Silicone coatings on air bags

Abstract

Air bags which are used for safety purposes to protect occupants of vehicles such as automobiles are described together with a process for coating air bags and air bag fabrics with silicone rubber compositions. In particular the invention relates to silicone rubber coatings which cure by hydrosilylation and an air bag coated with an elastomeric coating which is the cured product of a silicone composition comprising an organopolysiloxane (A) having aliphatically unsaturated hydrocarbon or hydrocarbonoxy substituents, an organosilicon crosslinker having at least 3 silicon-bonded hydrogen atoms, a catalyst able to promote the reaction of the aliphatically unsaturated hydrocarbon or hydrocarbonoxy substituents with Si—H groups and a reinforcing filler, wherein the organopolysiloxane (A) comprises a branched organopolysiloxane (A1) consisting of: (i) one or more Q units of the formula (SiO) and (ii) from 15 to 8000 D units of the formula RbSiOwhich units (i) and (ii) may be inter-linked in any appropriate combination, and (i{umlaut over (υ)}) M units of the formula RRSiOwherein each Rsubstituent is selected from the group consisting of an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having from 1 to 6 carbon atoms and an alkynyl group having from 1 to 6 carbon atoms, at least three Rsubstituents in the branched siloxane being alkenyl or alkynyl units, and each Rsubstituent is selected from the group consisting of an alkyl group having from 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an aryl group, an alkoxy group, an acrylate group and a methacrylate group.