Sheet-like heat dissipation member and thermally conductive composite

Abstract

Provided is a heat dissipation member that exhibits good adhesion to heat-generating electronic components and heat dissipation components, has good thermal conductivity and insulating properties, and is superior in reliability. A sheet-like heat dissipation member includes a composition layer formed of a thermosoftening thermally conductive composition containing: (A) a silicone resin being solid at 25° C. and having one or more types of siloxane units selected from R1SiO3/2 units, where R1 is a monovalent hydrocarbon group having 1 to 10 carbon atoms, and the SiO4/2 unit; and (B) thermally conductive filler composed of: (B-1) 120 to 1750 parts by mass of alumina having an average particle diameter of 0.1 to 70 μm; and (B-2) aluminum nitride having an average particle diameter of 0.1 to 70 μm and a specific surface area of 4.0 m2/g or less, wherein the mass ratio (B-1)/(B-2)=1/9 to 1/1.

Dependencies are inferred from the claim text.