Abstract: A sliding member used as a sealing ring for a rotary shaft made of a lightweight aluminum alloy in an automatic transmission instead of a conventional cast iron sealing ring in order to prevent leakage of oil and reduce abrasion of the shaft consists of a PEEK resin composition which includes, as binder, 15.about.20 percent by weight of amorphous alumina powder having an average particle diameter of 5.mu. or less, 3.about.8 percent by weight of graphite powder having an average particle diameter of 5.mu. or less and 6.about.9 percent by weight of carbon powder having an average particle diameter of 30.mu. or less.

Abstract: A sliding material for light metal material contains polyether-ether ketone and/or polyether-nitride. Further, 20.about.35% of sericite is added in the sliding material as a solid lubricant to improve self-wear resistance of the sliding material and wear resistance of a mating part with respect to the sliding material.

Abstract: A a seal ring is made of a synthetic resin and has opposite ends. The seal ring has been imparted with shape-retentive property so that the seal ring is crossed at portions thereof located inside the opposite ends. The seal ring preferably has a smaller radius of curvature around the crossed portions and also around a portion thereof located diametrically opposite the crossed portions than around remaining portions thereof. Desirably, the seal ring may be in a substantially elliptic shape. The seal ring may preferably be symmetrical relative to a line extending between the crossed portions and a portion thereof located diametrically opposite the crossed portions.

Abstract: A sliding member having a coating especially suitable for a piston ring or a cylinder liner in which excellent wear- and scuff-resistance, as well as excellent initial wear-in property are required. The coating is produced by plasma-arc flame spraying a mixed powder comprising molybdenum powder, nickel-chromium alloy powder and titanium carbide powder on a base surface of the sliding member made of iron or steel.

Abstract: In a sliding mechanism including a first sliding surface, a sliding member having a second sliding surface which contacts with the first sliding surface and slides relatively to the first sliding surface, and a holding member holding the sliding member in contact, while moved, at least a contact portion of the seal member with the holding member is made of polytetrafluoroethylene resin containing iron alloy powder.