Patent ID: 8450224

Claim:
A water-dispersed pressure-sensitive adhesive composition comprising (a) as a base polymer thereof a water-dispersed acrylic copolymer (component L) with a glass transition temperature (Tg) in the range of −70° C. to −50° C., and (b) 10 to 40 parts by weight of a tackifying resin (component T) in relation to 100 parts by weight of the component L based on solid content, wherein the component L is an acrylic copolymer obtained by polymerization of a monomer starting material comprising: 60 wt % or more of an alkyl (meth)acrylate having a C 8-12 alkyl group, and 5 wt % or less of a radical polymerizable monomer having a carboxyl group (monomer b), wherein the monomer b comprises acrylic acid and methacrylic acid at an acrylic acid/methacrylic acid weight ratio of 0.3 to 4; and wherein, when a double-sided pressure-sensitive adhesive sheet is fabricated using the adhesive composition, the pressure-sensitive adhesive sheet satisfies all of the following properties: (A) an average adhesive strength on stainless steel of 11 N/20 mm or greater on either side; (B) an average adhesive strength on polypropylene of 8.5 N/20 mm or greater on either side; (C) a hold time in an 80° C. holding strength test of 1 hour or longer on either side; and (D) a gap height of an edge of a test piece in a curved surface adhesion test of 10 mm or less.