Patent ID: 7789959

Claim:
A preservative-free aqueous coating composition having a pH of at least 10, comprising a) at least one strongly basic agent to set the pH, b) at least one emulsion of a copolymer derived from A1) vinyl esters of aliphatic saturated carboxylic acids having a chain length of C 1 -C 4 , A2) alpha-olefins having 2 to 8 carbon atoms, and A3) vinyl esters of aliphatic saturated carboxylic acids having a chain length of C 5 -C 18 , A4) ethylenically unsaturated monomers containing silane groups, wherein said ethylenically unsaturated monomers containing silane groups are selected from the group consisting of compounds of formula CH 2 ═CR 2 —(CH 2 ) 0-1 Si(CH 3 ) 0-1 (OR 1 ) 3-2 , compounds of formula CH 2 ═CR 2 CO 2 —(CH 2 ) 3 Si(CH 3 ) 0-1 (OR 1 ) 3-2 , and mixtures thereof, wherein R 1 is a branched or unbranched alkyl radical having 1 to 12 carbon atoms, wherein said branched or unbranched alkyl radical can optionally be interrupted by an ether group, and R 2 is H or CH 3 , and A5) optionally, further comonomers, the sum of components A1, A2, A3, A4, and optionally components A5 making 100% by weight, c) optionally, pigment and/or filler, and d) optionally, further additives.