Adhesive sheet

A method for preparing a release sheet comprising the steps of

• forming an undercoat layer by applying to one or both sides of a release sheet base material a coating composition comprising an acrylate or methacrylate copolymer resin, said resin having an emulsifier content of 2 to 10 wt. % based on the total amount of the monomers used to prepare said copolymer resin and
• forming a release agent layer on said undercoat layer, said acrylate or methacrylate copolymer resin comprising a mixture of a first copolymer and a second copolymer, said first and second copolymers comprising acrylate or methacrylate copolymers, said first copolymer comprising a copolymer prepared by emulsion polymerization of a first monomer mixture in the presence of a first emulsifier having a molecular weight of about 1,000 to about 10,000, said first emulsifier being used in an amount of 2 to 10 wt. % based on the total amount of said first monomer mixture, said copolymer having a glass transition temperature of -60 to 0.degree. C., said first monomer mixture comprising
• (a) about 1 to about 20 wt. % of a first ethylenically unsaturated carboxyl-containing monomer,
• (b) about 40 to about 90 wt. % of a first C.sub.4 -C.sub.18 alkyl ester monomer of acrylic or methacrylic acid and
• (c) 0 to about 40 wt. % of at least one first other monomer copolymerizable with said ethylenically unsaturated carboxyl containing monomer and said C.sub.4 -C.sub.18 alkyl ester of acrylic or methacrylic acid,
• said second copolymer comprising a copolymer prepared by emulsion polymerization of a second monomer mixture in the presence of a second emulsifier having a molecular weight of about 1,000 to about 10,000, said second emulsifier being used in an amount of about 2 to about 10 wt. % based on the total amount of said second monomer mixture, and said second copolymer having a glass transition temperature of 45 to 100.degree. C., said second monomer mixture comprising
• (d) about 1 to about 20 wt. % of a second ethylenically unsaturated carboxyl-containing monomer,
• (e) about 5 to about 40 wt. % of a second C.sub.4 -C.sub.18 alkyl ester monomer of acrylic or methacrylic acid, and
• (f) about 50 to about 90 wt. % of at least one second other monomer copolymerizable with said second ethylenically unsaturated carboxyl-containing monomer and said second C.sub.4 -C.sub.18 alkyl ester monomer of acrylic or methacrylic acid.