| abstract |
(A) an organopolysiloxane having at least two silicon-bonded alkenyl groups in one molecule, (B) an organopolysiloxane having at least two silicon-bonded alkenyl groups in one molecule, An organohydrogenpolysiloxane having at least two silicon atom-bonded hydrogen atoms in its molecule, (C) an organic compound having an organic value of 175 or more in an organic conceptual diagram and having a specific group, and (D) a catalyst for hydrosilylation reaction At least the curable silicone composition. In addition, a silver electrode or a silver-plated substrate in the optical semiconductor device is sealed or covered with a cured product of the composition, which is excellent in reliability after the internal sulfur test. |