Abstract: A thermal interface composition undergoes a viscoelastic change at microprocessor operating temperatures to transfer heat generated by a heat source, such as a microprocessor to a heat sink. The composition includes a low melting alloy dispersed in a matrix. The matrix comprises a viscoelastic composition which softens at about the operating temperature of the heat source. The viscoelastic composition may include a thermoplastic elastomer, a compatible hydrocarbon oil, and a tackifying resin. In use, the thermal interface composition flows under pressure between the heat source and the heat sink to make thermal contact between the two. When the heat source is operated and reaches operating temperature, the viscoelastic composition softens and the low melting alloy melts at around the operating temperature to form a highly thermally conductive, generally homogeneous mixture which readily transfers heat to the heat sink.

Abstract: Disclosed is a thermal interface composition which undergoes a viscoelastic change at microprocessor operating temperatures to transfer heat generated by a heat source to a heat sink, the composition comprising: (A) a viscoelastic composition which softens at about the operating temperature of the heat source, the viscoelastic composition comprising: (1) a thermoplastic elastomer, (2) a compatible hydrocarbon oil, and (3) a tackifying resin; (B) a dispersing agent; and (C) a thermally conductive filler dispersed within the viscoelastic composition. Also disclosed is a method for making the thermal interface composition.

Abstract: Disclosed is a thermal interface composition which undergoes a viscoelastic change at microprocessor operating temperatures to transfer heat generated by a heat source to a heat sink, the composition comprising:

Abstract: A thermal interface composition undergoes a viscoelastic change at microprocessor operating temperatures to transfer heat generated by a heat source, such as a microprocessor to a heat sink. The composition includes a low melting alloy dispersed in a matrix. The matrix comprises a viscoelastic composition which softens at about the operating temperature of the heat source. The viscoelastic composition may include a thermoplastic elastomer, a compatible hydrocarbon oil, and a tackifying resin. In use, the thermal interface composition flows under pressure between the heat source and the heat sink to make thermal contact between the two. When the heat source is operated and reaches operating temperature, the viscoelastic composition softens and the low melting alloy melts at around the operating temperature to form a highly thermally conductive, generally homogeneous mixture which readily transfers heat to the heat sink.

Abstract: A thermally conductive conformable interface layer for use in mounting electronic devices such as transistors or the like onto the surface of a chassis or heat sink. The thermally conductive interface material forms a highly conductive thermal bridge or transfer medium between the external surfaces of the electronic device and the heat sink. The thermally conductive material comprises a multi-layer laminate, typically a polymeric thermally conductive layer along with a film of adhesive bonded thereto. The polymeric layer is preferably a silicone resin, such as polydimethylsiloxane blended with a thermoplastic adhesive such as linear saturated polyester. The polydimethylsiloxane may be filled with a thermally conductive material such as graphite with an adhesive layer being utilized to attach the polymeric layer onto the device and heat sink.

Abstract: A mechanically conformable thermally conductive interface for use in electrically isolating and thermally connecting printed circuit boards to either beat sinks, metal chasses, or heat spreaders. The interface material utilizes silicone polymers of controlled molecular weight and a surface layer of a pressure sensitive adhesive may be employed. The silicone polymer is filled with a thermally conductive electrically insulative particulate such as alumina and/or boron nitride, with the silicone being prepared as a reaction product of a liquid organosiloxane together with a chain extender such as a hydride terminated polydimethylsiloxane material. A release film such as polyethylene may be utilized as the undersurface layer, if desired.