Curable Silicone Composition, Cured Product Thereof, And Optical Semiconductor Device

摘要

The present invention relates to a curable silicone composition comprising: (A) a diorganopolysiloxane having at least two alkenyl groups in a molecule, (B) at least two types of resinous organopolysiloxanes having different mass average molecular weights, (C) an organopolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule, and (D) a hydrosilylation reaction catalyst. The curable silicone composition enables the production of an optical semiconductor device in which the marked viscosity elevation of the resulting composition can be inhibited, in which the fluidity and packing properties are outstanding and that has outstanding gas barrier properties when used as a sealant, and in which the device has outstanding initial optical output efficiency even when organopolysiloxane resin is blended in order to form cured product with moderate hardness and strength.

主权项

1. A curable silicone composition comprising:
(A) a diorganopolysiloxane having at least two alkenyl groups in a molecule and containing siloxane units represented by the formula: R12SiO2/2 (wherein each R1 independently represents an aryl group; (B) at least two types of resinous organopolysiloxanes having different mass average molecular weights based on standard polystyrene conversion gel permeation chromatography, and each comprising siloxane units represented by the formula: SiO4/2, siloxane units represented by the formula: R22R3SiO1/2 (wherein each R2 independently represents a monovalent hydrocarbon group lacking aliphatic unsaturated bonds and each R3 independently represents an alkenyl group, and siloxane units represented by the formula: R23SiO1/2 (wherein R2 has the same significance is as defined above, in an amount of 10 to 100 parts by mass per 100 parts by mass of component (A); (C) an organopolysiloxane having at least two silicon-bonded hydrogen atoms in a molecule, in an amount so that the amount of silicon-bonded hydrogen atoms in component (C) is from 0.1 to 10 mol per 1 mol of total alkenyl groups in components (A) and (B); and (D) a catalytic amount of hydrosilylation reaction catalyst.