JP4990512B2 - Heat sensitive adhesive material - Google Patents

Description

  The present invention has a heat-sensitive adhesive layer that is non-adhesive at normal temperature but develops adhesiveness upon heating, and also maintains adhesiveness even after the occurrence of adhesiveness. It is related with the heat-sensitive adhesive material which can be heat-activated by.

  Adhesive label sheets are increasingly used for purposes such as price display labels, product display (barcode) labels, quality display labels, weighing display labels, and advertising labels (stickers). Various methods such as an ink jet recording method, a thermal recording method, and a pressure sensitive recording method have been developed as a label recording method.

  As such an adhesive label sheet, for example, a structure in which an adhesive layer and release paper are laminated on the side opposite to the information recording surface of the label is generally used. It is widely used because it can be bonded together. In a general adhesive label sheet, the release paper is used after being peeled off. However, the peeled release paper is difficult to be reused by collection and is almost always discarded. Thus, in recent years, attention has been paid to a heat-sensitive adhesive label sheet as a heat-sensitive adhesive material having a heat-sensitive adhesive layer that does not exhibit adhesiveness at room temperature and does not require a release paper (see Patent Document 1).

The heat-sensitive adhesive layer in such a heat-sensitive adhesive label sheet contains, for example, a thermoplastic resin and a heat-meltable substance, and further contains a tackifier as necessary (see Non-Patent Document 1).
However, after the heat-sensitive adhesive layer in the heat-sensitive adhesive label sheet exhibits adhesiveness, the adhesive strength decreases with time, and high thermal energy is required when thermally activated.
Therefore, in order to improve this point, for example, a heat insulating layer containing plastic hollow particles and a water-soluble binder is provided between the support and the heat-sensitive adhesive layer to reduce thermal energy when thermally activated ( It has been proposed to increase the sensitivity (see Patent Document 2 and Patent Document 3). According to the proposal, a relatively good result can be obtained with respect to reduction of thermal energy when the heat-sensitive adhesive layer is thermally activated. However, in this proposal, since a water-soluble binder that does not exhibit adhesiveness at room temperature is used, the adhesive strength to rough surface adherends such as cardboard and polyolefin wrap has not yet reached a practical level. In addition, the problem that the adhesive strength after the adhesiveness has deteriorated over time has not yet been solved, and further improvement and development are desired.

In addition, from the viewpoints of water resistance, label strength, and smoothness, the demand for films and synthetic paper is rapidly increasing as a support. With respect to the growth in demand for films and synthetic papers as such supports, heat-sensitive adhesives are not able to enter. There are the following reasons why this is not possible.
(1) Since the support is a film or synthetic paper, the heat-sensitive adhesive layer is less likely to permeate, and problems such as repellency, pinholes, and irregularities are likely to occur during production.
(2) Since the support is a film or synthetic paper, the anchoring property with the active layer is low, and the layer tends to fall off during thermal activation.
(3) Since the support is a film or synthetic paper, the support itself tends to shrink into wrinkles during thermal activation.
(4) Since the support is a film or synthetic paper, the strength is high and it is difficult to tear, so when trying to peel off the label affixed to the product, only the heat-sensitive adhesive layer remains on the product (adhesive residue) ) It looks bad.

  The above (1) can be improved by optimizing the addition amount of the surfactant and dispersant added to the heat-sensitive adhesive layer, etc., but the above (2), (3) and (4) This is a problem peculiar to heat-sensitive adhesive materials using film and synthetic paper, and it has not been completely improved at present.

Japanese Utility Model Publication No. 6-25869 Japanese Patent No. 2683733 Japanese Patent Laid-Open No. 10-152660 "Adhesion Handbook" 12th edition, pages (131-135), published in 1970

  An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention has strong adhesion to rough surface adherends such as corrugated cardboard and polyolefin wrap, has little decrease in adhesion over time, can be thermally activated with low energy, and has good blocking resistance. In particular, even when synthetic paper or plastic film is used as the support, the heat-sensitive adhesive layer does not fall off during thermal activation, shrinkage wrinkles of the support can be prevented, and adhesive residue remains when the label is replaced It is an object to provide a heat-sensitive adhesive material free from heat.

  As a result of intensive studies by the present inventors in order to solve the above problems, the following knowledge has been obtained. That is, at least an under layer and a heat-sensitive adhesive layer are provided in this order on one surface of the support, and the under layer has a thermoplastic resin and hollow with a glass transition temperature (Tg) of −70 ° C. or higher and lower than 0 ° C. By containing a filler, the adhesive strength to rough surface adherends such as corrugated cardboard and polyolefin wrap is strong, there is little decrease in adhesive strength over time, thermal activation is possible with low energy, and blocking resistance is also good It was found that it was good.

The present invention is based on the above findings by the present inventors, and means for solving the above problems are as follows. That is,
<1> A support and at least an under layer and a heat-sensitive adhesive layer on the one surface of the support in this order,
The under layer is a thermosensitive adhesive material containing a thermoplastic resin having a glass transition temperature (Tg) of −70 ° C. or higher and lower than 0 ° C. and a hollow filler.
<2> The heat-sensitive adhesive layer according to <1>, wherein the heat-sensitive adhesive layer contains a thermoplastic resin, a tackifier, and a heat-meltable substance.
<3> The thermoplastic resin in the under layer is an acrylic acid ester copolymer, a methacrylic acid ester copolymer, an acrylic acid ester-methacrylic acid ester copolymer, an acrylic acid ester-styrene copolymer, an acrylic acid ester-methacrylic acid. The heat-sensitive adhesive material according to any one of <1> to <2>, which is at least one selected from an acid ester-styrene copolymer and an ethylene-vinyl acetate copolymer.
<4> The hollow filler in the under layer is a spherical hollow particle having a volume average particle diameter of 2.0 to 5.0 μm, and the hollow ratio of the spherical hollow particle is 70% or more. <1> to <3> The heat-sensitive adhesive material according to any one of the above.
<5> The material of the spherical hollow particles is a plastic, and the plastic is at least one selected from an acrylonitrile-vinylidene chloride-methyl methacrylate copolymer and an acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer. The heat-sensitive adhesive material according to <4>.
<6> Any one of <1> to <5>, wherein a mass ratio of the thermoplastic resin and the hollow filler in the under layer is 0.1 to 2 parts by mass of the hollow filler with respect to 1 part by mass of the thermoplastic resin. The heat-sensitive adhesive material described in 1.
<7> Any of <1> to <6>, wherein the mixing mass ratio (hollow filler: thermoplastic resin) of the hollow filler and the thermoplastic resin in the under layer is 1: 0.5 to 1: 3.0 A heat-sensitive adhesive material according to any one of the above.
<8> Any one of <1> to <6>, wherein a mixing mass ratio of the hollow filler and the thermoplastic resin in the under layer (hollow filler: thermoplastic resin) is 1: 6.0 to 1: 20.0. A heat-sensitive adhesive material according to any one of the above.
<9> The thermoplastic resin in the heat-sensitive adhesive layer is an acrylic ester copolymer, a methacrylic ester copolymer, an acrylic ester-methacrylic ester copolymer, an acrylic ester-styrene copolymer, or an acrylic ester. -The heat-sensitive adhesive material according to any one of <2> to <8>, which is at least one selected from a methacrylic acid ester-styrene copolymer and an ethylene-vinyl acetate copolymer.
<10> The heat-sensitive adhesive material according to any one of <2> to <9>, wherein the heat-meltable substance in the heat-sensitive adhesive layer is a benzotriazole compound represented by the following structural formula (1).
However, in the structural formula (1), R ¹ and R ² may be the same as or different from each other, and represent any one of a hydrogen atom, an alkyl group, and an α, α-dimethylbenzyl group. . X represents a hydrogen atom or a halogen atom.
<11> The heat-sensitive adhesive material according to any one of <2> to <10>, wherein the heat-meltable substance in the heat-sensitive adhesive layer is a hydroxybenzoic acid ester compound represented by the following structural formula (2). is there.
However, in the structural formula (2), R ³ represents any of an alkyl group, an alkenyl group, an aralkyl group, and an aryl group, and these may be further substituted with a substituent.
<12> The heat-meltable substance in the heat-sensitive adhesive layer is a compound represented by any one of the following structural formulas (3), (4), and (5), and any one of <2> to <11> The heat-sensitive adhesive material described.
However, in the structural formula (3), R ⁴ and R ⁵ may be the same as or different from each other, and represent an alkyl group or an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.
However, in the structural formula (4), R ⁶ represents any one of a hydrogen atom, a halogen atom, an alkyl group, and an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.
In the Structural Formula (5), R ⁷ represents any one of hydrogen atom, halogen atom, alkyl group and alkoxy group.
<13> The heat sensitive adhesive layer further includes a eutectic agent, and the eutectic agent is a dibenzyl ester oxalate compound represented by the following structural formula (6). The heat-sensitive adhesive material described.
However, in Structural Formula (6), Z represents one of a hydrogen atom, a halogen atom, and an alkyl group.
<14> The heat-sensitive adhesive material according to any one of <1> to <13>, wherein the total thickness of the under layer and the heat-sensitive adhesive layer is 13 to 30 μm.
<15> The heat-sensitive adhesive material according to any one of the items <1> to <14>, which has a recording layer and a protective layer in this order on the surface of the support that does not have the heat-sensitive adhesive layer.
<16> The above <15>, wherein the recording layer is any one of a heat-sensitive recording layer, a thermal melt transfer recording ink receiving layer, an electrophotographic toner image receiving layer, a silver halide photographic recording layer, and an inkjet ink receiving layer. The heat-sensitive adhesive material described in 1.
<17> The heat-sensitive adhesive material according to <16>, wherein the heat-sensitive recording layer contains a leuco dye and a developer.
<18> The heat-sensitive adhesive material according to any one of <15> to <17>, wherein the protective layer contains polyvinyl alcohol having a reactive carbonyl group and a hydrazide compound.
<19> The heat-sensitive adhesive material according to any one of <15> to <18>, having an ink image formed with a UV curable ink.
<20> The thermal recording according to any one of <15> to <19>, wherein the recording layer surface is pre-printed with visual information, and the thermosensitive adhesive layer surface is subjected to eye mark printing having a sensing function. Adhesive material.
<21> The heat-sensitive adhesive material according to any one of <1> to <20>, wherein the support is any one of synthetic paper and a plastic film.
<22> The heat-sensitive adhesive material according to any one of <1> to <21>, which is any one of a label shape, a sheet shape, a label sheet shape, and a roll shape.

  In the heat-sensitive adhesive material of the present invention, an under layer containing a thermoplastic resin having a glass transition temperature (Tg) of −70 ° C. or more and less than 0 ° C. and a hollow filler is provided between the heat-sensitive adhesive layer and the support. By providing, the heat-sensitive adhesive layer and the under layer are mixed at the time of heating, and by increasing the amount of the adhesive, the adhesive force to rough surface adherends such as cardboard and polyolefin wrap is strengthened. In addition, by using plastic spherical hollow particles having a high hollow ratio for the under layer, a heat insulating effect is produced, and the heat-sensitive adhesive layer provided on the upper layer can be thermally activated with low energy, and the blocking resistance is improved. It becomes possible. Furthermore, even when synthetic paper or plastic film is used as the support, the heat-sensitive adhesive layer does not fall off during thermal activation, and shrinkage wrinkles of the support can be prevented. can do.

  According to the present invention, it is possible to solve various problems in the past, strong adhesion to rough surface adherends such as corrugated cardboard and polyolefin wrap, less decrease in adhesion over time, and heat activation with low energy, In addition, the anti-blocking property is also good. In particular, even when a synthetic paper or plastic film is used as the support, the heat-sensitive adhesive layer does not fall off during thermal activation, and the generation of shrinkage wrinkles on the support can be prevented. It is possible to provide a heat-sensitive adhesive material that does not cause adhesive residue during re-covering.

(Heat-sensitive adhesive material)
The heat-sensitive adhesive material of the present invention has a support and at least an under layer and a heat-sensitive adhesive layer in this order on one surface of the support, and further includes other layers as necessary. Become. Various recording layers and protective layers are provided on the other surface of the support that does not have the under layer and the heat-sensitive adhesive layer.

<Support>
The support is not particularly limited in its shape, structure, size and the like, and can be appropriately selected according to the purpose. Examples of the shape include a flat plate shape, May be a single layer structure or a laminated structure, and the size may be appropriately selected according to the size of the heat-sensitive adhesive material.

There is no restriction | limiting in particular as a material of the said support body, According to the objective, it can select suitably, For example, an inorganic material or an organic material is mentioned. Examples of the inorganic material include glass, quartz, silicon, silicon oxide, aluminum oxide, SiO ₂ and metal. Examples of the organic material include paper such as fine paper, art paper, coated paper, and synthetic paper, cellulose derivatives such as cellulose triacetate, polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate, polycarbonate, polystyrene, poly Examples thereof include polyolefins such as methyl methacrylate, polyamide, polyethylene, and polypropylene. Among these, fine paper, coated paper, plastic film, and synthetic paper are preferable, and plastic film and synthetic paper are particularly preferable.
Examples of the synthetic paper include those made of synthetic fibers such as polyethylene, polypropylene, polyethylene terephthalate, and polyamide, and those that are affixed to a part, one side, or both sides of the paper. As the synthetic paper, commercially available products include FPG, FGS, GFG, KPK and the like manufactured by Oji Oil Chemical Co., Ltd.
In the case where the support is a film or synthetic paper, the heat-sensitive adhesive layer or the like is not soaked and the anchoring property is extremely low as compared with high-quality paper made of pulp or used paper. Furthermore, a contact activation method using a thermal head has attracted attention as a recent thermal activation method because of safety, high speed, and on-demand trend. Contact thermal activity by the thermal head has the side effect of scraping off the surface of the active layer, especially in thermal activation, the thermal head itself becomes high temperature to activate the entire surface of the label, and the heat-sensitive adhesive layer falls off significantly, In the present invention, even when a film or synthetic paper is used as the support, it is possible to prevent the film and synthetic paper from falling off and shrinking during thermal activation, and no adhesive residue is left when relabeling. is there.

The support is preferably surface-modified by corona discharge treatment, oxidation reaction treatment (chromic acid, etc.), etching treatment, easy adhesion treatment, antistatic treatment, etc. for the purpose of improving the adhesion of the coating layer. Moreover, it is preferable to add a white pigment such as titanium oxide to the support to make it white.
There is no restriction | limiting in particular as thickness of the said support body, According to the objective, it can select suitably, 50-2,000 micrometers is preferable and 100-1,000 micrometers is more preferable.

<Under layer>
The under layer contains a thermoplastic resin having a glass transition temperature (Tg) of −70 ° C. or more and less than 0 ° C. and a hollow filler, and further contains other components as necessary. The glass transition temperature is preferably -70 to -2 ° C, more preferably -70 to -5 ° C.

-Thermoplastic resin-
The thermoplastic resin having a glass transition temperature (Tg) of −70 ° C. or higher and lower than 0 ° C. is not particularly limited and may be appropriately selected depending on the intended purpose. For example, natural rubber obtained by graft copolymerization with a vinyl monomer. Latex, acrylic acid ester copolymer, methacrylic acid ester copolymer, acrylic acid ester-methacrylic acid ester copolymer, acrylic acid ester-styrene copolymer, acrylic acid ester-methacrylic acid ester-styrene copolymer, ethylene -Vinyl acetate copolymer etc. are mentioned, These may be used individually by 1 type and may use 2 or more types together.
When a thermoplastic resin having a high glass transition temperature (Tg) exceeding the glass transition temperature (Tg) range of the thermoplastic resin in the under layer is used, the characteristics of the under layer cannot be obtained at all, and rough surface adherends such as cardboard In addition, the adhesive strength to the polyolefin wrap is weakened, and only the heat-sensitive adhesive layer provided on the upper layer becomes the adhesive strength.

-Hollow filler-
There is no restriction | limiting in particular as said hollow filler, The inorganic filler or organic filler with a volume average particle diameter of 0.5-10 micrometers generally used is used. Examples of the inorganic filler include calcium carbonate, silica, titanium oxide, aluminum hydroxide, clay, calcined clay, magnesium silicate, magnesium carbonate, white carbon, zinc oxide, barium sulfate, surface-treated calcium carbonate, silica and the like. Is mentioned.
Examples of the organic filler include fine powders such as urea-formalin resin, styrene-methacrylic acid copolymer, polystyrene resin, and the like.
Among these, in consideration of the problem of low energy thermal activation (high sensitivity thermal activation), a plastic having a volume average particle diameter of 2.0 to 5.0 μm having a heat insulating effect and a hollow ratio of 70% or more. Spherical hollow particles are preferred. More preferably, the hollow particles have a maximum particle diameter of 10.0 μm or less, a volume average particle diameter of 2.0 to 5.0 μm, and a hollow ratio of 70% or more.
Those having a low hollow ratio have an insufficient heat insulation effect, so that heat energy from the thermal head is released to the outside through the support, resulting in poor high sensitivity thermal activation effect. When the volume average particle diameter is larger than 5.0 μm, when a heat-sensitive adhesive layer is provided on the under layer using these, a portion where the heat-sensitive adhesive layer is not formed is formed on the large particle portion, and heat activation is performed. In such a case, the adhesive strength tends to decrease, and if it is less than 2.0 μm, it becomes difficult to ensure a hollow ratio of 70% or more, and as a result, the high-sensitivity thermal activation effect may be inferior. .

The plastic spherical hollow particle means a hollow particle which is already foamed with a thermoplastic resin as a shell and containing air or other gas inside.
Here, the said hollow ratio means the ratio of the outer diameter of a hollow microparticle, and an internal diameter, and is represented by following Numerical formula 1.
<Formula 1>
Hollow ratio (%) = (inner diameter of hollow fine particles) / (outer diameter of hollow fine particles) × 100

  Further, the hollow ratio of the hollow particles used for the under layer is preferably 70% or more from the viewpoint of securing the adhesive force in the thermal activation method using a thermal head.

  As a material constituting the plastic spherical hollow particles satisfying the above conditions, for example, either acrylonitrile-vinylidene chloride-methyl methacrylate copolymer or acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer is preferable.

  The mass ratio of the thermoplastic resin having a glass transition temperature (Tg) in the under layer of −70 ° C. or higher and lower than 0 ° C. to the hollow filler is 0.1 to 0.1 parts by mass of the hollow filler relative to 1 part by mass of the thermoplastic resin. 2 parts by mass is preferred. When the hollow filler is less than 0.1 parts by mass, it is inferior to high-sensitivity thermal activation, and the blocking property may be lowered. When it exceeds 2 parts by mass, it is suitable for rough surface adherends such as cardboard and polyolefin wrap. In some cases, the adhesive strength is reduced, and only the heat-sensitive adhesive layer provided in the upper layer becomes an adhesive strength.

The mixing mass ratio of the hollow filler and the thermoplastic resin in the under layer (hollow filler: thermoplastic resin) is preferably 1: 0.5 to 1: 3.0, and 1: 1.5 to 1: 2.5. Is more preferable. In this range, a heat-sensitive adhesive material having excellent adhesion to a mirror surface such as SUS can be obtained.
Moreover, the mixing mass ratio (hollow filler: thermoplastic resin) of the hollow filler and the thermoplastic resin in the under layer is preferably 1: 6.0 to 1: 20.0, and 1: 8.0 to 1:16. 0 is more preferable. In this range, a heat-sensitive adhesive material having excellent adhesion to a mirror surface and a cardboard surface can be obtained.

The under layer is not particularly limited and can be formed according to a known method. For example, the under layer can be suitably formed by a coating method using an under layer coating solution obtained by blending the above components.
As the coating method, for example, 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, AKKU coating method, Examples thereof include a smoothing coating method, a micro gravure coating method, a reverse roll coating method, a four or five roll coating method, a dip coating method, a falling curtain coating method, a slide coating method, and a die coating method.

The coating amount of the under layer coating solution is preferably 1 to 35 g / m ² , more preferably ² to 25 g / m ^{2 in} terms of dry coating amount. When the coating amount of the under layer coating liquid is less than 1 g / m ² , a sufficient adhesive strength effect may not be obtained when performing adhesion by heating, and the heat insulation effect may be inferior, exceeding 35 g / m ² . In this case, the adhesive strength and the heat insulating effect are saturated, which may be economically undesirable.

<Thermosensitive adhesive layer>
The heat-sensitive adhesive layer contains a thermoplastic resin, a tackifier, and a heat-meltable substance, and contains a eutectic agent and, if necessary, other components.

-Thermoplastic resin-
The thermoplastic resin is not particularly limited and may be appropriately selected depending on the purpose. Since it improves, the adhesive force with respect to rough surface adherends, such as cardboard, and polyolefin wrap improves, and is preferred.
Examples of the thermoplastic resin include natural rubber latex obtained by graft copolymerization with a vinyl monomer, acrylic ester copolymer, methacrylic ester copolymer, acrylic ester-methacrylic ester copolymer, acrylic ester- Examples thereof include styrene copolymers, acrylic ester-methacrylic ester-styrene copolymers, and ethylene-vinyl acetate copolymers. These may be used individually by 1 type and may use 2 or more types together.

  10-60 mass% is preferable and, as for content in the said thermosensitive adhesive layer of the said thermoplastic resin, 15-50 mass% is more preferable. When the content of the thermoplastic resin is less than 10% by mass or more than 60% by mass, both are undesirable because the adhesive strength is lowered. Moreover, when the content rate of low Tg resin exceeds 60 mass%, the malfunction on storage (blocking) will arise, such as adhesive force expressing by the temperature in normal storage environment.

-Hot-melting substance-
The heat-meltable substance is solid at normal temperature, so it does not give plasticity to the resin, but it melts by heating and swells or softens the resin, develops adhesiveness, melts by heating, and then slowly crystallizes. Therefore, the adhesiveness can be maintained for a long time even after the heat source is removed.

  As the hot-melt material, for example, a benzotriazole compound represented by the following structural formula (1) is preferable.

However, in the structural formula (1), R ¹ and R ² may be the same as or different from each other, and represent any one of a hydrogen atom, an alkyl group, and an α, α-dimethylbenzyl group. . X represents a hydrogen atom or a halogen atom.

As said alkyl group, a C1-C8 thing is preferable, for example, a methyl group, an ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group etc. These may be further substituted with a substituent.
The substituent may have a hydroxyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, or a specific substituent (for example, may be substituted with a halogen atom or a nitro group). An alkyl group, an aryl group, a heterocyclic group, etc. are mentioned.
Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like.

  Examples of the benzotriazole compound represented by the structural formula (1) include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole and 2- (2′-hydroxy-5′-t-octylphenyl). ) Benzotriazole, 2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-) Amylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-t-butylphenyl) -5-chlorobenzotriazole, 2- [2′-hydroxy-3 ′, 5′-di (1, 1-dimethylbenzyl) phenyl] benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole, 2- (2′-hydroxy) -3'-sec-butyl-5'-t-butylphenyl) benzotriazole. These may be used individually by 1 type and may use 2 or more types together.

  Moreover, as said heat-meltable substance, the hydroxybenzoic acid ester compound represented by following Structural formula (2) is preferable.

However, in the structural formula (2), R ³ represents any one of an alkyl group, an alkenyl group, an aralkyl group, and an aryl group, which may be further substituted with a substituent.

  Examples of the alkyl group include those having 1 to 18 carbon atoms, such as methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, linear alkyl groups such as n-octyl group, n-nonyl group, n-decyl group; isobutyl group, isoamyl group, 2-methylbutyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group 2-ethylbutyl group, 2-methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 2-ethylpentyl group, 3-ethylpentyl group, 2-methylheptyl group, 3- Methylheptyl group, 4-methylheptyl group, 5-methylheptyl group, 2-ethylhexyl group, 3-ethylhexyl group, isopropyl group, sec-butyl group, 1-ethyl Propyl group, 1-methylbutyl group, 1,2-dimethylpropyl group, 1-methylheptyl group, 1-ethylbutyl group, 1,3-dimethylbutyl group, 1,2-dimethylbutyl group, 1-ethyl-2-methyl Propyl group, 1-methylhexyl group, 1-ethylheptyl group, 1-propylbutyl group, 1-isopropyl-2-methylpropyl group, 1-ethyl-2-methylbutyl group, 1-propyl-2-methylpropyl group, 1-ethylhexyl group, 1-propylpentyl group, 1-isopropylpentyl group, 1-isopropyl-2-methylbutyl group, 1-isopropyl-3-methylbutyl group, 1-methyloctyl group, 1-propylhexyl group, 1-isobutyl -3-methylbutyl group, neopentyl group, tert-butyl group, tert-hexyl group, tert-a A branched alkyl group such as an alkyl group, a tert-octyl group; a cyclohexyl group, a 4-methylcyclohexyl group, a 4-ethylcyclohexyl group, a 4-tert-butylcyclohexyl group, a 4- (2-ethylhexyl) cyclohexyl group, a bornyl group, Examples thereof include cycloalkyl groups such as isobornyl group and adamantyl group, and these may be further substituted with a substituent.

  As the alkenyl group, those having 2 to 8 carbon atoms are preferable. For example, vinyl group, allyl group, 1-propenyl group, methacryl group, crotyl group, 1-butenyl group, 3-butenyl group, 2-pentenyl group. Group, 4-pentenyl group, 2-hexenyl group, 5-hexenyl group, 2-heptenyl group, 2-octenyl group and the like, and these may be further substituted with a substituent.

  The aralkyl group is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a benzyl group, a phenylethyl group, a phenylpropyl group, and the like, which are further substituted with a substituent. Also good.

  Examples of the aryl group include a phenyl group, a naphthyl group, an anthranyl group, a fluorenyl group, a phenalenyl group, a phenanthranyl group, a triphenylenyl group, and a pyrenyl group, which may be further substituted with a substituent.

  Examples of the substituent for the alkyl group, alkenyl group, aralkyl group, or aryl group include a hydroxyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, and a specific substituent (for example, a halogen atom). An alkyl group, an aryl group, a heterocyclic group, and the like, which may be substituted by an atom or a nitro group.

  Examples of the hydroxybenzoic acid ester compound represented by the structural formula (2) include, for example, methyl m-hydroxybenzoate, ethyl m-hydroxybenzoate, phenyl m-hydroxybenzoate, methyl p-hydroxybenzoate, p- Ethyl hydroxybenzoate, n-propyl p-hydroxybenzoate, n-butyl p-hydroxybenzoate, stearyl p-hydroxybenzoate, cyclohexyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, p-hydroxybenzoic acid 4 -Chlorobenzyl, 4-methylbenzyl p-hydroxybenzoate, phenyl p-hydroxybenzoate and the like. These may be used individually by 1 type and may use 2 or more types together.

  Moreover, as said heat-meltable substance, the compound represented by either of following Structural formula (3), (4) and (5) is preferable, for example.

However, in the structural formula (3), R ⁴ and R ⁵ may be the same as or different from each other, and represent an alkyl group or an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.

However, in the structural formula (4), R ⁶ represents any one of a hydrogen atom, a halogen atom, an alkyl group, and an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.

In the Structural Formula (5), R ⁷ represents any one of hydrogen atom, halogen atom, alkyl group and alkoxy group.

In the structural formulas (3) to (5), examples of the alkyl group include those similar to the structural formula (1).
Examples of the alkoxy group include methoxy group, ethoxy group, propyloxy group, i-propyloxy group, butoxy group, i-butoxy group, t-butoxy group, pentyloxy group, hexyloxy group, cyclohexyloxy group, heptyl. Examples thereof include an oxy group, an octyloxy group, a 2-ethylhexyloxy group, a nonyloxy group, a decyloxy group, a 3,7-dimethyloctyloxy group, and a lauryloxy group.

  Examples of the compound represented by the structural formula (3) include Toluoin, Anisoin, m-Anisoin, Deoxytoluin, DeoxyAnisoin, 4,4'-DiethylBenzoin, 4,4'-Diethylbenzoin, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the compound represented by the structural formula (4) include phenyl 1-hydroxy-2-naphthoate, 1-hydroxy-2-naphthoic acid-p-chlorophenyl, 1-hydroxy-2-naphthoic acid-o-. Chlorophenyl, 1-hydroxy-2-naphthoic acid-p-methylphenyl, 1-hydroxy-2-naphthoic acid-o-methylphenyl, 1,4-dihydroxy-2-naphthoic acid phenyl, 1,4-dihydroxy-2- Examples include naphthoic acid-p-chlorophenyl and 1,4-dihydroxy-2-naphthoic acid-o-chlorophenyl. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the compound represented by the structural formula (5) include benzoic acid-3-hydroxyphenyl, benzoic acid-4-hydroxyphenyl, benzoic acid-2-hydroxyphenyl, and o-methylbenzoic acid-3-hydroxyphenyl. , P-chlorobenzoic acid-3-hydroxyphenyl and the like. These may be used individually by 1 type and may use 2 or more types together.

As the compounds represented by the structural formulas (1) to (5), those which are solid at room temperature and melt upon heating are preferably used. The melting point of these compounds is preferably 70 ° C. or higher, more preferably 80 ° C. or higher, and the upper limit is about 200 ° C.
When the melting point is less than 70 ° C., when it is used as a heat-sensitive adhesive, a storage defect (blocking) may occur, for example, an adhesive force may develop at a normal storage environment temperature. In addition, there may be a problem in production such that a heat-sensitive adhesive coating solution is applied on a support and dried to develop an adhesive force. On the other hand, if the melting point exceeds 200 ° C., a large amount of energy is required to develop the adhesive force, which may cause practical problems. In addition, when a thermal recording paper is used as a support and an adhesive force is developed with a large amount of energy, there is a problem that a printed image cannot be read because the thermal recording layer is colored.

  Further, by making the volume average particle diameter of the heat-meltable substance represented by the structural formulas (1) to (5) 0.5 μm or less, the dynamic thermal sensitivity is increased and the thermoplastic resin and tackifying are performed with low energy. It becomes a heat-activatable adhesive by being compatible with the agent. Furthermore, by setting it as the said volume average particle diameter, the preservability in the normal storage environment temperature improves (blocking resistance improves).

  The total content of the compounds represented by the structural formulas (1) to (5) as the hot-melt material is preferably 25 to 80% by mass, and more preferably 35 to 70% by mass. When the content of the heat-meltable substance is less than 25% by mass, when combined with a thermoplastic resin having a glass transition temperature (Tg), a storage defect such as an adhesive force is exhibited at a normal storage environment temperature. (Blocking) may occur or the adhesive strength may be reduced, and if it exceeds 80% by mass, the adhesive strength may be reduced.

-Tackifier-
The tackifier is added to improve the adhesive strength of the heat-sensitive adhesive layer, and is not particularly limited and can be appropriately selected from known ones according to the purpose. For example, a rosin derivative (for example, rosin , Polymerized rosin, hydrogenated rosin), terpene resins (for example, terpene resins, aromatic modified terpene resins, terpene phenol resins, hydrogenated terpene resins), petroleum resins, phenol resins, xylene resins and the like. These tackifiers are compatible with the thermoplastic resin and the hot-melt material, and can significantly improve the adhesive force of the heat-sensitive adhesive layer.

  The melting point (or softening point) of the tackifier is preferably 80 ° C. or higher, and more preferably 80 to 200 ° C. If the melting point (or softening point) is less than 80 ° C., storage defects (decrease in blocking resistance) may occur at normal storage environment temperatures.

  The content of the tackifier in the heat-sensitive adhesive layer is preferably 1 to 30% by mass, and more preferably 1 to 20% by mass. When the content is less than 1% by mass, the adhesive strength may be remarkably lowered. When the content exceeds 30% by mass, storage defects (decrease in blocking resistance) or low temperature environment occur under normal storage environment temperatures. Lowering of initial adhesive strength may occur.

-Eutectic agent-
As the eutectic agent, a compound that is solid at room temperature and melts when heated is suitably used. The melting point of the compound is preferably 70 ° C. or higher, more preferably 80 ° C. or higher, and the upper limit is about 150 ° C. When the melting point is less than 70 ° C., when it is used as a heat-sensitive adhesive, an adhesive force develops at a temperature in a normal storage environment, such as a storage failure (blocking) occurs, or a heat-sensitive adhesive is applied. When the liquid is applied to the support and dried, there may be a manufacturing problem that the adhesive force develops. On the other hand, if the melting point exceeds 150 ° C., the effect of eutecticizing the hot-melt material may be lost.

  The eutectic agent is not particularly limited and can be appropriately selected from known ones according to the purpose. However, the eutectic agent is excellent in the effect of eutecticizing the hot-melt material and the compatibility with the thermoplastic resin. In view of this, oxalic acid dibenzyl ester compounds represented by the following structural formula (6) are preferred.

However, in Structural Formula (6), Z represents one of a hydrogen atom, a halogen atom, and an alkyl group.
In addition, examples of the alkyl group and the halogen atom include those similar to the structural formula (1).

  Examples of the oxalic acid dibenzyl ester compound represented by the structural formula (6) include oxalic acid di-p-methylbenzyl ester, oxalic acid di-p-ethylbenzyl ester, oxalic acid di-p-chlorobenzyl ester, and oxalic acid dibenzyl. Examples include esters. These may be used individually by 1 type and may use 2 or more types together.

  In addition to the above-mentioned components, the heat-sensitive adhesive layer has an inorganic substance such as titanium oxide, alumina, colloidal silica, kaolin, talc, stearic acid metal salt, paraffin, natural wax, synthetic wax, natural fat and oil to prevent blocking. Organic substances such as polystyrene powder can be added, and other components such as a dispersant, an antifoaming agent, and a thickener can be added as necessary.

The heat-sensitive adhesive layer is not particularly limited and can be formed according to a known method. For example, the heat-sensitive adhesive layer can be suitably formed by a coating method using a heat-sensitive adhesive layer coating liquid containing the above components. it can.
As the coating method, for example, 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, AKKU coating method, Examples thereof include a smoothing coating method, a micro gravure coating method, a reverse roll coating method, a four or five roll coating method, a dip coating method, a falling curtain coating method, a slide coating method, and a die coating method.
It should be noted that the drying conditions during the coating or printing must be dried in a temperature range in which the hot-melt material and the eutectic agent used do 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 coating liquid is preferably usually 5 to 30 g / ^{m 2} on a dry coating amount, 5 to 20 g / ^{m 2} is more preferable. When the coating amount of the heat-sensitive adhesive layer coating solution is less than 5 g / m ² , sufficient adhesion may not be obtained when performing adhesion by heating, and the under layer has a glass transition temperature (Tg). Since a low-temperature thermoplastic resin is used, blocking resistance may be inferior, and if it exceeds 30 g / m ² , the heat insulating effect of the under layer is reduced, and the economical efficiency is deteriorated.
The total thickness of the under layer and the heat-sensitive adhesive layer is preferably 13 to 30 μm. Moreover, it is preferable that the thickness of the thermosensitive adhesive layer with respect to the thickness of an under layer is 30% or more and 70% or less.
When the total thickness is less than 13 μm, it becomes difficult to stick to a non-mirror surface adherend such as corrugated cardboard, and when it exceeds 30 μm, delamination between the under layer and the heat-sensitive adhesive layer occurs, May occur. Furthermore, the active energy can be further reduced by setting the thickness of the heat-sensitive adhesive layer to 30% or more and 70% or less. In general, as the thickness of the heat-sensitive adhesive layer increases, more active energy is required. Therefore, when the thickness of the heat-sensitive adhesive layer exceeds 70%, the film, which is a support, is synthesized with more active energy than necessary. Paper tends to shrink by heat. On the other hand, when the thickness of the heat-sensitive adhesive layer is less than 30%, the anchor effect on the uneven adherend is lost, and the sticking effect may be significantly reduced.

  The heat-sensitive adhesive material of the present invention has the above-described structure, and thus has a strong adhesive force to each adherend, particularly a rough adherend such as corrugated cardboard or polyolefin wrap, low energy thermal activation, and blocking resistance. Is also good.

  Next, the heat-sensitive adhesive material of the present invention preferably has a recording layer and a protective layer in this order on the surface of the support that does not have the heat-sensitive adhesive layer, and further if necessary. It has the layer of.

  The recording layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the recording layer may be a heat-sensitive recording layer, an ink-receiving layer for hot-melt transfer recording, a toner image-receiving layer for electrophotography, or a halogenated film. It is preferably either a silver photographic recording layer or an ink jet ink image receiving layer. Among these, as the recording layer, a heat-sensitive adhesive material for heat-sensitive recording provided with a heat-sensitive recording layer containing a leuco dye and a developer, or an ink-receiving layer for hot-melt transfer recording was provided as the recording layer. The heat-sensitive adhesive material for thermal transfer recording has strong adhesion to various adherends, especially rough surface adherends such as cardboard and polyolefin wrap, low energy thermal activation, and good blocking resistance. Useful.

<Thermosensitive adhesive material for thermal recording>
The heat-sensitive recording layer in the heat-sensitive adhesive material for heat-sensitive recording contains a color former, a developer, and a binder resin, and further contains other components as necessary.

The leuco dye is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, triphenylmethane dyes, fluoran dyes, phenothiazine dyes, auramine dyes, spiropyran dyes Indolinophthalide dyes are publicly listed.
Examples of the leuco dye include 3,3-bis (p-dimethylaminophenyl) phthalide, 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- N-p-tolyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 2- {N- (3'-trifluoromethyl) Phenyl) amino} -6-diethylaminofluorane, 2- {3,6-bis (diethylamino) -9- (o-chloroanilino) xanthylbenzoate lactam}, 3-diethylamino-6-methyl-7- (m-trichloro) Methylanilino) fluorane, 3-diethylamino-7- (o-chloroanilino) fluorane, 3-dibutylamino-7- (o-chloroanilino) fluorane, 3-N-methyl-N-amylamino-6-methyl-7-ani Linofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluorane, 3-diethylamino 6-methyl-7-anilinofluorane, 3- (N, N-diethylamino) -5-methyl-7- (N, N-dibenzylamino) 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'-diethylamino) Phenyl) -3- (2′-methoxy-5′-methylphenyl) phthalide, 3-diethylamino-6-methyl-7- (2 ′, 4′-dimethylanilino) fluoro 3- (2′-methoxy-4′-dimethylaminophenyl) -3- (2′-hydroxy-4′-chloro-5′-methylphenyl) phthalide, 3-morpholino-7- (N-propyl- Trifluoromethylanilino) fluorane, 3-pyrrolidino-7-trifluoromethylanilinofluorane, 3-diethylamino-5-chloro-7- (N-benzyl-trifluoromethylanilino) fluorane, 3-pyrrolidino-7 -(Di-p-chlorophenyl) methylaminofluorane, 3-diethylamino-5-chloro-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′0-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- (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-tetra Chlorophthalide, 3-bis {1,1-bis (4-pyrrolidinophenyl) ethylene-2-yl} -5,6-dichloro-4,7-dibromophthalide, bis (p-dimethylaminostyryl)- 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-ethoxy) (Lopyl) 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-N-isoamyl-6-methyl-7-anilino Examples include fluoran. These may be used individually by 1 type and may use 2 or more types together.

  The developer is not particularly limited and can be appropriately selected from known electron-accepting compounds according to the purpose. For example, phenolic compounds, thiophenolic compounds, thiourea derivatives, organic acids Or the metal salt etc. are mentioned. Examples of the developer include 4,4'-isopropylidenebisphenol, 3,4'-isopropylidenebisphenol, 4,4'-isopropylidenebis (o-methylphenol), 4,4'-secondary butylidene. Bisphenol, 4,4'-isopropylidenebis (o-tertiarybutylphenol), 4,4'-cyclohexylidene diphenol, 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 buty Phenyl) 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, , 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, thiocyanate Zinc acid antipyrine complex, 2-acetyloxy-3-naphthoic acid zinc salt, 2-hydroxy-1-naphthoic acid, 1-hydroxy-2-naphthoic acid, hydroxynaphthoic acid zinc, aluminum, calcium and other metal salts 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 zinc, tetrabromobisphenol A Tetrabromobisphenol S, 4,4′-thiobis (2-methylphenol), 3,4-hydroxy-4′-methyl-diphenylsulfone, 4,4′-thiobis (2-chlorophenol), and the like. These may be used individually by 1 type and may use 2 or more types together.

  The addition amount of the developer in the heat-sensitive recording layer is not particularly limited and may be appropriately selected depending on the purpose. It is preferably 1 to 20 parts by weight with respect to 1 part by weight of the color former, and 2 to 10 parts by weight. Part is more preferred.

  The binder resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, polyvinyl alcohol, starch or derivatives thereof, methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose, ethylcellulose and the like Cellulose derivatives, polyacrylic acid soda, polyvinylpyrrolidone, acrylamide-acrylic acid ester copolymer, acrylamide-acrylic acid ester-methacrylic acid terpolymer, styrene-maleic anhydride copolymer alkali salt, isobutylene-maleic anhydride In addition to water-soluble polymers such as acid copolymer alkali salts, polyacrylamide, sodium alginate, gelatin, and casein, polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic acid ester , Emulsions such as polymethacrylic acid ester, polybutyl methacrylate, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, and latexes such as styrene-butadiene copolymer, styrene-butadiene-acrylic copolymer Etc. These may be used individually by 1 type and may use 2 or more types together.

  Various heat-fusible substances can be used as fillers in the heat-sensitive recording layer. Examples of the heat-fusible substance include 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, behen Fatty acid metal salts such as zinc acid, p-benzylbiphenyl, terphenyl, triphenylmethane, benzyl p-benzyloxybenzoate, β-benzyloxynaphthalene, β-naphthoic acid phenyl ester, 1-hydroxy-2-naphthoic acid phenyl Esters, 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-dibenzyloxynaphth Talene, 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-vinyl Oxyethoxy) biphenyl, p-aryloxybiphenyl, p-propargyloxybiphenyl, dibenzoyloxymethane, 1,3-dibenzoyloxypropane, Benzyl disulfide, 1,1-diphenylethanol, 1,1-diphenylpropanol, p- (benzyloxy) benzyl alcohol, 1,3-diphenoxy-2-propanol, N-octadecylcarbamoyl-p-methoxycarbonylbenzene, N-octadecyl Examples thereof include carbamoylbenzene, succinic acid dibenzyl ester, 1,5-bis (p-methoxyphenyloxy) -3-oxapentane and the like. These may be used individually by 1 type and may use 2 or more types together.

  In the thermosensitive recording layer, various auxiliary additive components such as a surfactant and a lubricant can be used in combination as required. Examples of the lubricant include higher fatty acids or metal salts thereof, higher fatty acid amides, higher fatty acid esters, animal waxes, vegetable waxes, mineral waxes, petroleum waxes and the like.

The heat-sensitive recording layer is not particularly limited and can be formed by a generally known method. For example, a leuco dye, a developer separately from a binder, other components, a ball mill, an attritor, a sand mill, etc. After being pulverized and dispersed with a disperser of 1 to 3 μm until the dispersed particle diameter becomes 1 to 3 μm, the mixture is mixed with a filler, a heat-fusible substance (sensitizer) dispersion liquid, etc., if necessary, and mixed in a predetermined formulation to produce a heat-sensitive recording layer. A thermosensitive recording layer can be formed by preparing a coating solution and coating it on a support.
The thickness of the heat-sensitive recording layer varies depending on the composition of the heat-sensitive recording layer, the application of the heat-sensitive adhesive material, and the like, and cannot be specified unconditionally, but is preferably 1 to 50 μm, more preferably 3 to 20 μm.

<Thermosensitive adhesive material for thermal transfer recording>
The ink-receiving layer for thermal transfer recording in the heat-sensitive adhesive material for thermal transfer recording contains a filler, a binder resin, and a water-proofing agent, and further contains other components as necessary.

  The filler is not particularly limited and can be appropriately selected depending on the purpose. For example, calcium carbonate, silica, titanium oxide, aluminum hydroxide, clay, calcined clay, magnesium silicate, magnesium carbonate, white carbon, Examples thereof include zinc oxide, barium sulfate, surface-treated calcium carbonate and silica, urea-formalin resin, styrene-methacrylic acid copolymer, and fine powders such as polystyrene.

There is no restriction | limiting in particular as said binder resin, According to the objective, it can select suitably from well-known water-soluble resin, For example, polyvinyl alcohol, starch or its derivative, methoxycellulose, hydroxyethylcellulose, carboxymethylcellulose, methylcellulose Cellulose derivatives such as ethyl cellulose; polyacrylic acid soda, polyvinylpyrrolidone, acrylamide-acrylic acid ester copolymer, acrylamide-acrylic acid ester-methacrylic acid terpolymer, styrene-maleic anhydride copolymer alkali salt, isobutylene -Water-soluble polymer compounds such as anhydrous maleic copolymer alkali salt, polyacrylamide, sodium alginate, gelatin, casein and the like. These may be used individually by 1 type and may use 2 or more types together.
The ratio between the filler and the water-soluble resin in the ink-receiving layer is related to blocking properties, and the content ratio (solid content) of the filler to the water-soluble resin is preferably 1: 0.1 to 0.2.

The water-proofing agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include formaldehyde, glyoxal, chrome alum, melamine, melamine-formaldehyde resin, polyamide resin, and polyamide-epichlorohydrin resin. .
The ratio of the water-resistant agent and the water-soluble resin is also related to the blocking property, and the content ratio (solid content) of the water-resistant resin 1 is preferably 0.3 to 0.5. As described above, the ink receiving layer is formed by containing a filler and a water-soluble resin, and further containing a water-soluble resin and a water-proofing agent in a specific ratio. Further, the surface of the ink receiving layer is smoothed by a calendar or the like. By processing at a temperature of 500 seconds or more, the print quality can be further improved in addition to the effect of the filler.

-Protective layer-
The protective layer contains polyvinyl alcohol having a reactive carbonyl group and a hydrazide compound, and further contains other components as necessary.
As described above, the protective layer containing the reactive carbonyl group-containing polyvinyl alcohol and the hydrazide compound as a crosslinking agent is extremely heat-resistant and water-resistant and is hardly affected by the addition of pressure, temperature and humidity. Can be improved.

  The polyvinyl alcohol having a reactive carbonyl group can be produced by a known method such as saponification of a polymer obtained by copolymerizing a vinyl monomer having a reactive carbonyl group and a fatty acid vinyl ester. Examples of the vinyl monomer having a reactive carbonyl group include a group having an ester residue and a group having an acetone group, and a vinyl monomer having a diacetone group is preferable, and specifically, diacetone acrylamide and meta diacetone acrylamide are used. preferable. Examples of the fatty acid vinyl ester include vinyl formate, vinyl acetate, and vinyl propionate. Among these, vinyl acetate is particularly preferable.

The polyvinyl alcohol (PVA) having a reactive carbonyl group may be obtained by copolymerizing another copolymerizable vinyl monomer. Examples of these copolymerizable vinyl monomers include acrylic acid ester, butadiene, ethylene, propylene, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, and the like.
The content of the reactive carbonyl group in the PVA having a reactive carbonyl group is preferably 0.5 to 20 mol% of the whole polymer, and more preferably 2 to 10 mol% in view of water resistance. If the content is less than 2 mol%, the water resistance is practically insufficient, and if it exceeds 10 mol%, no further improvement in water resistance is observed and the cost increases. Moreover, 300-3,000 are preferable and, as for the polymerization degree of PVA which has the said reactive carbonyl group, 500-2,200 are more preferable. The saponification degree of the PVA having a reactive carbonyl group is preferably 80% or more.

The hydrazide compound is not particularly limited as long as it has a hydrazide group, and can be appropriately selected according to the purpose. , Adipic acid dihydrazide, azelaic acid hydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, maleic acid dihydrazide, fumaric acid hydrazide, itaconic acid dihydrazide, benzoic acid hydrazide, glutaric acid dihydrazide, diglycolic acid hydrazide dihydrazide dihydric acid dihydrazide Examples include isophthalic acid hydrazide, terephthalic acid dihydrazide, 2,7-naphthoic acid dihydrazide, and polyacrylic acid hydrazide. These may be used individually by 1 type and may use 2 or more types together. Among these hydrazide compounds, adipic acid dihydrazide is preferable from the viewpoint of water resistance and safety.
5-40 mass parts is preferable with respect to 100 mass parts of polyvinyl alcohol which has the said reactive carbonyl group, and, as for content of the said hydrazide compound, 15-25 mass parts is more preferable.

  The protective layer preferably contains a filler. The filler is preferably basic, and examples thereof include aluminum hydroxide, calcium carbonate, talc, alkaline silicic acid, etc., but aluminum hydroxide and carbonic acid are suitable for matching with the thermal head (debris adhesion). Calcium is preferred, and aluminum hydroxide is particularly preferred in view of pH control due to moderate water solubility. Known fillers can be used as the filler contained in the thermosensitive coloring layer, and examples thereof include calcium carbonate, zinc oxide, aluminum oxide, titanium dioxide, silica, aluminum hydroxide, barium sulfate, talc, kaolin, alumina, Examples include inorganic pigments such as clay or known organic pigments, but are not limited thereto. Considering water resistance (water peeling resistance), silica, kaolin and alumina which are acidic pigments (showing acidity in an aqueous solution) are preferable, and silica is particularly preferable from the viewpoint of color density.

The protective layer is not particularly limited and can be formed by a generally known method. For example, a protective layer coating solution is prepared by a conventional method, and the protective layer is coated on the recording layer. Can be formed.
There is no restriction | limiting in particular in the thickness of the said protective layer, Although it can select suitably according to the objective, 1.0-7.0 micrometers is preferable.

  If necessary, an intermediate layer or the like can be provided between the support and the heat-sensitive recording layer. As the components constituting these layers, the above fillers, binders, heat-fusible substances, surfactants and the like can be used.

  The heat-sensitive adhesive material of the present invention can be provided with a pre-printed layer according to the purpose on the opposite surface (recording layer surface) of the heat-sensitive adhesive layer. It can also be provided in the adhesive layer. Both printing methods include general printing methods such as UV printing, EB printing, and flexographic printing. As a printing ink, for example, UV curable ink is used as an optimum ink for thermal recording paper because it is quick-drying. Examples of the UV curable ink (UV ink) include UV RNC, UV NVR, UV SOYA, and UV SOYA-RNC UV inks manufactured by T & K TOKA; FD FL UV ink manufactured by Toyo Ink Manufacturing Co., Ltd. It is done.

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, the heat-sensitive adhesive material is preliminarily used in the heat-sensitive adhesive material. A cut may be formed. 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 label sheet form, a roll form etc. are mentioned suitably.
Among these, from the viewpoint of convenience, storage location, and handleability, it is preferable to wind it around a cylindrical core material and to store it by winding it into a long roll.

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, resin plates such as acrylic, polyethylene terephthalate (PET), polystyrene and nylon, metal plates such as SUS and aluminum, paper products such as envelopes and cardboard, polyolefin wraps, polyvinyl chloride Preferable examples include wraps made of polyethylene and non-woven fabric made of polyethylene (such as envelopes).
Among these, it is advantageous in that it has a strong adhesive force to rough surface adherends such as cardboard and polyolefin wrap and 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, the activation method using a thermal head is preferable, and the following thermal activation method for the heat-sensitive adhesive material of the present invention is particularly preferable. In this case, it is possible to perform recording on the thermosensitive recording layer and thermal activation of the thermosensitive adhesive layer by heating both surfaces of the thermosensitive adhesive material using an existing thermal recording printer device. It is advantageous.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example at all.

(Preparation Example 1-1)
-Preparation of under layer coating solution [A-1 solution]-
Amorphous silica (made by Nippon Silica Kogyo Co., Ltd., Nipgel AZ-200, solid content concentration 97% by mass, volume average particle size 2.5 μm, oil absorption 320 ml / 100 g) 4.6 parts by mass, 2-ethylhexyl acrylate-methyl A copolymer of methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, manufactured by Showa Polymer Co., Ltd.), 24.4 parts by mass, surfactant (Dapro W-77) The mixture consisting of 0.1 part by mass and 70.9 parts by mass of water was stirred and dispersed to prepare an under layer coating liquid [A-1 liquid].

(Preparation Example 1-2)
-Preparation of under layer coating solution [A-2 solution]-
Plastic spherical hollow particles (1) (acrylonitrile-vinylidene chloride-methyl methacrylate copolymer, solid content concentration 41% by mass, volume average particle size 3.6 μm, hollow rate 90%) 14.6 parts by mass, 2-ethylhexyl acrylate -Methyl methacrylate-styrene copolymer (glass transition temperature (Tg) =-65 [deg.] C., solid content concentration 55.4% by mass, manufactured by Showa Polymer Co., Ltd.) 21.7 parts by mass, surfactant (Dapro W -77, manufactured by Elementis Japan Co., Ltd.) A mixture of 0.1 part by mass and 63.6 parts by mass of water was stirred and dispersed to prepare an under layer coating solution [A-2 solution].

(Preparation Example 1-3)
-Preparation of under layer coating solution [A-3 solution]-
Plastic spherical hollow particles (2) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid concentration 33% by mass, volume average particle size 3.0 μm, hollow rate 91%) 18.2 parts by mass, n-butyl Acrylate-methyl acrylate copolymer (glass transition temperature (Tg) = − 62 ° C., solid content concentration 50 mass%, manufactured by JSR) 24.0 parts by mass, surfactant (Dapro W-77, Elementis Japan) (Product) A mixture of 0.1 part by mass and 57.7 parts by mass of water was stirred and dispersed to prepare an underlayer coating solution [A-3 solution].

(Preparation Example 1-4)
-Preparation of under layer coating solution [A-4 solution]-
Plastic spherical hollow particles (3) (acrylonitrile-vinylidene chloride-methyl methacrylate copolymer, solid content concentration 41% by mass, volume average particle size 3.2 μm, hollow rate 70%) 22.0 parts by mass, 2-ethylhexyl acrylate -Methyl methacrylate-styrene copolymer (glass transition temperature (Tg) =-5 ° C., solid content concentration 55.4% by mass, Showa Polymer Co., Ltd.) 16.2 parts by mass, surfactant (Dapro W -77, manufactured by Elementis Japan Co., Ltd.) A mixture of 0.1 part by mass and 61.7 parts by mass of water was stirred and dispersed to prepare an under layer coating solution [A-4 solution].

(Preparation Example 1-5)
-Preparation of under layer coating solution [A-5 solution]-
Plastic spherical hollow particles (4) (acrylonitrile-vinylidene chloride-methyl methacrylate copolymer, solid content concentration 40% by mass, volume average particle size 1.5 μm, hollow rate 50%) 30.0 parts by mass, 2-ethylhexyl acrylate -N-butyl acrylate-styrene copolymer (glass transition temperature (Tg) = -30 ° C, solid content concentration 50.0% by mass, manufactured by Showa Polymer Co., Ltd.) 12.0 parts by mass, surfactant (Dapro W-77, manufactured by Elementis Japan Co., Ltd.) 0.1 parts by mass and 57.9 parts by mass of water were stirred and dispersed to prepare an under layer coating solution [A-5 solution].

(Preparation Example 1-6)
-Preparation of under layer coating solution [A-6 solution]-
Plastic spherical hollow particles (2) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid content concentration 33% by mass, volume average particle size 3.0 μm, hollow rate 91%) 6.1 parts by mass, ethylene-acetic acid Vinyl-acrylic copolymer (glass transition temperature (Tg) = − 20 ° C., solid content 53 mass%, manufactured by Sumika Chemtex Co., Ltd.) 30.2 parts by mass, surfactant (Dapro W-77, Elementis) The mixture which consists of 0.1 mass part (made by Japan company) and 63.6 mass parts of water was stirred and disperse | distributed, and the underlayer coating liquid [A-6 liquid] was prepared.

(Preparation Example 1-7)
-Preparation of under layer coating solution [A-7 solution]-
Plastic spherical hollow particles (5) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid content concentration 33% by mass, volume average particle size 6.0 μm, hollow rate 91%) 27.3 parts by mass, 2-ethylhexyl Copolymer of acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, manufactured by Showa Polymer Co., Ltd.) 16.3 parts by mass, surfactant (Dapro A mixture comprising 0.1 part by mass of W-77 (produced by Elementis Japan) and 56.3 parts by mass of water was stirred and dispersed to prepare an under layer coating solution [A-7 solution].

(Preparation Example 1-8)
-Preparation of under layer coating solution [A-8 solution]-
Plastic spherical hollow particles (2) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid concentration 33% by mass, volume average particle size 3.0 μm, hollow rate 91%) 18.2 parts by mass, n-butyl Copolymer of acrylate-methyl acrylate-methyl methacrylate (glass transition temperature (Tg) = 0 ° C., solid content concentration 55% by mass, manufactured by JSR) 21.8 parts by mass, surfactant (Dapro W-77, Elemente) A mixture comprising 0.1 part by mass of Tis Japan Co., Ltd. and 59.9 parts by mass of water was stirred and dispersed to prepare an under layer coating solution [A-8 solution].

(Preparation Example 1-9)
-Preparation of under layer coating solution [A-9 solution]-
Plastic spherical hollow particles (2) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid content concentration 33% by mass, volume average particle size 3.0 μm, hollow rate 91%) 44.6 parts by mass, n-butyl Acrylate-methyl acrylate copolymer (glass transition temperature (Tg) = − 62 ° C., solid content 50 mass%, manufactured by JSR) 6.5 parts by mass, surfactant (Dapro W-77, Elementis Japan) (Product made) The mixture which consists of 0.1 mass part and 48.8 mass parts of water was stirred and disperse | distributed, and the underlayer coating liquid [A-9 liquid] was prepared.

(Preparation Example 1-10)
-Preparation of under layer coating solution [A-10 solution]-
Plastic spherical hollow particles (2) (acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer, solid content concentration 33% by mass, volume average particle size 3.0 μm, hollow rate 91%) 3 parts by mass, n-butyl acrylate- Copolymer of methyl acrylate (glass transition temperature (Tg) = − 62 ° C., solid content concentration 50% by mass, manufactured by JSR) 34.0 parts by mass, surfactant (Dapro W-77, manufactured by Elementis Japan) A mixture composed of 0.1 part by mass and 62.9 parts by mass of water was stirred and dispersed to prepare an under layer coating solution [A-10 solution].

(Preparation Example 1-11)
-Under layer coating solution [A-11 solution]-
Copolymer of 2-ethylhexyl acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, Showa Polymer Co., Ltd.) 90.3 parts by mass, surface activity A mixture of 0.1 parts by weight of an agent (Dapro W-77, manufactured by Elementis Japan) and 9.6 parts by weight of water was stirred and dispersed to prepare an underlayer coating solution [A-11 solution]. .

(Preparation Example 1-12)
-Preparation of under layer coating solution [A-12 solution]-
Plastic spherical hollow particles (1) (acrylonitrile-vinylidene chloride-methyl methacrylate copolymer, solid content concentration 41% by mass, volume average particle size 3.6 μm, hollow rate 90%) 23.4 parts by mass, styrene-butadiene copolymer A mixture comprising 10 parts by mass of polymer latex (glass transition temperature (Tg) = + 4 ° C.), 0.1 part by mass of a surfactant (Dapro W-77, manufactured by Elementis Japan), and 66.5 parts by mass of water. The mixture was stirred and dispersed to prepare an under layer coating solution [A-12 solution].

(Preparation Example 2-1)
-Preparation of hot melt material dispersion [B-1 solution]-
2- (2′-hydroxy-3′-t-butyl-5′-methylphenyl) -5-chlorobenzotriazole (melting point (mp) = 138 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) An average particle diameter of 1.0 μm is obtained from a mixture of 6.7 parts by mass, surfactant (Olfin PD-001, manufactured by Nissin Chemical Industry Co., Ltd.), 0.2 parts by mass, and water, 53.1 parts by mass. Thus, it was dispersed using a sand mill to prepare a hot-melt material dispersion [B-1 solution].

(Preparation Example 2-2)
-Preparation of hot-melting substance dispersion liquid [B-2 liquid]-
2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) -5-chlorobenzotriazole (melting point (mp) = 152 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) An average particle diameter of 1.0 μm is obtained from a mixture of 6.7 parts by mass, surfactant (Olfin PD-001, manufactured by Nissin Chemical Industry Co., Ltd.), 0.2 parts by mass, and water, 53.1 parts by mass. Thus, it was dispersed using a sand mill to prepare a heat-meltable substance dispersion liquid [B-2 liquid].

(Preparation Example 2-3)
-Preparation of hot melt material dispersion [B-3 solution]-
2- (2′-hydroxy-3 ′, 5′-di-t-amylphenyl) benzotriazole (melting point (mp) = 80 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) 6.7 masses Part, a surfactant (Olfin PD-001, manufactured by Nissin Chemical Industry Co., Ltd.) 0.2 part by mass, and a mixture of 53.1 parts by mass of water and a sand mill so that the average particle size is 1.0 μm. It was used and dispersed to prepare a hot-melt material dispersion [B-3].

(Preparation Example 2-4)
-Preparation of hot melt material dispersion [B-4 solution]-
Benzyl p-hydroxybenzoate (melting point (mp) = 113-115 ° C.) 40.0 parts by mass, 6.7 parts by mass of polyvinyl alcohol (30% by mass aqueous solution), surfactant (Olfin PD-001, Nissin Chemical Industry) (Made by Co., Ltd.) A mixture of 0.2 part by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.0 μm. Liquid] was prepared.

(Preparation Example 2-5)
-Hot melt material dispersion [B-5 solution]-
n-propyl p-hydroxybenzoate (melting point (mp) = 99-100 ° C.) 40.0 parts by mass, 6.7 parts by mass of polyvinyl alcohol (30% by mass aqueous solution), surfactant (Orphine PD-001 (Nissin) (Chemical Industry Co., Ltd.) A mixture of 0.2 part by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.0 μm, and a hot-melt material dispersion [B −5 solution] was prepared.

(Preparation Example 2-6)
-Preparation of Hot Melt Dispersion Liquid [B-6 Liquid]-
Anisoin (melting point (mp) = 99-100 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) 6.7 parts by mass, surfactant (Olfin PD-001, manufactured by Nissin Chemical Industry Co., Ltd.) 0 A mixture of .2 parts by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.0 μm to prepare a hot-melt material dispersion [B-6]. .

(Preparation Example 2-7)
-Preparation of hot melt dispersion (B-7 solution)-
1-dihydroxy-2-naphthoic acid phenyl (melting point (mp) = 94-96 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) 6.7 parts by mass, surfactant (Orphine PD-001 (day A mixture of 0.2 parts by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.0 μm, and a hot-melt material dispersion liquid [B-7 solution] was prepared.

(Preparation Example 2-8)
-Preparation of Hot Melt Substance Dispersion [Liquid B-8]-
3-hydroxyphenyl benzoate (melting point (mp) = 135 ° C.) 40.0 parts by mass, 6.7 parts by mass of polyvinyl alcohol (30% by mass aqueous solution), surfactant (Orphine PD-001, Nissin Chemical Industry Co., Ltd.) A mixture consisting of 0.2 part by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.0 μm, and a hot-melt material dispersion [B-8 Liquid] was prepared.

(Preparation Example 3-1)
-Preparation of eutectic agent dispersion [C-1 solution]-
Succinic acid di-p-methylbenzyl ester (melting point (mp) = 101 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) 6.7 parts by mass, surfactant (Orphine PD-001, Nissin Chemical Industry) (Made by Co., Ltd.) A mixture of 0.2 part by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.2 μm, and a eutectic agent dispersion [C-1 Liquid] was prepared.

(Preparation Example 3-2)
-Preparation of eutectic agent dispersion [C-2 solution]-
Succinic acid di-p-methylbenzyl ester (melting point (mp) = 80 ° C.) 40.0 parts by mass, polyvinyl alcohol (30% by mass aqueous solution) 6.7 parts by mass, surfactant (Orphine PD-001, Nissin Chemical Industry) (Made by Co., Ltd.) A mixture of 0.2 part by mass and 53.1 parts by mass of water was dispersed using a sand mill so that the average particle size was 1.2 μm, and a eutectic agent dispersion [C-2 Liquid] was prepared.

(Preparation Example 4-1)
-Preparation of thermosensitive adhesive coating solution [D-1 solution]-
Copolymer of n-butyl acrylate-methyl acrylate (glass transition temperature (Tg) = − 62 ° C., solid concentration 50 mass%, manufactured by JSR) 10 parts by mass, polymerized rosin emulsion (softening point 145 ° C., nonvolatile content 50 %) A mixture of 6 parts by mass, 37.5 parts by mass of the heat-fusible substance dispersion [Liquid B-1] and 7 parts by mass of the eutectic agent dispersion [Liquid C-1] is uniformly mixed to obtain heat sensitivity. An adhesive coating solution [D-1 solution] was prepared.

(Preparation Example 4-2)
-Preparation of thermosensitive adhesive coating solution [D-2 solution]-
Copolymer of 2-ethylhexyl acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, Showa Polymer Co., Ltd.) 9 parts by mass, terpene phenol emulsion ( A mixture comprising 6 parts by mass of a softening point of 150 ° C. and a non-volatile content of 50%, 37.5 parts by mass of a hot-melt material dispersion [Liquid B-2], and 7 parts by mass of a eutectic agent dispersion [Liquid C-2]. Were mixed uniformly to prepare a heat-sensitive adhesive coating solution [D-2 solution].

(Preparation Example 4-3)
-Preparation of heat-sensitive adhesive coating solution [D-3 solution]-
Copolymer of n-butyl acrylate-methyl acrylate (glass transition temperature (Tg) = − 62 ° C., solid concentration 50 mass%, manufactured by JSR) 10 parts by mass, polymerized rosin emulsion (softening point 145 ° C., nonvolatile content 50 %) 6 parts by mass, 19 parts by mass of the hot melt material dispersion [B-1 liquid], 19 parts by mass of the hot melt material dispersion [B-2 liquid], and the eutectic agent dispersion [C-1 liquid]. A mixture consisting of 7 parts by mass was uniformly mixed to prepare a heat-sensitive adhesive coating solution [D-3 solution].

(Preparation Example 4-4)
-Preparation of heat-sensitive adhesive coating solution [D-4 solution]-
Copolymer of 2-ethylhexyl acrylate-n-butyl acrylate-styrene (glass transition temperature (Tg) =-30 ° C., solid content concentration 50.0% by mass, Showa Polymer Co., Ltd.) 10 parts by mass, terpene phenol emulsion (Softening point 150 ° C., non-volatile content 50%) 6 parts by mass, 19 parts by mass of hot-melting substance dispersion [B-2 liquid], 19 parts by mass of hot-melting substance dispersion [B-3 liquid], and eutectic A mixture of 7 parts by mass of the agent dispersion [C-1 solution] was uniformly mixed to prepare a thermosensitive adhesive coating solution [D-4 solution].

(Preparation Example 4-5)
-Preparation of thermosensitive adhesive coating solution [D-5 solution]-
Copolymer of 2-ethylhexyl acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 5 ° C., solid content concentration 55.4 mass%, Showa Polymer Co., Ltd.) 9 mass parts, polymerized rosin emulsion ( A mixture of 6 parts by mass of softening point 145 ° C., non-volatile content 50%) and 37.5 parts by mass of the heat-meltable substance dispersion (Liquid B-4) is uniformly mixed to form a heat-sensitive adhesive coating solution [D −5 solution] was prepared.

(Preparation Example 4-6)
-Preparation of heat-sensitive adhesive coating solution [D-6 solution]-
Copolymer of ethylene-vinyl acetate-acrylic (glass transition temperature (Tg) = − 20 ° C., solid content concentration 53 mass%, manufactured by Sumika Chemtex Co., Ltd.) 9.4 parts by mass, terpene phenol emulsion (softening point 150 ° C. , Non-volatile content 50%) 6 parts by mass, and a mixture of 37.5 parts by mass of the heat-fusible substance dispersion (liquid B-5) were uniformly mixed to obtain a heat-sensitive adhesive coating liquid [liquid D-6]. Was prepared.

(Preparation Example 4-7)
-Preparation of thermosensitive adhesive coating solution [D-7 solution]-
Copolymer of 2-ethylhexyl acrylate-n-butyl acrylate-styrene (glass transition temperature (Tg)) =-30 ° C., solid content concentration 50.0% by mass, Showa Polymer Co., Ltd. 10 parts by mass, polymerized rosin 6 parts by mass of emulsion (softening point 145 ° C., 50% non-volatile content), 19 parts by mass of hot-melting substance dispersion [liquid B-4], and 19 parts by mass of hot-melting substance dispersion [liquid B-5] The mixture was uniformly mixed to prepare a heat-sensitive adhesive coating solution [D-7 solution].

(Preparation Example 4-8)
-Preparation of thermosensitive adhesive coating solution [D-8 solution]-
Copolymer of n-butyl acrylate-methyl acrylate (glass transition temperature (Tg) = − 62 ° C., solid content concentration 50% by mass, manufactured by JSR) 10 parts by mass, terpene phenol emulsion (softening point 150 ° C., nonvolatile content 50) %) And a mixture of 37.5 parts by mass of a heat-meltable substance dispersion (B-6 liquid) were uniformly mixed to prepare a heat-sensitive adhesive coating liquid [D-8 liquid].

(Preparation Example 4-9)
-Preparation of heat-sensitive adhesive coating solution [D-9 solution]-
Copolymer of 2-ethylhexyl acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, Showa Polymer Co., Ltd.) 9 parts by mass, terpene phenol emulsion ( A mixture comprising 6 parts by mass of a softening point of 150 ° C. and a non-volatile content of 50%) and 37.5 parts by mass of a heat-meltable substance dispersion (B-7 solution) was uniformly mixed to produce a heat-sensitive adhesive coating solution [D −9 solution] was prepared.

(Preparation Example 4-10)
-Preparation of thermosensitive adhesive coating solution [D-10 solution]-
Copolymer of 2-ethylhexyl acrylate-methyl methacrylate-styrene (glass transition temperature (Tg) = − 65 ° C., solid content concentration 55.4% by mass, Showa Polymer Co., Ltd.) 9 parts by mass, terpene phenol emulsion ( A mixture comprising 6 parts by mass of a softening point of 150 ° C. and a non-volatile content of 50% and 37.5 parts by mass of a heat-fusible substance dispersion [Liquid B-8] is uniformly mixed to form a heat-sensitive adhesive coating solution [D −10 solution] was prepared.

(Preparation Example 4-11)
-Preparation of thermosensitive adhesive coating solution [D-11 solution]-
Copolymer of 2-ethylhexyl acrylate-n-butyl acrylate-styrene (glass transition temperature (Tg) =-30 ° C., solid content concentration 50.0% by mass, Showa Polymer Co., Ltd.) 10 parts by mass, terpene phenol emulsion (Softening point 150 ° C., nonvolatile content 50%) 6 parts by mass, 19 parts by mass of hot-melting substance dispersion [B-7 liquid], 19 parts by mass of hot-melting substance dispersion [B-8 liquid], and eutectic A mixture composed of 7 parts by mass of an agent dispersion [C-1 solution] was uniformly mixed to prepare a thermosensitive adhesive coating solution [D-11 solution].

Example 1
-Production of heat-sensitive adhesive material-
The under layer coating solution [A-1] on the side of the single-sided coated paper (OK Adonis Rough, manufactured by Oji Paper Co., Ltd.) having a basis weight of 80 g / m ² as the support has a dry adhesion amount of 15 g. / M ² was applied and dried to form an under layer. A heat-sensitive adhesive layer coating solution [D-1] was applied on the under layer so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer. Thus, a heat-sensitive adhesive material was produced.

(Example 2)
-Production of heat-sensitive adhesive material-
<Formation of ink receiving layer of hot melt transfer recording paper>
High-quality paper having a basis weight of 80 g / m ² as a support, aluminum hydroxide particles having a volume average particle diameter of 0.4 to 0.5 μm as a pigment component, and styrene-maleic anhydride copolymer alkali salt resin as a binder resin A coating solution having a filler / binder resin composition ratio of 1 / 0.2 was prepared. This coating solution was uniformly applied with a wire bar to provide an ink image-receiving layer, thereby preparing an ink-receiving sheet for hot melt transfer.

Next, an under layer coating solution [A-2] was applied on the support surface of the obtained hot melt transfer recording paper that does not have an ink-receiving layer so that the dry adhesion amount was 5 g / m ^2. And dried to form an under layer. A heat-sensitive adhesive layer coating solution [D-2] was applied onto the under layer so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer. Thus, a heat-sensitive adhesive material was produced.

(Example 3)
-Production of heat-sensitive adhesive material-
<Formation of thermal recording layer>
-Preparation of non-foaming heat insulating layer forming coating solution [E solution]-
Fine hollow particle dispersion (copolymer resin mainly composed of vinylidene chloride-acrylonitrile, solid content concentration 32% by mass, average particle size 3.6 μm, hollowness 92%) 30 parts by mass, styrene-butadiene copolymer latex (glass) A mixture comprising 10 parts by mass of a transition temperature (Tg) = + 4 ° C., 0.1 part by mass of a surfactant (Dapro W-77, manufactured by Elementis Japan), and 60 parts by mass of water was stirred and dispersed, and non-foamed Heat insulating layer forming coating solution [E solution] was prepared.

-Preparation of color former dispersion liquid [F liquid]-
A mixture of 20 parts by mass of 3-di-n-butylamino-6-methyl-7-anilinofluorane, 10 parts by mass of polyvinyl alcohol (10% by mass aqueous solution), and 70 parts by mass of water was stirred and dispersed. A color former dispersion [liquid F] was prepared.

-Preparation of developer dispersion [liquid G]-
A mixture of 10 parts by mass of 4-isopropoxy-4′-hydroxydiphenylsulfone, 25 parts by mass of polyvinyl alcohol (10% by mass aqueous solution), 15 parts by mass of calcium carbonate, and 50 parts by mass of water has an average particle size. A developer dispersion [G solution] was prepared by dispersing with a sand mill so as to have a thickness of about 1.5 μm.

Next, the color developing agent dispersion solution [F solution]: the developer dispersion solution [G solution] = 1: 8 (mass ratio) is mixed and stirred to prepare a thermosensitive coloring layer coating solution [solution H]. did. The non-foaming heat insulating layer-forming coating solution [E solution] is applied to the surface of a single-side coated paper having an average basis weight of 80 g / m ² so that the mass after drying is 4 g / m ² , dried and non-foamed. A heat insulating layer was provided. On the non-foaming heat insulating layer, the color former dispersion liquid [F] was applied and dried to a mass of 5 g / m ² after drying to provide a heat sensitive recording layer. Thereafter, a super-calender treatment was performed so that the Oken-type smoothness was 2000 seconds to produce a heat-sensitive recording paper having a heat-sensitive recording layer.

Next, an under layer coating solution [A-3] is applied on the support surface on the side of the obtained thermal recording paper that does not have a thermal recording layer so that the dry adhesion amount is 4 g / m ² and dried. An under layer was formed. A heat-sensitive adhesive layer coating solution [D-3] was applied onto the under layer so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer. Thus, a heat-sensitive adhesive material was produced.

Example 4
-Production of heat-sensitive adhesive material-
In Example 3, the under layer coating solution [A-4] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 3 except that [D-3] was applied so that the dry adhesion amount was 15 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 5)
-Production of heat-sensitive adhesive material-
In Example 3, the under layer coating solution [A-5] was applied so that the dry adhesion amount was 5 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 3 except that [D-4] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 6)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-6] was applied so that the dry adhesion amount was 5 g / m ² , dried to form an under layer, and the thermosensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-5] was applied to a dry adhesion amount of 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 7)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-6] was applied so that the dry adhesion amount was 5 g / m ² , dried to form an under layer, and the thermosensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-6] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 8)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-6] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the thermosensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-3] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

Example 9
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-7] was applied so that the dry adhesion amount was 5 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-3] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 10)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-9] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-7] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 11)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-9] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was prepared in the same manner as in Example 1 except that [D-8] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 12)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-10] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-3] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 13)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-3] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-9] was applied to a dry adhesion amount of 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 14)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-10] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-10] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 15)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-3] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-11] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Example 16)
-Production of heat-sensitive adhesive material-
In Example 3, a protective layer coating solution having the following composition was applied onto the heat-sensitive recording layer so that the dry adhesion mass was 3 g / m ² and dried to provide a calendar so that the smoothness of the protective layer surface was 5000 seconds. A heat-sensitive adhesive material was produced in the same manner as in Example 3 except that the treatment was performed.
<Preparation of protective layer coating solution>
40 parts by mass of aluminum hydroxide dispersion (solid content 50% by mass), 6 parts by mass of zinc stearate dispersion (solid content 30% by mass), 1 part of dioctylsulfosuccinic acid aqueous solution (solid content 5% by mass), and diacetone group PVA (diacetone monomer unit content 4% by mass, polymerization degree 1600, saponification degree 98%, manufactured by Shin-Etsu Chemical Co., Ltd.) 10% by mass aqueous solution 200 parts by mass, adipic acid hydrazide (crosslinking agent) aqueous solution (solid content 10% by mass) A composition comprising 40 parts by mass and 43 parts by mass of water was mixed to prepare a protective layer coating solution.

(Comparative Example 1)
-Production of heat-sensitive adhesive material-
In Example 1, the heat-sensitive adhesive layer coating solution [D-1] was applied on the surface of the support that does not have the coating layer so that the dry adhesion amount was 10 g / m ^2, and dried to heat-sensitive. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that an adhesive layer was formed.

(Comparative Example 2)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-8] was applied so that the dry adhesion amount was 10 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-1] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Comparative Example 3)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-11] was applied so that the dry adhesion amount was 15 g / m ² , dried to form an under layer, and the thermosensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-1] was applied so that the dry adhesion amount was 10 g / m ² and dried to form a heat-sensitive adhesive layer.

(Comparative Example 4)
-Production of heat-sensitive adhesive material-
In Example 1, the under layer coating solution [A-12] was applied so that the dry adhesion amount was 4 g / m ² , dried to form an under layer, and the heat-sensitive adhesive layer coating solution was formed on the under layer. A heat-sensitive adhesive material was produced in the same manner as in Example 1 except that [D-3] was applied so that the dry adhesion amount was 15 g / m ² and dried to form a heat-sensitive adhesive layer.

  Next, for the obtained Examples 1 to 16 and Comparative Examples 1 to 4, the immediately following adhesive force, the after-time adhesive force, and the blocking property were evaluated as follows. The results are shown in Table 3, Table 4, and Table 5.

<Measurement of adhesive strength immediately after>
Each heat-sensitive adhesive material is cut into a rectangle of 25 mm × 150 mm, and using a thermal printing apparatus (manufactured by Okura Electric Co., Ltd., TH-PMD), head conditions: each energy 0.35 mJ / dot, 0.45 mJ / dot, The heat-sensitive adhesive material was thermally activated under the conditions of 0.5 mJ / dot, printing speed: 4 ms / line, and platen pressure: 6 kgf / line. Subsequently, it was affixed to the adherend (polyolefin wrap and corrugated cardboard) in the longitudinal direction with a 2 kg pressure rubber roller, and peeled after 1 hour 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 (MODEL DPS-5, manufactured by IMADA), and the data was read and averaged at intervals of 0.1 seconds. The unit is gf / 25 mm. This test was performed in a room temperature environment (23 ° C., 65%).

<Measurement of adhesive strength over time>
Each heat-sensitive adhesive material is cut into a rectangle of 25 mm × 150 mm, and using a heat-sensitive printing apparatus (manufactured by Okura Electric Co., Ltd., TH-PMD), head conditions: each energy 0.5 mJ / dot, printing speed: 4 ms / line The heat-sensitive adhesive material was thermally activated under the conditions of platen pressure: 6 kgf / line. Subsequently, it was affixed to the adherend (polyolefin wrap and cardboard) in the longitudinal direction with a 2 kg pressure rubber roller, and was peeled after one week under 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 (MODEL DPS-5, manufactured by IMADA), and the data was read and averaged at intervals of 0.1 seconds to show the numerical values. The unit is gf / 25 mm. This test was performed in a room temperature environment (23 ° C., 65%).

[Evaluation criteria for adhesive strength of PO wrap]
◎: 1500 gf / 25 mm or more ○: 1000 gf / 25 mm or more and less than 1500 gf / 25 mm Δ: 700 gf / 25 mm or more and less than 1000 gf / 25 mm x: less than 700 gf / 25 mm

[Evaluation criteria for cardboard adhesive strength]
◎: 700 gf / 25 mm or more ○: 500 gf / 25 mm or more and less than 700 gf / 25 mm Δ: 300 gf / 25 mm or more and less than 500 gf / 25 mm x: Less than 300 gf / 25 mm

<Evaluation of blocking properties>
The surface opposite to the surface of the heat-sensitive adhesive layer in each heat-sensitive adhesive material was brought into contact, and left at a pressure of 200 gf / cm ² at 50 ° C. for 24 hours under Dry conditions. Then, after leaving at room temperature, the sample was peeled off, and the blocking property at that time was evaluated based on the rank and evaluation criteria shown in Table 2 below.

〔Evaluation criteria〕
: Rank 10
○: Rank 8-9
Δ: Rank 6-7
×: Rank 5 or lower

From the results of Tables 3 to 5, Comparative Example 1 having no under layer, Comparative Example 2 in which the glass transition temperature of the thermoplastic resin in the under layer is 0 ° C., and the glass transition temperature of the thermoplastic resin in the under layer are +4. It is recognized that Comparative Example 4 at 0 ° C. is inferior in adhesive properties, particularly adhesive properties over time. Moreover, it is recognized that the comparative example 3 in which an under layer does not contain a hollow filler is inferior in blocking resistance.
On the other hand, Examples 1-16 are excellent in adhesiveness, there is no fall of the adhesive force with time, and it is recognized that blocking resistance is also favorable. In Example 16, since the protective layer contains polyvinyl alcohol having a reactive carbonyl group and a hydrazide compound, it can be seen that the blocking resistance is improved.

(Example 17)
-Preparation of dispersion A-
100 parts by mass of 2- (3′-t-butyl-5′-methyl-2′-hydroxyphenyl) -5-chlorobenzotriazole, 50 parts by mass of a 10% solution of polyvinyl alcohol, and 200 parts by mass of water uniformly The mixture was mixed and pulverized to a mean particle size of 1.0 μm using a ball mill to prepare dispersion A.

-Preparation of dispersion B-
100 parts by mass of di (p-methylbenzyl) oxalate ester, 50 parts by mass of a 10% polyvinyl alcohol solution and 200 parts by mass of water are uniformly mixed and pulverized using a ball mill until the average particle size is 1.0 μm. Thus, dispersion B was prepared.

-Preparation of heat-sensitive adhesive layer coating solution C-
100 parts by mass of thermoplastic resin emulsion AP5570 (manufactured by Showa Polymer Co., Ltd., solid content 55% by mass, glass transition temperature -65 ° C.), tackifier emulsion E100 (manufactured by Arakawa Chemical Co., Ltd., solid content 50%, softening point 145 ° C. ), 540 parts by mass of dispersion A, 150 parts by mass of dispersion B, and 130 parts by mass of water were sufficiently stirred and mixed to prepare thermosensitive adhesive layer coating solution C.

−Preparation of under layer coating liquid D−
100 parts by mass of hollow particle emulsion low-pake HP-91 (Rohm & Haas, hollow ratio 50%, solid content 27.5% by mass), polymer resin emulsion AD83 (Showa Polymer Co., Ltd., main component ethylene vinyl acetate Undercoat coating liquid D was prepared by sufficiently stirring and mixing 220 parts by mass and a glass transition temperature of −2 ° C.) at a ratio of 220 parts by mass and 440 parts by mass of water. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

-Production of heat-sensitive adhesive material E-
On the opposite side of the thermal recording layer of Ricoh Co., Ltd. thermal paper type 120LCS-O (support: Yupo synthetic paper film made by Oji Yuka), the thickness after drying the underlayer coating liquid D using a wire bar is 20 After coating and drying to a thickness of 0.0 μm, the heat-sensitive adhesive layer coating solution C was applied to a thickness after drying of 15.0 μm and dried to give a heat-sensitive adhesive having a total thickness of 35.0 μm. Material E was produced.

(Example 18)
In Example 17, polymer resin emulsion AD83 (manufactured by Showa Polymer Co., Ltd., main component ethylene vinyl acetate, solid content 56 mass%, glass transition temperature -2 ° C.) used for the under layer was FREX751 (manufactured by Sumitomo Chemical Co., Ltd. A heat-sensitive adhesive material of Example 18 was produced in the same manner as in Example 17 except that the component ethylene vinyl acetate, solid content 50% by mass, and glass transition temperature -15 ° C were changed. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

(Example 19)
In Example 18, the thickness of the under layer was 9.0 μm, the thickness of the heat-sensitive adhesive layer was 6.0 μm, and the total thickness was changed to 15.0 μm. Adhesive material was produced. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

(Example 20)
In Example 18, the thickness of the under layer was 13.0 μm, the thickness of the heat-sensitive adhesive layer was 7.0 μm, and the total thickness was changed to 20.0 μm. A heat sensitive adhesive material was prepared. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

(Example 21)
In Example 18, the heat sensitivity of Example 21 was the same as Example 18 except that the thickness of the under layer was 21.0 μm, the thickness of the heat-sensitive adhesive layer was 7.0 μm, and the total thickness was 28.0 μm. An adhesive material was prepared. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

(Example 22)
In Example 21, R300 (manufactured by Matsumoto Yushi Co., Ltd., 90% hollow ratio, solid content) was prepared by submerging hollow particle emulsion low-pake HP-91 (produced by Rohm & Haas Co., Ltd., hollow ratio 50%, solid content 27.5 mass%). A heat-sensitive adhesive material of Example 22 was produced in the same manner as in Example 21 except that the content was changed to 33% by mass. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 22.2% by mass.

(Example 23)
-Preparation of under layer coating solution F-
100 parts by mass of hollow particle R300 (manufactured by Matsumoto Yushi Co., Ltd., hollow ratio 90%, solid content 33% by mass), polymer resin emulsion FREX751 (manufactured by Sumitomo Chemical Co., Ltd., main component ethylene vinyl acetate, solid content 50% by mass, glass transition) Temperature −15 ° C.) was sufficiently stirred and mixed at a ratio of 230 parts by mass and 410 parts by mass of water to prepare an underlayer coating solution F. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 28.6% by mass.
In Example 22, the heat-sensitive adhesive material of Example 23 was produced in the same manner as in Example 22 except that the under layer coating liquid was changed to the under layer coating liquid F.

(Example 24)
−Preparation of under layer coating liquid G−
100 parts by mass of hollow particle R300 (manufactured by Matsumoto Yushi Co., Ltd., hollow ratio 90%, solid content 33% by mass), polymer resin emulsion FREX751 (manufactured by Sumitomo Chemical Co., Ltd., main component ethylene vinyl acetate, solid content 50% by mass, glass transition) The mixture was sufficiently stirred and mixed at a ratio of 130 parts by mass and 260 parts by mass of water to prepare an under layer coating solution G. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 50.0% by mass.
A heat-sensitive adhesive material of Example 24 was produced in the same manner as in Example 22 except that the under layer coating solution G was changed to the under layer coating solution G in Example 22.

(Example 25)
-Preparation of under layer coating liquid H-
100 parts by mass of hollow particle R300 (manufactured by Matsumoto Yushi Co., Ltd., hollow rate 90%, solid content 33% by mass), polymer resin emulsion FREX751 (manufactured by Sumitomo Chemical Co., Ltd., main component ethylene vinyl acetate, solid content 50% by mass, glass transition The mixture was sufficiently stirred and mixed at a ratio of 60 parts by mass and 155 parts by mass of water to prepare an under layer coating liquid H. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 111.0% by mass.
A heat-sensitive adhesive material of Example 25 was produced in the same manner as in Example 22 except that the under layer coating liquid was changed to the under layer coating liquid H in Example 22.

(Example 26)
-Preparation of under layer coating liquid I-
100 parts by mass of hollow particles R300 (manufactured by Matsumoto Yushi Co., Ltd., hollow rate 90%, solid content 33% by mass), polymer resin emulsion AP5570 (manufactured by Showa Polymer Co., Ltd., solid content 55% by mass, glass transition temperature -65 ° C.) Was sufficiently mixed at a ratio of 120 parts by mass and 270 parts by mass of water to prepare an underlayer coating liquid I. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 50.0% by mass.
In Example 24, a heat-sensitive adhesive material of Example 26 was produced in the same manner as in Example 24 except that the under layer coating liquid was changed to the under layer coating liquid I.

(Example 27)
-Preparation of under layer coating liquid J-
100 parts by mass of hollow particles R300 (manufactured by Matsumoto Yushi Co., Ltd., hollow rate 90%, solid content 33% by mass), polymer resin emulsion AP5570 (manufactured by Showa Polymer Co., Ltd., solid content 55% by mass, glass transition temperature -65 ° C.) 120 parts by mass, acrylic-silicone resin emulsion US224 (manufactured by Toa Gosei Co., Ltd., solid content 40% by mass, glass transition temperature 10 ° C.) is sufficiently stirred and mixed at a ratio of 160 parts by mass and water 440 parts by mass, and an under layer is applied. Liquid J was prepared. At this time, the ratio of the polymer resin to the hollow particles of the under layer is 50.0% by mass.
In Example 26, a heat-sensitive adhesive material of Example 27 was produced in the same manner as in Example 26 except that the under layer coating liquid was changed to the under layer coating liquid J.

(Comparative Example 5)
-Preparation of under layer coating liquid K-
100 parts by mass of hollow particle emulsion low-pake HP-91 (Rohm & Haas, hollow ratio 50%, solid content 27.5% by mass), polyvinyl alcohol aqueous solution (manufactured by Kuraray Co., Ltd., solid content 30% by mass, glass transition) The mixture was sufficiently stirred and mixed at a ratio of 410 parts by mass and 240 parts by mass of water to prepare an under layer coating solution K.
A heat-sensitive adhesive material of Comparative Example 5 was produced in the same manner as in Example 17 except that the under layer coating solution was changed to the under layer coating solution K in Example 17.

(Comparative Example 6)
In Example 17, an under layer coating liquid hollow particle emulsion low-pake HP-91 (Rohm & Haas Co., Ltd., hollow ratio 50%, solid content 27.5% by mass) Almatex SPMM-47BF (Mitsui Chemicals, A heat-sensitive adhesive material of Comparative Example 6 was produced in the same manner as in Example 17 except that the hollow ratio was changed to 0% and the solid content was changed to 47.5% by mass.

(Comparative Example 7)
In Example 17, a heat-sensitive adhesive material of Comparative Example 7 was obtained in the same manner as Example 17 except that the under layer was not provided.

  About each obtained heat sensitive adhesive material, various characteristics were evaluated as follows. The results are shown in Table 6, Table 7, and Table 8.

<Thermal activation conditions>
The thermal adhesive material is 4 cm wide and 10 cm long, thermal head (manufactured by TEC, TH-0976SP) 8 dots / mm, resistance 500 Ω, all dots energized, active energy 0.30 mJ / dot, 0. Activation was performed under the conditions of 45 mJ / dot, 0.60 mJ / dot, a printing speed of 100 mm / second, and a platen pressure of 6 kgf / line. Here, a series of test temperature environmental conditions were carried out in an environment of 22 ° C. and 65% RH.

<Observation of heat shrinkability of heat-sensitive adhesive labels>
The heat-activated pressure-sensitive adhesive label of the above heat-sensitive adhesive label was visually observed and evaluated by the following rank index.
(Rank index)
○: No thermal contraction of the label is observed. △: Thermal contraction of the label is observed although it is slight. ×: Thermal contraction of the label is remarkable.

<Adhesion measurement>
The activated surface of the activated heat-sensitive adhesive material label is attached to the adherend (polyolefin wrap and cardboard) in the longitudinal direction with a 2 kg rubber roller, and after 2 minutes, a peeling angle of 180 ° C. and a peeling speed of 300 mm / Peel off under the condition of min. The average resistance value of the adhesive force at that time was indicated by a numerical value. The unit is gf / 40 mm. Here, a series of test temperature environment conditions were 22 ° C. and 65% RH environment.

[Evaluation criteria for adhesive strength of PO wrap]
◎: 1500 gf / 40 mm or more ○: 1000 gf / 40 mm or more and less than 1500 gf / 40 mm Δ: 700 gf / 40 mm or more and less than 1000 gf / 40 mm ×: less than 700 gf / 40 mm

[Evaluation criteria for cardboard adhesive strength]
A: 700 gf / 40 mm or more B: 500 gf / 40 mm or more and less than 700 gf / 40 mm Δ: 300 gf / 40 mm or more and less than 500 gf / 40 mm X: Less than 300 gf / 40 mm

<Adhesive residue>
The state of the adhesive residue adhering to the cardboard when the label attached by the adhesive force measurement was peeled off was visually observed and evaluated by the following rank index.
(Rank index)
○: No trace of adhesive residue is observed. △: Trace of adhesive residue is slightly observed. ×: Significant adhesive residue is observed.

From the results of Table 6, Table 7, and Table 8, Comparative Example 5 has a glass transition temperature of the thermoplastic resin in the under layer that is too high at 100 ° C., and Comparative Example 6 shows that the hollow filler in the under layer has a hollowness of 0% ( Since Comparative Example 7 is not provided with an under layer, the adhesiveness is inferior to those of Examples.
The evaluation at 0.30 mJ / dot of Example 17 in Table 6, the evaluation at 0.30 mJ / dot of Example 17 in Table 7, and the evaluation at 0.30 mJ / dot of Example 18 in Table 7 This is because the heating energy of the thermal head is not optimized, which is clear from the results of the thermal head heating energy of 0.45 mJ / dot and 0.60 mJ / dot. .
In addition, the evaluation of the film shrinkage at 0.60 mJ / dot in Examples 17 to 22 in Table 8 is poor because the heating energy of the thermal head is not optimized. The heating energy of the head is apparent from the results of 0.45 mJ / dot and 0.60 mJ / dot.
Accordingly, the evaluation results of the heat-sensitive adhesive materials of Examples 17 to 27 slightly vary depending on the heating method (activation method) conditions. However, the heat-sensitive adhesive materials of Examples 17 to 27 were compared with Comparative Examples 5 to 7 when the heating energy of the thermal head, which is a substantially optimized heating condition, was evaluated at 0.45 mJ / dot. Even when synthetic paper is used, it is recognized that there is no film shrinkage and no adhesive residue, and that it has excellent adhesion to rough surface adherends such as cardboard and polyolefin wrap.

The heat-sensitive adhesive material of the present invention has strong adhesion to rough surface adherends such as corrugated cardboard and polyolefin wrap, has little decrease in adhesion over time, can be thermally activated with low energy, and is resistant to blocking. In particular, even when synthetic paper or plastic film is used as the support, the heat-sensitive adhesive layer does not fall off during thermal activation, and the shrinkage wrinkle of the support can be prevented. Since the rest can be improved, it is used widely, for example, for industrial, commercial, and household purposes.

Claims (22)

A support, and at least an under layer and a heat-sensitive adhesive layer on the one surface of the support in this order;
The under layer contains a thermoplastic resin having a glass transition temperature (Tg) of −70 ° C. or more and less than 0 ° C. and a hollow filler,
The thermoplastic resin is at least one selected from an acrylic ester copolymer, a methacrylic ester copolymer, and an ethylene-vinyl acetate copolymer.
(However, among the heat-sensitive adhesive materials, between the heat-sensitive adhesive layer and the support,
Acrylic ester copolymer, methacrylic ester copolymer, acrylic ester-methacrylic ester copolymer, acrylic ester-styrene copolymer, acrylic ester-methacrylic ester-styrene copolymer, and ethylene- A layer consisting only of at least one resin of vinyl acetate copolymer, or
Excluding those having a layer consisting only of a resin having a 100% modulus of 35 kgf / cm ² or less as defined in JIS K6251 . ) The heat-sensitive adhesive layer contains a thermoplastic resin, a tackifier, and a hot-melt material,
The heat-sensitive adhesive material according to claim 1, wherein the thermoplastic resin is at least one selected from an acrylic ester copolymer, a methacrylic ester copolymer, and an ethylene-vinyl acetate copolymer.   The thermoplastic resin in the under layer is an acrylic ester-methacrylic ester copolymer, an acrylic ester-styrene copolymer, an acrylic ester-methacrylic ester-styrene copolymer, and an ethylene-vinyl acetate copolymer. The heat-sensitive adhesive material according to claim 1, which is at least one selected.   The hollow filler in the under layer is a spherical hollow particle having a volume average particle diameter of 2.0 to 5.0 µm, and the hollow ratio of the spherical hollow particle is 70% or more. Heat sensitive adhesive material.   The material of the spherical hollow particles is a plastic, and the plastic is at least one selected from acrylonitrile-vinylidene chloride-methyl methacrylate copolymer and acrylonitrile-methacrylonitrile-isobornyl methacrylate copolymer. The heat-sensitive adhesive material described in 1. Mass ratio of the thermoplastic resin and the hollow filler in the under layer, heat-sensitive adhesive according to any one of the thermoplastic resin 1 part by weight of claim 1, wherein a hollow filler 0.1-2 parts by mass with respect to 5 material.   The heat-sensitive property according to any one of claims 1 to 6, wherein a mixing mass ratio of the hollow filler and the thermoplastic resin in the under layer (hollow filler: thermoplastic resin) is 1: 0.5 to 1: 3.0. Adhesive material.   The heat-sensitive property according to any one of claims 1 to 6, wherein a mixing mass ratio (hollow filler: thermoplastic resin) of the hollow filler and the thermoplastic resin in the under layer is 1: 6.0 to 1: 10.0. Adhesive material.   The thermoplastic resin in the heat-sensitive adhesive layer is an acrylic ester-methacrylic ester copolymer, an acrylic ester-styrene copolymer, an acrylic ester-methacrylic ester-styrene copolymer, and an ethylene-vinyl acetate copolymer. The heat-sensitive adhesive material according to any one of claims 2 to 8, which is at least one selected from coalescence. The heat-sensitive adhesive material according to any one of claims 2 to 9, wherein the heat-meltable substance in the heat-sensitive adhesive layer is a benzotriazole compound represented by the following structural formula (1).
However, in the structural formula (1), R ¹ and R ² may be the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an α, α-dimethylbenzyl group. . X represents a hydrogen atom or a halogen atom. The heat-sensitive adhesive material according to any one of claims 2 to 10, wherein the heat-meltable substance in the heat-sensitive adhesive layer is a hydroxybenzoic acid ester compound represented by the following structural formula (2).
However, in the structural formula (2), R ³ represents any of an alkyl group, an alkenyl group, an aralkyl group, and an aryl group, and these may be further substituted with a substituent. The heat-sensitive adhesive material according to any one of claims 2 to 11, wherein the heat-meltable substance in the heat-sensitive adhesive layer is a compound represented by any one of the following structural formulas (3), (4), and (5). .
However, in the structural formula (3), R ⁴ and R ⁵ may be the same as or different from each other, and represent an alkyl group or an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.
However, in the structural formula (4), R ⁶ represents any one of a hydrogen atom, a halogen atom, an alkyl group, and an alkoxy group. Y represents a hydrogen atom or a hydroxyl group.
In the Structural Formula (5), R ⁷ represents any one of hydrogen atom, halogen atom, alkyl group and alkoxy group. The heat-sensitive adhesive material according to any one of claims 2 to 12, wherein the heat-sensitive adhesive layer further contains a eutectic agent, and the eutectic agent is a dibenzyl ester oxalate compound represented by the following structural formula (6). .
However, in Structural Formula (6), Z represents one of a hydrogen atom, a halogen atom, and an alkyl group.   14. The heat-sensitive adhesive material according to claim 1, wherein the total thickness of the under layer and the heat-sensitive adhesive layer is 13 to 30 μm.   The heat-sensitive adhesive material according to any one of claims 1 to 14, comprising a recording layer and a protective layer in this order on the surface of the support that does not have the heat-sensitive adhesive layer.   The heat-sensitive recording layer according to claim 15, wherein the recording layer is any one of a heat-sensitive recording layer, a heat-melt transfer recording ink-receiving layer, an electrophotographic toner image-receiving layer, a silver halide photographic recording layer, and an ink-jet ink image-receiving layer. Adhesive material.   The heat-sensitive adhesive material according to claim 16, wherein the heat-sensitive recording layer contains a leuco dye and a developer.   The heat-sensitive adhesive material according to any one of claims 15 to 17, wherein the protective layer contains polyvinyl alcohol having a reactive carbonyl group and a hydrazide compound.   The heat-sensitive adhesive material according to claim 15, which has an ink image formed with a UV curable ink.   The heat-sensitive adhesive material according to any one of claims 15 to 19, wherein the recording layer surface is subjected to pre-printing having visual information, and the heat-sensitive adhesive layer surface is subjected to eye mark printing having a sensing function.   The heat-sensitive adhesive material according to any one of claims 1 to 20, wherein the support is any one of synthetic paper and a plastic film.   The heat-sensitive adhesive material according to any one of claims 1 to 21, which is any one of a label shape, a sheet shape, a label sheet shape, and a roll shape.