Thermally conductive silicone composition and method for producing thermally conductive cured product using the composition

A method for improving a resiliency of a cured product obtained by curing a thermally conductive silicone composition, the method comprising:

• adding a component (D) that is a silicone resin having a number-average molecular weight of 1,000 or more to a thermally conductive silicone composition that contains a component (A) that is a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, with a viscosity, at 25° C., of 10 mPa·s or more and 1,000,000 mPa·s or less, a component (B) that is a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, with a viscosity, at 25° C., of 10 mPa·s or more and 1,000,000 mPa·s or less, a component (C) that is a thermally conductive filler, and a component (E) that is an addition reaction catalyst;
• applying the resulting thermally conductive silicone composition in a liquid state to a substrate;
• and
• curing the thermally conductive silicone composition to obtain the cured product with an improved resiliency.

A method for producing a gap filler, comprising:

• applying, to a substrate, a thermally conductive silicone composition in a liquid state, the composition containing
• a component (A) that is a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, with a viscosity at 25° C. of 10 mPa·s or more and 1,000,000 mPa·s or less,
• a component (B) that is a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, with a viscosity at 25° C. of 10 mPa·s or more and 1,000,000 mPa·s or less,
• a component (C) that is a thermally conductive filler,
• a component (D) that is a silicone resin having at least one alkenyl group within one molecule, with a number-average molecular weight of 1,000 or more, and
• a component (E) that is an addition reaction catalyst, wherein
• a content of the component (C) is 300 parts by mass or more and 2,000 parts by mass or less relative to 100 parts by mass of a total amount of the components (A) and (B), and
• a content of the component (D) is 1 part by mass or more relative to 100 parts by mass of the total amount of the components (A) and (B);
• and
• curing the applied thermally conductive silicone composition.

A gap filler comprising a cured product of a thermally conductive silicone composition, wherein:

• the composition containing
• a component (A) that is a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, with a viscosity at 25° C. of 10 mPa·s or more and 1,000,000 mPa·s or less,
• a component (B) that is a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, with a viscosity at 25° C. of 10 mPa·s or more and 1,000,000 mPa·s or less,
• a component (C) that is a thermally conductive filler,
• a component (D) that is a silicone resin having at least one alkenyl group within one molecule, with a number-average molecular weight of 1,000 or more, and
• a component (E) that is an addition reaction catalyst;
• the gap filler exhibits an improved resiliency due to the component (D) added to the composition;
• and
• a content of the component (C) is 300 parts by mass or more and 2,000 parts by mass or less, and a content of the component (D) is 1 part by mass or more and 10 parts by mass or less, relative to 100 parts by mass of a total amount of the components (A) and (B) in the thermally conductive silicone composition.