Functionalized photoinitiators, macromers thereof, and the use thereof for contact lens

A contact lens, comprising:

• (a) an oligomer or polymer containing H-active groups, --OH and/or --NH-- bonded to the oligomer or polymer backbone, either via a bridge group selected from the group consisting of --(C.sub.1 -C.sub.4 alkylene-O)--, --(C.sub.2 -C.sub.10 alkylene-NH)-- and --C(O)--(CHOH).sub.r --CH.sub.2 --O-- where r is 0-4, or directly bonded, or containing H-active --NH-- groups bonded in the oligomer or polymer backbone, some or all of whose H atoms in the H-active groups have been substituted by radicals of formula IV:
• ##STR47## in which X is O;
• Y is O, NH or NR.sub.6 ;
• Y.sub.1 is O;
• Y.sub.2 is --O--, --O--(O)C--, --C(O)--O-- or --O--C(O)--O--;
• each n, independently of one another, is 0 or 1;
• R is H, C.sub.1 -C.sub.12 alkyl, C.sub.1 -C.sub.12 alkoxy or C.sub.1 -C.sub.12 alkyl-NH--;
• R.sub.1 and R.sub.2, independently of one another, are H, linear or branched C.sub.1 -C.sub.8 alkyl, C.sub.1 -C.sub.8 hydroxyalkyl or C.sub.6 -C.sub.10 aryl, or two groups R.sub.1 --(Y.sub.1).sub.n -- together (CH.sub.2).sub.x -- or the R.sub.1 --(Y.sub.1).sub.n -- and R.sub.2 --(Y.sub.1).sub.n -- groups together form a radical of the formula:
• ##STR48## R.sub.3 is a direct bond or linear or branched C.sub.1 -C.sub.8 alkylene, which is unsubstituted or substituted by --OH and/or is uninterrupted or interrupted by one or more --O--, --O--C(O)-- or --O--C(O)--O-- groups;
• R.sub.4 is branched C.sub.3 -C.sub.18 alkylene, C.sub.6 -C.sub.10 arylene, which is unsubstituted or substituted by by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, C.sub.7 -C.sub.18 aralkylene which is unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, C.sub.3 -C.sub.8 cycloalkylene which is substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, C.sub.3 -C.sub.8 cycloalkylene-C.sub.y H.sub.2y -- which is unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, or --C.sub.y H.sub.2y --C.sub.3 -C.sub.8 cycloalkylene-C.sub.y H.sub.2y -- which is unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy;
• R.sub.6 is linear or branched C.sub.1 -C.sub.6 alkyl;
• x is an integer from 3 to 5;
• y is an integer from 1 to 6;
• and
• R.sub.a and R.sub.b, independently of one another, are H, C.sub.1 -C.sub.8 alkyl, C.sub.3 -C.sub.8 cycloalkyl, benzyl or phenyl;
• with the provisos:
• that n in the --(Y.sub.1).sub.n --R.sub.1 groups is 0 if R.sub.2 is H,
• that at most two Y.sub.1 radicals in the --(Y.sub.1).sub.n -- groups in the formula I are O and n in the other --(Y.sub.1).sub.n -- groups is 0,
• that at most one Y.sub.1 in the --(Y.sub.1).sub.n -- groups in the formula Ia is O and n in the other --(Y.sub.1).sub.n -- group is 0,
• that R.sub.4 provides different reactivity to the two NCX groups, and
• that n in the --(Y.sub.2).sub.n -- group is 0 if R.sub.3 is a direct bond;
• and
• (b) a thin outer coating, on at least part of the oligomer or polymer surface, of a graft polymer formed by photopolymerization of a non-volatile or low-volatility olefin.