Adhesive composition, adhesive, and adhesive sheet

Abstract

The present invention provides an adhesive composition containing an acrylic resin that exhibits excellent adhesive strength after exposure to high temperature and high humidity conditions, and low elasticity at low temperatures. [Solution] An adhesive composition containing an acrylic resin (A), wherein the acrylic resin (A) has structural units derived from an alkoxysilyl group-containing copolymerizable monomer (a1).

Claims

[Claim 1] An adhesive composition containing an acrylic resin (A), The acrylic resin (A) is an adhesive composition having structural units derived from an alkoxysilyl group-containing copolymerizable monomer (a1). [Claim 2] The adhesive composition according to claim 1, wherein the alkoxysilyl group-containing copolymerizable monomer (a1) is a monomer represented by formula 1. X-(L)-SiR １ R ２ R ３ (Equation 1) (X is a polymerizable functional group, L represents an alkanediyl group having 1 to 10 carbon atoms, and -CH contained in the alkanediyl group ２ - may be substituted with -O-, -S-, -COO-, and when having a plurality of -O-, -S-, -COO-, they are not adjacent to each other. R １ , R ２ , and R ３ are each independently an alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a phenyl group bonded to Si, and at least one of R １ , R ２ , and R ３ is an alkoxy group having 1 to 10 carbon atoms.) [Claim 3] The alkoxysilyl group-containing copolymerizable monomer (a1) is 3-acryloxypropyltrimethoxysilane, 3-acryloxypropylmethyldimethoxysilane, 3-acryloxypropyltriethoxysilane, 3-acryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 8-acrylo The adhesive composition according to claim 1 or 2, wherein the adhesive is at least one selected from the group consisting of xyoctyltrimethoxysilane, 8-acryloxyoctylmethyldimethoxysilane, 8-acryloxyoctyltriethoxysilane, 8-acryloxyoctylmethyldiethoxysilane, 8-methacryloxyoctyltrimethoxysilane, 8-methacryloxyoctylmethyldimethoxysilane, 8-methacryloxyoctyltriethoxysilane, and 8-methacryloxyoctylmethyldiethoxysilane. [Claim 4] The adhesive composition according to claim 1 or 2, wherein the content of structural units derived from the alkoxysilyl group-containing copolymerizable monomer (a1) relative to the total structural units constituting the acrylic resin (A) is 0.1 to 10% by mass. [Claim 5] The adhesive composition according to claim 1 or 2, wherein the weight-average molecular weight of the acrylic resin (A) is 100,000 to 2,000,000. [Claim 6] The adhesive composition according to claim 1 or 2, further containing a crosslinking agent (B). [Claim 7] The adhesive composition according to claim 1 or 2, further containing a photopolymerization initiator (C). [Claim 8] The adhesive composition according to claim 7, wherein the photopolymerization initiator (C) contains a hydrogen abstraction type photopolymerization initiator (c1) and / or an intramolecular cleavage type photopolymerization initiator (c2). [Claim 9] An adhesive comprising the adhesive composition according to claim 1 or 2, which is crosslinked. [Claim 10] The adhesive according to claim 9, wherein the glass transition temperature based on dynamic viscoelasticity when an adhesive layer is formed from the adhesive is -35°C or lower. [Claim 11] An adhesive sheet having an adhesive layer made of the adhesive described in claim 9. [Claim 12] The adhesive sheet according to claim 11, wherein the adhesive layer hardens in multiple stages.

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