Patent ID: 8193276

Claim:
A water and oil proofing composition comprising a fluorocopolymer comprising from 40 to 98 mass % of polymerized units (a′) based on the following monomer (a), from 1 to 50 mass % of polymerized units (b′) based on the following monomer (b) and from 1 to 10 mass % of polymerized units (c′) based on the following monomer (c): monomer (a): a compound represented by (Z—Y) n X, wherein Z is a C 1-6 perfluoroalkyl group or a monovalent group represented by C m F 2m+1 O(CFWCF 2 O) d CFK—, wherein m is an integer of from 1 to 6, d is an integer of from 1 to 4, and each of W and K which are independent of each other, is a fluorine atom or a trifluoromethyl group, Y is a single bond or a bivalent organic group containing no fluorine atom, n is 1 or 2, provided that when n is 1, X is —CR═CH 2 , —COOCR═CH 2 , —COOCR═CH 2 , —OCH 2 -φ-CR═CH 2 or —OCH═CH 2 , and when n is 2, X is —CH(—(CH 2 ) p CR═CH 2 )—, —CH(—(CH 2 ) p COOCR═CH 2 )—, —CH(—(CH 2 ) p OCOCR═CH 2 )— or —OCOCH═CHCOO—, R is a hydrogen atom, a methyl group or a halogen atom, φ is a phenylene group, p is an integer of from 0 to 4, and when n is 2, two (Z—Y) present in one molecule may be the same or different from each other; monomer (b): a compound represented by CH 2 ═CR 1 -G-(R 2 O) q —R 3 , wherein R 1 is a hydrogen atom or a methyl group, R 2 is a C 2-4 alkylene group, or a C 2-3 alkylene group having some or all of its hydrogen atoms substituted by hydroxyl groups, q is an integer of from 1 to 10, G is —COO(CH 2 ) r — or —COO(CH 2 ) t —NHCOO—, wherein r is an integer of from 0 to 4, and t is an integer of from 1 to 4, and R 3 is a hydrogen atom, a methyl group, an acryloyl group, a methacryloyl group or an allyl group; monomer (c): a compound represented by CH 2 ═C(COOH)-Q-COOH, wherein Q is a C 1-4 alkylene group, or a C 2-3 alkylene group having some or all of its hydrogen atoms substituted by hydroxyl groups, and an aqueous medium wherein the content of a volatile organic solvent in the aqueous medium is not more than 1 mass %, and in the polymerized units (c′), some or all of carboxyl groups form at least one salt selected from the group consisting of an alkali metal salt, an ammonium salt and an organic amine salt.