Thermally conductive silicone compositions and their cured products

Abstract

This invention provides a thermally conductive silicone composition that can be compressed to a thickness that provides sufficient heat dissipation performance even when both a material flattening step and a heat-curing step are performed simultaneously. The solution is a thermally conductive silicone composition containing the following components: (A) an organopolysiloxane having aliphatic unsaturated hydrocarbon groups bonded to silicon atoms; (B) an organohydrogen polysiloxane; (C) gallium and / or its alloys with a melting point of -20 to 70°C; (D) a thermally conductive filler with an average particle size of 0.1 to 100 μm; (E) a platinum group metal catalyst; (F-1) an organopolysiloxane with a single end capped with a hydrolyzable group; and (G) an addition reaction control agent. The composition is characterized by having a maximum storage modulus G' when the curing rate is 100%, and a curing rate of 10% at a temperature of 120°C or higher.