| 摘要 |
PURPOSE:To obtain a silicone rubber composition for gasket to be used normally in contact with a lubricating oil by adding a specific organopolysiloxane oil or a specific hydrocarbon oil to a silicone rubber composition curable by addition reaction. CONSTITUTION:The objective composition is composed of (A) 100 pts.wt. of an organopolysiloxane having >=2 Si-bonded alkenyl groups in one molecule, (B) an organohydrogen polysiloxane containing >=2 Si-bonded H atoms in one molecule in an amount to give the molar ratio of Si-bonded H atom of the component to Si-bonded alkenyl group of the component A of (0.5-20):1, (C) a platinum-based catalyst in an amount of 0.1-500 pts.wt. (in terms of platinum metal based on 1,000,000 pts.wt. of A=B) and (D) 1-80 pts.wt. of an organopolysiloxane oil free from aliphatic unsaturated bond and Si-bonded H atom in the molecule (preferably dimethylpolysiloxane) and/or a hydrocarbon oil free from aliphatic unsaturated bond and having a viscosity of preferably 1-200,000cps at 25 deg.C. |
