Addition-curable silicone composition, method for manufacturing the same, and optical semiconductor device

A method for manufacturing an addition-curable silicone composition, comprising:

• (A) organopolysiloxane having at least two alkenyl groups having 2 to 10 carbon atoms and being bonded to a silicon atom per molecule;
• (B) an organosilicon compound having at least two silicon atom-bonded hydrogen atoms per molecule, wherein an amount of the silicon atom-bonded hydrogen atoms in the component (B) is 0.1 to 4.0 mol relative to 1 mol of the alkenyl groups in the component (A);
• (C) a platinum group metal-based catalyst, wherein an amount of the platinum group metal-based catalyst is a catalytic amount;
• and
• (D) an inorganic oxide particle,
• wherein, the method for manufacturing an addition-curable silicone composition comprises the step of:
• providing the inorganic oxide particle;
• manufacturing a surface-treated inorganic oxide particle by surface-treating the inorganic oxide particle with a polysilazane compound-containing composition that contains an organic solvent and a polysilazane compound, in which a ratio of a number of repeating units represented by the following formula (2) is 0 to 0.5 relative to a total number of repeating units represented by the following formulae (1) and (2), and in which an amount of the polysilazane compound is 0.1 to 20% by mass relative to a total amount of the polysilazane compound and the organic solvent;
• and
• manufacturing the addition-curable silicone composition by mixing the surface-treated inorganic oxide particle with the components (A) to (C),
• wherein, R represents a group selected from the group consisting of an aliphatic hydrocarbon group having 1 to 6 carbon atoms, an aromatic hydrocarbon group having 6 to 12 carbon atoms, and an alkoxy group having 1 to 6 carbon atoms, and Rs in a polysilazane compound molecule may be the same or different each other.