Curable organopolysiloxane composition

Claim 1

A curable organopolysiloxane composition comprising (A) 100 parts by weight of a mixture of (a) an organopolysiloxane with a viscosity at 25° C. of 0.02 to 1,000 Pa.s that contains at least 2 silicon-bonded alkoxy groups in each molecule and the monovalent organic groups bonded to the silicon atoms other than the alkoxy groups are monovalent hydrocarbon groups or monovalent halogenated hydrocarbon groups, and (b) an organopolysiloxane with a viscosity at 25° C. of 0.02 to 1,000 Pa.s that contains at least 2 silicon-bonded lower alkenyl groups in each molecule, (B) an organopolysiloxane that contains at least 2 silicon-bonded hydrogen atoms in each molecule, in a quantity that gives a value in the present composition of 0.3 to 5 moles of silicon-bonded hydrogen in this component to one mole of silicon-bonded lower alkenyl in component (b), (C) 0.1 to 20 parts by weight of an alkoxysilane with the general formula R 1 x Si(OR 2 ).sub.(4-x) where R 1 represents a monovalent hydrocarbon group, R 2 is alkyl or alkoxyalkyl, and x is 0, 1, or 2 or partial hydrolysis condensate thereof, (D) 0.01 to 20 parts by weight of an organozirconium compound or organoaluminum compound, and (E) a hydrosilylation reaction catalyst in a catalytic quantity.