| abstract |
A curable silicone composition characteristically comprises (A) (A-1) a dialkylpolysiloxane that has at least two alkenyl groups in each molecule and a viscosity of at least 1,000 mPa•s to not more than 50,000 mPa•s and (A-2) an alkenyl-containing, resin-form organopolysiloxane that comprises the SiO 4/2 unit, R 1 R 2 SiO 1/2 unit, and R 1 n 3 SiO 1/2 unit wherein R 1 is alkyl and R 2 is alkenyl and that contains the alkenyl group in the range from at least 0.5 mass% to less than 3.5 mass%; (B) an organopolysiloxane that has at least three silicon-bonded hydrogen atoms; and (C) a hydrosilylation reaction catalyst and provides a highly transparent cured silicone material that characteristically has a hardness is in the range from at least 30 to not more than 80, the parallel light transmittance at 25 °C is at least 90%, and the parallel light transmittance at 200 °C is a value that is at least 99% of the parallel light transmittance at 25 °C. |