| 摘要 |
PURPOSE:To obtain a sponge roll excellent in releasability from a toner and desirable for a fixation roll of an electrostatic copier by mixing an aliphatic unsaturation-free polyorganosiloxane with a finely powdered silica filler, an azodicarbonamide blowing agent and a diacyl peroxide. CONSTITUTION:A silicone sponge roll composition is produced by blending 100 pts.wt. apliphatic unsaturation-free organopolysiloxane of the formula (wherein R is a substituted or unsubstituted monovalent hydrocarbon group or a hydroxyl group; and (a) is 1.95-2.05) (desirably one of a viscosity >=100000 at 25 deg.C) with 3 to 100 pts.wt., desirably 5 to 30 pts.wt. finely powdered silica filler (desirably one of a specific surface area >=1m<2>/g and a mean particle diameter of 0.005 to 5mum), 0.1 to 10 pts.wt., desirably 0.5 to 7 pts.wt. azodicarbonamide blowing agent (one of a decomposition temperature <=160 deg.C, Cellmic CAP-250, a product of Sankyo Kasei), and 0.1 to 10 pts.wt., desirably 0.1 to 3 pts.wt. diacyl peroxide (one of a 10-hr half life decomposition temperature <=100 deg.C). |
