Silicone-compatible photoinitiators, and photosensitive mixtures

Abstract

Compounds of the general formula I: (SIL--X--).sub.m IN (I), in which SIL is a radical of the formula Si(R.sup.1)(R.sup.2)(R.sup.3), where R.sup.1 is an alkyl, haloalkyl or alkoxy radical of 1 to 8 carbon atoms, an alkenyl radical, an alkenyloxy or acyloxy radical of 2 to 8 carbon atoms, an aryl or aryloxy radical of 6 to 10 carbon atoms, or a dialkyl-, diaryl- or alkylaryl-methyleneaminooxy radical having C.sub.1 -C.sub.4 -alkyl or C.sub.6 -aryl groups; and R.sup.2 and R.sup.3 are identical or different radicals with the meaning of R.sup.1 or X--IN; X is a group C.sub.n H.sub.2n ; IN is the radical of a compound which is active as a photoinitiator or photosensitizer and which has at least one carbonyl group located on an aromatic nucleus; m is a number from 1 to 4; and n is a number from 2 to 12, or of the formula II: Si.sub.o O.sub.o-1 (--X--IN).sub.p R.sup.4.sub.2o+2-p (II), in which R.sup.4 is a radical with the meaning of R.sup.1, and two or more radicals R.sup.4 may be the same as or different from one another; o is a number from 2 to 20,000; and p is a number from 1 to o, and the symbols X and IN are as defined above, the group X being attached to an aromatic carbon atom which is positioned ortho to the carbonyl group of IN. The compounds are prepared by reacting a compound IN--H with a compound SIL--X' or a compound Si.sub.o O.sub.o-1 (--X').sub.p R.sup.4.sub.2o+2-p in the presence of a ruthenium compound. They are suitable as radical-forming photoinitiators or as photosensitizers in silicone-containing photopolymerizable mixtures, in particular for the production of waterless-printing planographic printing plates.