lent hydrocarbon group having no aliphatic unsaturation and n is a positive integer, and 30 to 1% by weight of an organopolysiloxane with a resin structure comprising SiO2 units, (CH2 ???CH)(R')2 SiO0.5 units and (R')3 SiO0.5 units, where R' is a methyl or phenyl group, (b) an organohydrogenpolysiloxane or a mixture of organohydrogenpolysiloxanes having at least two hydrogen atoms bonded directly