Patent ID: 7939614

Claim:
A silicon containing curing composition comprising: at least one silicon containing polymer selected from the group consisting of: component (A) and component (B); and component (D) a catalyst, wherein, said composition is applicable to the electrical and electronic field as a sealing compound; component (A) is a silicon containing polymer, which comprises: at least one kind of a reactive group A′ selected from the group consisting of Si—R 1 , Si—O—R 2 , and Si—R 3 —OCOC(R 4 )═CH 2 , wherein R 1 and R 2 each represent an alkenyl group having 2 to 20 carbon atoms which may contain an alkylene group and/or an arylene group, R 3 represents an alkylene group having 1 to 9 carbon atoms and/or an arylene group, and R 4 represents hydrogen or a methyl group, an Si—O—Si bridge structure formed from at least one site thereof, and 20% by weight or less of a component whose weight average molecular weight is 1000 or less; component (A) is obtained by reacting silicon containing polymer precursors with each other, one of said silicon containing polymer precursors is a linear polysiloxane compound, and said silicon containing polymer precursors are obtained by a sol gel process using: an alkoxysilane and/or chlorosilane having a reactive group A′, and/or an alkoxysilane and/or chlorosilane having no reactive group A′; component (B) is a silicon containing polymer, which comprises: an Si—H group, an Si—O—Si bridge structure formed from at least one site thereof, and containing 20% by weight or less of a component whose weight average molecular weight is 1000 or less, provided that said Si—H group is introduced into the polymer, which is formed by hydrolyzing and condensing an alkoxysilane and/or a chlorosilane, each having no Si—H group, using a reactive functional group Si—OH and/or a reactive functional group Si—Cl; component (D) is a platinum-based catalyst; the total aryl group and arylene group content of the total silicon containing polymers as components (A) and (B) is 1% to 25% by weight; and the components (A) and (B) each have a weight average molecular weight of 5,000 to 1,000,000.