Composition containing organopolysiloxane having polyoxyalkylene and perfluoroalkyl units

Claim 1

An antifoam silicone composition which comprises: (a) 100 parts by weight of an organopolysiloxane having polyoxyalkylene moieties and perfluoroalkyl groups and represented by the average unit formula ##STR21## in which R is a hydrogen atom or a monovalent hydrocarbon group having from 1 to 6 carbon atoms, G is polyoxyalkylene residue represented by the general formula ##STR22## A being a terminal group selected from the group consisting of a hydrogen atom, alkyl groups, acyl groups and isocyanato groups, R 1 being selected from the group consisting of n-propylene; isopropylene, n-butylene and isobutylene, R 2 being selected from the group consisting of ethylene, n-propylene, isopropylene, n-butylene and isobutylene, k and q each being a positive integer and m and n each being 0 or 1; Q is a group represented by the formula R f R 3 --, or R f R 3 --S--R 4 -- in which R f is a perfluoroalkyl group having from 1 to 18 carbon atoms, R 3 is a divalent hydrocarbon group having from 1 to 12 carbon atoms and R 4 is an ethylene group or a propylene group, with the proviso that Q does not contain more than 20 carbon atoms, and a, b and c are each a positive number with the proviso that a+b+c is in the range from 1.9 to 2.2 inclusive, and (b) from 0.1 to 200 parts by weight of a perfluoroalkyl-containing organopolysiloxane represented by the average unit formula ##STR23## in which R and Q each have the same meaning as defined above and d and e are each a positive number with the proviso that d+e is in the range from 1.9 to 2.2 inclusive.