At atomize modulo it was produced in production manner of the thermal conductivity silicone rubber constituent for heat dissipation sheet formation and the addition reaction type silicone gel

摘要

PROBLEM TO BE SOLVED: To provide a process whereby a thermally conductive silicone rubber compsn. which is lightweight and highly thermally conductive and has a reduced hardness can be produced at a low cost even when it is highly loaded with a thermally conductive filler by dispersing an aluminum powder produced by the atomizing method, as a thermally conductive filler, in a silicone rubber. SOLUTION: This compsn. is prepd. by dispersing 40-75 vol.% (based on the compsn.) aluminum powder produced by the atomizing method, as a thermally conductive filler, in a silicone rubber. The aluminum powder, produced by the atomizing method, is spherical, has a thermal conductivity of 200 W/mk, a specific gravity of 2.69 g/cm3. and a particle size of 3-250 μm, and contains 25-75 vol.% (based on the aluminum powder) particles having particle sizes of 80 μm or lower. A heat-radiating sheet is obtd. by subjecting the compsn. to sheeting (e.g. by press molding, extrusion, or calendering) and then to thermal curing or by subjecting a substrate (e.g. a glass cloth) to impregnation with the compsn. and then to molding and thermal curing.