Patent ID: 8088864

Claim:
A pressure-sensitive adhesive composition comprising an acrylic polymer (a), an acrylic oligomer (b), a silane coupling agent having an amino group, and a cross-linking agent, said acrylic polymer (a) containing, as a main monomer component, at least one of a (meth)acrylic acid alkyl ester containing an alkyl group having a number of carbons of from 4 to 12 and a (meth)acrylic acid alkoxyalkyl ester, and containing 1 to 10 parts by weight of a carboxyl group-containing monomer as a monomer component based on 100 parts by weight of the total monomer components constituting the acrylic polymer (a), the acrylic polymer (a) having a weight-average molecular weight of from 400,000 to 1,500,000; and said acrylic oligomer (b) containing a (meth)acrylic acid ester as a main monomer component, and containing 1 to 10 parts by weight of a carboxyl group-containing monomer as a monomer component based on 100 parts by weight of the total monomer components constituting the acrylic oligomer (b), the acrylic oligomer (b) having a weight-average molecular weight of 3,000 or more but less than 6,000, wherein the pressure-sensitive adhesive composition contains 10 to 35 parts by weight of the acrylic oligomer (b) and 0.01 part by weight or more but less than 1.0 part by weight of the silane coupling agent having an amino group, based on 100 parts by weight of the acrylic polymer (a).