] having the following composition in Example 2.
[C-5 liquid] Thermosensitive adhesive liquid Methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 20 parts Benzotriazole compound dispersion [Liquid B-2] 17 parts

Example 6
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-6 solution] having the following composition in Example 2.
[C-6 liquid] Heat sensitive adhesive liquid Methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 20 parts Benzotriazole compound dispersion [Liquid B-2] 166 parts

Example 7
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-7 solution] having the following composition in Example 2.
[C-7 liquid] Thermosensitive adhesive liquid Methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, volatile content 50%)
Diester compound dispersion [Liquid A] 20 parts Benzotriazole compound dispersion [Liquid B-2] 10 parts

Example 8
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-8 solution] having the following composition in Example 2.
[C-8 liquid] Thermosensitive adhesive liquid Methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 20 parts Benzotriazole compound dispersion [Liquid B-2] 170 parts

Example 9
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 4 except that [C-4 solution] was changed to [C-9 solution] having the following composition in Example 4.
[C-9 liquid] heat sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [liquid A] 20 parts Phosphine compound dispersion [liquid P-2] 17 parts

Example 10
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 4 except that [C-4 solution] was changed to [C-10 solution] having the following composition in Example 4.
[C-10 liquid] heat sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [liquid A] 20 parts Phosphine compound dispersion [liquid P-2] 166 parts

Example 11
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 4 except that [C-4 solution] was changed to [C-11 solution] having the following composition in Example 4.
[C-11 liquid] heat-sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [liquid A] 20 parts Phosphine compound dispersion [liquid P-2] 10 parts

Example 12
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 4 except that [C-4 solution] was changed to [C-12 solution] having the following composition in Example 4.
[C-12 liquid] heat-sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [liquid A] 20 parts Phosphine compound dispersion [liquid P-2] 170 parts

Example 13
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-13 solution] having the following composition in Example 2.
[C-13 liquid] heat-sensitive adhesive liquid 20 parts of methyl methacrylate-butyl acrylate copolymer emulsion
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 4 parts Benzotriazole compound dispersion [Liquid B-2] 100 parts

Example 14
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-14 solution] having the following composition in Example 2.
[C-14 liquid] heat-sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [liquid A] 32 parts Benzotriazole compound dispersion [liquid B-2] 100 parts

Example 15
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-15 solution] having the following composition in Example 2.
[C-15 liquid] heat-sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 2 parts Benzotriazole compound dispersion [Liquid B-2] 100 parts

Example 16
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [C-2 solution] was changed to [C-16 solution] having the following composition in Example 2.
[C-16 liquid] heat-sensitive adhesive liquid methyl methacrylate-butyl acrylate copolymer emulsion 20 parts
(Tg-62 ° C, nonvolatile content 50%)
Diester compound dispersion [Liquid A] 70 parts Benzotriazole compound dispersion [Liquid B-2] 100 parts

Example 17
A heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that the following [D liquid] was used instead of [C-2 liquid] in Example 2.
[Liquid D] Heat-sensitive adhesive dispersion 20 parts of methyl methacrylate-butyl acrylate copolymer emulsion
(Tg-62 ° C, nonvolatile content 50%)
Diethyl ester compound dispersion [Liquid A] 20 parts Benzotriazole-based compound dispersion [Liquid B-2] 100 parts Polymerized rosin emulsion (softening point 145 ° C., nonvolatile content 50%) 6.5 parts

Example 18
[E solution] Intermediate layer coating solution Micro hollow particles (Acrylonitrile / Vinylidene chloride /
Methyl methacrylate copolymer) 14.6 parts (solid content concentration 41%, average particle size 3.6 μm, hollowness 90%)
2-ethylhexyl acrylate / methyl methacrylate /
Copolymer of styrene (Tg-65 ° C.) 21.7 parts (solid content concentration 55.4%, Showa Polymer)
63.7 parts of water The mixture having the above composition was stirred and dispersed to prepare an intermediate layer coating solution [solution E].
The above [E-solution] was applied to the back of 80 g / m ² single-sided coated paper and dried so that the weight would be 5 g / m ² to provide an intermediate layer. On this intermediate | middle layer, the heat-sensitive adhesive dispersion liquid [C-2 liquid] of the said Example 2 was apply | coated and dried so that it might become dry weight 16 / m < ² >, and the heat-sensitive adhesive label was obtained.

Example 19
[F liquid] Coating liquid for heat insulation layer Fine hollow particle dispersion vinylidene chloride /
Copolymer resin mainly composed of acrylonitrile (solid content concentration 32%, average particle size 3.0 μm, hollowness 92%) 30 parts Styrene / butadiene copolymer latex (Tg + 4 ° C.) 10 parts Water 60 parts The mixture was stirred and dispersed to prepare a heat insulating layer coating solution [F solution].

<Adjustment of thermal recording layer solution>
[G liquid] Color former dispersion liquid 3-di-n-butylamino-6-methyl-7-anilinofluorane 20 parts Polyvinyl alcohol (10% aqueous solution) 10 parts Water 70 parts

[Liquid H] Developer dispersion 4-isopropoxy-4'-hydroxydiphenylsulfone 10 parts Polyvinyl alcohol (10% aqueous solution) 25 parts Calcium carbonate 15 parts Water 50 parts

The mixture having the above composition is dispersed using a sand mill so that the average particle diameter is about 1.5 μm to prepare [Liquid G] and [Liquid H], and then [Liquid G]: [Liquid H] ] = 1: 8 was mixed and stirred to obtain a thermosensitive coloring layer solution [I solution].
The above [F liquid] was applied and dried on the surface of the base material so that the weight after drying was 4 g / m ² to provide a heat insulating layer.
On top of this, the above [I liquid] was applied and dried so as to have a weight of 5 g / m ² after drying to provide a thermosensitive coloring layer.

<Adjustment of protective layer solution>
[Primary dispersion for protective layer]
Aluminum hydroxide 20 parts 10% PVA aqueous solution 20 parts Water 40 parts Subsequently, a protective layer solution having the following composition was prepared using the primary dispersion of the protective layer.
[Adjustment of protective liquid]
Primary dispersion of protective layer 10 parts 10% PVA aqueous solution 20 parts 12.5% epichlorohydrin aqueous solution 5 parts 30% zinc stearate dispersion 2 parts A mixture of the above composition is pulverized to a mean particle size of 1 μm or less with a vertical sand mill The protective layer solution was prepared by dispersing.

On the thermosensitive coloring layer, the protective layer solution is applied and dried so that the weight when dried is about 3 g / m ^2, and further super calendered so that the Oken smoothness becomes 2000 seconds. A thermal recording paper was obtained.
A thermosensitive adhesive layer was provided on the back surface of the thermosensitive coloring layer in the same manner as in Example 18 to obtain a thermosensitive adhesive sheet.

Comparative Example 1
In Example 1, a heat-sensitive adhesive sheet was obtained in the same manner as in Example 1 except that [Liquid A] and [Liquid B-1] were replaced with [Liquid J] and [Liquid K] below. It was.
[Liquid J] Phosphate ester compound dispersion liquid Resorcinol bis [di (2,6-dimethylphenyl) phosphate] 30.0 parts Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) ) 0.15 parts water 64.85 parts

[Liquid K] hindered phenol compound dispersion 1,1,3-tris (2-methyl-4-
Hydroxy-5-t-butylphenyl) butane 30.0 parts Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts

Comparative Example 2
In Comparative Example 1, a heat-sensitive adhesive sheet was obtained in the same manner as in Comparative Example 1 except that the [K liquid] was replaced with the following [L liquid].
[Liquid L] hindered phenol compound dispersion liquid tetrakis [methylene-3- (3 ′, 5′-di-t-butyl
-4-hydroxyphenyl) propionate] methane 30.0 parts polyvinyl alcohol (30% aqueous solution) 5.0 parts surfactant (alkyl-allyl sulfonate) 0.15 parts water 64.85 parts

Comparative Example 3
In Comparative Example 1, a heat-sensitive adhesive sheet was obtained in the same manner as in Comparative Example 1 except that [J liquid] was replaced with the following [M liquid].
[Liquid M] Phthalic acid ester compound dispersion liquid Bis (dimethylcyclohexyl) phthalate 30.0 parts Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64. 85 parts

Comparative Example 4
In Example 2, a heat-sensitive adhesive sheet was obtained in the same manner as in Example 2 except that [A liquid] was replaced with the following [N liquid].
[N solution] Diester compound dispersion dimethyl terephthalate 30.0 parts Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts

Comparative Example 5
In Example 4, a heat-sensitive adhesive sheet was obtained in the same manner as in Example 4 except that [A liquid] was replaced with the following [N liquid].
[N solution] Diester compound dispersion dimethyl terephthalate 30.0 parts Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts

Comparative Example 6
In Comparative Example 1, a heat-sensitive adhesive sheet was obtained in the same manner as in Comparative Example 1 except that [J liquid] was replaced with the following [A liquid].
[Liquid A] Diester compound dispersion 30.0 parts of diester compound represented by the following formula (I)

ポリビニルアルコール（３０％水溶液） ５．０部
界面活性剤（アルキル−アリルスルホン酸塩） ０．１５部
水 ６４．８５部

Polyvinyl alcohol (30% aqueous solution) 5.0 parts Surfactant (alkyl-allyl sulfonate) 0.15 parts Water 64.85 parts

Comparative Example 7
In Comparative Example 1, a heat-sensitive adhesive sheet was obtained in the same manner as in Comparative Example 1, except that [Liquid J] was replaced with [Liquid A] and [Liquid K] was replaced with [Liquid L] below. It was.
[Liquid L] hindered phenol compound dispersion liquid tetrakis [methylene-3- (3 ′, 5′-di-t-butyl
-4-hydroxyphenyl) propionate] methane 30.0 parts polyvinyl alcohol (30% aqueous solution) 5.0 parts surfactant (alkyl-allyl sulfonate) 0.15 parts water 64.85 parts

<Adhesive properties>
Adhesive strength measurement A heat-sensitive adhesive sheet is cut into a 40 mm × 150 mm rectangle to form a heat-sensitive adhesive label, using a thermal printing device TH-PMD manufactured by Okura Electric Co., Ltd. Thermal activation was performed under the conditions of line and platen pressure of 6 kgf / line. Subsequently, the cardboard was affixed in the longitudinal direction with a 2 kg pressure rubber roller and peeled after 2 minutes under the conditions of a peeling angle of 180 degrees and a peeling speed of 300 mm / min. The adhesive strength at that time was measured with a force gauge, and the data obtained by reading and averaging the data at 0.1 second intervals are shown in Table 2. The unit is gf / 40 mm. This test was measured in a low temperature (0 ° C., 35% RH), normal temperature (22 ° C., 65% RH), and high temperature (40 ° C., 65% RH) environment.

<Blocking property>
Blocking rank evaluation The surface of the same sample and the heat-sensitive adhesive layer surface were brought into contact with each other, tested at 200 g / cm ² at 60 ° C. under dry conditions for 24 hours, then left at room temperature, and then the sample was peeled off. The sex was evaluated according to the rank shown in Table 1.

About Examples 1-19 and Comparative Examples 1-7, it shows in Table 2 about the measurement result of the adhesion characteristic and blocking property.
In addition, the adhesive strength rank in Table 2 was shown on the following reference | standard.
A: 1000 gf / 40 mm or more
○: 500 gf / 40 mm or more and less than 1000 gf / 40 mm
Δ: 100 gf / 40 mm or more and less than 500 gf / 40 mm
X: Less than 100 gf / 40 mm

Claims (13)

In a thermosensitive adhesive composed mainly of an adhesive component made of a thermoplastic resin and a solid plasticizer, the solid plasticizer is represented by the following structural formula (I) and at least one compound selected from benzotriazole compounds and phosphine compounds. A heat-sensitive adhesive comprising a combination with the represented diester compound.

The heat-sensitive adhesive according to claim 1, wherein the benzotriazole-based compound is a compound represented by the following structural formula (II).

The heat-sensitive adhesive according to claim 1 or 2, wherein the phosphine compound is a compound represented by the following structural formula (III).

  The heat-sensitive adhesive according to any one of claims 1 to 3, wherein the benzotriazole-based compound is contained in an amount of 50 to 500 parts by weight based on 100 parts by weight of a thermoplastic resin (adhesive component).   The heat-sensitive adhesive according to any one of claims 1 to 4, wherein the phosphine compound is contained in an amount of 50 to 500 parts by weight based on 100 parts by weight of a thermoplastic resin (adhesive component).   The heat-sensitive adhesive according to any one of claims 1 to 5, wherein the diester compound is contained in an amount of 10 to 200 parts by weight based on 100 parts by weight of a thermoplastic resin (adhesive component).   The heat-sensitive adhesive according to any one of claims 1 to 6, further comprising a tackifier in the heat-sensitive adhesive.   A heat-sensitive adhesive material comprising a layer made of the heat-sensitive adhesive according to claim 1 on one side of a substrate.   9. The heat-sensitive adhesive material according to claim 8, wherein an intermediate layer mainly comprising fine hollow particles and a binder is provided between the heat-sensitive adhesive layer and the substrate.   The heat-sensitive adhesive material according to claim 8 or 9, wherein a recording layer is provided on a surface of the substrate opposite to the heat-sensitive adhesive layer.   The heat-sensitive adhesive material according to claim 10, wherein the recording layer is any one of a heat-sensitive recording layer, an inkjet recording layer, a thermal transfer ink receiving layer, and an electrophotographic recording layer. The heat-sensitive adhesive material according to claim 11, wherein the heat-sensitive recording layer is a heat-sensitive recording layer containing at least a leuco dye and a developer.
The heat-sensitive adhesive material according to any one of claims 8 to 12, wherein the heat-sensitive adhesive material is in a label shape, a sheet shape, or a roll shape.