Patent ID: 8039103

Claim:
A pressure-sensitive adhesive tape or sheet comprising a substrate having a pressure-sensitive adhesive layer on at least one side thereof, wherein the whole of the pressure-sensitive adhesive layer is formed of an aqueous dispersion pressure-sensitive adhesive composition containing, as a base polymer, (A) an acrylic polymer containing a (meth)acrylic acid C 4-12 alkyl ester as the major monomer component; wherein in a surface portion of the pressure-sensitive adhesive layer within the range of up to 3 nm inward from the outer face of the pressure-sensitive adhesive layer, (B) an anionic emulsifier containing a sulfur atom is contained in a proportion of from 0.1 to 3 parts by weight based on 100 parts by weight of the whole of the monomer components constituting the acrylic polymer (A) that forms the surface portion of the pressure-sensitive adhesive layer, wherein the concentration of the anionic emulsifier (B) containing a sulfur atom is increased inward from the surface; and wherein (C) at least one hydrophilic polymer selected from a homopolymer of polyethylene glycol, a homopolymer of polypropylene glycol, polyvinylpyrrolidone, polyvinyl alcohol, and poly-(meth)acrylic acid is contained in a proportion of from 0.5 to 15 parts by weight based on 100 parts by weight of non-volatile matters in the aqueous dispersion pressure-sensitive adhesive composition of the whole of the pressure-sensitive adhesive layer, wherein the hydrophilic polymer is added as an aqueous solution after the polymerization of the acrylic polymer.