PURPOSE: To provide a non-aqueous electro viscous fluid having excellent heat and cold resistance and high electro viscous effect and requiring only a low consumption electric power by dispersing specific carbonaceous fine particles in an electrically insulating oil, the surfaces of the carbonaceous fine powder being covered with the thin film layers of a high molecular polymer.
CONSTITUTION: The objective electro viscous fluid is prepared by dispersing fine particles in an electrically insulating oil, the fine particles being prepared by covering the surfaces of carbonaceous fine particles having aC/H ratio of 2.4-3.0 with the thin film layers of a polymer such as poly methyl methacrylate, PS, PVAc, PVC, poly vinylidene fluoride, epoxy resin, phenolic resin or silicone polymer. The carbonaceous fine particles are preferably those prepared by separating from a pitch component optically isotropic small spheres produced by the thermal treatment of coal tar.
KITAMURA TAKASHI
ENDO SHIGEKI
FUJIO RYOTA
SAITO TASUKU
