Patent ID: 7527830
Filing Date: 2009-05-05
Classification: C08G,C08L,H01L,Y10T

Abstract:
1. A method for preparing a heat transfer member, comprising: applying a heat conductive silicone composition onto a substrate to form an uncured silicone coating having an outer surface and an inner surface contiguous to the substrate, and heat curing the uncured silicone coating to form a silicone heat conductor comprising a cured skin layer on the outer surface side and a layer having a lower hardness than said cured skin layer on the inner surface side, wherein said heat conductive silicone composition comprises: (a) 100 parts by weight of an organopolysiloxane having at least two alkenyl groups on the molecule, (b) 300 to 5,000 parts by weight of a heat conductive filler, (c) an organohydrogenpolysiloxane having on average at least two silicon-bonded hydrogen atoms on the molecule, in an amount that a molar ratio of Si—H groups in component (c) to alkenyl groups in component (a) is in a range of 0.5 to 10.0, (d) a platinum group base addition reaction catalyst in an amount to give 0.1 to 1,000 ppm of platinum group metal element based on the weight of component (a), and (e) a volatile silane or siloxane compound having on the molecule one alkenyl group providing for addition of an Si—H group thereto, in an amount that a molar ratio of alkenyl groups in component (e) to Si—H groups in component (c) is in a range of 0.01 to 1.5, and wherein said substrate is a plastic film which is strippable from the silicone heat conductor, and the silicone heat conductor is in the form of a sheet.