| abstract |
A condensation curable silicone rubber composition is provided which is able to suppress increases in viscosity over time, has an adequate pot life and excellent mold releasability, and displays favorable urethane molding durability. The composition includes: (A) an organopolysiloxane represented by a general formula (I), n n n wherein, each R 1 represents, independently, a substituted or unsubstituted monovalent hydrocarbon group, and n represents a number which results in a viscosity at 25° C. of 100 to 500,000 mm 2 /s, with a viscosity at 25° C. of 100 to 500,000 mm 2 /s; (B) a surface-treated reinforcing fine silica powder with a specific surface area as measured by a BET method of at least 50 m 2 /g, and a tap density of 0.2 to 0.4 g/ml, which has undergone treatment with an organosilicon compound to produce a quantity of surface carbon of at least 2.5% by weight; and (C) a tin compound-based curing catalyst. |