Low torque grease composition

摘要

There is provided a grease composition useful for bearings of cars and aircraft which is stable in a wide range of temperature of 40 to 180 DEG C and exhibits low torque properties under high loading at low temperatures. A low torque grease composition having dynamic viscosity (40 DEG C) of 40 to 150 mm<2>/sec which comprises a base oil consisting of (a) straight-chain perfluoropolyether oil having dynamic viscosity (40 DEG C) of 25 mm<2>/sec or less and represented by the following general formula: RfO(CF2O)p(C2F4O)q(C3F6O)rRf, wherein Rf is a perfluoro lower alkyl group and all of p, q and r is an integer and a sum thereof is an integer of 25 to 45 and (b) straight-chain perfluoropolyether oil having dynamic viscosity (40 DEG C) of 250 mm<2>/sec or more and represented by the following general formula: RfO(CF2O)p(C2F4O)q(C3F6O)rRf, wherein Rf is a perfluoro lower alkyl group and p, q and r are an integer of 10 to 20; and (c) polytetrafluoroethylene as a thickener.