Thermally conductive silicone composition and method for producing gap filler using said composition

A method for producing the two-component thermally conductive silicone composition, comprising:

• providing a first liquid containing (A) a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (D) an addition catalyst, (E) a thermally conductive filler, and (F) a condensation catalyst;
• providing a second liquid containing (A) the diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (B) a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, (C) at least one selected from (C-1) an organosilicon compound having two or more groups that are at least one selected from a methoxy group and an ethoxy group and not having a hydrocarbon group having 3 or more carbon atoms or a vinyl group, and (C-2) a hydrolysate of the organosilicon compound (C-1), and (E) the thermally conductive filler;
• wherein in a first step of mixing (A) the diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (D) the addition catalyst, (E) the thermally conductive filler, and (F) the condensation catalyst to obtain a first liquid;
• and
• wherein in a second step of mixing (A) the diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (B) the diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, (C) the at least one selected from (C-1) the organosilicon compound having two or more groups that are at least one selected from a methoxy group and an ethoxy group and not having a hydrocarbon group having 3 or more carbon atoms or a vinyl group, and (C-2) the hydrolysate of the organosilicon compound (C-1), and (E) the thermally conductive filler to obtain a second liquid;
• wherein the composition contains, in the total amount of the first liquid and the second liquid that constitute the two-component thermally conductive silicone composition;
• wherein relative to 100 parts by mass of the total amount of the component (A) and the component (B);
• wherein 0.2 parts by mass or more and 5.0 parts by mass or less of the component (C);
• wherein a catalytic amount of the component (D) is provided;
• wherein 300 parts by mass or more and 2,000 parts by mass or less of the component (E);
• wherein a catalytic amount of the component (F) is provided;
• and
• wherein the content of the component (B) is in such the range that a ratio of a number of hydrosilyl groups in the component (B) to a number of alkenyl groups in the component (A) is 1/5 to 7.

A method for producing a gap filler using the two-component thermally conductive silicone composition, comprising:

• providing a first liquid containing (A) a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (D) an addition catalyst, (E) a thermally conductive filler, and (F) a condensation catalyst;
• providing a second liquid containing (A) the diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (B) a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, (C) at least one selected from (C-1) an organosilicon compound having two or more groups that are at least one selected from a methoxy group and an ethoxy group and not having a hydrocarbon group having 3 or more carbon atoms or a vinyl group, and (C-2) a hydrolysate of the organosilicon compound (C-1), and (E) the thermally conductive filler;
• wherein the composition contains, relative to 100 parts by mass of a total amount of the component (A) and the component (B);
• wherein 0.2 parts by mass or more and 5.0 parts by mass or less of the component (C);
• wherein a catalytic amount of the component (D) is present;
• wherein 300 parts by mass or more and 2,000 parts by mass or less of the component (E);
• and
• wherein a catalytic amount of the component (F) is present;
• wherein a content of the component (B) is in such a range that a ratio of a number of hydrosilyl groups in the component (B) to a number of alkenyl groups in the component (A) is 1/5 to 7;
• wherein the gap filler is disposed between a battery unit housing having an iron surface coated at least in part with a cationic electrodeposition coating and a cooler having an aluminum surface;
• wherein a mixing step of mixing the first liquid and the second liquid is performed to obtain a thermally conductive silicone composition;
• wherein an application step of applying the thermally conductive silicone composition to at least one of the battery unit housing and the cooler is performed;
• and
• wherein a curing step of the uncured thermally conductive silicone composition applied in the application step at a temperature of 15° C. or higher and 60° C. or lower is performed.

A method for improving adhesive properties of a cured product of a two-component thermally conductive silicone composition, comprising:

• providing a thermally conductive filler to a metal or a metal surface coated with a cationic electrodeposition coating material under a vibration condition and improving storage stability of the thermally conductive silicone composition, the method comprising:
• separately storing;
• providing a first liquid containing (A) a diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (D) an addition catalyst, (E) a thermally conductive filler, and (F) a condensation catalyst;
• providing a second liquid containing (A) the diorganopolysiloxane having an alkenyl group bonded to a silicon atom, (B) a diorganopolysiloxane having a hydrogen atom bonded to a silicon atom, (C) at least one selected from (C-1) an organosilicon compound having two or more groups that are at least one selected from a methoxy group and an ethoxy group and not having a hydrocarbon group having 3 or more carbon atoms or a vinyl group, and (C-2) a hydrolysate of the organosilicon compound (C-1), and (E) the thermally conductive filler;
• wherein the composition contains, in a total amount of the first liquid and the second liquid that constitute the two-component thermally conductive silicone composition;
• wherein relative to 100 parts by mass of a total amount of the component (A) and the component (B);
• wherein 0.2 parts by mass or more and 5.0 parts by mass or less of the component (C);
• wherein a catalytic amount of the component (D) is provided;
• wherein 300 parts by mass or more and 2,000 parts by mass or less of the component (E);
• wherein a catalytic amount of the component (F) is provided;
• and
• wherein a content of the component (B) is in such a range that a ratio of a number of hydrosilyl groups in the component (B) to a number of alkenyl groups in the component (A) is 1/5 to 7.