Sealing material for automotive fuel cell cells

Abstract

The objective is to provide a sealing material for automotive fuel cell cells that reduces the number of assembly steps for the separator of the fuel cell, and that exhibits excellent sealing performance not only in a normal temperature environment of about 25°C but also in a high-temperature environment (100°C or higher, for example, 120°C). [Solution] A sealing material for automotive fuel cell cells, comprising a resin layer and an adhesive layer, wherein the adhesive layer comprises an adhesive composition containing a copolymer (A) having (a) a polymer block of α-methylstyrene monomer and (b) a (co)polymer block of one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins, one or more olefin polymers (B) containing one or more aliphatic monoolefins and / or one or more aliphatic polyenes, wherein the content of block (c) exceeds 95% by mass and is 100% by mass or less, and one or more tackifiers (C).

Description

Technical Field

[0001] The present invention relates to a sealing material for cells of automotive fuel cells.

Background Art

[0002] In recent years, a solid polymer fuel cell has been developed as a fuel cell and is being increasingly popularized for automotive applications and the like. In a solid polymer fuel cell, a basic component called a membrane electrode assembly (MEA (Membrane Electrode Assembly)), which is formed by laminating a fuel electrode (negative electrode), a polymer membrane (electrolyte membrane), and an oxygen electrode (positive electrode) in this order and integrating them, is sandwiched from above and below by a separator (bipolar plate) with a supply flow path of reaction gas engraved thereon to form one basic unit (single cell). By stacking and connecting these single cells in series to form a cell stack (fuel cell stack), a high voltage can be obtained (see, for example, Patent Document 1).

[0003] In the above fuel cell stack, a sealing material such as a gasket is provided to prevent leakage or mixing of fuel gas, oxidation gas, or cooling water between the separator and the polymer membrane (electrolyte membrane).

[0004] Conventionally, as such a sealing material, a sealing material in which an olefin-based hot melt adhesive is applied to both sides of a resin material as a base material has been used (Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the conventional sealing material described above is a fusion-type sealing material, which requires multiple fusion processes to attach to the separator, resulting in the problem of time-consuming assembly to the separator.

[0007] Furthermore, when automotive fuel cells are used under continuous high loads, they may reach localized or temporary high temperatures (above 100°C, for example, 120°C). Therefore, there is a need for sealing materials that provide excellent sealing performance not only at ambient temperatures of around 25°C but also at high temperatures (above 100°C, for example, 120°C).

[0008] Therefore, the object of the present invention is to provide a sealing material for automotive fuel cell cells that can reduce the number of assembly steps for the separator of the fuel cell, and that exhibits excellent sealing performance not only in a normal temperature environment of about 25°C but also in a high-temperature environment (100°C or higher, for example, 120°C). [Means for solving the problem]

[0009] The above problems are solved as follows: In other words, the present invention (1) comprises a resin material layer and an adhesive layer laminated on both main surfaces of the resin material layer, The adhesive layer comprises an adhesive composition containing: (a) a polymer block of α-methylstyrene monomer; (b) a copolymer (A) having one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins (co)polymer blocks or partial or fully hydrogenated blocks thereof; (c) one or more olefin polymers (B) having one or more aliphatic monoolefins and / or one or more aliphatic polyenes (co)polymer blocks or partial or fully hydrogenated blocks thereof, wherein the content of block (c) exceeds 95% by mass and is 100% by mass or less based on monomers; and one or more tackifiers (C). This invention provides a sealing material for automotive fuel cell cells, characterized by the following features.

[0010] Furthermore, the present invention (2) provides a cell sealing material for an automotive fuel cell according to claim 1, characterized in that the content of (d) styrene or monomer polymer blocks having a styrene structure in the olefin polymer (B) is less than 5% by mass on a monomer basis.

[0011] Furthermore, the present invention (3) provides a sealing material for automotive fuel cell cells according to claim 1, characterized in that the ratio of the content of copolymer (A) to the total content of copolymer (A) and olefin polymer (B) ((copolymer (A) / (copolymer (A) + olefin polymer (B))) × 100) is 5 to 95% by mass.

[0012] Furthermore, the present invention (4) provides a sealing material for automotive fuel cell cells according to claim 1, characterized in that the resin material is selected from thermosetting resins, general-purpose resins such as polyethylene and polypropylene, engineering plastics and super engineering plastics. [Effects of the Invention]

[0013] According to the present invention, it is possible to reduce the number of assembly steps for the separator of the cell of an automotive fuel cell, and to provide a sealing material for automotive fuel cell cells that exhibits excellent sealing performance not only in a normal temperature environment of about 25°C but also in a high-temperature environment (100°C or higher, for example, 120°C). [Brief explanation of the drawing]

[0014] [Figure 1] This figure schematically shows a vertical cross-section of one embodiment of a sealing material for a cell in an automobile fuel cell according to the present invention. [Modes for carrying out the invention]

[0015] The sealing material for automotive fuel cell cells of the present invention is It comprises a resin material layer and adhesive layers laminated on both main surfaces of the resin material layer, The adhesive layer comprises a copolymer (A) having (a) a polymer block of an α-methylstyrene monomer and (b) a (co)polymer block of one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins or a partial or fully hydrogenated block thereof, and one or more olefin polymers (B) containing a (co)polymer block of one or more aliphatic monoolefins and / or one or more aliphatic polyenes or a partial or fully hydrogenated block thereof, wherein the content ratio of the block of (c) exceeds 95% by mass and is 100% by mass or less based on monomers, and one or more tackifiers (C). It is a sealing material for a cell of an automotive fuel cell, characterized in that. In this specification, "(co)polymerization" means "polymerization or copolymerization".

[0016] FIG. 1 is a schematic view of a vertical cross section in an exemplary form of a sealing material for a cell of an automotive fuel cell according to the present invention. In the exemplary form shown in FIG. 1, the sealing material 1 for a cell of an automotive fuel cell has a resin material layer r and adhesive layers s, s laminated and disposed on both main surfaces of the resin material layer r, respectively.

[0017] The sealing material for a cell of an automotive fuel cell of the present invention has a laminated structure having a resin material layer and adhesive layers laminated and disposed on both main surfaces of the resin material layer, respectively. Examples of the sealing material for a cell of an automotive fuel cell of the present invention include a laminate having a three-layer structure in which a resin material layer and two adhesive layers are laminated in the order of adhesive layer / resin material layer / adhesive layer.

[0018] The resin material layer of the sealing material for a cell of an automotive fuel cell according to the present invention is made of a resin material. That is, the resin material layer is a molded body in which the resin material is molded in a layer shape. Examples of the resin material include one or more selected from thermosetting resins, general-purpose resins such as polyethylene and polypropylene, engineering plastics, and super engineering plastics.

[0019] The resin material layer can contain a plasticizer, an antifoaming agent, a reinforcing material, etc., if necessary.

[0020] The thickness of the resin material layer is appropriately selected in consideration of the compression ratio and the like.

[0021] The sealing material for the cell of the fuel cell for automobiles of the present invention has adhesive layers laminated and disposed on both main surfaces of the resin material layer. Each of these adhesive layers is composed of an adhesive composition. That is, the adhesive layer is formed by the adhesive composition.

[0022] The adhesive composition for forming the adhesive layer contains at least a copolymer (A), an olefin polymer (B), and a tackifier (C).

[0023] The copolymer (A) is a copolymer having (a) a polymer block of an α-methylstyrene monomer and (b) a (co)polymer block of one or more aliphatic olefins and / or one or more aliphatic conjugated diolefins or a partial or fully hydrogenated block thereof. That is, in the copolymer (A), in the molecular chain of the copolymer, one or more block portions of (a) and one or more block portions of (b) are present.

[0024] The block of (a) is a polymer block of an α-methylstyrene monomer and is a block formed by the polymerization of α-methylstyrene (CH2=C(CH3)-C6H5). That is, the polymer block of (a) α-methylstyrene monomer is a portion formed by polymerizing using α-methylstyrene (CH2=C(CH3)-C6H5) as a monomer.

[0025] The block of (b) is (b1) a (co)polymer block of one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins, or (b2) a polymer block formed by polymerizing one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins, and is a block formed by hydrogenating a part or all of the double bonds after polymerization.

[0026] In other words, (b1) is a portion formed by polymerization using one type of aliphatic monoolefin as a monomer, a portion formed by copolymerization using two or more types of aliphatic monoolefins as monomers, a portion formed by polymerization using one type of aliphatic conjugated diolefin as a monomer, a portion formed by copolymerization using two or more types of aliphatic conjugated diolefins as monomers, or a portion formed by copolymerization using one or more types of aliphatic monoolefins and one or more types of aliphatic conjugated diolefins as monomers.

[0027] Furthermore, (b2) is a portion formed by polymerization using one type of aliphatic conjugated diolefin as a monomer, a portion formed by copolymerization using two or more types of aliphatic conjugated diolefins as monomers, or a portion formed by copolymerization using one or more types of aliphatic monoolefins and one or more types of aliphatic conjugated diolefins as monomers, and furthermore, a portion formed by hydrogenation of some or all of the double bonds after polymerization.

[0028] The aliphatic monoolefins related to block (b) are linear or branched aliphatic monoolefins having 2 or more carbon atoms, preferably 2 to 13. Examples of aliphatic monoolefins related to block (b) include ethylene, propylene, 1-butene, 2-butene, isobutylene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 1-hexene, 2-hexene, 3-hexene, 2-methyl-1-pentene, 2-methyl-2-pentene, 4-methyl-1-pentene, 4-methyl-2-pentene, n-heptene, isoheptene, n-octene, isooctene, n-nonene, isooctene, n-decene, isodecene, n-undecene, isoundecene, 6,10-dimethyl-1-undecene, etc.

[0029] The aliphatic conjugated diolefins related to the block in (b) are linear or branched aliphatic conjugated diolefins having 4 or more carbon atoms, preferably 4 to 15. Examples of aliphatic conjugated diolefins related to the block in (b) include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-cyclohexadiene, 1,3-heptadiene, 1,3-octadiene, 2-methyl-1,3-octadiene, myrcene, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene (common name: β-farnesene), etc.

[0030] As for the block in (b), a copolymer block of two or more monomers selected from ethylene, propylene, 1-butene, butadiene, isoprene, 6,10-dimethyl-1-undecene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or a partially or completely hydrogenated thereof block is preferred in that it has high adhesive strength at room temperature of about 25°C.

[0031] Such a block (b) is preferably, (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, (vii) Copolymer block of ethylene, propylene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, A copolymer block of ethylene, propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) isoprene and 6,10-dimethyl-1-undecene, or parts thereof, or fully hydrogenated blocks, Copolymer blocks of ethylene, propylene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof, or complete hydrogenated blocks, (viii) (Conjugated) butadiene polymer block, (ix) It is a polymer block of (conjugated) isoprene.

[0032] (b) Block is more preferably: (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, (vii) Copolymer block of ethylene, propylene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, A copolymer block of ethylene, propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) isoprene and 6,10-dimethyl-1-undecene, or parts thereof, or fully hydrogenated blocks, Copolymer blocks of ethylene, propylene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof, or complete hydrogenated blocks, That is the case.

[0033] (b) Block is more preferably: (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, A copolymer block of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or a partial or complete hydrogenated copolymer block thereof.

[0034] (b) Block is particularly preferably, (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A polymer block of (conjugated) butadiene, or a part thereof, or a complete hydrogenated block thereof.

[0035] The copolymer (A) is preferably a triblock copolymer consisting of (a) a polymer block of α-methylstyrene monomer - (b) a copolymer block or a portion thereof or a fully hydrogenated block of two or more monomers selected from ethylene, propylene, 1-butene, butadiene, isoprene, 6,10-dimethyl-1-undecene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene - (a) a polymer block of α-methylstyrene monomer.

[0036] The α-methylstyrene unit content of copolymer (A) is 10 to 40% by mass, preferably 15 to 40% by mass, and more preferably 20 to 35% by mass, based on the monomer. Having the α-methylstyrene unit content of copolymer (A) within this range suppresses the decrease in elastic modulus at high temperatures (100°C or higher, e.g., 120°C) and increases the adhesive strength at high temperatures (100°C or higher, e.g., 120°C).

[0037] The olefin polymer (B) is one or more olefin polymers (B) that include (c) a (co)polymer block or a portion thereof or a fully hydrogenated product block of one or more aliphatic monoolefins and / or one or more aliphatic polyenes, wherein the content of the block of (c) exceeds 95% by mass and is 100% by mass or less on a monomer basis. In the present invention, when the block of (c) in the olefin polymer (B) is 100% by mass on a monomer basis, the polymer of the olefin polymer (B) consists only of a (co)polymer or a portion thereof or a fully hydrogenated product of one or more aliphatic monoolefins and / or one or more aliphatic polyenes. Furthermore, in the present invention, if the block of (c) in the olefin polymer (B) exceeds 95% by mass and is less than 100% by mass on a monomer basis, the polymer molecular chain of the olefin polymer (B) contains one or more (c) copolymer blocks of one or more aliphatic monoolefins and / or one or more aliphatic polyenes, or a block of a part thereof or a fully hydrogenated form thereof, and one or more (copolymer blocks) other than the block of (c).

[0038] The block in (c) is (c1) a (co)polymerization block of one or more aliphatic monoolefins and / or one or more aliphatic polyenes, or (c2) a polymerization block formed by polymerization of one or more aliphatic monoolefins and / or one or more aliphatic polyenes, wherein some or all of the double bonds are hydrogenated after polymerization.

[0039] In other words, (c1) is a portion formed by polymerization using one type of aliphatic monoolefin as a monomer, a portion formed by copolymerization using two or more types of aliphatic monoolefins as monomers, a portion formed by polymerization using one type of aliphatic polyene as a monomer, a portion formed by copolymerization using two or more types of aliphatic polyenes as monomers, or a portion formed by copolymerization using one or more types of aliphatic monoolefins and one or more types of aliphatic polyenes as monomers.

[0040] Furthermore, (c2) is a portion formed by polymerization using one type of aliphatic polyene as a monomer, a portion formed by copolymerization using two or more types of aliphatic polyenes as monomers, or a portion formed by copolymerization using one or more types of aliphatic monoolefins and one or more types of aliphatic polyenes as monomers, and furthermore, a portion formed by hydrogenation of some or all of the double bonds after polymerization.

[0041] The aliphatic monoolefins related to block (c) are linear or branched aliphatic monoolefins having 2 or more carbon atoms, preferably 2 to 13. Examples of aliphatic monoolefins related to block (c) include ethylene, propylene, 1-butene, 2-butene, isobutylene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 3-methyl-1-butene, 1-hexene, 2-hexene, 3-hexene, 2-methyl-1-pentene, 2-methyl-2-pentene, 4-methyl-1-pentene, 4-methyl-2-pentene, n-heptene, isoheptene, n-octene, isooctene, n-nonene, isooctene, n-decene, isodecene, n-undecene, isoundecene, 6,10-dimethyl-1-undecene, and the like.

[0042] The aliphatic polyenes in block (c) are compounds having two or more double bonds. Examples of aliphatic polyenes in block (c) include linear or branched aliphatic conjugated diolefins having 4 or more carbon atoms, preferably 4 to 15; linear or branched aliphatic unconjugated diolefins having 4 or more carbon atoms, preferably 4 to 15; and aliphatic cyclic polyenes having 6 or more carbon atoms, preferably 6 to 18, more preferably 6 to 15. Examples of aliphatic conjugated diolefins related to the block in (c) include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 1,3-hexadiene, 1,3-cyclohexadiene, 1,3-heptadiene, 1,3-octadiene, 2-methyl-1,3-octadiene, myrcene, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, etc. An example of an aliphatic non-conjugated diolefin related to the block in (c) is 1,4-hexadiene. Examples of aliphatic cyclic polyenes related to the block in (c) include ethylidene norbornene, dicyclopentadiene, vinyl norbornene, etc.

[0043] As for the block in (c), copolymer blocks of two or more monomers selected from ethylene, propylene, 1-butene, isobutylene, butadiene, isoprene, 6,10-dimethyl-1-undecene, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, ethylidene norbornene, dichloropentadiene, and vinyl norbornene, or partially or completely hydrogenated thereof, are particularly preferred in that they have high adhesive strength at room temperature of about 25°C.

[0044] Such a block (c) is preferably, (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, (vii) Copolymer block of ethylene, propylene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, A copolymer block of ethylene, propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) isoprene and 6,10-dimethyl-1-undecene, or parts thereof, or fully hydrogenated blocks, Copolymer blocks of ethylene, propylene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof, or complete hydrogenated blocks, (viii) (Conjugated) butadiene polymer block, (ix) It is a polymer block of (conjugated) isoprene. (x) A copolymer block of ethylene, propylene, and ethylidene norbornene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, butene, and ethylidene norbornene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and vinylnorbornene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, butene, and vinylnorbornene, or a part thereof or a fully hydrogenated block, A copolymer block of ethylene, propylene, and dichloropentadiene, or a partial or complete hydrogenated product block thereof, This is a copolymer block of ethylene, propylene, and 1,4-hexadiene, or a partial or complete hydrogenated version thereof.

[0045] (c) Block is more preferably: (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, (vii) Copolymer block of ethylene, propylene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, A copolymer block of ethylene, propylene, (conjugated) isoprene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) isoprene and 6,10-dimethyl-1-undecene, or parts thereof, or fully hydrogenated blocks, Copolymer blocks of ethylene, propylene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, propylene, (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof, or complete hydrogenated blocks, That is the case.

[0046] (c) Block is more preferably: (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks, parts thereof, or complete hydrogenated blocks (iii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, (conjugated)butadiene, and (conjugated)isoprene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of (conjugated) butadiene and (conjugated) isoprene, or partial or complete hydrogenated product blocks thereof, (iv) Isobutylene polymer block (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, A copolymer block of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or a partial or complete hydrogenated copolymer block thereof.

[0047] (c) Block is particularly preferred, (i) Ethylene and 1-butene copolymer block, A copolymer block of ethylene and (conjugated) butadiene, or a partial or complete hydrogenated product block thereof, Copolymer blocks of 1-butene and (conjugated) butadiene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, and (conjugated) butadiene, or a partial or complete hydrogenated block thereof, (Conjugated) butadiene polymer blocks or parts thereof or complete hydrogenated blocks, (ii) Ethylene and propylene copolymer block, A copolymer block of ethylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of propylene and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, A copolymer block of ethylene, propylene, and (conjugated) isoprene, or a partial or complete hydrogenated product block thereof, (conjugated) isoprene polymer blocks or parts thereof or complete hydrogenated blocks, (iv) Isobutylene polymer block, (v) Copolymer block of ethylene and 6,10-dimethyl-1-undecene, Copolymer blocks of ethylene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or parts thereof or complete hydrogenated blocks, (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene polymer blocks, parts thereof, or complete hydrogenated blocks (vi) Copolymer block of ethylene, 1-butene, and 6,10-dimethyl-1-undecene, A copolymer block of ethylene, (conjugated) butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated product block thereof. Copolymer blocks of 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or partial or complete hydrogenated blocks thereof, A copolymer block of ethylene, 1-butene, (conjugated)butadiene, and 6,10-dimethyl-1-undecene, or a partial or complete hydrogenated block thereof, Copolymer blocks of (conjugated) butadiene and 6,10-dimethyl-1-undecene, or parts thereof, or complete hydrogenated blocks, Copolymer blocks of ethylene, 1-butene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of (conjugated) butadiene and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, Copolymer blocks of ethylene, 1-butene, (conjugated)butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or partial or complete hydrogenated blocks thereof, A copolymer block of (conjugated) butadiene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or a partial or complete hydrogenated copolymer block thereof.

[0048] In the olefin polymer (B), the content of (c) a (co)polymer block or a portion thereof or a fully hydrogenated block of one or more aliphatic monoolefins and / or one or more aliphatic polyenes is greater than 95% by mass and 100% by mass or less, preferably 96 to 100% by mass, based on monomers. The above range in the content of the block of (c) in the olefin polymer (B) results in high tackiness at room temperature of about 25°C, and also high tackiness at high temperatures (100°C or higher, for example, 120°C). In other words, it is possible to simultaneously impart flexibility at room temperature and suppress softening at high temperatures, resulting in high sealing performance (tackiness) at both room temperature and high temperatures.

[0049] In the olefin polymer (B), (co)polymer blocks other than the block in (c) may be present, provided that the amount is less than 5% by mass based on the monomer.

[0050] Examples of (co)polymer blocks other than block (c) relating to such olefin polymers (B) include (d) polymer blocks of styrene or monomers having a styrene structure.

[0051] Block (d) is a polymer block of styrene or monomers having a styrene structure, and is a block formed by polymerization of styrene (CH2=CH-C6H5) or monomers having a styrene structure. In other words, the polymer block of styrene or monomers having a styrene structure (d) is a part formed by polymerization using styrene (CH2=CH-C6H5) or monomers having a styrene structure as monomers. Note that the monomers having a styrene structure related to block (d) are compounds having a structure in which a "CH2=CH-" group is bonded to an aromatic ring, and the α-position of the vinyl group is bonded to a hydrogen atom, and the α-position does not have substituents such as alkyl groups. Therefore, the monomers having a styrene structure related to block (d) are different from compounds having a structure in which "CH2=CR- (R is a substituent such as an alkyl group)" is bonded to an aromatic ring, that is, compounds having a structure in which substituents such as alkyl groups are at the α-position of the vinyl group.

[0052] Examples of styrene or monomers having a styrene structure related to block (d) include styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-isopropylstyrene, 4-n-butylstyrene, 4-t-butylstyrene, 4-n-hexylstyrene, 4-cyclohexylstyrene, 4-octylstyrene, 4-dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, 4-vinylstyrene, 1,1-diphenylethylene, and the like.

[0053] Blocks of (d) include polymer blocks of styrene, and copolymer blocks of one or more monomers selected from styrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-isopropylstyrene, 4-n-butylstyrene, 4-t-butylstyrene, 4-n-hexylstyrene, 4-cyclohexylstyrene, 4-octylstyrene, 4-dodecylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 2,4,6-trimethylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, vinylanthracene, N,N-diethyl-4-aminoethylstyrene, vinylpyridine, 4-methoxystyrene, 4-vinylstyrene, and 1,1-diphenylethylene.

[0054] As an olefin polymer (B), a triblock copolymer consisting of (d) a polymer block of styrene or a monomer having a styrene structure - (c) a copolymer block or a part thereof or a fully hydrogenated block of one or more monomers selected from ethylene, propylene, 1-butene, isobutylene, butadiene, isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene - (d) a polymer block of styrene or a monomer having a styrene structure, diblock copolymer Any block copolymer is acceptable, but a diblock copolymer is more preferred, and the diblock copolymer may also contain a triblock copolymer, comprising (d) a polymer block of styrene or a monomer having a styrene structure - (c) a copolymer block of one or more monomers selected from ethylene, propylene, 1-butene, isobutylene, butadiene, isoprene, 6,10-dimethyl-1-undecene, and (6E)-7,11-dimethyl-3-methylidendodeca-1,6,10-triene, or a part thereof or a fully hydrogenated block.

[0055] In the olefin polymer (B), the content of block (d) is less than 5% by mass, preferably 0% by mass, based on the monomer. The above range for the content of block (d) in the olefin polymer (B) results in high tackiness at room temperature (around 25°C) and high tackiness at high temperatures (100°C or higher, e.g., 120°C). In other words, it is possible to simultaneously impart flexibility at room temperature and suppress softening at high temperatures, resulting in high sealing performance (tackiness) at both room temperature and high temperatures.

[0056] The olefin polymer (B) is preferably a copolymer of one or more α-olefins selected from ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene, or a copolymer of one or more α-olefins selected from ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene and an aliphatic polyene selected from ethylidene norbornene, dicyclopentadiene, hexadiene, vinyl norbornene, butadiene and isoprene.

[0057] The olefin polymer (B) is preferably a diene rubber selected from butyl rubber, natural rubber, isoprene rubber, butadiene rubber, and styrene-butadiene rubber, or a partially or fully hydrogenated diene rubber thereof.

[0058] The tackifier (C) enhances the tackiness of the adhesive layer and includes, for example, phenol resins, terpene resins, rosin resins, hydrogenated rosin resins, coumarone resins, terpene phenol resins, hydrogenated terpene phenol resins, aromatic hydrocarbon resins, and aliphatic hydrocarbon resins. More specifically, the tackifier (C) can be a terpene resin, a terpene phenol resin, a hydrogenated terpene resin, a hydrogenated terpene phenol resin, aromatic hydrocarbon resin, or aliphatic hydrocarbon resin. Preferably, the tackifier (C) is one or more selected from terpene phenol resins, hydrogenated terpene phenol resins, phenol resins, xylene resins, and rosin resins.

[0059] The softening point of the tackifier (C) is preferably 80 to 180°C, more preferably 100 to 170°C. The hydroxyl value of the tackifier (C) is preferably 5 to 200 mg KOH / g, more preferably 10 to 120 mg KOH / g.

[0060] In the adhesive composition of the present invention, the ratio of the content of copolymer (A) to the total content of copolymer (A) and olefin polymer (B) ((copolymer (A) / (copolymer (A) + olefin polymer (B))) × 100) is 5 to 95% by mass, preferably 10 to 95% by mass, more preferably 25 to 95% by mass, and more preferably 40 to 95% by mass. By having the ratio of the content of copolymer (A) to the total content of copolymer (A) and olefin polymer (B) within the above range, it is possible to achieve both high tackiness at high temperatures (100°C or higher, for example 120°C) and high tackiness at room temperature of about 25°C.

[0061] In the adhesive composition of the present invention, the ratio of the content of tackifier (C) to the total content of copolymer (A) and olefin polymer (B) ((tackifier (C) / (copolymer (A) + olefin polymer (B))) × 100) is 5 to 150% by mass, preferably 10 to 120% by mass, and more preferably 30 to 90% by mass. By having the ratio of the content of tackifier (C) to the total content of copolymer (A) and olefin polymer (B) within the above range, it is possible to achieve both high tackiness at high temperatures (100°C or higher, for example, 120°C) and high tackiness at room temperature of about 25°C.

[0062] The adhesive composition of the present invention may contain an antioxidant (D) in addition to the copolymer (A), the olefin polymer (B), and the tackifier (C). Examples of antioxidants (D) include amine-based, phenol-based, benzimidazole-based, phosphoric acid-based, and organic thioacid-based antioxidants.

[0063] When the adhesive composition of the present invention contains an antioxidant (D), the ratio of the antioxidant (D) content to the total content of copolymer (A) and olefin polymer (B) ((antioxidant (D) / (copolymer (A) + olefin polymer (B))) × 100) is 0.10 to 1.0% by mass, preferably 0.15 to 0.75% by mass, and more preferably 0.25 to 0.50% by mass. By having the ratio of the antioxidant (D) content to the total content of copolymer (A) and olefin polymer (B) within the above range, it is possible to suppress the decrease in adhesive strength caused by deterioration due to heat or light.

[0064] Furthermore, in addition to the copolymer (A), olefin polymer (B), and tackifier (C), the adhesive composition of the present invention may contain various additives used in the adhesive composition as needed, within a range that does not impair the effects of the present invention.

[0065] The adhesive composition of the present invention may contain a leveling agent (surfactant) (E) as an additive. Examples of leveling agents (surfactants) (E) include: silicone-based leveling agents such as polyester-modified silicone, polyether-modified silicone, polyether-polyester-modified silicone, silicone-modified (meth)acrylic resin, carbinol-modified silicone, amino-modified silicone, polydimethylsiloxane modified with carboxyl, ether, epoxy, etc., alkyl-modified silicone, alkyl-aralkyl-modified silicone, higher fatty acid ester-modified silicone, phenyl-modified silicone, carboxyl-modified silicone, epoxy-modified silicone, and fluorine-modified silicone; straight silicones such as polydimethylsiloxane, polyphenylsiloxane, polymethylphenylsiloxane, and polymethylhydrodienesiloxane; acrylic polymers, and silicone-modified acrylics. Examples of leveling agents include acrylic polymers such as yl polymers, fluorine-modified acrylic polymers, (meth)acrylic copolymers, and polyether-modified (meth)acrylic compounds; fluorine-based leveling agents such as perfluoroalkenyl carboxylates, perfluoroalkenyl sulfonates, perfluoroalkenyl phosphates, perfluoroalkyl polyoxyethylene ethers, perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, and perfluoroalkyl phosphates; vinyl polymers such as vinyl ether polymers; acetylene glycol-based leveling agents; and olefin polymers such as low molecular weight polyethylene, low molecular weight polypropylene, and modified olefin polymers such as ethylene-(meth)acrylic copolymers and acid-modified polyolefins. Other examples of leveling agents (surfactants) include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, fluorine-based surfactants, alkoxylated surfactants, hyperbranched polyethers, sulfosuccinates, tetramethyldecanediols, and alkoxyl-modified tetramethyldecanediols.

[0066] The adhesive composition of the present invention is obtained by mixing a copolymer (A), an olefin polymer (B), and a tackifier (C), along with an antioxidant (D) and a leveling agent (E) as needed, in a solvent, then mixing, stirring, or kneading using a stirrer, and then applying the mixture to an object to which an adhesive layer is to be formed, followed by heating and removing the solvent.

[0067] The solvent is not particularly limited and includes aliphatic hydrocarbons, aromatic hydrocarbons, ketones, esters, ethers, and alcohols, with aromatic hydrocarbons being preferred. The amount of solvent used is appropriately selected depending on the application, coating method, and coating thickness.

[0068] Copolymer (A) has a high elastic modulus at high temperatures above 100°C, for example, 120°C, and when combined with tackifier (C), it exhibits excellent tackiness at high temperatures. Olefin polymer (B) is flexible at room temperature of about 25°C, and when combined with tackifier (C), it exhibits excellent tackiness at room temperature of about 25°C. Therefore, the adhesive composition of the present invention, by containing (A), (B), and (C), becomes an adhesive composition with excellent tackiness over a wide temperature range.

[0069] Styrene-based block copolymers, such as poly(styrene-butadiene-styrene), are known as thermoplastic elastomers. Polystyrene blocks are called hard segments and are glassy at room temperature, while polybutadiene blocks are called soft segments and are rubbery at room temperature. Styrene-based thermoplastic elastomers exhibit rubber elasticity at room temperature because the hard segments act as crosslinking points. However, because the glass transition temperature of polystyrene is around 100°C, it loses its rubber elasticity and its modulus decreases at temperatures above 100°C. On the other hand, poly-α-methylstyrene contained in copolymer (A) has a higher glass transition temperature than polystyrene, and copolymer (A) does not easily lose its modulus at temperatures above 100°C. Therefore, the adhesive composition of the present invention, by using copolymer (A), becomes an adhesive composition with excellent tackiness at high temperatures (above 100°C, for example, 120°C).

[0070] On the other hand, if copolymer (A) is used without being combined with (B), the elastic modulus at room temperature of around 25°C becomes high, and the tackiness decreases.

[0071] Therefore, in the adhesive composition of the present invention, the ratio of the content of copolymer (A) to the total content of copolymer (A) and olefin polymer (B) ((copolymer (A) / (copolymer (A) + olefin polymer (B))) × 100) is 5 to 95% by mass, preferably 10 to 95% by mass, preferably 25 to 95% by mass, and more preferably 40 to 95% by mass, so that flexibility is maintained even at room temperature of about 25°C. Thus, the adhesive composition of the present invention, by using olefin polymer (B), becomes an adhesive composition with excellent tackiness at room temperature of about 25°C. However, if olefin polymer (B) is used without being combined with (A), the tackiness at temperatures above 100°C is almost lost.

[0072] As described above, the present invention provides an adhesive composition with excellent adhesiveness over a wide temperature range by combining a copolymer (A) with excellent adhesiveness at high temperatures, a copolymer (B) with excellent adhesiveness at low temperatures, and a tackifier (C).

[0073] The adhesive composition of the present invention may contain one or more copolymers (F) selected from polyphenylene ether copolymers, styrene-maleic anhydride copolymers, styrene-N-phenylmaleimide copolymers, and styrene-N-phenylmaleimide copolymer-maleic anhydride copolymers, wherein the copolymer has a glass transition temperature of 140°C or higher.

[0074] In the adhesive composition of the present invention, the content of copolymer (F) is 0 to 50% by mass, preferably 0 to 30% by mass, and more preferably 0 to 20% by mass, relative to copolymer (A).

[0075] The thickness of the adhesive layer is selected appropriately, taking into consideration clearance, compressibility, etc.

[0076] The cell sealing material for automotive fuel cells of the present invention is a sealing material that is placed inside a fuel cell mounted in an automobile and seals the various components of the fuel cell. The assembly process of a fuel cell varies, but conventional sealing materials require multiple assembly steps. In such cases, the cell sealing material is placed between separators after being joined to the MEA, or the MEA to which the cell sealing material is joined is alternately stacked with bipolar plates to which two separators are joined. However, with conventional sealing materials, multiple assembly steps are required. With the cell sealing material for automotive fuel cells of the present invention, assembly can be completed in a single, short-duration press. Therefore, by using the cell sealing material for automotive fuel cells of the present invention, the number of assembly steps can be reduced.

[0077] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited in any way by the following examples. [Examples]

[0078] In this invention, the sealing performance of the sealing material depends on the peel strength of the adhesive layer. Therefore, in the following examples and comparative examples, the sealing performance of the sealing material was evaluated by measuring the peel strength of the adhesive layer.

[0079] (Examples and Comparative Examples) <Preparation of adhesive solution> 280g of copolymer A (listed in Tables 1 and 2) and 520g of solvent were weighed into a 1L pail and stirred at 250-300rpm for at least 4 hours using a three-one motor to obtain a 35% solution (Solution A). A 35% solution (Solution B) was prepared in the same manner for copolymer B (B1-B5) (listed in Table 1). 140g of tackifier C (C1, C2) (listed in Table 1) and 260g of solvent were weighed into a polypropylene container with a lid, shaken to dissolve, and obtained a 35% solution (Solution C). Solutions A, B, and C were mixed together to achieve the mixing ratios and concentrations shown in Table 1, and the mixture was stirred at 500 rpm for 1 to 5 minutes using a three-one motor to prepare the adhesive solution. The concentration of the adhesive solution was adjusted by adding solvent as needed to maintain a concentration in the range of 30-35%.

[0080] <Production of Adhesive Film> The resin film was cut into pieces with a length of 400 mm and a width of 150 mm. At this time, the length direction was set as up and down, and the width direction was set as left and right. The resin film was fixed on a coating table, and an adhesive solution was coated using an applicator. The coated film was placed in a high-temperature constant-temperature machine to sufficiently dry the solvent. Coating and drying were also performed on the back surface of the resin film in the same process to obtain a double-sided adhesive film. The thickness of the portion 50 mm from the left and right ends of the adhesive film was measured with a micrometer as the adhesive thickness. The material of the resin film was selected from polyethylene terephthalate, polyethylene naphthalate, polyvinyl chloride, polystyrene, syndiotactic polystyrene, and polyimide, and surface treatment may be performed as necessary.

[0081] <Cutting of Adhesive Film for Peel Test> The adhesive film was cut 20 mm from the left and right ends and 40 mm from the upper and lower ends to obtain a film with a length of 320 mm and a width of 110 mm. This film was cut into pieces with a length of 35 mm and a width of 15 mm to obtain an adhesive film for peel test.

[0082] <Pressing of Adhesive Film for Peel Test> The adhesive film for peel test and the adherend (stainless steel plate) were pressed together. The adherend cut into pieces with a length of 70 mm and a width of 15 mm was washed with ethanol. Then, the lower ends of the adherend and the adhesive film for peel test were aligned, and the adherend was bonded to both sides of the adhesive film so that no air entered. Using an air press machine, a pressing treatment (10 kgf / cm 2 × 15 s: 70 °C) was performed to obtain a sample for peel test.

[0083] <T-Peel Test> A universal testing machine (Shimadzu Corporation, Autograph AGS-500NX) was used for the T-shaped peel test to measure adhesive strength. A jig with a chuck for tensile testing was attached to the testing machine, with a chuck distance of 50 mm. The workpiece was bent into a T-shape, held in place by the chucks, and the crosshead was raised at a speed of 50 mm / min to peel off the adhesive film in a T-shape. The test was performed at temperatures of 25°C, 100°C, and 120°C. When performing the test at temperatures above 100°C, the peel test was conducted while heating in a constant temperature bath. The peel strength [N / mm] was measured by dividing the test force [N] in the peel test by the width of 15 mm. For each measurement result, the relative value was calculated with the peel strength of Comparative Example 2 at 25°C set to "1.00". The results are shown in Tables 1 and 2.

[0084] [Table 1]

[0085] [Table 2]

[0086] A1: Hydrogenated α-methylstyrene-butadiene block copolymer, α-methylstyrene unit content (monomer basis): 29% by mass B1: Ethylene-propylene-diene copolymer (EPDM), (d) Block content: 0% by mass B2: Ethylene-butene-diene copolymer (EBDM), (d) Block content: 0% by mass B3: Ethylene-propylene copolymer, (d) Block content: 0% by mass β1: Hydrogenated styrene-isobutylene block copolymer, (d) Block content: 15% by mass based on styrene monomer β2: Hydrogenated styrene-butadiene block copolymer, (d) Block content: 20% by mass based on styrene monomer β3: Hydrogenated styrene-isoprene block copolymer, (d) Block content: 13% by mass based on styrene monomer C1: Terpene phenol resin C2: Terpene phenol resin C3: Hydrogenated terpene phenol resin

[0087] In Examples 1 to 9, the relative peel strength was 2.50 or higher at all temperatures (25°C, 100°C, and 120°C), compared to Comparative Example 2 at 25°C, where the peel strength was set to "1.00". On the other hand, in Comparative Examples 1, 2, 5, 7, and 10, the relative value of the peel strength at 25°C was less than 2.50 when the peel strength of Comparative Example 2 at 25°C was set to "1.00". In Comparative Examples 3 and 4, the relative value of the peel strength at 100°C was less than 2.50 when the peel strength of Comparative Example 2 at 25°C was set to "1.00". In Comparative Examples 3, 4, 5, 6, 8, 9, 11, 12, and 13, the relative value of the peel strength at 120°C was less than 2.50 when the peel strength of Comparative Example 2 at 25°C was set to "1.00".

[0088] Based on these results, the adhesive layers of Examples 1 to 9 exhibit high peel strength and excellent adhesion in all environments of 25°C, 100°C, and 120°C. Therefore, it is presumed that the sealing materials having the adhesive layers of Examples 1 to 9 will exhibit excellent sealing performance in both 25°C environments and high-temperature environments of 100°C and 120°C. [Industrial applicability]

[0089] According to the present invention, it is possible to reduce the number of assembly steps for the separator of the cell of an automotive fuel cell, and to provide a novel sealing material for automotive fuel cell cells that exhibits excellent sealing performance not only in a normal temperature environment of about 25°C but also in a high-temperature environment (100°C or higher, for example, 120°C). [Explanation of Symbols]

[0090] 1. Sealing material for automotive fuel cell cells r Resin material layer s Adhesive layer

Claims

1. It comprises a resin material layer and adhesive layers laminated on both main surfaces of the resin material layer, The adhesive layer comprises an adhesive composition containing: (a) a polymer block of α-methylstyrene monomer; (b) a copolymer (A) having one or more aliphatic monoolefins and / or one or more aliphatic conjugated diolefins (co)polymer blocks or partial or fully hydrogenated blocks thereof; (c) one or more olefin polymers (B) having one or more aliphatic monoolefins and / or one or more aliphatic polyenes (co)polymer blocks or partial or fully hydrogenated blocks thereof, wherein the content of block (c) exceeds 95% by mass and is 100% by mass or less based on monomers; and one or more tackifiers (C). A sealing material for automotive fuel cell cells, characterized by the following features.

2. The sealing material for automotive fuel cell cells according to claim 1, characterized in that the content of (d) polymer blocks of styrene or monomers having a styrene structure in the olefin polymer (B) is less than 5% by mass on a monomer basis.

3. The sealing material for automotive fuel cell cells according to claim 1, characterized in that the ratio of the content of copolymer (A) to the total content of copolymer (A) and olefin polymer (B) ((copolymer (A) / (copolymer (A) + olefin polymer (B))) × 100) is 5 to 95% by mass.

4. The sealing material for automotive fuel cell cells according to claim 1, characterized in that the resin material is selected from thermosetting resins, general-purpose resins such as polyethylene and polypropylene, engineering plastics and super engineering plastics.

Images