Patent ID: 8394887

Claim:
A surface treatment agent comprising (I) a fluorine-containing polymer comprising: (A) repeating units derived from an S-Sulfate monomer having an —S—SO 3 — group and a carbon-carbon double bond, and (B) repeating units derived from a fluorine-containing monomer having a fluoroalkyl group and carbon-carbon double bond, and (II) water and/or an organic solvent, wherein the amount of the monomer (A) is from 0.1 to 50 parts by weight, based on 100 parts by weight of the fluorine-containing monomer (B); the S-Sulfate monomer (A) is of the formula: H 2 C═CX-A-S—SO 3 —Z wherein X is a hydrogen atom, a methyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a CFX 1 X 2 group wherein X 1 and X 2 respectively represent a hydrogen atom, a fluorine atom or a chlorine atom, a cyano group, a linear or branched fluoroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted benzyl group, or a substituted or unsubstituted phenyl group; A is -Ph-Y— or —COO—Y—, wherein Ph is a phenylene group optionally having a substituent, Y is a direct bond, an C 1 -C 10 aliphatic group optionally having an oxygen atom, a C 6 -C 10 aromatic, cycloaliphatic or araliphatic group optionally having an oxygen atom, a —CH 2 CH 2 N(R 1 )SO 2 — group wherein R 1 is an alkyl group having 1 to 4 carbon atoms or a —CH 2 CH(OY 1 )CH 2 — group wherein Y 1 is a hydrogen atom or an acetyl group, and Z is a hydrogen atom or a metal atom; and the fluorine-containing monomer (B) is of the formula: CH 2 ═CX—COO—Y—Rf wherein X is a hydrogen atom, a methyl group, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a substituted or unsubstituted benzyl group, or a substituted or unsubstituted phenyl group; Y is a direct bond, an C 1 -C 10 aliphatic group optionally having an oxygen atom, a C 6 -C 10 aromatic, cycloaliphatic or araliphatic group optionally having an oxygen atom, a —CH 2 CH 2 N(R 1 )SO 2 — group wherein R 1 is an alkyl group having 1 to 4 carbon atoms, or a —CH 2 CH(OY 1 )CH 2 — group wherein Y 1 is a hydrogen atom or an acetyl group, and Rf is a linear or branched fluoroalkyl group having 1 to 21 carbon atoms, a linear or branched fluoroalkenyl group having 1 to 21 carbon atoms, or a fluoroether group having total number of 1 to 200 of at least one repeating unit selected from the group consisting of —C 3 F 6 O—, —C 2 F 4 O— and —CF 2 O—.