JPH08302302A - Plasticizer, thermoplastic resin composition, tacky adhesive and tacky adhesive substrate - Google Patents

Abstract

PURPOSE: To improve the antiblocking property and adhesive property of a heat-sensitive delayed tack thermoplastic resin composition by incorporating a thermoplastic resin, a tackifier, and a particular plasticizer. CONSTITUTION: 100 pts.wt. thermoplastic resin (A) having a glass transition temp. of -5 deg.C or above is mixed with 10 to 200 pts.wt. tackifier (B), 30 to 500 pts.wt. plasticizer (C) of a polyester compd. comprising an arom. substd. alkyl alcohol (a 2C or higher alkyl) with a polybasic acid, and, if necessary, titanium oxide, paraffin or the like, a dispersant, an antifoaming agent, and a thickener are added to the mixture to prepare a heat-sensitive delayed tack type thermoplastic resin compsn. as an adhesive. A substrate is coated with this adhesive, and the coating is dried to prepare a heat-sensitive, delayed tack, adhesive sheet.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat-sensitive delayed-tack type thermoplastic resin composition excellent in blocking resistance and adhesiveness using a specific plasticizer, a pressure-sensitive adhesive, and the pressure-sensitive adhesive coated on a substrate. The present invention relates to a heat-sensitive delayed tack-type pressure-sensitive adhesive base material obtained by working. This heat-sensitive delayed tack type adhesive substrate is, for example, a bottle of alcoholic beverage, a bottle of soft drink, a bottle of shampoo,
It is useful as a label for medicine bottles, motor oil cans, stationery boxes, etc.

[0002]

2. Description of the Related Art Conventional heat-sensitive delayed tack type adhesives which are non-adhesive at room temperature, but which appear to be sticky by heating, and which remain sticky for a long time even after leaving the heat source As described in "Adhesion Handbook", 12th Edition (published by Kobunshi Kogyokai, 1980), a thermoplastic resin, a tackifier, and a solid plasticizer are used as a basic skeleton. The thermoplastic resin forms the basis of the pressure-sensitive adhesive, and cohesive force at the time of use cannot be obtained without it. Further, the solid plasticizer does not give plasticity to the resin at room temperature, but it is melted by heating and swells or dissolves the resin to develop tackiness. And once melted, it solidifies slowly, so
After heating, stickiness is maintained for a certain period of time. The tackifier is a component for increasing the tackiness when activated by heating. The form of the coating liquid for producing the heat-sensitive delayed tack type pressure-sensitive adhesive sheet is a hot melt type (eg, JP-A-55-16055 and JP-A-56-1).
No. 06984), organic solvent type (eg; JP-A-51)
No. 111246 gazette) and an aqueous type (“polymer latex adhesive” by Soichi Muroi, published by Polymer Publishing Association) are known.

However, when the pressure-sensitive adhesive sheet is rolled up and stored, it is difficult to peel off due to the slight adhesiveness of the pressure-sensitive adhesive contact surface, and some printers generate heat during label printing. However, there is a problem that the blocking resistance is poor, which means that the property is poor.

As a method of improving the blocking resistance, a method of adding a wax to the pressure-sensitive adhesive component is disclosed in JP-B-62-218.
However, it is not sufficient. Also,
Japanese Patent Laid-Open No. 172784/1988 discloses a method in which the smoothness of the coated surface is set within a certain numerical range when the adhesive is coated on the substrate, but it is difficult to control the smoothness of the coated surface. Is.

[0005]

DISCLOSURE OF THE INVENTION The present invention is directed to a plasticizer which improves the blocking resistance and adhesiveness of the conventional thermosensitive delayed tack type adhesive thermoplastic resin composition, and a thermoplastic resin composition containing the same. A pressure-sensitive adhesive comprising the same, and a pressure-sensitive adhesive substrate using the same.

[0006]

Means for Solving the Problems The present inventors have earnestly studied a plasticizer to be added to a heat-sensitive delayed tack type tacky thermoplastic resin composition having good blocking resistance without deteriorating the adhesiveness. The present invention has been completed.

That is, the present invention is a plasticizer characterized by being a polyester compound comprising an aromatic group-substituted alkyl alcohol (where the alkyl group preferably has 2 or more carbon atoms) and a polybasic acid, preferably an aromatic compound. The group-substituted alkyl alcohol is phenyl or phenoxyethanol, (a) a thermoplastic resin, (b) a tackifier, and (c) an aromatic-group-substituted alkyl alcohol (however, preferably the alkyl group has 2 or more carbon atoms) And a plasticizer which is a polyester compound consisting of a polybasic acid, preferably a thermoplastic resin composition comprising a solid plasticizer, preferably the thermoplastic resin (a) is an emulsion type thermoplastic resin, The present invention provides a pressure-sensitive adhesive and a heat-sensitive delayed tack type pressure-sensitive adhesive base material obtained by coating the base material with the pressure-sensitive adhesive.

(Structure) The plasticizer (c) of the present invention is a polyester compound comprising an aromatic group-substituted alkyl alcohol (A) (where the alkyl group has 2 or more carbon atoms) and a polybasic acid (B). is there. A solid compound is preferable.

As the aromatic group-substituted alkyl alcohol (A), the carbon of the alkyl group is, for example, 2-phenylethanol, 1-phenylethanol, 2-phenoxyethanol, 3-phenyl-1-propanol, 2-hydroxyethylbenzyl ether, etc. Is mentioned. Polybasic acid
Examples of (B) include saturated aliphatic dibasic acids having 2 to 12 carbon atoms such as oxalic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and dodecanedicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid. Aromatic polybasic acids such as 2,6-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, trimellitic acid and pyromellitic acid, saturated alicyclic rings such as hexahydrophthalic acid and 1,4-cyclohexanedicarboxylic acid Formulas include dibasic acids and unsaturated dibasic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, mesaconic acid, β-hydromuconic acid, tetrahydrophthalic acid or their anhydrides.

The polyester compound which is a plasticizer composed of these alcohols and acids is preferably, for example, di-2.
-Phenylethyl isophthalate, di2-phenoxyethyl adipate, di2-phenoxyethyl 1,4-cyclohexanedicarboxylate and the like can be mentioned. Of these, esters having a melting point of 75 ° C to 140 ° C are preferable. If the melting point is lower than 75 ° C, the blocking resistance is inferior, and if it exceeds 140 ° C, it takes time to heat the pressure-sensitive adhesive, productivity is deteriorated, and the substrate may be deteriorated.

The plasticizer of the present invention provides a composition having a good balance between blocking resistance and adhesiveness to a thermoplastic resin. These plasticizers may be used alone or in combination of two or more. In addition, if necessary, other plasticizers may be used in combination within a range that does not impair the effects of the present invention.

The amount of the plasticizer used in the present invention is preferably 30 to 500 parts by weight, particularly 50 to 250 parts by weight, based on 100 parts by weight of the thermoplastic resin.

Other plasticizers include, for example, diphenyl phthalate, dihexyl phthalate, dicyclohexyl phthalate,
Dimethyl phthalate, sucrose benzoate, ethylene glycol dibenzoate, trimethylol ethane tribenzoate, glyceride tribenzoate, pentaerythrite tetrabenzoate, sucrose octaacetate, tricyclohexyl citrate, N-cyclohexyl-p-toluene sulfone Examples thereof include amides and the like, and solid ones thereof are preferable.

The thermoplastic resin (a) of the present invention is preferably an emulsion type resin such as vinyl acetate type, acrylic type, styrene type resin and rubber type resin.
Specifically, for example, polyvinyl acetate, polybutyl methacrylate, vinyl chloride-vinylidene chloride copolymer, ethylene-vinyl chloride, ethylene-acrylic acid ester copolymer, vinyl acetate-2-ethylhexyl acrylate, vinyl acetate-ethylene copolymer, Ethylene-vinyl acetate-acrylic acid ester copolymer, vinylpyrrolidone-styrene copolymer, vinylpyrrolidone-ethyl acrylate copolymer, polybutadiene, styrene-butadiene copolymer, styrene-butadiene block copolymer, styrene-isoprene block copolymer,
Styrene-butadiene-methacrylic acid copolymer, styrene-butadiene-acrylic acid copolymer, styrene-
Examples thereof include acrylic acid ester copolymer, urethane resin, chlorinated polypropylene, ethyl cellulose and the like.
Two or more of these thermoplastic resins may be used in combination. Further, in terms of blocking resistance, the glass transition temperature is -5 ° C.
The above is preferable.

Examples of the tackifier (b) of the present invention include terpene resins (homopolymers such as α-pinene, β-pinene and dipentene or copolymers thereof, terpenes,
Terpene / phenol copolymers, hydrogenated products thereof, etc., aliphatic petroleum resins, aromatic petroleum resins, coumarone-indene resins, styrene resins, phenol resins,
Terpene-phenolic resin, rosin derivative (rosin such as rosin abietic acid, polymerized rosin, hydrogenated rosin,
And esters thereof with glycerin, pentaerythritol, ethylene glycol, diethylene glycol and the like, maleic acid adducts, resin acid dimers and the like). The softening point of the tackifier is preferably 70 to 145 ° C. The amount of the tackifier used is preferably 10 to 200 parts by weight, and particularly 40 to 1 part by weight with respect to 100 parts by weight of the thermoplastic resin.
50 parts by weight is preferred. When it is less than 10 parts by weight, the viscosity and adhesive strength of the thermoplastic resin are low, and when it exceeds 200 parts by weight, the blocking resistance becomes poor.

In addition to these, as additives, titanium oxide,
Inorganic substances such as alumina, colloidal silica, kaolin, and talc, organic substances such as paraffin, natural wax, natural resin, and powdered styrene, and, if necessary, a dispersant and a defoaming agent,
Thickeners and the like can also be used. When a solid plasticizer is used, it may be coated with an inorganic compound such as titanium oxide, magnesium oxide or aluminum oxide.

The resin composition of the present invention is mainly used as a delayed tack type pressure-sensitive adhesive, but is also useful as a hot melt adhesive or the like.

Examples of the base material of the present invention include films, sheets, tape-shaped paper, plastic, wood, cloth and non-woven fabric.

As a means for applying the resin composition of the present invention to a substrate such as paper, it is desirable to apply the resin composition of the present invention as an aqueous dispersion (emulsion).
It may be dissolved in an organic solvent and applied, or the resin composition of the present invention may be directly heated and melted and applied. When preparing an aqueous dispersion, there are a method of premixing the composition and water dispersion, a method of dispersing a solid plasticizer in a thermoplastic resin emulsion and a tackifier emulsion, and a method of dispersing a solid plasticizer in an emulsion. There are a method of dispersing the molten solid plasticizer, a method of dispersing the solid plasticizer while making it into a fine powder, a method of dispersing the solid plasticizer made into a fine powder, and a method of mixing an aqueous dispersion of the solid plasticizer. . A gravure coater, a call coater, a bar coater or the like can be used for coating.

The adhesive substrate of the present invention is preferably a label for, for example, a bottle of alcoholic beverage, a bottle of soft drink, a bottle of shampoo, a bottle of medicine, a can of motor oil, a box of stationery, etc. Examples include adhesive tapes, patches, iron prints, etc.

Next, in order to further clarify the characteristics of the present invention, a specific description will be given with reference to examples. In addition, "part" in the sentence
All "%" indicate weight basis.

[0022]

【Example】

Example 1 200 parts of styrene / acrylic emulsion (solid content 50%) as a thermoplastic resin, 40 parts of rosin ester emulsion (solid content 50%) as a tackifier, and di2-phenylethyl terephthalate (TP) as a solid plasticizer.
A / PhEt: melting point 108 ° C.) (120 parts) and water (66 parts) were mixed to prepare a heat-sensitive delayed tack adhesive. This adhesive was coated on a high-quality paper so as to have a solid content of 15 g / m ² and then dried at 40 ° C. for 2 minutes to obtain a heat-sensitive delayed tack type adhesive sheet. This sheet was evaluated for blocking resistance and adhesiveness. This is shown in Table 1.

Example 2 Acrylic emulsion (solid content 5
The same procedure as in Example 1 was carried out except that 200 parts (0%) was used.

Example 3 Example 2 was repeated except that 100 parts of di2-phenoxyethyl isophthalate (IPA / PhOEt: melting point 77 ° C., solid) was used as a plasticizer.

Example 4 Example 2 was repeated except that 100 parts of di2-phenoxyethyl terephthalate (TPA / PhOEt: melting point 114 ° C., solid) was used as a plasticizer.

Example 5 As a plasticizer, di-2-phenoxyethyl adipate (AA
/ PhOEt: melting point 93 ° C., solid) 100 parts were used in the same manner as in Example 2.

Example 6 Di2-phenoxyethyl-1,4-cyclohexanedicarboxylate (CHDA / PhOEt: as a plasticizer)
Melting point 90 ° C., solid) The procedure of Example 2 was repeated except that 100 parts were used.

Example 7 Example 4 was repeated except that 200 parts of styrene / acrylic emulsion (solid content 50%) was used as the thermoplastic resin.

Example 6 Styrene-butadiene copolymer (SBR) emulsion (styrene / butadiene = 70) as a thermoplastic resin
/ 30%, solid content 50%) 200 parts, rosin ester emulsion as tackifier (solid content 50%) 60
Parts, 160 parts of di2-phenoxyethyl terephthalate (TPA / PhOEt: melting point 114 ° C.) as a solid plasticizer and 160 parts of water were mixed to prepare a heat-sensitive delayed tack adhesive. 15g of solid content on this adhesive
After coating so that / m ^2, dried for 2 minutes at 40 ° C., to obtain a heat-sensitive delayed tack sheet. This sheet was evaluated for blocking resistance and adhesiveness.

Comparative Example 1 Dicyclohexyl phthalate (DCHP:
Melting point 63 ° C., solid) The procedure of Example 1 was repeated except that 120 parts were used. This is shown in Table 2.

Comparative Example 2 Dicyclohexyl phthalate (DCHP: as a plasticizer)
Melting point 63 ° C., solid) The same procedure as in Example 2 was repeated except that 120 parts was used. This is shown in Table 2.

Comparative Example 3 Dicyclohexyl phthalate (DCHP:
Melting point 63 ° C., solid) The procedure of Example 8 was repeated except that 120 parts were used. This is shown in Table 2.

Comparative Example 4 The procedure of Example 2 was repeated except that 120 parts of pentaerythritol tetrabenzoate (Pent / Bz: melting point 96 ° C., solid) was used as a plasticizer. This is shown in Table 2.

[Evaluation Method] Blocking resistance: The pressure-sensitive adhesive sheet was heated at 60 ° C. or 65 ° C. for 1 hour, and the tackiness on the surface immediately after it was evaluated by touch with a finger. (○
If so, it was passed) ○: No tackiness △: Some tackiness ×: There is tackiness

Adhesion: The pressure-sensitive adhesive sheet is applied to the iron surface at 130 ° C.
It was heated for 10 seconds at 30 minutes, and after 30 seconds, it was attached to a copy paper or cardboard and the adhesiveness after 1 hour was evaluated by touch with a finger.
(Passed if ◯) ○: Adhesive strength is sufficient △: Adhesive strength is small ×: Adhesive strength is poor

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

The specific plasticizer of the present invention is added to the heat-sensitive delayed tack type thermoplastic resin composition,
The thermoplastic resin composition is excellent in blocking resistance without deteriorating the adhesiveness as a pressure-sensitive adhesive, and when this is used as a pressure-sensitive adhesive, a good heat-sensitive delayed tack type pressure-sensitive adhesive base material can be obtained. . The adhesive base material has a great industrial utility value as an adhesive for labels such as alcohol bottles, soft drink bottles, shampoo bottles, pharmaceutical bottles, motor oil cans, and stationery boxes.

Claims (8)

[Claims] 1. A plasticizer which is a polyester compound comprising an aromatic group-substituted alkyl alcohol (where the alkyl group has 2 or more carbon atoms) and a polybasic acid. 2. The plasticizer according to claim 1, wherein the multiester compound is solid. 3. (a) thermoplastic resin, (b) tackifier, (c)
A thermoplastic resin composition comprising the plasticizer according to claim 1. 4. The plasticizer according to claim 1, wherein the aromatic group-substituted alkyl alcohol is phenyl or phenoxyethanol. 5. The thermoplastic resin composition according to claim 3, wherein the thermoplastic resin (a) is an emulsion type thermoplastic resin. 6. A pressure-sensitive adhesive comprising the thermoplastic resin composition according to claim 3. 7. A heat-sensitive delayed-tack type pressure-sensitive adhesive substrate, which is obtained by applying the pressure-sensitive adhesive according to claim 6 to a substrate. 8. The pressure-sensitive adhesive substrate according to claim 7, which is a label.