PURPOSE: To provide a sealing material made of an oil-bleeding fluorosiliocone rubber which has excellent resistance to oils, solvents, weather, heat and cold, by vulcanizing and molding a compound consisting of a specified organopolysiloxane, reinforcing silica and an oily organopolysiloxane.
CONSTITUTION: A compound consisting of 100pts.wt. organopolysiloxane (A) having a viscosity of not lower than 100 cps and the average compositional formula I [wherein R is composed of at least 25mol% of a perfluoroalkylalkyl group and 75W50mol% of CH3, C2H5, phenyl and vinyl groups; a is a number of 1.98W2.02; and b is a number of (4-a)/2], 10W50pts.wt. reinforcing silica (B) having a surface area of not smaller than 50m2/g, such as fumed silica, 3W10pts. wt. oily organopolysiloxane (C) of formula II (wherein R2 is composed of 70W25% CH3 and 30W75% pnenyl; and n is a number of 0W5) and optionally not more than 100pts.wt. semi-reinforcing silica powder (D) having an average particle size of not larger than 5μ, such as quartz powder is mixed with a vulcanizing agent (E). The mixture is vulcanized by heating and molded to obtain a sealing material suitable for use in the production of a non-tackly bevel sealing valve of a check valve.
| WO/2008/089910 | VALVE DEVICE FOR A LOW-PRESSURE SUPPLY SYSTEM |
| WO/2003/001096 | PRESSURE SENSITIVE ONE-WAY VALVE |
KOBAYASHI ATSUSHI
NISHISHINA HIRONORI
KUROSAWA SHUNEI
