| 摘要 |
PURPOSE:To provide the title compsn. which allows the manufacturing process of membrane keyboards to be simplified, consisting of a polyorganosiloxane, a polyorganohydrogensiloxane, a platinum catalyst, a specified reaction product, an inorg. filler, etc. CONSTITUTION:100pts.wt. polyorganosiloxane (A) having at least two structural units of formula I [wherein R<1> is an alkenyl; R<2> is a (substd.) monovalent hydrocarbon group having no aliph. unsaturated bond; a is 1 or 2; b is 0 or a; a+b=1-3] is blended with a polyorganohydrogensiloxane (B) having at least three SiH bonds, composed of a structural unit of formula II [wherein R<3> is a (substd.) monovalent hydrocarbon group; c is b; d is a; c+d=1-3] in such an amount as to give 0.5-4.0 SiH group per one alkenyl group in the components A, B and D, 0.1-100ppm (in terms of platinum, based on the amount of the component) of a platinum catalyst (C), 10-1,000pts.wt. reaction product (D) of a branched polyorganosiloxane having 0.4-1.0mol of a unit of formula III (wherein R<4> is R<3>) per mol of SiO2 unit with a polydiorganosiloxane having a viscosity of 30-80,000,000cP (25 deg.C), an inorg. filler (E) and a bonding aid (F). |
