Patent ID: 8680223

Claim:
A water- and oil-repellent including, as an active ingredient, a fluorine-containing copolymer comprising as a copolymerization unit: (a) 5 to 40 wt. % of a perfluoroalkylalkyl acrylate represented by the general formula: C n F 2n+1 C m H 2m OCOCH═CH 2 wherein n represents an integer consisting of 4, 5, or 6; and m represents 1, 2, 3, or 4, (b) 35 to 60 wt. % of a perfluoroalkylalkyl methacrylate represented by the general formula: C n F 2n+1 C m H 2m OCOC(CH 3 )═CH 2 wherein n represents 4, 5, or 6; and m represents 1, 2, 3, or 4, (c) 5 to 40 wt. % of a fluorine-free polymerizable monomer, and (d) 0.5 to 40 wt. % of a cross-linkable group-containing polymerizable monomer, wherein the only fluorine polymerizable monomers in said fluorine-containing copolymer consist of (a) and (b).