Patent ID: 7173084

Claim:
A process for levelling a liquid resin system by adding a co-polymer as a levelling agent to the liquid resin system, said co-polymer comprising 0.5â€“4% by weight of the co-polymer of a fluorinated unit represented by formula I, wherein R 1 is a moiety selected from the group consisting of C n F 2n+1 â€”(CH 2 ) m â€”, AC n F 2n â€”(CH 2 ) m â€”, C n F 2n+1 â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”, AC n F 2n â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p , C n F 2n+1 â€”(CH 2 ) m â€”Xâ€”, AC n F 2n â€”(CH 2 ) m â€”Xâ€”, AC n F 2n â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”X or C n F 2n+1 â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”Xâ€”; wherein A is selected from the group consisting of H, Cl, Br, I, C 1-12 alkyls and OC 1-12 alkyls, wherein 4â‰¦nâ‰¦20, 0â‰¦mâ‰¦4 and 0â‰¦pâ‰¦20, wherein X is a spacer moiety selected from the group consisting of esters, amides, sulphoamides, mercapto groups, polyurethane groups and alkyl groups, wherein R 2 is selected from the group consisting of H, metal moieties, (alkyl)ammonium moieties, alkyl groups, C n F 2n+1 â€”(CH 2 ) m â€”, AC n F 2n â€”(CH 2 ) m â€”, C n F 2n+1 â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”, AC n F 2n â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p , C n F 2n+1 â€”(CH 2 ) m â€”Xâ€”, AC n F 2n â€”(CH 2 ) m â€”Xâ€”, AC n F 2n â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”X and C n F 2n+1 â€”(CH 2 ) m â€”(OCH 2 CHR 5 ) p â€”Xâ€”; wherein A is selected from the group consisting of H, Cl, Br, I, C 1-12 alkyls and OC 1-12 alkyls, wherein 4â‰¦nâ‰¦20, 0â‰¦mâ‰¦4 and 0â‰¦pâ‰¦20, wherein X is a spacer moiety selected from the group consisting of esters, amides, sulphoamides, mercapto groups, polyurethane groups and alkyl groups, wherein R 3 and R 4 are independently selected from the group consisting of H, alkyl-groups and phenyl-groups and wherein R 5 selected from the group consisting of H and methyl groups, said co-polymer further comprising alkyl(meth)acrylate units, and wherein 90â€“100% of the fluorinated units are mono-esters; and wherein 70â€“100% of the fluorinated units of the co-polymer are represented by formula I wherein n is 6â€“8.