Coating agents that are devoid of preservatives, method for their production and use thereof

1. 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.

2. The coating composition of claim 1 , wherein component A1) is vinyl acetate.

3. The coating composition of claim 1 , wherein component A2) is ethylene.

4. The coating composition of claim 1 , wherein component A3) is a vinyl ester of α-branched carboxylic acids having 9 to 11 carbon atoms in the acid radical.

5. The coating composition of claim 1 , wherein component A5) is present and is an ethylenically unsaturated carboxylic acid having one or two carboxyl groups and its salts, an ethylenically unsaturated sulfonic acid having one sulfonic acid group and its salts, and mixtures thereof.

6. The coating composition of claim 1 , wherein component a) is a water-soluble silicate.

7. The coating composition of claim 1 , wherein component a) is potassium waterglass.

8. The coating composition of claim 1 , wherein component a) is present in the coating composition in an amount up to 5% by weight, based on the total solids content.

9. The coating composition of claim 1 , wherein component b) comprises structural repeating units derived from the monomer groups A1, A2, A3, A4, and A5.

10. The coating composition of claim 1 , wherein component b) comprises at least one protective colloid, at least one emulsifier, or mixtures thereof.

11. The coating composition of claim 5 , wherein component A5) is selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, vinylsulfonic acid, and mixtures thereof.

12. The coating composition of claim 10 , wherein component b) comprises polyvinyl alcohol.

13. The coating composition of claim 2 , wherein component A2) is ethylene.

14. The coating composition of claim 13 , wherein component A3) is a vinyl ester of a-branched carboxylic acids having 9 to 11 carbon atoms in the acid radical.

15. The coating composition of claim 14 , wherein component A4) is a silane of formulae CH 2 ═CR 2 —(CH 2 ) 0-1 Si(CH 3 ) 0-1 (OR 1 ) 3-2 , 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 8 carbon atoms and R 2 is H or CH 3 .

16. The coating composition of claim 14 , wherein component A5) is present and is an ethylenically unsaturated carboxylic acid having one or two carboxyl groups and its salts, an ethylenically unsaturated sulfonic acid having one sulfonic acid group and its salts, and mixtures thereof.

17. The coating composition of claim 14 , wherein component a) is potassium waterglass.

18. The coating composition of claim 14 , wherein component a) is present in the coating composition in an amount up to 5% by weight, based on the total solids content.