JP6884674B2 - Adhesive composition - Google Patents

Description

The present invention relates to an adhesive composition containing an acrylic block copolymer suitable for an adhesive or the like.

It has been conventionally known to use an acrylic block copolymer or a composition containing an acrylic block copolymer as an adhesive.
For example, a methacrylic acid alkyl ester-based polymer having a glass transition temperature of 110 ° C. or higher and syndiotacticity of 70% or higher at both ends of a (meth) acrylic acid alkyl ester-based polymer block having a glass transition temperature of 30 ° C. or lower. A block copolymer composition containing a block-bonded triblock copolymer and a (meth) acrylic acid alkyl ester-based diblock copolymer, and a pressure-sensitive adhesive comprising the composition are known (Patent Document 1). reference). Further, a pressure-sensitive adhesive composition containing a specific diblock copolymer composed of a methacrylic acid alkyl ester-based polymer block and an acrylic acid alkyl ester-based polymer block and a (meth) acrylic acid ester-based triblock copolymer is known. (See Patent Document 2). Further, a pressure-sensitive adhesive composition containing a triblock copolymer composed of a specific methacrylic acid alkyl ester-based polymer block and an acrylic acid alkyl ester-based polymer block and a diblock copolymer is known (Patent Document 3). reference).

Japanese Unexamined Patent Publication No. 11-323072 Japanese Unexamined Patent Publication No. 2004-2736 Japanese Unexamined Patent Publication No. 2005-307063

The pressure-imparting resins and plasticizers specifically studied in the pressure-sensitive adhesives and pressure-sensitive adhesive compositions described in the above patent documents are limited, and are still improved in transparency, bleeding property, adhesive strength, tack, and the like. There is room. An object of the present invention is to provide an adhesive composition containing an acrylic block copolymer which is bleed-free and has excellent transparency, adhesive strength, and tackiness.

As a result of diligent studies to achieve the above object, the present inventors have made a viscous adhesive containing two specific acrylic triblock copolymers and a specific tackifier resin in a specific compounding ratio. It has been found that a viscous adhesive composition containing an acrylic block copolymer having no bleeding and excellent transparency, adhesive strength, tack, etc. can be obtained by using the composition.

According to the present invention, the above object is
[1] (i) It has two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and one polymer block (B) composed of acrylic acid ester units.
The acrylic ester unit constituting the polymer block (B) is an acrylic represented by the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ represents an organic group having 4 to 6 carbon atoms). It consists of an acid ester (1) unit and _{an acrylic ester (2) unit represented by the general formula CH 2} = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms).
It has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is a polymer block (A1) in the acrylic triblock copolymer (I). ) And (A2), an acrylic triblock copolymer (I) having a total content of 35% by mass or less.
(Ii) It has two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and one polymer block (D) composed of acrylic acid ester units.
The acrylic acid ester unit constituting the polymer block (D) is an acrylic represented by the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). It consists of an acid ester (3) unit (however, the polymer block (D) is different from the polymer block (B)).
It has a (C1)-(D)-(C2) block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and is a polymer block (C1) in an acrylic triblock copolymer (II). ) And (C2) include an acrylic triblock copolymer (II) having a total content of 35% by mass or less, and (iii') a tackifier resin having a softening point of less than 110 ° C.
An adhesive composition containing 1 to 300 parts by mass of a tackifier resin with respect to a total of 100 parts by mass of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II).
[2] (i) It has two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and one polymer block (B) composed of acrylic acid ester units.
The acrylic ester unit constituting the polymer block (B) is an acrylic represented by the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ represents an organic group having 4 to 6 carbon atoms). It consists of an acid ester (1) unit and _{an acrylic ester (2) unit represented by the general formula CH 2} = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms).
It has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is a polymer block (A1) in the acrylic triblock copolymer (I). ) And (A2), an acrylic triblock copolymer (I) having a total content of 35% by mass or less.
(Ii) It has two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and one polymer block (D) composed of acrylic acid ester units.
The acrylic acid ester unit constituting the polymer block (D) is an acrylic represented by the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). It consists of an acid ester (3) unit (however, the polymer block (D) is different from the polymer block (B)).
It has a (C1)-(D)-(C2) block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and is a polymer block (C1) in an acrylic triblock copolymer (II). ) And (C2), an acrylic triblock copolymer (II) having a total content of 35% by mass or less.
(Iii') Contains a tackifier resin having a softening point of less than 110 ° C., and (iv) a plasticizer.
Adhesive containing 1 to 300 parts by mass of the tackifier resin and 100 parts by mass or less of the plasticizer with respect to a total of 100 parts by mass of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). Adhesive composition,
[3] (i) It has two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and one polymer block (B) composed of acrylic acid ester units.
The acrylic ester unit constituting the polymer block (B) is an acrylic represented by the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ represents an organic group having 4 to 6 carbon atoms). It consists of an acid ester (1) unit and _{an acrylic ester (2) unit represented by the general formula CH 2} = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms).
It has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is a polymer block (A1) in the acrylic triblock copolymer (I). ) And (A2), an acrylic triblock copolymer (I) having a total content of 35% by mass or less.
(Ii) It has two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and one polymer block (D) composed of acrylic acid ester units.
The acrylic acid ester unit constituting the polymer block (D) is an acrylic represented by the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). It consists of an acid ester (3) unit (however, the polymer block (D) is different from the polymer block (B)).
It has a (C1)-(D)-(C2) block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and is a polymer block (C1) in an acrylic triblock copolymer (II). ) And (C2), an acrylic triblock copolymer (II) having a total content of 35% by mass or less.
(V) It has one polymer block (E) composed of methacrylic acid ester units and one polymer block (F) composed of acrylic acid ester units.
It has a block structure (E)-(F), has a weight average molecular weight (Mw) of 10,000 to 120,000, and contains the polymer block (E) in the acrylic diblock copolymer (III). Acrylic diblock copolymer (III) having a content of 25% by mass or less and
(Iii') Contains a tackifier resin having a softening point of less than 110 ° C.
Acrylic diblock copolymer (III) is added in an amount of 1 to 500 parts by mass, and a tackifier resin is added to a total of 100 parts by mass of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). Adhesive composition containing 1 to 300 parts by mass,
[4] (i) It has two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and one polymer block (B) composed of acrylic acid ester units.
The acrylic ester unit constituting the polymer block (B) is an acrylic represented by the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ represents an organic group having 4 to 6 carbon atoms). It consists of an acid ester (1) unit and _{an acrylic ester (2) unit represented by the general formula CH 2} = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms).
It has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is a polymer block (A1) in the acrylic triblock copolymer (I). ) And (A2), an acrylic triblock copolymer (I) having a total content of 35% by mass or less.
(Ii) It has two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and one polymer block (D) composed of acrylic acid ester units.
The acrylic acid ester unit constituting the polymer block (D) is an acrylic represented by the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). It consists of an acid ester (3) unit (however, the polymer block (D) is different from the polymer block (B)).
It has a (C1)-(D)-(C2) block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and is a polymer block (C1) in an acrylic triblock copolymer (II). ) And (C2), an acrylic triblock copolymer (II) having a total content of 35% by mass or less.
(V) It has one polymer block (E) composed of methacrylic acid ester units and one polymer block (F) composed of acrylic acid ester units.
It has a block structure (E)-(F), has a weight average molecular weight (Mw) of 10,000 to 120,000, and contains the polymer block (E) in the acrylic diblock copolymer (III). Acrylic diblock copolymer (III) in which is 25% by mass or less,
(Iii') Contains a tackifier resin having a softening point of less than 110 ° C., and (iv) a plasticizer.
Acrylic diblock copolymer (III) is added in an amount of 1 to 500 parts by mass, and a tackifier resin is added to a total of 100 parts by mass of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). Adhesive composition containing 1 to 300 parts by mass and 100 parts by mass or less of a plasticizer;
Is achieved by providing.

According to the present invention, it is possible to obtain a viscous adhesive composition containing an acrylic block copolymer having no bleeding and having excellent transparency, adhesive strength, tack and the like.

Hereinafter, the present invention will be described in detail. In the present specification, "(meth) acrylic acid ester" is a general term for "methacrylic acid ester" and "acrylic acid ester", and "(meth) acrylic" is a general term for "methacrylic acid" and "acrylic". It is a generic term.

(Acrylic triblock copolymer (I))
The acrylic triblock copolymer (I) contained in the adhesive composition of the present invention is composed of two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and an acrylic acid ester unit. The acrylic ester unit having one polymer block (B) and constituting the polymer block (B) is the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ has 4 carbon atoms. Acrylic acid ester (1) unit represented by (representing an organic group of ~ 6) and the general formula CH ₂ = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms). It consists of the acrylic acid ester (2) units shown, has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is an acrylic triblock. The total content of the polymer blocks (A1) and (A2) in the copolymer (I) is 35% by mass or less.

(Polymer blocks (A1) and (A2))
The acrylic triblock copolymer (I) has a polymer block composed of two methacrylic acid ester units (A1) and (A2).

Examples of the methacrylic acid ester that is a constituent unit of the polymer blocks (A1) and (A2) include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, and methacrylic acid. Isobutyl, sec-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, methacrylic acid Methacrylic acid esters without functional groups such as isobornyl, phenyl methacrylate, benzyl methacrylate; methoxyethyl methacrylate, ethoxyethyl methacrylate, diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate, 2-aminoethyl methacrylate, Examples thereof include methacrylic acid esters having functional groups such as glycidyl methacrylate and tetrahydrofurfuryl methacrylate.

Among these, methacrylic acid ester having no functional group is preferable from the viewpoint of improving the heat resistance and durability of the obtained polymer, and methyl methacrylate, ethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, etc. Isobornyl methacrylate and phenyl methacrylate are more preferable, and methyl methacrylate is further preferable because the phase separation between the polymer blocks (A1) and (A2) and the polymer block (B) becomes clearer and the cohesive force becomes higher. .. The polymer blocks (A1) and (A2) may be composed of one type of these methacrylic acid esters alone, or may be composed of two or more types. Further, the acrylic triblock copolymer (I) has two polymer blocks (A1) and (A2) as polymer blocks composed of methacrylic acid ester units, and these polymer blocks (A1) and The methacrylic acid esters constituting (A2) may be the same or different. The proportion of the methacrylic acid ester unit contained in the polymer blocks (A1) and (A2) is preferably 60% by mass or more in each of the polymer blocks (A1) and (A2), and is 80%. By mass% or more is more preferable, 90% by mass or more is further preferable, and 95% by mass or more is further preferable. Further, the ratio of the methacrylic acid ester units of the polymer blocks (A1) and (A2) may be 100% by mass.

The stereoregularity of the methacrylic acid ester units contained in the polymer blocks (A1) and (A2) composed of the methacrylic acid ester units may be the same or different from each other.

In the acrylic triblock copolymer (I), the total content of the polymer blocks (A1) and (A2) is 35% by mass or less, preferably 30% by mass or less, and preferably 25% by mass or less. More preferably, it is more preferably 20% by mass or less. The total content of the polymer blocks (A1) and (A2) is preferably 4% by mass or more, and more preferably 8% by mass or more. When the total content of the polymer blocks (A1) and (A2) is within the above range, excellent cohesive force is obtained when the acrylic triblock copolymer (I) is used in the adhesive composition. It develops and improves tack and adhesive strength. Further, the adhesive composition tends to have more excellent heat-resistant adhesiveness and holding power. Further, the contents of the polymer blocks (A1) and (A2) contained in the acrylic triblock copolymer (I) may be the same or different.

The glass transition temperature (Tg) of each of the polymer blocks (A1) and (A2) is preferably 60 to 140 ° C, more preferably 70 to 130 ° C, and further preferably 80 to 130 ° C. preferable. When the glass transition temperature is in this range, the polymer blocks (A1) and (A2) act as physical pseudo-crosslink points at the normal operating temperature of the adhesive, and cohesive force is exhibited. When used in an adhesive composition, it has excellent adhesive strength, durability, heat resistance, and the like. The glass transition temperature in the present specification is the extrapolation start temperature of the curve obtained by DSC measurement.

The Tg of each of the polymer blocks (A1) and (A2) may be the same or different. Even when the Tg of each of the polymer blocks (A1) and (A2) is different, it is preferable that the Tg of both polymer blocks is in the above range.

(Polymer block (B))
The acrylic triblock copolymer (I) has one polymer block (B) composed of an acrylic ester unit, and the acrylic ester unit is the general formula CH ₂ = CH-COOR ¹ (1) (1). In the formula, R ¹ represents an organic group having 4 to 6 carbon atoms), and the acrylic ester (1) unit and the general formula CH ₂ = CH-COOR ² (2) (in the formula, R ² has 7 carbon atoms). It consists of acrylic ester (2) units represented by (representing ~ 12 organic groups).

Examples of the acrylic acid ester (1) include n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, and cyclohexyl acrylate. , Acrylic acid ester having no functional group such as phenyl acrylate; Acrylic acid ester having a functional group such as ethoxyethyl acrylate, diethylaminoethyl acrylate, tetrahydrofurfuryl acrylate and the like can be mentioned.

Among these, acrylic acid esters having no functional groups are preferable from the viewpoint of improving the transparency, flexibility, and heat resistance of the obtained adhesive composition, and n-butyl acrylate and n- acrylate. Hexyl is more preferred, and n-butyl acrylate is even more preferred. These acrylic acid esters (1) may be used alone or in combination of two or more.

Examples of the acrylic acid ester (2) include 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, lauryl acrylate, benzyl acrylate, and phenoxyethyl acrylate. Be done.

Among these, 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, lauryl acrylate, from the viewpoint of improving the transparency, flexibility, cold resistance, and low temperature characteristics of the obtained adhesive composition. Acrylic acid esters such as phenoxyethyl acrylate are preferred. In addition, 2-ethylhexyl acrylate is excellent in adhesive strength and tack at low temperature (10-40 ° C.) of the obtained adhesive composition, and exhibits stable adhesive strength under a wide peeling speed condition. , N-octyl acrylate and iso-octyl acrylate are more preferable. Further, in the case of 2-ethylhexyl acrylate, the phase separation between the polymer blocks (A1) and (A2) and the polymer block (B) becomes clearer, so that the adhesive composition is particularly effective. It is particularly preferable in that it exhibits high cohesive force. These acrylic acid esters (2) may be used alone or in combination of two or more.

The mass ratio (1) / (2) of the acrylic acid ester (1) and the acrylic acid ester (2) in the polymer block (B) is preferably 5/95 to 95/5. When the mass ratio is within the above range, both the adhesive force to the high-polarity adherend and the adhesive force to the low-polarity adherend are compatible, and the tack is also excellent. Further, the mass ratio (1) / (2) of the acrylic acid ester is more preferably 25/75 to 75/25, and further preferably 40/60 to 60/40. The mass ratio of the acrylic acid ester (1) and the acrylic acid ester (2) is determined by the method described in Examples described later.

Examples of the combination of acrylic acid ester used in the polymer block (B) include n-butyl acrylate / 2-ethylhexyl acrylate, n-butyl acrylate / octyl acrylate, and the like (1) / (2). N-Hexyl acrylate / 2-ethylhexyl acrylate, n-butyl acrylate / lauryl acrylate, n-butyl acrylate / benzyl acrylate, n-butyl acrylate / [2-ethylhexyl acrylate / lauryl acrylate], etc. Can be mentioned. At this time, as the acrylic acid ester (1) and the acrylic acid ester (2) used, the difference in solubility parameter between the acrylic acid ester (1) and the acrylic acid ester (2) is 1.0 to 2.5 (MPa) ^1. It is more preferable that it is ^{/ 2.} The solubility parameters referred to in the present invention are "POLYMER HANDBOOK Force Edition", VII, pp. 675 to 714 (Wiley Interscience, 1999) and "Polymer Engineering and Science", 1974, pp. 14, 47. It can be calculated by the method described on page 154.

The polymer block (B) may be composed of a random copolymer of an acrylic acid ester (1) and an acrylic acid ester (2) constituting the polymer block (B), or may be composed of a block copolymer. It may be made of a tapered block copolymer, or may be made of a tapered block copolymer, but one made of a random copolymer is particularly preferable.

The total ratio of the acrylic acid ester (1) unit and the acrylic acid ester (2) unit contained in the polymer block (B) is preferably 60% by mass or more, more preferably 80% by mass or more, and 90% by mass or more. More preferably, 95% by mass or more is even more preferable. Further, the total ratio of the acrylic acid ester (1) unit and the acrylic acid ester (2) unit of the polymer block (B) may be 100% by mass.

In the acrylic triblock copolymer (I), the content of the polymer block (B) is usually 65% by mass or more, preferably 70% by mass or more, and more preferably 75% by mass or more. It is preferably 80% by mass or more, and more preferably 80% by mass or more. The content of the polymer block (B) is preferably 96% by mass or less, and more preferably 92% by mass or less. When the content of the polymer block (B) is within the above range, when the acrylic triblock copolymer (I) is used in the adhesive composition, excellent cohesive force is exhibited, and the tackiness is increased. Adhesive strength is further improved.

The glass transition temperature (Tg) of the polymer block (B) is preferably −100 to 30 ° C., more preferably −80 to 10 ° C., and even more preferably −70 to 0 ° C. When the glass transition temperature is in this range, it can have excellent tack and adhesive strength when used in an adhesive composition.

The polymer blocks (A1) and (A2) and the polymer block (B) may contain each other's monomer components as long as the effects of the present invention are not impaired. For example, it may have a tapered structure at the boundary between the polymer block (A1) or (A2) and the polymer block (B). Further, the polymer block (A1) or (A2) and the polymer block (B) may not contain each other's monomer components.

Further, the polymer blocks (A1) and (A2) and the polymer block (B) may contain other monomers, if necessary. Examples of such other monomers include vinyl-based monomers having a carboxyl group such as (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, and fumaric acid; (meth) acrylamide, (meth) acrylonitrile, and the like. Vinyl-based monomers having functional groups such as vinyl acetate, vinyl chloride, vinylidene chloride; aromatic vinyl-based monomers such as styrene, α-methylstyrene, p-methylstyrene, m-methylstyrene; butadiene, isoprene, etc. Conjugate diene-based monomers; olefin-based monomers such as ethylene, propylene, isobutene, and octene; lactone-based monomers such as ε-caprolactone and valerolactone. When each polymer block contains these other monomers, the content thereof is preferably 20% by mass or less, more preferably 10% by mass, based on the total mass of the monomers constituting each polymer block. % Or less, more preferably 5% by mass or less.

The acrylic triblock copolymer (I) has a (A1)-(B)-(A2) block structure in which the polymer block (A1), the polymer block (B), and the polymer block (A2) are bonded in this order. Has. When the acrylic triblock copolymer (I) has this structure, an adhesive composition having excellent adhesive strength, holding power, and cohesive strength can be obtained.

The weight average molecular weight (Mw) of the acrylic triblock copolymer (I) is 40,000 to 200,000. From the viewpoint of cohesive force and handleability at the time of manufacture, it is preferably 50,000 to 180,000, more preferably 55,000 to 160,000, and more preferably 60,000 to 140,000. Is even more preferable. If the Mw of the acrylic triblock copolymer (I) is less than 40,000, the cohesive force may be inferior. Further, if Mw exceeds 200,000, the handleability at the time of manufacturing may be inferior.

The molecular weight distribution (Mw / Mn) of the acrylic triblock copolymer (I) is preferably 1.0 to 1.5, and more preferably 1.0 to 1.4. The weight average molecular weight (Mw) and the number average molecular weight (Mn) in the present specification are the standard polystyrene-equivalent weight average molecular weight and the number average molecular weight obtained by gel permeation chromatography (GPC) measurement.

(Acrylic triblock copolymer (II))
The acrylic triblock copolymer (II) contained in the adhesive composition of the present invention is composed of two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and an acrylic acid ester unit1. The acrylic ester unit having one polymer block (D) and constituting the polymer block (D) is the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ has 4 carbon atoms. Consists of acrylic acid ester (3) units represented by (representing organic groups of ~ 12) (however, the polymer block (D) is different from the polymer block (B)), (C1)-(D)-. (C2) It has a block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and contains the total amount of the polymer blocks (C1) and (C2) in the acrylic triblock copolymer (II). The amount is 35% by mass or less.

(Polymer blocks (C1) and (C2))
The acrylic triblock copolymer (II) has a polymer block composed of two methacrylic acid ester units (C1) and (C2).

Specific examples of the methacrylic acid ester that is the constituent unit of the polymer blocks (C1) and (C2) are the constituent units of the polymer blocks (A1) and (A2) of the acrylic triblock copolymer (I). Similar to methacrylic acid ester.

Among these, methacrylic acid ester having no functional group is preferable from the viewpoint of improving the heat resistance and durability of the obtained polymer, and methyl methacrylate, ethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, etc. Isobornyl methacrylate and phenyl methacrylate are more preferable, and methyl methacrylate is further preferable because the phase separation between the polymer blocks (C1) and (C2) and the polymer block (D) becomes clearer and the cohesive force becomes higher. .. The polymer blocks (C1) and (C2) may be composed of one type of these methacrylic acid esters alone, or may be composed of two or more types. Further, the acrylic triblock copolymer (II) has two polymer blocks (C1) and (C2) as polymer blocks composed of methacrylic acid ester units, and these polymer blocks (C1) and The methacrylic acid esters constituting (C2) may be the same or different. The proportion of the methacrylic acid ester unit contained in the polymer blocks (C1) and (C2) is preferably 60% by mass or more in each of the polymer blocks (C1) and (C2), and is 80%. By mass% or more is more preferable, 90% by mass or more is further preferable, and 95% by mass or more is further preferable. Further, the ratio of the methacrylic acid ester units of the polymer blocks (C1) and (C2) may be 100% by mass.

In particular, when the polymer blocks (A1), (A2), (C1) and (C2) are all composed of the same methacrylic acid ester unit, the compatibility of the obtained adhesive composition is enhanced, which is preferable. Further, when the polymer blocks (A1), (A2), (C1) and (C2) are all composed of methyl methacrylate units, it is more preferable in that the cohesive force of the obtained adhesive composition is increased.

The stereoregularity of the methacrylic acid ester units contained in the polymer blocks (C1) and (C2) composed of the methacrylic acid ester units may be the same or different from each other.

In the acrylic triblock copolymer (II), the total content of the polymer blocks (C1) and (C2) is 35% by mass or less, preferably 30% by mass or less, and preferably 25% by mass or less. More preferably, it is more preferably 20% by mass or less. The total content of the polymer blocks (C1) and (C2) is preferably 4% by mass or more, and more preferably 8% by mass or more. When the total content of the polymer blocks (C1) and (C2) is within the above range, excellent cohesive force is obtained when the acrylic triblock copolymer (II) is used in the adhesive composition. It develops and improves tack and adhesive strength. Further, the adhesive composition tends to have more excellent heat-resistant adhesiveness and holding power. Further, the contents of the polymer blocks (C1) and (C2) contained in the acrylic triblock copolymer (II) may be the same or different.

The glass transition temperature (Tg) of each of the polymer blocks (C1) and (C2) is preferably 60 to 140 ° C, more preferably 70 to 130 ° C, and further preferably 80 to 130 ° C. preferable. When the glass transition temperature is in this range, the polymer blocks (C1) and (C2) act as physical pseudo-crosslink points at the normal operating temperature of the adhesive, and cohesive force is exhibited. When used in an adhesive composition, it has excellent adhesive strength, durability, heat resistance, and the like. The glass transition temperature in the present specification is the extrapolation start temperature of the curve obtained by DSC measurement.

The Tg of each of the polymer blocks (C1) and (C2) may be the same or different. Even when the Tg of each of the polymer blocks (C1) and (C2) is different, it is preferable that the Tg of both polymer blocks is in the above range.

(Polymer block (D))
The acrylic triblock copolymer (II) is _{an acrylic acid ester (3) represented by the general formula CH 2} = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). ) It has one polymer block (D) composed of units. However, this polymer block (D) is a polymer block different from the polymer block (B) contained in the acrylic triblock copolymer (I). Here, the fact that the polymer block (D) is different from the polymer block (B) means that at least one of the types and combinations of acrylic acid esters constituting these polymer blocks is different.

Examples of the acrylic acid ester (3) include n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, and 2 acrylic acid. -Acrylic acid ester without functional groups such as ethylhexyl, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, lauryl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate; acrylic Examples thereof include acrylic acid esters having a functional group such as ethoxyethyl acid acid, tetrahydrofurfuryl acrylate, diethylaminoethyl acrylate, and phenoxyethyl acrylate.

Above all, from the viewpoint of transparency and flexibility when prepared as an adhesive composition, it is represented by the general formula CH ₂ = CH-COOR ^3a (in the formula, R ^3a represents an organic group having 4 to 10 carbon atoms). Acrylic acid ester is more preferable, and from the viewpoint of improving the heat resistance, durability, and cold resistance of the obtained adhesive composition, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, and tert acrylate. -Butyl, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, cyclohexyl acrylate, phenyl acrylate, acrylic Acrylic acid esters without functional groups, such as benzyl acid acid, are more preferred. Furthermore, n-butyl acrylate, acrylic is a viscous adhesive composition because it has an appropriate adhesive strength and tack at room temperature and exhibits stable adhesive strength under a wide temperature range and a wide peeling speed condition. At least one selected from 2-ethylhexyl acid acid, n-octyl acrylate and isooctyl acrylate is more preferable, and n-butyl acrylate is particularly preferable.

The polymer block (D) may be composed of one of these acrylic acid esters (3) alone, or may be composed of two or more. From the viewpoint of the productivity of the acrylic triblock copolymer (II), it is preferable that the polymer block (D) is composed of one type of acrylic acid ester (3) alone. is there. The ratio of the acrylic acid ester (3) unit contained in the polymer block (D) is preferably 60% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, and more preferably 95% by mass or more. More preferred. Further, the ratio of the acrylic acid ester (3) unit of the polymer block (D) may be 100% by mass.

In the acrylic triblock copolymer (II), the content of the polymer block (D) is usually 65% by mass or more, preferably 70% by mass or more, and more preferably 75% by mass or more. It is preferably 80% by mass or more, and more preferably 80% by mass or more. The content of the polymer block (D) is preferably 96% by mass or less, and more preferably 92% by mass or less. When the content of the polymer block (D) is within the above range, when the acrylic triblock copolymer (II) is used in the adhesive composition, excellent cohesive force is exhibited, and the tackiness is increased. Adhesive strength is further improved.

The glass transition temperature (Tg) of the polymer block (D) is preferably −100 to 30 ° C., more preferably −80 to 10 ° C., and even more preferably −70 to 0 ° C. When the glass transition temperature is in this range, it can have excellent tack and adhesive strength when used in an adhesive composition.

The polymer blocks (C1) and (C2) and the polymer block (D) may contain each other's monomer components as long as the effects of the present invention are not impaired. For example, it may have a tapered structure at the boundary between the polymer blocks (C1) and (C2) and the polymer block (D). Further, the polymer blocks (C1) and (C2) and the polymer block (D) may not contain each other's monomer components.

Further, the polymer blocks (C1) and (C2) and the polymer block (D) may contain other monomers, if necessary. Specific examples of such other monomers are contained in the polymer block polymer blocks (A1) and (A2) and the polymer block (B) of the acrylic triblock copolymer (I), if necessary. Similar to other monomers exemplified as used for other monomeric units. When each polymer block contains these other monomers, the content thereof is preferably 20% by mass or less, more preferably 10% by mass, based on the total mass of the monomers constituting each polymer block. % Or less, more preferably 5% by mass or less.

The acrylic triblock copolymer (II) has a (C1)-(D)-(C2) block structure in which the polymer block (C1), the polymer block (D), and the polymer block (C2) are bonded in this order. Has. When the acrylic triblock copolymer (II) has this structure, an adhesive composition having excellent adhesive strength, holding power, and cohesive strength can be obtained.

The weight average molecular weight (Mw) of the acrylic triblock copolymer (II) is 50,000 to 250,000. From the viewpoint of cohesive force and handleability at the time of manufacture, it is preferably 70,000 to 250,000, more preferably 100,000 to 250,000, and 130,000 to 250,000. Is even more preferable. If the Mw of the acrylic triblock copolymer (II) is less than 50,000, the cohesive force may be inferior. Further, if Mw exceeds 250,000, the handleability at the time of manufacturing may be inferior.
The molecular weight distribution (Mw / Mn) of the acrylic triblock copolymer (II) is preferably 1.0 to 1.5, and more preferably 1.0 to 1.4.

The adhesive composition of the present invention contains an acrylic triblock copolymer (I) and an acrylic triblock copolymer (II). The ratio of the acrylic triblock copolymer (I) to the total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II) is preferably 5 to 95% by mass. It is more preferably 25 to 75% by mass. When the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II) are contained in the adhesive composition in such an amount ratio, the adhesive force to the highly polar adherend is obtained. It has both good adhesion to low-polarity adherends and is also excellent in tackiness. In addition, it is preferable that the adhesive composition of the present invention does not contain the acrylic diblock copolymer (III) described later.

(Acrylic diblock copolymer (III))
The adhesive composition of the present invention may contain an acrylic diblock copolymer (III). When the acrylic adhesive composition of the present invention contains the acrylic diblock copolymer (III), it is excellent in the balance of thermal stability, processability, adhesive strength and tack. The acrylic diblock copolymer (III) has one polymer block (E) composed of methacrylic acid ester units and one polymer block (F) composed of acrylic acid ester units, and (E)-. (F) It has a block structure, has a weight average molecular weight (Mw) of 10,000 to 120,000, and has a polymer block (E) content of 25% by mass in the acrylic diblock copolymer (III). It is as follows.

(Polymer block (E))
The acrylic diblock copolymer (III) has one polymer block (E) composed of methacrylic acid ester units.

Specific examples of the methacrylic acid ester that is the constituent unit of the polymer block (E) include the methacrylic acid ester that is the constituent unit of the polymer blocks (A1) and (A2) of the acrylic triblock copolymer (I). The same is true.

Among these, methacrylic acid ester having no functional group is preferable from the viewpoint of improving the heat resistance and durability of the obtained polymer, and methyl methacrylate, ethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, etc. Isobornyl methacrylate and phenyl methacrylate are more preferable, and methyl methacrylate is further preferable from the viewpoint that the phase separation between the polymer block (E) and the polymer block (F) becomes clearer and the cohesive force becomes higher. The polymer block (E) may be composed of one type of these methacrylic acid esters alone, or may be composed of two or more types. The proportion of the methacrylic acid ester unit contained in the polymer block (E) is preferably 60% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, still more preferably 95% by mass or more. Moreover, the ratio of the methacrylic acid ester unit of the polymer block (E) may be 100% by mass.

In the acrylic diblock copolymer (III), the content of the polymer block (E) is 25% by mass or less, preferably 20% by mass or less, and more preferably 10% by mass or less. The content of the polymer block (E) is preferably 2% by mass or more, and preferably 4% by mass or more. When the content of the polymer block (E) is within the above range, when the acrylic diblock copolymer (III) is contained in the adhesive composition, the cohesive force is not impaired and the tack is not impaired. Workability tends to be improved.

The glass transition temperature (Tg) of the polymer block (E) is preferably 60 to 140 ° C., more preferably 70 to 130 ° C., and even more preferably 80 to 130 ° C. When the glass transition temperature is in this range, the polymer block (E) acts as a physical pseudo-crosslink point at the normal operating temperature of the adhesive, and cohesive force is exhibited. When contained in a composition, it has excellent adhesive strength, durability, heat resistance, and the like.

(Polymer block (F))
The acrylic diblock copolymer (III) has one polymer block (F) composed of acrylic acid ester units.

Examples of the acrylic acid ester serving as a constituent unit of the polymer block (F) include methyl acrylate, ethyl acrylate, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, and acrylate. sec-butyl, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, acrylic acid Acrylic acid esters without functional groups such as lauryl, octadecyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate; methoxyethyl acrylate, ethoxyethyl acrylate, 2-hydroxyethyl acrylate, 2 acrylate -Acrylic acid esters having a functional group such as aminoethyl, glycidyl acrylate, tetrahydrofurfuryl acrylate, diethylaminoethyl acrylate, and phenoxyethyl acrylate can be mentioned.

Above all, from the viewpoint of transparency and flexibility when prepared as an adhesive composition, it is represented by the general formula CH ₂ = CH-COOR ⁴ (in the formula, R ⁴ represents an organic group having 1 to 10 carbon atoms). Acrylic acid ester is more preferable, and the phase separation between the polymer block (E) and the polymer block (F) becomes clear, and the adhesive composition exhibits high cohesiveness. Therefore, methyl acrylate and ethyl acrylate , Isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2 acrylate Acrylic acid esters having no functional group such as −ethylhexyl, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, cyclohexyl acrylate, phenyl acrylate, and benzyl acrylate are more preferable. Further, methyl acrylate and n-acrylic acid are obtained from the viewpoint that the adhesive composition has an appropriate adhesive strength and tack at room temperature and exhibits stable adhesive strength under a wide temperature range and a wide peeling speed condition. At least one selected from −butyl, 2-ethylhexyl acrylate, n-octyl acrylate and isooctyl acrylate is more preferable, and n-butyl acrylate is particularly preferable.

The polymer block (F) may be composed of one type of these acrylic acid esters alone, or may be composed of two or more types. The proportion of the acrylic acid ester unit contained in the polymer block (F) is preferably 60% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, still more preferably 95% by mass or more. Moreover, the ratio of the acrylic acid ester unit of the polymer block (F) may be 100% by mass.

In the acrylic diblock copolymer (III), the content of the polymer block (F) is usually 75% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more. preferable. The content of the polymer block (F) is preferably 98% by mass or less, and more preferably 96% by mass or less. When the content of the polymer block (F) is within the above range, when the acrylic diblock copolymer (III) is contained in the adhesive composition, the cohesive force is not impaired and the tack is not impaired. Workability is further improved.

The glass transition temperature (Tg) of the polymer block (F) is preferably −100 to 30 ° C., more preferably −80 to 10 ° C., and even more preferably −70 to 0 ° C. When the glass transition temperature is in this range, it can have excellent tack and adhesive strength when used in an adhesive composition.

The polymer block (E) and the polymer block (F) may contain each other's monomer components as long as the effects of the present invention are not impaired. For example, it may have a tapered structure at the boundary between the polymer block (E) and the polymer block (F). Further, the polymer block (E) and the polymer block (F) may not contain each other's monomer components.

Further, the polymer block (E) and the polymer block (F) may contain other monomer units, if necessary. Specific examples of such other monomers are contained in the polymer block polymer blocks (A1) and (A2) and the polymer block (B) of the acrylic triblock copolymer (I), if necessary. Similar to other monomers exemplified as used for other monomeric units. When each polymer block contains these other monomers, the content thereof is preferably 20% by mass or less, more preferably 10% by mass, based on the total mass of the monomers constituting each polymer block. % Or less, more preferably 5% by mass or less.

The acrylic diblock copolymer (III) has a (E)-(F) block structure in which the polymer block (E) and the polymer block (F) are bonded in this order. When the acrylic diblock copolymer (III) having such a structure is contained in the adhesive composition, the tackiness and processability tend to be further improved.

The weight average molecular weight (Mw) of the acrylic diblock copolymer (III) is 10,000 to 120,000. From the viewpoint of cohesive force and handleability at the time of manufacture, it is preferably 20,000 to 110,000, more preferably 25,000 to 100,000, and 30,000 to 90,000. Is even more preferable. If the Mw of the acrylic diblock copolymer (III) is less than 10,000, the cohesive force may be inferior. Further, if Mw exceeds 120,000, the handleability at the time of manufacturing may be inferior.
The molecular weight distribution (Mw / Mn) of the acrylic diblock copolymer (III) is preferably 1.0 to 1.5, and more preferably 1.0 to 1.4.

In the adhesive composition of the present invention, the content of the acrylic diblock copolymer (III) is 100 in total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). It is preferably 1 to 500 parts by mass, more preferably 10 to 400 parts by mass, and further preferably 20 to 300 parts by mass with respect to parts by mass. When the content of the acrylic diblock copolymer is in the above range, an adhesive composition having an excellent balance of cohesive force, processability, adhesive force, and tack can be obtained.

The methods for producing the acrylic triblock copolymers (I) and (II) and the acrylic diblock copolymer (III) are particularly limited as long as a polymer satisfying the conditions of the present invention regarding the chemical structure can be obtained. A method according to a known method can be adopted without being carried out. Generally, as a method of obtaining a block copolymer having a narrow molecular weight distribution, a method of living-polymerizing a monomer as a constituent unit is adopted. Examples of such a living polymerization method include a method of living polymerization using an organic rare earth metal complex as a polymerization initiator (see JP-A-06-93060), and an alkali metal or alkaline soil using an organic alkali metal compound as a polymerization initiator. A method of living anion polymerization in the presence of a mineral acid such as a salt of a similar metal (see Japanese Patent Application Laid-Open No. 05-507737), living anion polymerization using an organic alkali metal compound as a polymerization initiator in the presence of an organic aluminum compound. (Refer to JP-A-11-335432), Atom Transfer Radical Polymerization Method (ATRP) (Macromolecular Chemistry and Physics, 2000, Vol. 201, p. 1108 to 1114) and the like.

Among the above production methods, the method of living anionic polymerization using an organoalkali metal compound as a polymerization initiator in the presence of an organoaluminum compound results in high transparency of the obtained block copolymer, a small amount of residual monomers, and an odor. It is preferable because it can suppress the generation of air bubbles after bonding when it is used as an adhesive composition. Furthermore, the molecular structure of the methacrylic acid ester polymer block becomes highly syndiotactic, which has the effect of increasing the heat resistance of the adhesive composition, and can be industrially polymerized in the living room under relatively mild temperature conditions. It is also preferable in that the environmental load (mainly the power required for the refrigerator for controlling the polymerization temperature) is small in the case of production.

Examples of the organoaluminum compound include the following general formula (4).
AlR ⁵ R ⁶ R ⁷ (4)
(In the formula (4), R ⁵ , R ⁶ and R ⁷ each have an alkyl group which may independently have a substituent, a cycloalkyl group which may have a substituent, and a substituent. Table represents an aryl group which may have a substituent, an aralkyl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, or an N, N-disubstituted amino group. Or, R ⁵ is any of the above groups, and R ⁶ and R ⁷ together form an allylene oxy group which may have a substituent.) Examples include aluminum compounds.

The organoaluminum compound represented by the general formula (4) is isobutylbis (2,6-di-tert-butyl-4-methylphenoxy) from the viewpoints of high living property of polymerization and ease of handling. Aluminum, isobutylbis (2,6-di-tert-butylphenoxy) aluminum, isobutyl [2,2'-methylenebis (4-methyl-6-tert-butylphenoxy)] aluminum and the like are preferable.

Examples of the organic alkali metal compound include alkyllithium and alkyldilithium such as n-butyllithium, sec-butyllithium, isobutyllithium, tert-butyllithium, n-pentyllithium and tetramethylenedilithium; phenyllithium, p. -Aryllithium and aryldilithium such as trilllithium and lithium naphthalene; aralkyllithium and aralkyldilithium such as dilithium produced by the reaction of benzyllithium, diphenylmethyllithium, diisopropenylbenzene and butyllithium; lithium such as lithiumdimethylamide Amid; Examples thereof include lithium alkoxides such as methoxylithium and ethoxylithium. These may be used alone or in combination of two or more. Of these, alkyllithium is preferable because of its high polymerization initiation efficiency, and tert-butyllithium and sec-butyllithium are more preferable, and sec-butyllithium is even more preferable.

The living anionic polymerization is usually carried out in the presence of a solvent that is inert to the polymerization reaction. Examples of the solvent include aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as chloroform, methylene chloride and carbon tetrachloride; ethers such as tetrahydrofuran and diethyl ether, and toluene is preferably used. Be done.

The block copolymer is, for example, a step of forming a desired polymer block (polymer block (A1), polymer block (B), etc.) at a desired living polymer terminal obtained by polymerizing a monomer. It can be produced by stopping the polymerization reaction after repeating the process a desired number of times. Specifically, for example, in the presence of an organic aluminum compound, the first step and the second polymer block for polymerizing the monomer forming the first polymer block with a polymerization initiator composed of an organic alkali metal compound are used. The weight obtained through a multi-step polymerization step including a second step of polymerizing the polymer to be formed and, if necessary, a third step of polymerizing the monomer forming the third polymer block. Acrylic triblock copolymers (I) and (II) and acrylic diblock copolymer (III) can be produced by reacting the active end of the coalescence with alcohol or the like to terminate the polymerization reaction. According to the method as described above, the polymer block (A1) -polymer block (B) -polymer block (A2) or the polymer block (C1) -polymer block (D) -polymer block (C2). ), And a diblock copolymer composed of the polymer block (E) -polymer block (F).

The polymerization temperature was 0 to 100 ° C. when forming the polymer blocks (A1), (A2), (C1), (C2), and (E), and the polymer blocks (B), (D), and When forming (F), -50 to 50 ° C. is preferable. When the polymerization temperature is lower than the above range, the progress of the reaction is slowed down, and it takes a long time to complete the reaction. On the other hand, when the polymerization temperature is higher than the above range, the deactivation of the living polymer terminal increases, the molecular weight distribution becomes wide, and a desired block copolymer cannot be obtained. In addition, each polymer block can be polymerized in the range of 1 second to 20 hours.

(Adhesive-imparting resin)
The adhesive composition of the present invention contains a tackifier resin having a softening point of less than 110 ° C. When the adhesive composition of the present invention contains a tackifier resin having a softening point of less than 110 ° C., the adhesive strength, tackiness and compatibility are improved. The softening point is a value measured according to the ring ball method of JIS K2207. In addition, it is a preferable aspect that the adhesive composition of the present invention does not contain a plasticizer described later.

As the tackifier resin that can be blended in the pressure-sensitive adhesive composition of the present invention, any of the pressure-sensitive adhesive resins conventionally used in the pressure-sensitive adhesive can be used as long as the softening point is less than 110 ° C. Although not particularly limited, for example, rosin-based resins (rosin, rosin derivatives, and hydrogenated rosin derivatives obtained by further hydrogenating (hereinafter, also referred to as hydrogenated) or the like), terpene-based resins, terpenephenol-based resins, ( Hydrogenated) Petroleum-based resin, styrene-based resin, xylene-based resin, hydrogenated aromatic copolymer, phenol-based resin, kumaron-indene-based resin, and the like can be mentioned.

In the present invention, the rosin-based resin is an amber-colored, amorphous natural resin obtained from pine, and its main component is a mixture of abietic acid and its isomers. Further, the rosin-based resin also includes those modified by esterification, polymerization, hydrogenation, etc. by utilizing the reactivity of this abietic acid or its isomer. For example, unmodified rosins (eg, tall rosins, gum rosins, and wood rosins), polymerized rosins, disproportionated rosins, hydrogenated rosins, maleic acid modified rosins, fumaric acid modified rosins, and esters thereof (eg, glycerin esters, penta (Erythritol ester, methyl ester, ethyl ester, butyl ester, ethylene glycol ester, etc.) and those modified by hydrogenation etc. are mentioned, and hydrogenated rosin ester is particularly preferably used from the viewpoint of heat resistance and color resistance. Be done.

In the present invention, the terpene-based resin is an oligomer obtained by polymerizing a raw material containing a terpene-based monomer. Further, the terpene-based resin also includes an oligomer obtained by modifying the oligomer obtained in this manner by hydrogenation or the like. Terpenes generally mean polymers of isoprene (C ₅ H ₈ ) and are classified into _{monoterpenes (C 10} H ₁₆ ), sesquiterpenes (C ₁₅ H ₂₄ ), diterpenes (C ₂₀ H _{32), etc.} To. The terpene-based monomer is a monomer having these as a basic skeleton, and is, for example, α-pinene, β-pinene, dipentene, limonene, myrcene, aloosimene, osimene, α-ferrandrain, α-terpinene, γ. -Terpinene, terpinene, 1,8-cineole, 1,4-cineole, α-terpineneol, β-terpineneol, γ-terpineneol, sabinene, paramentadiens, curenes and the like can be mentioned. Further, the raw material containing terpene monomer, terpene monomer and other copolymerizable monomers, for example coumarone based monomers such as benzofuran (C ₈ H ₆ O); styrene, alpha- Vinyl aromatic compounds such as methylstyrene, vinyltoluene, divinyltoluene, 2-phenyl-2-butene; phenol, cresol, xylenol, propylphenol, norylphenol, hydroquinone, resorcin, methoxyphenol, bromophenol, bisphenol A, bisphenol F Phenolic monomers and the like may be contained. Examples of the oligomer obtained by polymerizing a raw material containing another monomer copolymerizable with the terpene-based monomer include a terpene phenol-based resin and the like. Further, the terpene resin also includes a product obtained by modifying the oligomer thus obtained by hydrogenation or the like.

In the present invention, the (hydrogenated) petroleum-based resin is composed of a C ₅ fraction, a C ₉ fraction, _{a purified component of the C 5} fraction, a purified component of the C ₉ fraction, or a mixture of these fractions or purified components. It is an oligomer obtained by polymerizing a raw material. Further, the oligomer obtained in this manner modified by hydrogenation or the like is also included in the above (hydrogenated) petroleum-based resin. Note that the C ₅ fraction, typically, cyclopentadiene, dicyclopentadiene, isoprene, 1,3-pentadiene, 2-methyl-1-butene, 2-methyl-2-butene, 1-pentene, 2-pentene and Cyclopentene and the like are included, and the C ₉ distillate usually contains styrene, allylbenzene, α-methylstyrene, vinyltoluene, β-methylstyrene, indene and the like. In addition, the C ₉ fraction may contain a small amount of the C ₈ fraction and the C _{10 fraction.}

The (hydrogenated) petroleum resin, C ₅ fraction or C ₅ resins the purified components were the raw material, C ₉ fraction or C ₉ resins the purified components to the raw material, C ₅ fraction or purified components thereof the a C ₉ fraction or mixture with its purified components were the raw material is roughly classified into C ₅ -C ₉ copolymer resin. Among these, hydrogenated petroleum-based resins are preferably used from the viewpoint of heat resistance and color resistance.

In the present invention, the aromatic hydrocarbon-based resins such as styrene-based resin, xylene-based resin, hydrogenated aromatic copolymer, and phenol-based resin are, for example, styrene, α-methylstyrene, vinyltoluene, β-methylstyrene, and divinyltoluene. , 2-Phenyl-2-butene, methoxystyrene, t-butylstyrene, chlorostyrene, inden, methylinden, phenol, cresol, xylenol, propylphenol, norylphenol, hydroquinone, resorcin, methoxyphenol, bromophenol, bisphenol A, It is an oligomer obtained by polymerizing a raw material composed of bisphenol F or a mixture thereof. Further, the oligomer obtained in this manner modified by hydrogenation or the like is also included. In addition, Kumaron-inden resin and the like can also be mentioned. Among these, a styrene resin is preferably used from the viewpoint of compatibility, heat resistance, and color resistance.

The softening point of the tackifier resin contained in the adhesive composition of the present invention is less than 110 ° C. and less than 100 ° C. from the viewpoint of processability of the obtained adhesive adhesive composition. It is preferably 96 ° C. or lower, more preferably 96 ° C. or lower.

The tackifier resin may be contained alone or in combination of two or more. When two or more of these tackifier resins are contained, it is desirable because the adhesive strength and tack balance are excellent. The softening point of the tackifier resin is preferably 30 ° C. or higher and lower than 110 ° C. from the viewpoint of exhibiting high adhesive strength and processability.

The content of the tackifier resin is 1 to 300 parts by mass with respect to 100 parts by mass in total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). When the tackifier resin is a rosin resin, a terpenphenol resin, a styrene resin, a xylene resin, a hydrogenated aromatic copolymer, a phenol resin, a kumaron-inden resin, etc., the content of the tackifier resin is within the above range. If there is, the balance of adhesive force, tack and cohesive force of the adhesive composition is excellent. From the viewpoint of achieving both higher adhesive strength, tackiness and cohesive strength, the content of the tackifier resin is 100 parts by mass in total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). On the other hand, it is preferably 10 to 250 parts by mass, and more preferably 15 to 200 parts by mass.

On the other hand, when the tackifier resin is a terpene-based resin composed of only (hydrogenated) petroleum-based resin and terpene-based monomer, it is difficult to increase the content from the viewpoint of compatibility with acrylic block copolymers. There is a tendency. From the viewpoint of adhesive strength, tack and cohesive strength, and compatibility, the content of the tackifier resin is 100 parts by mass in total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). On the other hand, it is preferably 2 to 80 parts by mass, and more preferably 2 to 60 parts by mass.

(Plasticizer)
The adhesive composition of the present invention may contain a plasticizer. By containing a plasticizer in the adhesive composition of the present invention, an adhesive composition having an excellent balance of adhesive strength, tackiness and processability can be obtained, and more generally, an adhesive composition can be obtained. The cost of the whole thing can be reduced.

Examples of such plasticizers include phthalates such as dibutylphthalate, din-octylphthalate, bis (2-ethylhexyl) phthalate, bis (2-ethylhexyl) terephthalate, din-decylphthalate, and diisodecylphthalate; Adiponic acid esters such as bis (2-ethylhexyl) adipate, diisodecyl adipate, din-octyl adipate; sebacic acid esters such as bis (2-ethylhexyl) sebacate, din-butyl sebacate; bis (2-ethylhexyl) azelate, etc. Azelaic acid esters; citrate esters such as tributyl acetyl citrate; paraffins such as chlorinated paraffins; glycols such as polypropylene glycol; epoxidized vegetable oils such as epoxidized soybean oil and epoxidized linseed oil; trioctyl Phthalate esters such as phosphate and triphenyl phosphate; subphosphate esters such as triphenyl phosphite; esterified products of adipic acid and 1,3-butylene glycol, esterified products of benzoic acid and dipropylene glycol, etc. Kind: Low molecular weight polymers such as low molecular weight polybutene, low molecular weight polyisobutylene, low molecular weight polyisoprene; acrylic oligomers such as n-butyl polyacrylate and 2-ethylhexyl polyacrylate; Diana process oil PW series (Idemitsu Kosan Co., Ltd.) Paraffin oils such as SUNPURE LW70 and P series (manufactured by Nippon Sun Oil Co., Ltd.); naphthene oils such as SUNPURE N90 and NX90, SUNTHENE series (manufactured by Japan Sun Oil Co., Ltd.); JSO AROMA790 (Japan Sun Oil Co., Ltd.) Aroma oils such as (manufactured by company) and Vivatec500 (manufactured by H & R) can be mentioned, and these are used alone or in admixture of two or more.

The content of the plasticizer is preferably 100 parts by mass or less, preferably 80 parts by mass or less, based on 100 parts by mass of the total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). It is more preferable that the amount is 40 parts by mass or less. When the content of the plasticizer is in the above range, a viscous adhesive composition having no bleeding and excellent adhesive strength can be obtained. In order to obtain the effect of containing the plasticizer in the adhesive composition, the total amount of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II) is 100 parts by mass. On the other hand, it is usually desirable to contain 5 parts by mass or more.

The adhesive composition of the present invention contains other polymers; softeners, heat stabilizers, light stabilizers, antistatic agents, flame retardants, foaming agents, colorants, as long as the effects of the present invention are not impaired. Additives such as a dye, a refractive index adjuster, a filler, a curing agent, and an antistatic agent may be contained. These other polymers and additives may be contained alone or in combination of two or more.

Other polymers include, for example, acrylic resins such as polymethyl methacrylate and (meth) acrylic acid ester copolymers; polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polybutene-1, poly-4-methyl. Olefin-based resins such as Penten-1, polynorbornene; Ethylene-based ionomers; Polystyrene, styrene-maleic anhydride copolymers, high-impact polystyrene, AS resin, ABS resin, AES resin, AAS resin, ACS resin, MBS resin, etc. Polystyrene resin; styrene-methyl methacrylate copolymer; polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polylactic acid; polyamide such as nylon 6, nylon 66, polyamide elastomer; polycarbonate; polyvinyl chloride; polyvinylidene chloride; polyvinyl Alcohol; ethylene-vinyl alcohol copolymer; polyacetal; vinylidene fluoride; polyurethane; modified polyphenylene ether; polyphenylene sulfide; silicone rubber modified resin; acrylic rubber; silicone rubber; styrene-based thermoplastic elastomer such as SEPS, SEBS, SIS, etc. ; Examples include olefin-based rubbers such as IR, EPR, and EPDM. Among these, acrylic resin, ethylene-vinyl acetate copolymer, AS resin, polylactic acid, from the viewpoint of compatibility with the acrylic triblock copolymer (I) contained in the adhesive composition. Polyvinylidene fluoride and styrene-based thermoplastic elastomers are preferable, and (meth) acrylic acid ester copolymers are more preferable.

Examples of the filler include inorganic fibers such as glass fiber and carbon fiber, and organic fibers; inorganic fillers such as calcium carbonate, talc, titanium oxide, silica, clay, barium sulfate and magnesium carbonate; carbon black and the like. .. The inclusion of these fillers imparts durability, heat resistance and weather resistance to the resulting adhesive composition.

When the adhesive composition of the present invention contains a curing agent, it can be suitably used as a curing adhesive. Examples of the curing agent include photocuring agents such as UV curing agents, heat curing agents, and the like, and examples thereof include benzoins, benzoin ethers, benzophenones, anthraquinones, benzyls, acetophenones, and diacetyls. .. Specifically, benzoin, α-methylol benzoin, α-t-butyl benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin-n-propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, α-methylol benzoin methyl ether, α −methoxybenzoin methyl ether, benzoinphenyl ether, benzophenone, 9,10-anthraquinone, 2-ethyl-9,10-anthraquinone, benzyl, 2,2-dimethoxy-1,2-diphenylethane-1-one (2,2) −Dimethoxy-2-phenylacetophenone), diacetyl and the like. The curing agent may be contained alone or in combination of two or more.

From the viewpoint of enhancing the effect of the above-mentioned curing agent, for example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, itaconic acid, and acrylic acid ester. , Methacrylic acid ester, crotonic acid ester, maleic acid ester and other esters; acrylamide; methacrylic amide; N-methylol acrylamide, N-hydroxyethyl acrylamide, N, N- (dihydroxyethyl) acrylamide and other acrylamide derivatives; N-methylol methacrylic Methacrylic amide derivatives such as amide, N-hydroxyethyl methacrylic amide, N, N- (dihydroxyethyl) methacrylic amide; vinyl ester; vinyl ether; mono-N-vinyl derivative; monomer such as styrene derivative; Oligomers and the like contained as constituents may be further contained in the adhesive composition of the present invention. From the viewpoint of increasing durability, esters such as acrylic acid ester, methacrylic acid ester, crotonic acid ester, and maleic acid ester; vinyl ether; styrene derivative; and an oligomer containing the monomer as a constituent are preferable. Further, in addition to these monomers, a cross-linking agent composed of a bifunctional or higher functional monomer or oligomer may be further contained.

When the adhesive composition of the present invention contains an anti-adhesive agent, improvement in handleability can be expected. Examples of the anti-sticking agent include fatty acids such as stearic acid and palmitic acid; fatty acid metal salts such as calcium stearate, zinc stearate, magnesium stearate, potassium palmitate, and sodium palmitate; polyethylene wax, polypropylene wax, and montanic acid. Waxes such as waxes; low molecular weight polyolefins such as low molecular weight polyethylene and low molecular weight polypropylene; acrylic resin powders; polyorganosiloxanes such as dimethylpolysiloxane; octadecylamine, alkyl phosphate, fatty acid esters, ethylenebisstearylamide, etc. Examples thereof include amide-based resin powder, fluororesin powder such as ethylene tetrafluoride resin, molybdenum disulfide powder, silicone resin powder, silicone rubber powder, and silica.

The method for producing the adhesive composition of the present invention is not particularly limited, and for example, each component is usually mixed or kneaded using a known mixing or kneading device such as a kneader ruder, an extruder, a mixing roll, and a Banbury mixer. It can be manufactured by mixing at a temperature in the range of ~ 250 ° C. Further, it may be produced by dissolving each component in an organic solvent, mixing the components, and then distilling off the organic solvent. The obtained adhesive composition can be used by being melted by heating, or may be dissolved in a solvent and used as a solution type adhesive. Examples of the solvent include toluene, ethyl acetate, ethylbenzene, methylene chloride, chloroform, tetrahydrofuran, methyl ethyl ketone, dimethyl sulfoxide, toluene-ethanol mixed solvent and the like. Of these, toluene, ethylbenzene, ethyl acetate and methyl ethyl ketone are preferable.

When the adhesive composition of the present invention is used by heating and melting, it is preferable that the melt viscosity is low from the viewpoint of processability and handleability. On the other hand, from the viewpoint of achieving both the adhesive force and the high holding force (creep resistance) of the adhesive composition, it is preferable that the melt viscosity is high.

The adhesive composition of the present invention is adhesive in the form of an adhesive layer made of the adhesive composition, a laminate containing the adhesive layer (for example, a laminated film or a laminated sheet), or the like. Suitable for adhesive products.

In order to form the adhesive layer, when the adhesive composition of the present invention is used by heating and melting, for example, a hot melt coating method, a T-die method, an inflation method, a calendar molding method, a lamination method and the like are used. It can be used to form a sheet or film. When the melt viscosity of the adhesive composition of the present invention is high, for example, when the melt viscosity at 180 ° C. exceeds 20,000 mPa · s, the hot melt is heated from the T die in order to be heated and melted at a higher temperature. A hot melt coating method in which is applied onto the support in a non-contact manner is preferable from the viewpoint of controlling the thickness of the adhesive layer, homogeneity, and heat resistance required for the support. When the adhesive composition of the present invention is used by dissolving it in a solvent, for example, a heat-resistant material such as polyethylene terephthalate or a flat plate or roll such as a steel belt is used as a support, and a bar coater or a roll is placed on the support. A method of applying a solution in which a composition containing an acrylic triblock copolymer (I), a tackifier resin, etc. is dissolved in a solvent using a roll coater, a die coater, a comma coater, or the like, and removing the solvent by drying. A viscous adhesive layer can be formed using (solution casting method).

The method for removing the solvent by drying is not particularly limited, and a conventionally known method can be used, but it is preferable to perform drying in a plurality of steps. When drying is performed in multiple stages, the first stage is dried at a relatively low temperature in order to suppress foaming due to the rapid volatilization of the solvent, and the second and subsequent stages are sufficiently dried. A method of drying at a high temperature is more preferable in order to remove the solvent.

The concentration of the composition containing the acrylic triblock copolymers (I) and (II) in the above solution, the tackifier resin, and the like is determined in consideration of the solubility of the composition in the solvent, the viscosity of the obtained solution, and the like. Although appropriately determined, the preferred lower limit is 5% by mass and the preferred upper limit is 70% by mass.

The above-mentioned laminate is obtained by laminating various base materials such as paper, cellophane, plastic material, cloth, wood, and metal with the adhesive layer made of the adhesive composition of the present invention. A base material layer made of a transparent material is suitable because the adhesive composition of the present invention is excellent in transparency and weather resistance, and thus a transparent laminate can be obtained. Examples of the base material layer made of a transparent material include polyethylene terephthalate, triacetyl cellulose, polyvinyl alcohol, cycloolefin resin, styrene-methyl methacrylate copolymer, polypropylene, polyethylene, polyvinyl chloride, and ethylene-vinyl acetate copolymer. , Polypolymers of polymers such as polycarbonate, polymethyl methacrylate, polyethylene or polypropylene and copolymers of various monomers, mixtures of two or more of these polymers, and a substrate layer made of glass or the like. It is not limited to these.

The structure of the laminate includes, for example, a two-layer structure consisting of an adhesive layer made of the adhesive composition of the present invention and a base material layer, and two layers of the base material layer and the adhesive adhesive composition of the present invention. A three-layer structure consisting of an adhesive layer (base material layer / adhesive layer / base material layer), and two different adhesive layers composed of the base material layer and the adhesive composition of the present invention (a adhesive layer). A) and a four-layer structure of the adhesive layer (b) and the base material layer (base material layer / adhesive layer (a) / adhesive layer (b) / base material layer), base material layer and book A four-layer structure (base material layer / adhesive layer (a)) consisting of an adhesive layer (a) made of the adhesive composition of the present invention, an adhesive layer (c) made of another material, and a base material layer. ) / Adhesive layer (c) / Base material layer), 5 layers of 3 layers of base material layer and 2 layers of adhesive layer composed of the adhesive composition of the present invention (base material layer / adhesive) (Assembly layer / base material layer / adhesive layer / base material layer) and the like, but are not limited thereto.

The thickness ratio of the laminate is not particularly limited, but the base layer / adhesive layer = 1/1000 to 1000/1 from the viewpoint of the adhesive strength, tackiness, durability, and handleability of the obtained adhesive product. It is preferably in the range of 1/200 to 200/1, and more preferably in the range of 1/200 to 200/1.

When producing the above-mentioned laminate, the adhesive layer and the base material layer may be formed and then bonded together by a lamination method or the like, or the adhesive layer may be formed directly on the base material layer. Good. Further, the layer structure may be formed at once by co-extruding the adhesive layer and the base material layer to produce a laminate as, for example, a co-extruded film or a co-extruded sheet.

In the laminate of the present invention, in order to enhance the adhesion between the base material layer and the adhesive layer, the surface of the base material layer may be subjected to surface treatment such as corona discharge treatment or plasma discharge treatment in advance. Further, an anchor layer may be formed on at least one surface of the adhesive layer and the base material layer by using a resin or the like having adhesiveness.

Examples of the resin used for the anchor layer include ethylene-vinyl acetate copolymers, ionomers, block copolymers (for example, styrene-based triblock copolymers such as SIS and SBS, and diblock copolymers). Examples thereof include ethylene-acrylic acid copolymers and ethylene-methacrylic acid copolymers. The anchor layer may be one layer or two or more layers.

When forming the anchor layer, the method is not particularly limited, and for example, a method of applying a solution containing the above resin to the base material layer to form the anchor layer, a composition containing the above resin or the like as the anchor layer, and the like. Examples thereof include a method of forming an anchor layer on the surface of the base material layer by heating and melting with a T-die or the like.

Further, when forming the anchor layer, the above resin serving as the anchor layer and the adhesive composition of the present invention may be coextruded and the anchor layer and the adhesive layer may be integrally laminated on the surface of the base material layer. , The resin to be the anchor layer and the adhesive composition may be sequentially laminated on the surface of the base material layer, and when the base material layer is a plastic material, the plastic material to be the base material layer and the anchor The resin to be a layer and the adhesive composition may be co-extruded at the same time.

The adhesive adhesive composed of the adhesive adhesive composition of the present invention can be used for various purposes. Further, the adhesive layer made of the adhesive composition can be used alone as an adhesive sheet, and a laminate containing the adhesive layer can also be applied to various uses. For example, for protection such as surface protection, for masking, for bundling, for packaging, for office work, for labels, for decoration / display, for joining, for dicing tape, for sealing, for anticorrosion / waterproof, for medical / sanitary, glass Adhesive for shatterproofing, electrical insulation, holding and fixing electronic devices, semiconductor manufacturing, optical display film, adhesive type optical film, electromagnetic wave shield, or sealing material for electrical and electronic parts , Adhesive tape, film or sheet and the like. Specific examples will be given below.

Adhesive adhesives, adhesive tapes, films, etc. for surface protection can be used for various materials such as metals, plastics, rubber, and wood. It can be used to protect the surface of automobile members and optical members. Examples of the automobile member include a painted outer panel, a wheel, a mirror, a window, a light, a light cover, and the like. The optical members include various image display devices such as liquid crystal displays, organic EL displays, plasma displays, and field emission displays; polarizing films, polarizing plates, retardation plates, light guide plates, diffusers, and optical disk constituent films such as DVDs; electrons. -Precision fine coated face plates for optical applications can be mentioned.

Applications such as adhesives for masking, tapes and films include masking during manufacturing of printed substrates and flexible printed substrates; masking during plating and soldering with electronic devices; manufacturing of vehicles such as automobiles, vehicles and construction. Examples include painting, printing, and masking when civil work is closed.

Bundling applications include wire harnesses, electric wires, cables, fibers, pipes, coils, windings, steel materials, ducts, plastic bags, foods, vegetables, flowers and the like.
Examples of packaging applications include heavy-duty packaging, export packaging, corrugated cardboard box sealing, and can seals.

Examples of office use include general-purpose office work, sealing, book repair, drafting, memos, and the like.
Labels include prices, product displays, tags, POPs, stickers, stripes, nameplates, decorations, advertisements, and the like.

The above labels include paper, processed paper (paper that has been subjected to aluminum vapor deposition processing, aluminum laminating processing, varnish processing, resin processing, etc.), synthetic paper, and other paper; made of cellophane, plastic material, cloth, wood, and metal. Examples thereof include labels using a film or the like as a base material. Specific examples of the base material include high-quality paper, art paper, cast paper, thermal paper, foil paper; polyethylene terephthalate film, polyvinyl chloride film, OPP film, polylactic acid film, synthetic paper, synthetic paper thermal, and overlay. Examples include films. Above all, the adhesive composition of the present invention is excellent in transparency and weather resistance, and can be suitably used for a label using a base material made of a transparent material. Further, since the adhesive composition of the present invention is less discolored with time, it can be suitably used for a thermal label using thermal paper or synthetic paper thermal as a base material.

Examples of the adherend of the label include plastic products such as plastic bottles and foamed plastic cases; paper and cardboard products such as cardboard boxes; glass products such as glass bottles; metal products; and other inorganic material products such as ceramics. Be done.

The label made of a laminate containing an adhesive layer made of the adhesive composition of the present invention has little adhesion enhancement during storage at a temperature slightly higher than room temperature (for example, 40 ° C), and can be peeled off without adhesive residue after use. it can. Moreover, it can be attached to the adherend even at a low temperature (-40 to + 10 ° C.) and will not peel off even when stored at a low temperature (-40 to + 10 ° C.).

Examples of decorative / display applications include danger display stickers, line tapes, wiring markings, phosphorescent tapes, reflective sheets, and the like.
Adhesive optical film applications include, for example, polarizing films, polarizing plates, retardation films, viewing angle enlargement films, brightness improving films, antireflection films, antiglare films, color filters, light guide plates, diffusion films, prism sheets, electromagnetic waves. Adhesive layer on at least part or all of one or both sides of a shield film, near-infrared absorbing film, functional composite optical film, ITO bonding film, impact resistance imparting film, brightness improving film, visibility improving film, etc. An optical film or the like formed by the above can be mentioned. Such an adhesive adhesive type optical film includes a film in which an adhesive layer made of the adhesive composition of the present invention is formed on a protective film used for surface protection of the optical film. The adhesive adhesive type optical film is suitably used for various image display devices such as liquid crystal display devices, PDPs, organic EL display devices, electronic papers, game machines, and mobile terminals.

Examples of electrical insulation applications include protective coating or insulation of coils, interlayer insulation of motors and transformers, and the like.
Examples of applications for holding and fixing electronic devices include carrier tape, packaging, fixing of cathode ray tubes, splicing, and rib reinforcement.

Examples of semiconductor manufacturing include protection of silicon wafers.
Examples of the bonding application include various bonding fields, automobiles, trains, electric devices, printing plate fixing, construction, name plate fixing, general household use, rough surface, uneven surface, bonding to curved surfaces and the like.

Examples of sealing applications include sealing for heat insulation, vibration isolation, waterproofing, moisture proofing, soundproofing or dustproofing.
Examples of anticorrosion / waterproof applications include anticorrosion of gas and water pipes, anticorrosion of large diameter pipes, and anticorrosion of civil engineering buildings.

For medical and hygiene applications, analgesic and anti-inflammatory agents (plaster, pap), ischemic heart disease therapeutic agents, female hormone replacement agents, bronchial dilators, cancer pain relievers, quitting aids, adhesive patches, antipruritic patches, Percutaneous absorbents such as keratin softeners; First aid adhesive plasters (with bactericides), surgical dressing / surgical tapes, adhesive plasters, hemostatic bonds, human excrement treatment equipment tapes (artificial anal fixation tapes), suture tapes, antibacterial tapes , Fixed taping, self-adhesive bandage, oral mucosa sticking tape, sports tape, hair removal tape, etc.; beauty applications such as face pack, eye moisturizing sheet, keratin peeling pack; cooling sheet, thermal cairo, dustproof, Examples include waterproofing and pest catching.
Examples of encapsulants for electronic and electrical parts include liquid crystal monitors and solar cells.

Hereinafter, the present invention will be specifically described with reference to Examples, Comparative Examples and the like, but the present invention is not limited to the following examples. In Synthesis Examples 1 to 10 shown below, the monomers and other compounds were dried and purified by a conventional method, degassed with nitrogen, and used. In addition, the transfer and supply of the monomer and other compounds to the reaction system was carried out in a nitrogen atmosphere.

Various physical properties of Examples and Comparative Examples were measured or evaluated by the following methods.
(1) Acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5), and acrylic diblock copolymers (III-1) to (III). The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of -2) were determined by GPC as standard polystyrene-equivalent molecular weights.
・ Equipment: GPC equipment "HLC-8020" manufactured by Tosoh Corporation
-Separation column: "TSKgel GMHXL", "G4000HXL" and "G5000HXL" manufactured by Tosoh Corporation are connected in series.-Eluent: tetrahydrofuran-Eluent flow rate: 1.0 ml / min-Column temperature: 40 ° C.
-Detection method: Differential refractometer (RI)

(2) Acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5), and acrylic diblock copolymers (III-1) to (III). The content of each polymer block in -2) was ^{determined by 1} H-NMR measurement.
・ Equipment: Nuclear magnetic resonance equipment "JNM-ECX400" manufactured by JEOL Ltd.
・ Solvent: Deuterated chloroform
In ¹ H-NMR spectrum, signals in the vicinity of 3.6ppm and 4.0ppm, respectively, the ester group of methyl methacrylate unit (-O-CH ₃₎ and acrylic acid ester unit of the ester group (-O-C H ₂ It _{is assigned to −CH 2} −CH ₂ −CH ₃ or −O−C H ₂ −CH (−CH ₂ −CH ₃ ) −CH ₂ −CH ₂ −CH ₂ −CH ₃ ), and is copolymerized by the ratio of the integrated values. The content of the polymer component was determined.

(3) The polymer block (B) in the acrylic triblock copolymers (I-1) to (I-3) and the polymer block (F) in the acrylic diblock copolymer (III-2). The ratio of the monomers constituting the above was ^{determined by 1} H-NMR measurement.
・ Equipment: Nuclear magnetic resonance equipment "JNM-ECX400" manufactured by JEOL Ltd.
^{-Solar: In the 1} H-NMR spectrum of the mixed monomer used for the polymerization of the dehydrided chloroform polymer block (B) or (F), the signals around 4.1 ppm and 4.2 ppm are acrylic acids, respectively. N-butyl ester group (-O-C H _2- CH _2- CH _2- CH ₃ ) and 2-ethylhexyl acrylate ester group (-O-C H _2- CH (-CH ₂ -CH ₃ )- It belongs to CH ₂ −CH ₂ −CH ₂ −CH ₃ ), and the content by the molar ratio of each monomer is determined by the ratio of the integrated values, and this is converted into the mass ratio based on the molecular weight of the monomer unit. Converted and used as the mass ratio of the monomers constituting the polymer block (B) or (F).

(4) Compatibility The compatibility was evaluated by the appearance 24 hours after the production of the adhesive tape having the adhesive layer having a thickness of 25 μm produced by the method described later. The adhesive tape that was colorless and transparent and uniform was designated as "A" (compatibility: good), and the adhesive tape that showed unevenness or cloudiness was designated as "B" (compatibility: bad).

(5) Bleed 24 hours after the production of the adhesive tape having the adhesive layer having a thickness of 25 μm produced by the method described later, the liquid material oozes out or adheres from the surface of the adhesive layer of the adhesive tape. It was evaluated by the decrease in tack due to the bleeding of the imparting resin. If no decrease in tack due to bleeding of the liquid material from the surface of the adhesive layer or bleeding of the adhesive resin is observed 24 hours after the production of the adhesive tape, "None", and 24 hours after the production, the liquid material from the tape surface. When the tack was reduced due to the bleeding of the adhesive or the bleeding of the tackifying resin, it was judged as "Yes".

(6) Adhesive strength A stainless steel (SUS304) plate (bright annealed product) or polyethylene (PE) plate with a width of 25 mm and a length of 100 mm of an adhesive tape having an adhesive layer with a thickness of 25 μm produced by the method described below. The sample was stored at room temperature for 24 hours, and then peeled off at a speed of 300 mm / min at 23 ° C. in the direction of 180 ° for evaluation. Those having a measured value of 2N / 25 mm or more were designated as "A", and those having a measured value of less than 2N / 25 mm were designated as "B".

(7) Tack The resistance when the thumb was pressed against the surface of the adhesive layer of the adhesive tape having a thickness of 25 μm prepared by the method described later at 25 ° C. and peeled off was sensory evaluated as a feeling of tack. Here, the one having a tacky feeling is designated as "A", and it is shown that it is suitable as a pressure-sensitive adhesive. On the other hand, those having no tack feeling were designated as "B" and were not suitable as pressure-sensitive adhesives.

(8) Workability The workability was evaluated as follows. That is, when the adhesive composition of the present invention is kneaded with a kneader, the one that can be kneaded with the kneader set at 145 ° C. is "A" (processability: good), and the one that cannot be kneaded due to high viscosity is "". B ”(processability: bad).

(9) Thermal stability Thermal stability is determined by evaluating the color change of the appearance before and after heat treatment at 180 ° C. for 3 hours at 180 ° C. for an adhesive tape having a 25 μm-thick adhesive layer prepared by the method described later. It was. When the color change could not be confirmed on the appearance before and after the heat treatment, it was evaluated as "A" (thermal stability: good), and when the color change could be confirmed, it was evaluated as "B" (thermal stability: bad).

<< Synthesis Examples 1 to 10 >>
<< Synthesis Example 1 >> [Synthesis of acrylic triblock copolymer (I-1)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 1035 g of toluene and 31.9 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 41.7 g of a toluene solution containing 21.0 mmol of aluminum, and 2.41 g of a cyclohexane solution of sec-butyllithium containing 4.11 mmol of sec-butyllithium. added.
(2) Subsequently, 28.5 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 210 g of a mixture of n-butyl acrylate / 2-ethylhexyl acrylate (mass ratio 50/50) was added dropwise over 2 hours, and after the addition was completed. The mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 31.8 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After adding 13.6 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 250 g of an acrylic triblock copolymer (I-1).

<< Synthesis Example 2 >> [Synthesis of acrylic triblock copolymer (I-2)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 1044 g of toluene and 34.8 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Toluene solution containing 17.1 mmol of aluminum was added, and 1.67 g of cyclohexane solution of sec-butyllithium containing 2.84 mmol of sec-butyllithium was added. added.
(2) Subsequently, 22.0 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., and 214 g of a mixture of n-butyl acrylate / 2-ethylhexyl acrylate (mass ratio 50/50) was added dropwise over 2 hours, and after the addition was completed. The mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 33.8 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After adding 10.7 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the white precipitate was collected and dried to obtain 250 g of an acrylic triblock copolymer (I-2).

<< Synthesis Example 3 >> [Synthesis of acrylic triblock copolymer (I-3)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 1038 g of toluene and 43.5 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 37.4 g of a toluene solution containing 18.8 mmol of aluminum, and 2.90 g of a cyclohexane solution of sec-butyllithium containing 4.95 mmol of sec-butyllithium. added.
(2) Subsequently, 25.4 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., and 215 g of a mixture of n-butyl acrylate / 2-ethylhexyl acrylate (mass ratio 50/50) was added dropwise over 2 hours. The mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 29.4 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After adding 13.3 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the white precipitate was recovered and dried to obtain 250 g of an acrylic triblock copolymer (I-3).

<< Synthesis Example 4 >> [Synthesis of acrylic triblock copolymer (II-1)]
(1) A two-way cock was attached to a 2 L three-necked flask, the inside was replaced with nitrogen, and then 939 g of toluene and 21.8 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 32.4 g of a toluene solution containing 16.3 mmol of aluminum, and add 1.59 g of a cyclohexane solution of sec-butyllithium containing 2.72 mmol of sec-butyllithium. added.
(2) Subsequently, 21.7 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 273 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 30.2 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After 10.2 g of methanol was added to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 310 g of an acrylic triblock copolymer (II-1).

<< Synthesis Example 5 >> [Synthesis of acrylic triblock copolymer (II-2)]
(1) A two-way cock was attached to a 2 L three-necked flask, the inside was replaced with nitrogen, and then 939 g of toluene and 21.8 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 32.4 g of a toluene solution containing 16.3 mmol of aluminum, and further add 1.00 g of a cyclohexane solution of sec-butyllithium containing 1.70 mmol of sec-butyllithium. added.
(2) Subsequently, 15.1 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 289 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 19.6 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After 10.0 g of methanol was added to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 300 g of an acrylic triblock copolymer (II-2).

<< Synthesis Example 6 >> [Synthesis of acrylic triblock copolymer (II-3)]
(1) A two-way cock was attached to a 2 L three-necked flask, the inside was replaced with nitrogen, and then 939 g of toluene and 21.8 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 32.4 g of a toluene solution containing 16.3 mmol of aluminum, and add 1.70 g of a cyclohexane solution of sec-butyllithium containing 2.90 mmol of sec-butyllithium. added.
(2) Subsequently, 29.0 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 240 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 41.0 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After 10.0 g of methanol was added to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 280 g of an acrylic triblock copolymer (II-3).

<< Synthesis Example 7 >> [Synthesis of acrylic triblock copolymer (II-4)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 868 g of toluene and 43.4 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 60.0 g of a toluene solution containing 40.2 mmol of 6-di-t-butyl-4-methylphenoxy) aluminum is added, and 2.89 g of a cyclohexane solution of sec-butyllithium containing 5.00 mmol of sec-butyllithium is added. added.
(2) Subsequently, 35.9 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 240 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 35.9 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After adding 3.50 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 300 g of an acrylic triblock copolymer (II-4).

<< Synthesis Example 8 >> [Synthesis of acrylic triblock copolymer (II-5)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 868 g of toluene and 43.4 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 80.0 g of a toluene solution containing 40.2 mmol of aluminum, and add 3.18 g of a cyclohexane solution of sec-butyllithium containing 5.50 mmol of sec-butyllithium. added.
(2) Subsequently, 46.2 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 210 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) Further, 43.9 g of methyl methacrylate was added thereto, and the mixture was stirred overnight at room temperature.
(5) After adding 13.3 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a white precipitate. Then, the liquid precipitate was collected and dried to obtain 280 g of an acrylic triblock copolymer (II-5).

<< Synthesis Example 9 >> [Synthesis of acrylic diblock copolymer (III-1)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 903 g of toluene and 58.3 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 36.2 g of a toluene solution containing 18.2 mmol of aluminum, and add 4.27 g of a cyclohexane solution of sec-butyllithium containing 7.28 mmol of sec-butyllithium. added.
(2) Subsequently, 26.8 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., 378 g of n-butyl acrylate was added dropwise over 2 hours, and after the addition was completed, the mixture was stirred at −30 ° C. for 5 minutes.
(4) After adding 15.0 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a liquid precipitate. Then, the liquid precipitate was collected and dried to obtain 380 g of an acrylic diblock copolymer (III-1).

<< Synthesis Example 10 >> [Synthesis of acrylic diblock copolymer (III-2)]
(1) After attaching a three-way cock to a 2 L three-necked flask and replacing the inside with nitrogen, 903 g of toluene and 58.3 g of 1,2-dimethoxyethane were added while stirring at room temperature, followed by isobutylbis (2,). 6-di-t-Butyl-4-methylphenoxy) Add 36.2 g of a toluene solution containing 18.2 mmol of aluminum, and add 4.27 g of a cyclohexane solution of sec-butyllithium containing 7.28 mmol of sec-butyllithium. added.
(2) Subsequently, 26.8 g of methyl methacrylate was added thereto. The reaction solution was initially colored yellow, but became colorless after stirring at room temperature for 60 minutes.
(3) Subsequently, the internal temperature of the polymerization solution was cooled to −30 ° C., and 378 g of a mixture of n-butyl acrylate / 2-ethylhexyl acrylate (mass ratio 50/50) was added dropwise over 2 hours. The mixture was stirred at −30 ° C. for 5 minutes.
(4) After adding 15.0 g of methanol to stop the polymerization reaction, the obtained reaction solution was poured into 15 kg of methanol to precipitate a liquid precipitate. Then, the liquid precipitate was collected and dried to obtain 380 g of an acrylic diblock copolymer (III-2).

The acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 10 above, and the acrylic diblock copolymer (III). -1) to (III-2) weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn), block structure, content of each polymer block, polymer block (B), (D) or (F) The configuration of is shown in Table 1.

In Examples , Reference Examples and Comparative Examples, the following were used as the tackifier resin and the plasticizer.
Adhesive-imparting resin:
-Product name "Ysertack 311" manufactured by Euro Yser, rosin ester, softening point 88 ° C.
-Product name "Foral 85" manufactured by Pinova, hydrogenated rosin ester, softening point 85 ° C.
-Product name "Pensel D125" manufactured by Arakawa Chemical Industry Co., Ltd., polymerized rosin ester, softening point 125 ° C
-Product name "Pensel D160" manufactured by Arakawa Chemical Industry Co., Ltd., polymerized rosin ester, softening point 160 ° C
-Product name "Foral AX" manufactured by Pinova, rosin acid, softening point 66 ° C.
-Product name "Clearon K4100" manufactured by Yasuhara Chemical Co., Ltd., hydrogenated aromatic-modified terpene resin, softening point 100 ° C.
-Product name "YS polyester T30" manufactured by Yasuhara Chemical Co., Ltd., terpene phenolic resin, softening point 30 ° C.
-Product name "YS polyester T160" manufactured by Yasuhara Chemical Co., Ltd., terpene phenolic resin, softening point 160 ° C.
-Product name "FTR6100" manufactured by Mitsui Chemicals, Inc., aromatic hydrocarbon resin, softening point 95 ° C.
-Product name "YS resin SX100" manufactured by Yasuhara Chemical Co., Ltd., aromatic hydrocarbon resin, softening point 100 ° C.
-Product name "Arkon M90" manufactured by Arakawa Chemical Industry Co., Ltd., hydrogenated petroleum resin, softening point 90 ° C.
-Product name "Arkon M100" manufactured by Arakawa Chemical Industry Co., Ltd., hydrogenated petroleum resin, softening point 100 ° C
-Product name "Arkon P100" manufactured by Arakawa Chemical Industry Co., Ltd., hydrogenated petroleum resin, softening point 100 ° C
Plasticizer:
・ Product name “DOP” manufactured by Shin Nihon Rika Co., Ltd., bis (2-ethylhexyl) phthalate ・ Product name “Eastman 168SG” manufactured by Eastman, bis (2-ethylhexyl) terephthalate ・ Product name “ATBC” manufactured by Asahi Kasei Finechem Co., Ltd., acetyl Tributyl citrate, trade name "K-FLEX DP" made by Kalama chemical, esterified product of benzoic acid and dipropylene glycol, trade name "Millyl 105" made by Polychem, acrylic oligomer, trade name "UP1010" made by Toa Synthetic Co., Ltd., acrylic Oligomer

<< Examples 1-8, 10, 11, 17-25, Reference Examples 9, 12-16, 26-29, Comparative Examples 1-9 >>
Table 2A below shows the acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 8 and the tackifier resin. A toluene solution was prepared by dissolving in toluene at the mass ratio shown in ~ 2C and containing a pressure-sensitive adhesive composition having a concentration of 40% by mass. This is coated on a polyethylene terephthalate film (Toyobo ester film E5000, thickness 50 μm) with a coater so that the thickness of the adhesive layer after drying is 25 μm, and then the film is coated at 60 ° C. for 30 minutes. The adhesive tape was prepared by drying and heat-treating with. In the evaluation of the prepared adhesive tape, when it was necessary to attach it to the adherend, a 2 kg roller was reciprocated twice at a speed of 10 mm / sec to attach it, and the adhesive strength was evaluated. The results are shown in Tables 2A-2C below.

Further, the acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 8 and the tackifier resin are described below. A viscous adhesive composition was prepared by melt-kneading at the mass ratios shown in Tables 2A to 2C of the above. The processability of the obtained adhesive adhesive was evaluated by the above method. The results are shown in Tables 2A-2C below.

<< Reference Examples 30 to 52, Comparative Examples 10 to 17 >>
The acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 8 and the tackifier resin and the plasticizer Was used in the mass ratios shown in Tables 3A to 3B below to prepare a viscous adhesive composition in the same manner as in Example 1. The evaluation of the obtained adhesive adhesive was carried out in the same manner as in Example 1. The results are shown in Tables 3A-3B.

<< Reference Examples 53 to 72, Comparative Examples 18 to 26 >>
The acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 10 above, and the acrylic diblock copolymer (III). Using the tackifier resins -1) to (III-2) in the mass ratios shown in Tables 4A to 4B below, a viscous adhesive composition was prepared in the same manner as in Example 1. The evaluation of the obtained adhesive adhesive was carried out in the same manner as in Example 1. The results are shown in Tables 4A-4B.

<< Reference Examples 73 to 94, Comparative Examples 27 to 39 >>
The acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) obtained in Synthesis Examples 1 to 10 above, and the acrylic diblock copolymer (III). -1) to (III-2), the tackifier resin and the plasticizer were used in the mass ratios shown in Tables 5A to 5C below to prepare a viscous adhesive composition in the same manner as in Example 1. .. The evaluation of the obtained adhesive adhesive was carried out in the same manner as in Example 1. The results are shown in Tables 5A-5C.

From the results of Tables 2A to 5C, acrylic triblock copolymers (I-1) to (I-3) and (II-1) to (II-5) satisfying the provisions of the present invention, tackifying resins, etc. In Examples 1 to 94, which are contained, the compatibility with the tackifier resin and / or the plasticizer is excellent, there is no bleeding of the tackifier resin and / or the plasticizer, and the adhesive strength to the high-polarity adherend and the low-polarity cover are low. It can be seen that it is excellent in both adhesive strength to the body, has tack, and is also excellent in hot melt processability and thermal stability.

Further, from the results of Tables 2A to 5C, when the tackifier resin and / or the plasticizer is blended in a larger amount than specified in the present invention, problems such as deterioration of compatibility and bleeding occur. When it contains only one of the acrylic triblock copolymers (I) and (II), it is inferior in adhesive strength to high-polarity adherends, adhesive strength to low-polarity adherends, or both. , Tack also deteriorates, and compatibility may be inferior. By containing the acrylic diblock copolymer (III), the balance of adhesive strength, tackiness, processability and thermal stability is improved, but if it is contained in excess of the specified amount of the present invention, there is bleeding and adhesion is achieved. Inferior in power. When it does not contain the tackifier resin, it is inferior in adhesive strength, tackiness and processability. If the softening point of the tackifier resin exceeds 110 ° C., the processability is inferior. When the softening point of the tackifier resin is less than 110 ° C., particularly less than 100 ° C., the workability is improved.

The adhesive composition of the present invention is bleed-free and has excellent transparency, compatibility, hot melt processability, cohesive force, tackiness, and holding power. Further, according to the present invention, it is possible to provide an adhesive adhesive and an adhesive product having an excellent balance between the adhesive force to a high-polarity adherend and the adhesive force to a low-polarity adherend.

Claims (4)

(I) It has two polymer blocks (A1) and (A2) composed of methacrylic acid ester units and one polymer block (B) composed of acrylic acid ester units.
The acrylic ester unit constituting the polymer block (B) is an acrylic represented by the general formula CH ₂ = CH-COOR ¹ (1) (in the formula, R ¹ represents an organic group having 4 to 6 carbon atoms). It consists of an acid ester (1) unit and _{an acrylic ester (2) unit represented by the general formula CH 2} = CH-COOR ² (2) (in the formula, R ² represents an organic group having 7 to 12 carbon atoms).
The mass ratio (1) / (2) of the acrylic acid ester (1) unit and the acrylic acid ester (2) unit in the polymer block (B) is 40/60 to 60/40.
It has a (A1)-(B)-(A2) block structure, has a weight average molecular weight (Mw) of 40,000 to 200,000, and is a polymer block (A1) in the acrylic triblock copolymer (I). ) And (A2), an acrylic triblock copolymer (I) having a total content of 35% by mass or less.
(Ii) It has two polymer blocks (C1) and (C2) composed of methacrylic acid ester units and one polymer block (D) composed of acrylic acid ester units.
The acrylic acid ester unit constituting the polymer block (D) is an acrylic represented by the general formula CH ₂ = CH-COOR ³ (3) (in the formula, R ³ represents an organic group having 4 to 12 carbon atoms). It consists of an acid ester (3) unit (however, the polymer block (D) is different from the polymer block (B)).
It has a (C1)-(D)-(C2) block structure, has a weight average molecular weight (Mw) of 50,000 to 250,000, and is a polymer block (C1) in an acrylic triblock copolymer (II). ) and total acrylic triblock copolymer content is more than 35 wt% (II), and (iii ') a softening point contained only 96 ° C. the following tackifying resin (C2),
The ratio of the acrylic triblock copolymer (I) to the total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II) is 20 to 80% by mass.
Total relative to 100 parts by weight, the tackifier resin 1 to 300 parts by weight adhesive composition containing the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). The adhesive composition according to claim 1, wherein the acrylic triblock copolymer (I) has a weight average molecular weight (Mw) of 50,000 to 180,000. The invention according to claim 1 or 2, wherein the tackifier resin is contained in an amount of 10 to 250 parts by mass based on a total of 100 parts by mass of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II). Adhesive composition. Claim 1 in which the ratio of the acrylic triblock copolymer (I) to the total of the acrylic triblock copolymer (I) and the acrylic triblock copolymer (II) is 25 to 75% by mass. The adhesive composition according to any one of 3 to 3.