Patent ID: 9328242
Filing Date: 2016-05-03
CPC Classification: C08G,C08K,C08L

Claim Text:
1. A polysiloxane composition comprising: (A) at least one type of organopolysiloxane that contains at least two unsaturated aliphatic hydrocarbon groups in the molecule, (B) at least one type of organohydrogenpolysiloxane that contains at least two silicon-bonded hydrogen atoms in the molecule, (C) a hydrosilylation reaction catalyst, and (D) inorganic particles in an amount of from 75 to 95 wt. % based on the total weight of the composition, said inorganic particles comprising 90% by weight or greater of silica and having a major axis to minor axis ratio of 1 to 1.2 and in which the proportion of particles having a diameter of 50 μm or greater is 5 wt. % or less of the total quantity of particles, wherein a weight fraction of the unsaturated aliphatic hydrocarbon groups in the organopolysiloxane (A) is from 1 to 7 wt. %, a compounding ratio of the inorganic particles (D) in the polysiloxane composition is from 70 to 85 vol. %, a value of [the weight fraction of the unsaturated aliphatic hydrocarbon groups in the organopolysiloxane (A)]×[the weight fraction of the silicon-bonded hydrogen atoms in the organohydrogenpolysiloxane (B)] is from 0.04 to 8, a viscosity of the polysiloxane composition at 25° C. is 500 Pa·s or less, and the polysiloxane composition provides a cured product having a coefficient of linear expansion at 30 to 300° C. of 80×10