Abstract: A grease composition, which comprises a base oil selected from at least one of synthetic hydrocarbon oil, ester-based synthetic oil, and ether-based synthetic oil; a thickening agent selected from at least one of lithium-based soap, lithium-based complex soap, and a urea-based compound; polytetrafluoroethylene resin powders having a number average molecular weight Mn of 20,000-100,000; and zinc dialkyldithiophosphate having straight or branched alkyl groups of at least carbon atoms, preferably 5-13 carbon atoms, and more preferably 8-12 carbon atoms, has not only a distinguished lubricability, when applied to plastic members, but also a distinguished durability as given by change in friction coefficient and wear loss, after the sliding test.

Abstract: A method of formation of a coating film on the surface of a cylindrical base material such as a piston wherein a waste of the lubricant coating solution is prevented and a lubrication action is maintained. A cylindrical base material is rotably supported horizontally on a rotating support device and in rotation, a coating solution is supplied to a coating surface, and a coating film is coated on the surface of the cylindrical base material. A coating former equipped with a blade is inclined at an angle of 20° to 80° with respect to a tangential direction of rotation, the blade is separated from the coating surface by exactly a coating layer thickness, and further the cylindrical base material is rotated by ¼ of a turn or more.

Abstract: A coating layer forming apparatus for minimizing the amount of the coating solution when forming a coating layer on a part and enhancing a dimensional precision of a formed surface of the coating layer. The coating layer forming apparatus has a rotation supporting device, a feeder (15), a layer former, and a coating removing device, maintains the inclined angle of a coating former for forming the coating layer at 30 to 70 degrees with respect to a tangential direction of rotation of a coating of a coating surface, and removes excess coating solution deposited on the coating former by a coating removing device.