JP2022098709A - Pressure sensitive adhesive tape and pressure sensitive adhesive - Google Patents

Abstract

To provide a pressure sensitive adhesive tape and a pressure sensitive adhesive each having excellent adhesive force particularly to a polyolefin-based foam.SOLUTION: A pressure sensitive adhesive tape is provided, having a pressure sensitive adhesive layer containing a styrene-isoprene block copolymer (A) and a tackifying resin (B), wherein the styrene-isoprene block copolymer (A) contains a styrene-isoprene diblock copolymer (a1) and a styrene-isoprene triblock copolymer (a2), a content of the tackifying resin (B) is 75 pts.mass or more with respect to 100 pts.mass of the styrene-isoprene block copolymer (A), the tackifying resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2), and a blending ratio (b1:b2) of the petroleum resin (b1) to the rosin-based resin (b2) is within a range of 2:1 to 10:1. A pressure sensitive adhesive enabling formation of the pressure sensitive adhesive layer is also provided.SELECTED DRAWING: None

Description

The present invention relates to an adhesive and an adhesive tape that can be used for fixing parts constituting electronic devices and the like.

Rubber-based adhesives containing styrene-isoprene block copolymers have good initial adhesive strength to adherends such as polyethylene and polypropylene, and therefore, for example, parts constituting electronic devices and automobile interior / exterior members. It is suitably used for fixing.

For example, Patent Document 1 describes a pressure-sensitive adhesive tape using a rubber-based pressure-sensitive adhesive, for example, a double-sided pressure-sensitive adhesive tape having rubber-based pressure-sensitive adhesive layers on both sides of a base material, wherein the rubber-based pressure-sensitive adhesive layer is defined as a styrene-based resin. A double-sided adhesive tape made of the adhesive-imparting resin of No. 1 is disclosed.

Although it is disclosed that the double-sided adhesive tape can exhibit good adhesiveness to a member containing a polyolefin resin, there is room for further improvement in adhesiveness. In particular, in the case of bonding a foam member or a rigid member that easily disperses stress, it is not possible to sufficiently pressurize the member at the time of bonding, and it is difficult to obtain sufficient adhesion between the adhesive tape and the member. There was a concern about poor adhesion such as easy interface peeling with.

Japanese Unexamined Patent Publication No. 2019-52280

An object to be solved by the present invention is to provide an adhesive tape and an adhesive having excellent adhesive strength to an adherend containing a polyolefin-based resin such as polyethylene or polypropylene, particularly a polyolefin-based foam.

In order to solve the above problems, the present invention contains a styrene-isoprene block copolymer (A) and a tackifier resin (B), and the styrene-isoprene block copolymer (A) is a styrene-isoprene. It contains a diblock copolymer (a1) and a styrene-isoplentry block copolymer (a2), and the content of the tackifier resin (B) is 100 parts by mass of the styrene-isoprene block copolymer (A). The pressure-sensitive adhesive resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2), and is a blend of the petroleum resin (b1) and the rosin-based resin (b2). Provided is an adhesive tape characterized by having an adhesive layer having a ratio (b1: b2) in the range of 2: 1 to 10: 1.

The present invention also provides a pressure-sensitive adhesive capable of forming the pressure-sensitive adhesive layer.

The pressure-sensitive adhesive tape and pressure-sensitive adhesive of the present invention have excellent adhesive strength to an adherend containing a polyolefin-based resin such as polyethylene or polypropylene, particularly a polyolefin-based foam.

The pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer having a predetermined composition. Hereinafter, the pressure-sensitive adhesive tape of the present invention and the pressure-sensitive adhesive used for forming the above-mentioned pressure-sensitive adhesive will be described.

1. 1. Adhesive layer The adhesive layer of the pressure-sensitive adhesive tape of the present invention is a styrene-isoprene block copolymer (A) containing a styrene-isopregen block copolymer (a1) and a styrene-isoprelent block copolymer (a2). ) And a pressure-sensitive adhesive containing the pressure-sensitive adhesive resin (B). The pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer in the present invention have a content of the pressure-sensitive adhesive resin (B) of 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A). It is characterized by being. Further, the tackifier resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2), and the blending ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2). Is in the range of 2: 1 to 10: 1.

The polyolefin-based resin is formed by the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer containing the specific pressure-sensitive resin (A) and the specific pressure-sensitive adhesive resin (B) in a predetermined blending amount. It is possible to exhibit high adhesive (adhesive) strength to an adherend as a main component, particularly a polyolefin-based foam which easily disperses stress and makes it difficult to obtain sufficient adhesion.

Further, since the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer have the above-mentioned specific composition, in addition to high adhesiveness to the polyolefin-based foam, they can be used in an environment exposed to heat. It is possible to exhibit high holding power with less occurrence of interfacial peeling over time, and to have excellent thermal durability.

-Styrene-isoprene block copolymer (A)-
As the styrene-isoprene block copolymer (A) contained in the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer in the present invention, those having a structural unit represented by the following chemical formula (1) are used. Specifically, the structural unit is preferably a structure derived from styrene.

The styrene-isoprene block copolymer (A) contains 10% by mass to 80% by mass of the structural unit represented by the following chemical formula (1) with respect to the total mass of the styrene-isoprene block copolymer (A). It is preferable to use the one having a range of 12 to 60% by mass, more preferably to use the one having a range of 12 to 60% by mass, and further preferably to use the one having a range of 15 to 40% by mass. It is even more preferable to use those having a range of%. As a result, adherence to an adherend containing a polyolefin-based resin as a main component, such as a polyolefin-based material or a polyester-based material, particularly to a polyolefin-based foam is high, and even better initial adhesiveness can be exhibited. This is because it can be used as a pressure-sensitive adhesive layer. Further, the pressure-sensitive adhesive layer having excellent thermal durability can be obtained.

The amount of the structural unit refers to the mass ratio of the structure represented by the above formula (1) to the total mass of the styrene-isoprene block copolymer (A).

In the present invention, the styrene-isoprene block copolymer (A) contains the styrene-isoprene block copolymer (a1) and the styrene-isoprene block copolymer (a2). It is preferable that the styrene-isoprene block copolymer (A) is a mixture of the styrene-isoprene block copolymer (a1) and the styrene-isoprene block copolymer (a2). As a method for producing the styrene-isoprene block copolymer (A), which is a mixture of the above (a1) and (a2), a method of separately producing the above (a1) and (a2) and then mixing them. Alternatively, polystyrene and polyisoprene can be produced by polymerizing styrene and isoprene separately, and can be produced by reacting them to obtain a mixture of the above (a1) and (a2).

The ratio of the styrene-isopregen block copolymer (a1) to the total amount of the styrene-isoprene block copolymer (A) is preferably in the range of 10% by mass to 80% by mass, and more preferably 15% by mass to 75% by mass. It is more preferably in the range of%, more preferably in the range of 20% by mass to 70% by mass, and even more preferably in the range of 25% by mass to 65% by mass. Further, in the mixture in which the styrene-isoprene block copolymer (A) is composed of the styrene-isopregen block copolymer (a1) and the styrene-isoplentry block copolymer (a2), the styrene-isoprene block copolymer is also used. The polymer (A) is a styrene-isopregen block copolymer (a1) with respect to the total mass of the styrene-isopregen block copolymer (a1) and the styrene-isoprelent block copolymer (a2). It is preferable to use a polymer contained in the range of 10% by mass to 80% by mass, particularly preferably a polymer contained in the range of 15% by mass to 75% by mass, and a range of 20% by mass to 70% by mass. It is more preferable to use the polymer contained in the above, and even more preferably to use it in the range of 25% by mass to 65% by mass. Adhesion mainly composed of polyolefin resins such as polyolefin materials and polyester materials, especially polyolefin foams, has high adhesion and can exhibit even better initial adhesiveness. This is because it can be used as a pressure-sensitive adhesive layer. Further, it is possible to obtain an adhesive layer having excellent thermal durability.

The styrene-isoprene block copolymer (A) has a weight average molecular weight (gel permeation chromatography, SC-8020 manufactured by Toso Co., Ltd.) measured in terms of standard polystyrene using a gel permeation chromatograph (GPC). It is preferable to use a high molecular weight column TSKgelGMHHR-H (solvent: tetrahydrofuran) in the range of 10,000 to 800,000, and more preferably to use one in the range of 30,000 to 500,000. It is even more preferable to use those in the range of 300,000. Within the above range, heat fluidity and compatibility at the time of solvent dilution can be ensured, so that workability in the manufacturing process is good, but the adherend containing a polyolefin resin as a main component, especially a polyolefin foam. On the other hand, it is more preferable to obtain an adhesive layer having excellent adhesion and high initial adhesiveness and further excellent thermal durability.

As the styrene-isoprene block copolymer (A), for example, a single structure such as a linear structure, a branched structure or a multi-branched structure can be used, but those having different structures are mixed and used. It is also possible. When a styrene-based resin rich in linear structure is used for the pressure-sensitive adhesive layer, the pressure-sensitive adhesive tape of the present invention is provided with excellent adhesive performance. On the other hand, a branched structure or a multi-branched structure in which a styrene block is arranged at the molecular end can have a pseudo-crosslinked structure and can give an excellent cohesive force, so that a high holding force can be given. .. It is preferable to mix and use these according to the required characteristics.

The styrene-isoprene block copolymer (A) is produced by, for example, polymerizing styrene and isoprene separately to produce polystyrene and polyisoprene, and reacting them to obtain a polymer by polymerizing styrene. After that, it can be produced by a conventionally known method such as a method of reacting the above polymer with isoprene.

-Adhesive-imparting resin (B)-
The tackifier resin (B) used for the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer in the present invention contains a petroleum resin (b1) and a rosin-based resin (b2), and the petroleum resin (b1). The compounding ratio (b1: b2) of the rosin-based resin (b2) to the above-mentioned rosin-based resin (b2) is in the range of 2: 1 to 10: 1. The content of the tackifier resin (B) is 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A). As a result, when used in combination with the above-mentioned specific styrene-based resin (A), the adhesion to an adherend containing a polyolefin-based resin as a main component, especially a polyolefin-based foam, is high, and even more excellent initial adhesiveness is obtained. Can be an adhesive layer capable of exerting the above.

The tackifier resin (B) may have a blending ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2) in the range of 2: 1 to 10: 1, among which 3: It is preferably in the range of 1 to 8: 1, more preferably in the range of 3: 1 to 6: 1, and even more preferably in the range of 4: 1 to 6: 1. This is because it is possible to enhance the adhesive force to an adherend containing a polyolefin-based resin as a main component, particularly a polyolefin-based foam. The compounding ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2) is a mass ratio.

Further, the content of the tackifier resin (B) contained in the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A). However, it is preferable to use it in the range of 80 parts by mass to 200 parts by mass, more preferably to use it in the range of 90 parts by mass to 180 parts by mass, and to use it in the range of 100 parts by mass to 160 parts by mass. It is more preferable to do so. By setting the blending amount of the tackifier resin (B) with respect to 100 parts by mass of the styrene-isoprene block copolymer (A) within the above range, an adherend containing a polyolefin resin as a main component, particularly a polyolefin foam, can be obtained. On the other hand, it is possible to provide a pressure-sensitive adhesive layer having high adhesion and capable of exhibiting even better initial adhesiveness. Further, it is possible to obtain an adhesive layer having excellent thermal durability.

= Petroleum resin (b1) =
The petroleum resin (b1) preferably has a softening point of 80 ° C. or higher, particularly preferably in the range of 80 ° C. to 160 ° C., further preferably in the range of 90 ° C. to 150 ° C., and further excellent adhesiveness. From the viewpoint of excellent heat resistance, the temperature in the range of 100 ° C to 130 ° C is more preferable. Since the softening point of the petroleum resin (b1) is within the above range, the adhesiveness can be improved while maintaining the cohesive force of the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer. This is because it is possible to exhibit even better adhesiveness to the adherend as a component, especially the polyolefin-based foam. The softening point refers to a value measured by a method (dry-bulb method) specified in JIS K2207.

As the petroleum resin (b1), for example, a solid one at room temperature (23 ° C.) is preferably used, and an aliphatic petroleum resin, an aromatic petroleum resin, an aliphatic / aromatic copolymerized petroleum resin, and the like. Petroleum resins such as these hydrogen additives (for example, aliphatic petroleum resin, aliphatic / aliphatic petroleum resin), kumaron resin, and kumaron inden resin can be used. Above all, it is preferable that the petroleum resin (b1) is at least one selected from the group consisting of an aliphatic petroleum resin, an aromatic petroleum resin, and an aliphatic / aromatic copolymerized petroleum resin. This is because it has high compatibility with the styrene-isoprene block copolymer (A) and can exhibit excellent adhesion to an adherend containing a polyolefin-based resin as a main component, particularly a polyolefin-based foam. In addition, the pressure-sensitive adhesive can ensure excellent storage stability in a solution before forming the pressure-sensitive adhesive layer.

As the _prealiphatic petroleum resin, C5 petroleum resin obtained from pentene, pentadiene, isoprene and the like can be preferably used. For example, Escolets 1202, 1304, 1401 (manufactured by Tonen Chemical Corporation), Wing Tuck 95. (Manufactured by Goodyear Tire and Rubber Company), Quinton K100, R100, F100 (manufactured by Nippon Zeon Co., Ltd.), Pico Tac 95, Pico Pale 100 (manufactured by Rika Hercules) and the like can be used.

As the aromatic petroleum resin, _C9 petroleum resin obtained from indene, methyl inden, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene and the like can be preferably used.

As the aliphatic / aromatic copolymerized petroleum resin, a _C5 / _C9 petroleum resin which is a copolymer of the above _C5 petroleum resin and a _C9 petroleum resin can be preferably used. For example, Escolets 2101 (manufactured by Tonex), Quinton G115 (manufactured by Zeon Corporation of Japan), Harcotac 1149 (manufactured by Rika Hercules) and the like can be used.

The alicyclic petroleum resin can be obtained by hydrogenating the _C9 petroleum resin described above. For example, Escolets 5300 (manufactured by Tonex), Archon P-100 (manufactured by Arakawa Chemical Industries), Rigalite R101 (Rika). Fine Tech) etc. can be used.

The petroleum resin (b1) in the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer may be contained alone or in combination of two or more.

The petroleum resin (b1) is preferably contained in the largest amount among the tackifier resins (B) after satisfying the blending ratio with the rosin-based resin (b2), and the petroleum resin (b1) content is particularly adhesive. It is preferably 60% by mass or more, more preferably 75% by mass or more, and even more preferably 80% by mass or more in the total amount (100% by mass) of the applied resin (B). By including the amount of the petroleum resin (b1) having high compatibility with the styrene-isoprene block copolymer (A) in the above range, the adherend containing a polyolefin resin as a main component, particularly a polyolefin foam, can be obtained. This is because excellent adhesiveness can be exhibited. In addition, the pressure-sensitive adhesive can ensure storage stability in an excellent solution before forming the pressure-sensitive adhesive layer.

= Rosin resin (b2) =
Examples of the rosin-based resin (b2) include resins having a rosin skeleton, and examples thereof include unsaturated acid-modified rosin and phenol modified with unsaturated acids such as rosin resin, (meth) acrylic acid, fumaric acid, and maleic acid. Rosin phenol modified with phenols such as alkylphenol, rosin resin obtained by disproportionating rosin resin, rosin resin such as polymerized rosin resin obtained by polymerizing rosin resin; the above rosin resins and alcohols. Examples thereof include a rosin ester resin which is an esterified product of the above; a rosin resin and a rosin-based resin obtained by hydrogenating a rosin ester resin, a rosin hydride ester resin, and the like. Above all, the polymerized rosin resin is preferable in that it enhances the cohesive force of the pressure-sensitive adhesive layer and exhibits excellent adhesive performance to an adherend containing a polyolefin-based resin as a main component, particularly to a polyolefin-based foam.

The rosin-based resin (b2) preferably has a softening point of 80 ° C. or higher, particularly preferably in the range of 90 ° C. to 200 ° C., further preferably in the range of 100 ° C. to 180 ° C., and 110 ° C. to 160 ° C. The range of is more preferable. When the softening point of the rosin-based resin (b2) is within the above range, the cohesive force of the pressure-sensitive adhesive layer is enhanced, and excellent adhesion to an adherend containing a polyolefin-based resin as a main component, especially a polyolefin-based foam. This is because it exhibits performance. The softening point refers to a value measured by a method (dry-bulb method) specified in JIS K2207.

The rosin-based resin (b2) in the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer may be contained alone or in combination of two or more.

= Other adhesive resin (b3) =
The pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer in the present invention contain at least a petroleum resin (b1) and a rosin-based resin (b2) as the pressure-sensitive adhesive resin (B), but the above-mentioned resin (b1) and the resin. A resin (b3) other than (b2) may be contained. Examples of the resin (b3) include known tackifier resins, and examples thereof include terpene-based resins, phenol-based resins, and ketone-based resins. The content of the resin (b3) is preferably 20% by mass or less, more preferably 10% by mass or less, and 1% by mass or less in the total amount (100% by mass) of the tackifier resin (B). It is more preferable to have 0% by mass, that is, the tackifier resin (B) is substantially composed of one or more petroleum resins (b1) and one or more rosin-based resins (b2). It is preferable to be done.

-Arbitrary component-
In addition to the above-mentioned components, the pressure-sensitive adhesive layer and the pressure-sensitive adhesive constituting the above-mentioned pressure-sensitive adhesive layer in the present invention include other polymer components, a cross-linking agent, an antiaging agent generally usable for the pressure-sensitive adhesive, and ultraviolet rays. Additives such as absorbents, fillers, pigments and thickeners can be used as long as the effects of the present invention are not impaired. Above all, it is preferable to contain an anti-aging agent in order to further improve the excellent thermal durability.

As the antiaging agent, for example, using a phenolic antiaging agent can effectively improve the heat stability of the styrene-isoprene block copolymer (A), and as a result, good initial adhesion is achieved. It is preferable because it is possible to obtain a pressure-sensitive adhesive and a pressure-sensitive adhesive tape that maintain their properties and have even better thermal durability.

The phenolic antiaging agent is generally a phenolic compound having a steric hindrance group, and is typically a monophenolic type, a bisphenol type, or a polyphenol type. Specific examples include 2,6-di-t-butyl-4-methylphenol, 2,2'-methylenebis (4-methyl-6-t-butylphenol), and 2,2'-methylenebis (4-ethyl-6). -T-butylphenol), 4,4'-thiobis (6-t-butyl-3-methylphenol), 4,4'-butylidenebis- (3-methyl-6-t-butylphenol), tetrakis- [methylene-3 -(3'5'-di-t-butyl-4-hydroxyphenyl) propionate] Methyl, n-octadecyl-3- (4'-hydroxy-3'5'-di-t-butylphenyl) propionate, etc. alone Alternatively, two or more types can be used in combination.

The phenolic antiaging agent is preferably used in the range of 0.1 part by mass to 5 parts by mass with respect to 100 parts by mass of the styrene-isoprene block copolymer (A), and is preferably 0.5 parts by mass to 3 parts by mass. When used in the range of parts by mass, the thermal stability of the styrene-isoprene block copolymer can be effectively improved, and as a result, good initial adhesiveness is maintained and even better thermal durability is achieved. A pressure-sensitive adhesive and a pressure-sensitive adhesive tape can be obtained.

As the anti-aging agent, the above-mentioned phenol-based anti-aging agent and other anti-aging agents such as phosphorus-based anti-aging agent (also referred to as processing stabilizer), amine-based anti-aging agent, and imidazole-based anti-aging agent are used in combination. In particular, when the above-mentioned phenol-based anti-aging agent and phosphorus-based anti-aging agent are used in combination, a pressure-sensitive adhesive and a pressure-sensitive adhesive having even better thermal durability while maintaining good initial adhesiveness and may be used. Adhesive tape can be obtained. Since the phosphorus-based antiaging agent may slightly discolor (yellow) over time in a high temperature environment, the amount used should be a balance between the initial adhesiveness, thermal durability, and discoloration prevention. It is preferable to take it into consideration and set it appropriately.

-Adhesive layer-
As the pressure-sensitive adhesive layer in the present invention, it is preferable to use a pressure-sensitive adhesive layer having a thickness of 5 μm to 300 μm after drying, and it is preferable to use a pressure-sensitive adhesive layer having a thickness of 10 μm to 200 μm, mainly using a polyolefin resin. It is more preferable to obtain an adhesive tape having an even better initial adhesive force with respect to the adherend to be coated, particularly a polyolefin-based foam.

2. 2. Others-Structure and physical properties of adhesive tape-
The adhesive tape of the present invention may have the above-mentioned adhesive layer, and as a specific embodiment, the adhesive layer is laminated on one side or both sides of the base material (core) directly or via another layer. Examples thereof include a single-sided adhesive tape or a double-sided adhesive tape, a so-called base material-less double-sided adhesive tape composed of only an adhesive layer, and the like.

As the base material, for example, a plastic film such as a polyester film, a polypropylene film, a polyethylene film, a polyimide film, a foam body such as urethane, polyethylene, or a rubber, a non-woven fabric, a cloth, a metal foil, a paper, or the like is used. be able to. Above all, it is preferable to use a non-woven fabric because the adhesion to the uneven surface of the adherend is improved, and as a result, an adhesive tape capable of exhibiting an excellent initial adhesive force can be obtained.

As the non-woven fabric, those composed of fibers such as pulp, rayon, Manila hemp, acrylonitrile, nylon and polyester can be preferably used. Further, the nonwoven fabric may be impregnated with a thermoplastic resin such as viscose as a binder in order to improve the tensile strength.

Further, as the non-woven fabric, it is preferable to use one having a basis weight in the range of 5 g / m ² to 150 g / m ² , and one having a basis weight in the range of 10 g / m ² to 100 g / m ² . Is more preferable, and it is more preferable to use one in the range of 15 g / m ² to 50 g / m ² because the tensile strength of the adhesive tape can be improved and the sticking workability can be improved.

The base material preferably has a thickness of 10 μm to 300 μm, more preferably 30 μm to 200 μm, and 50 μm to 150 μm. It is more preferable because the tensile strength of the adhesive tape can be improved and the sticking workability can be improved.

The adhesive tape of the present invention may have a release liner on the surface of the adhesive layer. As the release liner, a known one can be used.

The adhesive tape of the present invention preferably has a total thickness in the range of 10 μm to 400 μm, and a tape having a total thickness in the range of 50 μm to 300 μm provides even better initial adhesive strength. It is preferable to obtain the provided adhesive tape. The total thickness of the adhesive tape does not include the thickness of the release liner.

Further, the adhesive tape of the present invention can be used, for example, in the form of a single-wafer or roll-shaped product.

It is preferable that the adhesive tape of the present invention is peeled off due to material destruction of the polyolefin-based foam when the T-shaped peel adhesive force with respect to the polyolefin-based foam is measured by the following measuring method. Further, the adhesive tape of the present invention preferably has a T-shaped peel adhesive force of 15 (N / 20 mm) or more, and is 18 (N / 20 mm) or more, as measured under the following measurement conditions. It is more preferably 20 (N / 20 mm) or more, and more preferably 20 (N / 20 mm) or more. This is because it can exhibit excellent adhesive force to an adherend containing a polyolefin-based resin as a main component, particularly a polyolefin-based foam.

(Measuring method)
An adherend made of a polyolefin-based foam is attached to both sides of the adhesive tape cut into a width of 20 mm and a length of 100 mm, and then the upper surface is reciprocated once with a 2 kg roller to be crimped under an environment of 60 ° C. One end of the adherend of the test piece was fixed to the lower chuck of the pulling device of the Tencilon tensile tester in an environment of 23 ° C. One end of the adherend is fixed to the upper chuck of the pulling device portion of the Tencilon tensile tester, the upper chuck is pulled at a speed of 50 mm / min, and the T-shaped peel adhesive force is measured.

More specifically, the T-shaped peel adhesive force of the adhesive tape is obtained by cutting the adhesive tape into a width of 20 mm and a length of 100 mm and covering both sides of the adhesive tape in a 23 ° C. and 50% RH atmosphere. A polyethylene (PE) -based foam is bonded as a body, and a 2 kg roller is pressure-bonded once back and forth, and then left in an environment of 60 ° C for 24 hours to adhere the adhesive tape and the PE foam to the test piece. Then, in an environment of 23 ° C., one end of the adherend of the test piece is fixed to the lower chuck of the pulling device portion of the tencilon tensile tester, and the end of the other adherend is subjected to the tencilon tensile test. It can be fixed to the upper chuck of the pulling device portion of the machine and the adhesive force (T-shaped peel adhesive force) measured value obtained by pulling the upper chuck at a speed of 50 mm / min can be obtained.

The adhesive tape of the present invention can exhibit a high adhesive (adhesive) force to a polyolefin-based foam that is particularly easy to disperse stress and difficult to obtain sufficient adhesion, but is not limited to the polyolefin-based foam and is a polyolefin. It is possible to exhibit high adhesive strength to various adherends containing based resin as a main component.

Further, the adhesive tape of the present invention can exhibit excellent thermal durability in addition to the above-mentioned effects. More specifically, the adhesive tape of the present invention preferably has a time to drop of 24 hours or more as measured by the following measuring method.

(Measuring method)
One of the adhesive surfaces of the adhesive tape is lined with a 25 μm thick polyethylene terephthalate film, cut to a width of 25 mm and a length of 100 mm, and then a clean and smooth surface stainless steel plate (360) at 23 ° C and 50% RH atmosphere. Place it on the surface of the hairline polishing process with water-resistant polishing paper so that the sticking area is 25 mm x 25 mm, and press the upper surface back and forth once with a 2 kg roller to crimp them, and in an environment of 23 ° C for 1 hour. A test piece was prepared by leaving it to stand, and the adhesive tape was made of stainless steel from the time when a load of 0.5 kg was applied to the adhesive tape in an environment of 40 ° C. with the stainless plate constituting the test piece fixed. Measure the time it takes to fall from the board.

-Manufacturing method of adhesive tape-
The method for producing the adhesive tape of the present invention can be appropriately selected depending on the laminated structure. As a manufacturing method, for example, a pressure-sensitive adhesive containing at least the above-mentioned styrene-isoprene block copolymer (A) and the pressure-sensitive adhesive resin (B) is applied to one or both sides of the above-mentioned base material and dried to form a pressure-sensitive adhesive layer. A method of producing by forming, a method of producing an adhesive layer by applying the above-mentioned adhesive to a release liner and drying it, and transferring it to one or both sides of a base material, the above-mentioned adhesive on a release liner. A method of producing an adhesive layer by applying and drying the adhesive layer, and attaching another release liner to the surface of the adhesive layer can be mentioned.

The pressure-sensitive adhesive contains a styrene-isoprene block copolymer (A) and a tackifier resin (B), and the styrene-isoprene block copolymer (A) is a styrene-isoprene block copolymer (a1). ) And the styrene-isoprene block copolymer (a2), and the content of the tackifier resin (B) is 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A). The tackifier resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2), and the compounding ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2) is 2. It is in the range of 1 to 10: 1. The details of the composition of the pressure-sensitive adhesive are as described in the above-mentioned section “1. Pressure-sensitive adhesive layer”.

Examples of the method of applying the pressure-sensitive adhesive include a method using a roll coater, a die coater, and the like.

The pressure-sensitive adhesive can contain an organic solvent in order to ensure good coating workability. The type of the organic solvent is not particularly limited, and an organic solvent generally used for rubber-based pressure-sensitive adhesives and the like can be used. The organic solvent contained in the pressure-sensitive adhesive should be used in the range of 40 parts by mass to 400 parts by mass with respect to 100 parts by mass in total of the styrene-isoprene block copolymer (A) and the tackifier resin (B). Is preferable. The pressure-sensitive adhesive layer in the pressure-sensitive adhesive tape is composed of a pressure-sensitive adhesive excluding an organic solvent.

-Use-
The adhesive tape of the present invention is suitable for manufacturing home appliances such as TVs, refrigerators, air conditioners, rice cookers, air purifiers, washing machines, vacuum cleaners, microwave ovens and personal computers, and OA equipment such as copiers and printers. Can be used for. Specifically, the adhesive tape of the present invention is used to fix parts such as a housing constituting the home appliance or OA equipment to a cushioning material or cushioning material such as foam, felt, or rubber, or the housing or the like. It can be used for fixing between parts.

Examples of the parts such as the housing include polyolefin-based resins, polyester-based resins, and the like. Examples of the cushioning material and cushioning material include polyolefin-based foams, polyester-based foams, felts, and non-woven fabrics.

Examples of the cushioning material and the cushioning material include a non-slip (grip member) located between the home electric appliance and the OA device and an installation surface such as a floor, and a member for suppressing micro-vibration of various parts.

Further, the adhesive tape of the present invention can be suitably used for fixing, for example, an automobile interior member such as an instrument panel, roof lining, or door trim to a cushioning material such as foam or felt, or a cushioning material.

Examples of the cushioning material and the cushioning material include a rubber material for filling a gap between a door and a window, a sound absorbing material, a vibration isolating material, and a non-slip material.

Further, the adhesive tape of the present invention can be suitably used, for example, for fixing a cushioning middle sole and an upper member of sports shoes.

The present disclosure is not limited to the above embodiment. The above embodiment is an example, and any one having substantially the same structure as the technical idea described in the claims of the present disclosure and having the same effect and effect is the present invention. Included in the technical scope of the disclosure.

Hereinafter, the present invention will be described in more detail by way of examples.

[Example 1]
(Preparation of adhesive A)
Styrene-isoprene block copolymer composition (A1) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), Styrene-isopregen block copolymer ratio to the total amount of the above composition (A1) is 40% by mass) 100 parts by mass, as a tackifier resin (b1) Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) 80 parts by mass of petroleum resin, softening point 115 ° C), 20 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C) as tackifying resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent A was obtained.

The pressure-sensitive adhesive A was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape A.

[Example 2]
(Preparation of adhesive B)
Styrene-isoprene block copolymer composition (A1) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), Styrene-isopregen block copolymer ratio to the total amount of the above composition (A1) is 40% by mass) 100 parts by mass, as a tackifier resin (b1) Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) 120 parts by mass of petroleum resin, softening point 115 ° C.), 30 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C.) as the tackifier resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent B was obtained.

The pressure-sensitive adhesive B was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape B.

[Example 3]
(Preparation of adhesive C)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). 80 parts by mass of petroleum resin, softening point 115 ° C), 20 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C) as tackifying resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent C was obtained.

The pressure-sensitive adhesive C was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape C.

[Example 4]
(Preparation of adhesive D)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). 120 parts by mass of petroleum resin, softening point 115 ° C.), 30 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C.) as the tackifier resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent D was obtained.

The pressure-sensitive adhesive D was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape D.

[Example 5]
(Preparation of adhesive E)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). 90 parts by mass of petroleum resin, softening point 115 ° C), 15 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C) as tackifying resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent E was obtained.

The pressure-sensitive adhesive E was applied on a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape E.

[Example 6]
(Preparation of adhesive F)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). Styrenic petroleum resin, softening point 115 ° C.) 75 parts by mass, Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C.) 15 parts by mass as tackifier resin (b2), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent F was obtained.

The pressure-sensitive adhesive F was applied on a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape F.

[Comparative Example 1]
(Preparation of adhesive G)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). Styrene petroleum resin, softening point 115 ° C.) 70 parts by mass, adhesive resin (b2) 5 parts by mass of Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C), aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent G was obtained.

The pressure-sensitive adhesive G was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape F.

[Comparative Example 2]
(Preparation of adhesive H)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). Mix 75 parts by mass of petroleum resin, softening point 115 ° C., and 1 part by mass of antioxidant (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane). Then, the pressure-sensitive adhesive H was obtained by dissolving it in 100 parts by mass of toluene as a polymer.

The pressure-sensitive adhesive H was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape H.

[Comparative Example 3]
(Preparation of Adhesive I)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and Quinton G115 ₍ C5 series / _C9 manufactured by Nippon Zeon Co., Ltd.) as the tackifier resin (b1). Styrene petroleum resin, softening point 115 ° C.) 40 parts by mass, as adhesive-imparting resin (b2) Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C.) 40 parts by mass, aging Adhesion by mixing 1 part by mass of an inhibitor (tetrakis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) and dissolving it in 100 parts by mass of toluene as a solvent. Agent I was obtained.

The adhesive tape I was prepared by applying the pressure-sensitive adhesive I on a release paper with an applicator so that the thickness after drying was 300 μm and drying at 80 ° C. for 5 minutes.

[Comparative Example 4]
(Preparation of adhesive J)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), Styrene-isopregen block copolymer ratio of 60% by mass to the total amount of the composition a) 100 parts by mass, as a tackifier resin (b1) Quinton G115 ₍ C5 series / _C9 series petroleum manufactured by Nippon Zeon Co., Ltd.) Resin, softening point 115 ° C) 40 parts by mass, adhesive resin (b2) as Pencel D-160 (polymerized rosin ester resin manufactured by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C to 165 ° C) 10 parts by mass, antiaging agent (Tetraquis- [methylene-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) 1 part by mass of methane) is mixed and dissolved in 100 parts by mass of toluene as a solvent to make the pressure-sensitive adhesive J. Got

The pressure-sensitive adhesive J was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape J.

[Comparative Example 5]
(Preparation of adhesive K)
Styrene-isoprene block copolymer composition (A2) (mixture of styrene-isopregen block copolymer and styrene-isoprenetriblock copolymer, 24% by mass of structural unit derived from styrene represented by the above chemical formula (1), The ratio of the styrene-isopregen block copolymer to the total amount of the composition (A2) is 60% by mass) 100 parts by mass, and the pressure-imparting resin (b2) is Pencel D-160 (polymerized rosin ester manufactured by Arakawa Chemical Industry Co., Ltd.). Resin, softening point 150 ° C to 165 ° C) 75 parts by mass, anti-aging agent (tetrakis-3- (3'5'-di-t-butyl-4-hydroxyphenyl) propionate] methane) 1 part by mass. Adhesive K was obtained by mixing and dissolving in 100 parts by mass of toluene as a solvent.

The pressure-sensitive adhesive K was applied to a release paper with an applicator so that the thickness after drying was 300 μm, and dried at 80 ° C. for 5 minutes to prepare a pressure-sensitive adhesive tape K.

[Measuring method of T-shaped peel adhesive strength]
Polyethylene (PE) -based foam (Softlon S # 0502 manufactured by Sekisui Chemical Co., Ltd., apparent density 200 kg / m ³ , thickness 2.0 mm) is placed on both sides of the adhesive tape cut to a width of 20 mm and a length of 100 mm. After the bonding, the upper surface was reciprocated once with a 2 kg roller to crimp them, and the test piece was left in an environment of 60 ° C. for 24 hours to be sufficiently adhered to the PE foam to prepare a test piece.

In an environment of 23 ° C., one end of the adherend of the test piece is fixed to the lower chuck of the pulling device portion of the Tensilon tensile tester, and the other end of the adherend is fixed to the pulling device of the Tensilon tensile tester. The adhesive force (T-shaped peel adhesive force) was measured by fixing to the upper chuck of the portion and pulling the upper chuck at a speed of 50 mm / min.

[T-shaped peel judgment method]
The comprehensive judgment of the T-shaped peel measurement was as follows.
When the adhesive strength is 20N / 20mm or more and the PE-based foam breaks and peels off: 〇 When the adhesive strength is less than 20N / 20mm and the PE-based foam breaks and peels off: △
When peeling off at the interface between the adhesive layer and the PE-based foam: ×

[Evaluation method of holding power]
One of the adhesive surfaces of the adhesive tape is lined with a polyethylene terephthalate film having a thickness of 25 μm, cut to a width of 25 mm and a length of 100 mm, and then a clean and smooth surface stainless steel plate (at 23 ° C. and 50% RH atmosphere). Place it on the surface of No. 360 water-resistant polishing paper (hairline polishing treatment) so that the sticking area is 25 mm × 25 mm, and crimp them by reciprocating the upper surface once with a 2 kg roller, and 1 in an environment of 23 ° C. A test piece was prepared by leaving it for a while.

With the stainless steel plate constituting the test piece fixed, the time from when a load of 0.5 kg was applied to the adhesive tape in an environment of 40 ° C. until the adhesive tape fell from the stainless steel plate was measured. .. When the adhesive tape did not fall even after 24 hours or more, it was indicated as "> 24" in Tables 1 and 2.

The composition and evaluation results of the pressure-sensitive adhesive sheets of Examples and Comparative Examples are shown in the table below.

Claims (9)

It contains a styrene-isoprene block copolymer (A) and a tackifier resin (B).
The styrene-isoprene block copolymer (A) contains a styrene-isoprene block copolymer (a1) and a styrene-isoprene block copolymer (a2).
The content of the tackifier resin (B) is 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A).
The tackifier resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2).
An adhesive tape having an adhesive layer in which the blending ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2) is in the range of 2: 1 to 10: 1. The adhesive tape according to claim 1, wherein the content of the petroleum resin (b1) is 60% by mass or more in 100% by mass of the pressure-sensitive adhesive resin (B). Up to claim 1 or 2, wherein the petroleum resin (b1) is at least one selected from the group consisting of an aliphatic petroleum resin, an aromatic petroleum resin, and an aliphatic / aromatic copolymerized petroleum resin. The adhesive tape according to any one of the above. The adhesive tape according to any one of claims 1 to 3, wherein the rosin-based resin (b2) is a polymerized rosin-based resin. The adhesive tape according to any one of claims 1 to 4, wherein the structural unit represented by the following chemical formula (1) in the styrene-isoprene block copolymer (A) is 10 to 80% by mass.

The invention according to any one of claims 1 to 5, wherein the ratio of the styrene-isoprene block copolymer (a1) to the total amount of the styrene-isoprene block copolymer (A) is 10% by mass to 80% by mass. Adhesive tape. The adhesive tape according to any one of claims 1 to 6, wherein when the T-shaped peel adhesive force with respect to the polyolefin-based foam is measured by the following measuring method, the material of the polyolefin-based foam is broken and peeled off. ..
(Measuring method)
After adhering an adherend made of a polyolefin-based foam to both sides of the adhesive tape cut into a width of 20 mm and a length of 100 mm, the upper surface thereof is reciprocated once with a 2 kg roller and pressure-bonded under an environment of 60 ° C. One end of the adherend of the test piece was fixed to the lower chuck of the pulling device portion of the Tencilon tensile tester in an environment of 23 ° C. The T-shaped peel adhesive force is measured by fixing one end of the adherend to the upper chuck of the pulling device portion of the Tencilon tensile tester and pulling the upper chuck at a speed of 50 mm / min. The adhesive tape according to any one of claims 1 to 7, which has a T-shaped peel adhesive force of 15 N / 20 mm or more with respect to a polyolefin-based foam, which is measured by the following measuring method.
(Measuring method)
After adhering an adherend made of a polyolefin-based foam to both sides of the adhesive tape cut into a width of 20 mm and a length of 100 mm, the upper surface thereof is reciprocated once with a 2 kg roller and pressure-bonded under an environment of 60 ° C. One end of the adherend of the test piece was fixed to the lower chuck of the pulling device portion of the Tencilon tensile tester in an environment of 23 ° C. The T-shaped peel adhesive force is measured by fixing one end of the adherend to the upper chuck of the pulling device portion of the Tencilon tensile tester and pulling the upper chuck at a speed of 50 mm / min. It contains a styrene-isoprene block copolymer (A) and a tackifier resin (B).
The styrene-isoprene block copolymer (A) contains a styrene-isoprene block copolymer (a1) and a styrene-isoprene block copolymer (a2).
The content of the tackifier resin (B) is 75 parts by mass or more with respect to 100 parts by mass of the styrene-isoprene block copolymer (A).
The tackifier resin (B) contains a petroleum resin (b1) and a rosin-based resin (b2).
A pressure-sensitive adhesive having a compounding ratio (b1: b2) of the petroleum resin (b1) and the rosin-based resin (b2) in the range of 2: 1 to 10: 1.