Abstract: The invention provides a grease composition for a hub unit bearing employing an angular contact ball bearing, containing (a) as a thickener a mixture of diurea compounds represented by formula (I): R1—NHCONH—R2—NHCONH—R1, formula (II): R1—NHCONH—R2—NHCONH—R3, and formula (III): R3—NHCONH—R2—NHCONH—R3 wherein R1 is cyclohexyl group, R2 is a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, R3 is a straight-chain or branched alkyl group having 12 to 20 carbon atoms, and (R1/(R1+R3))×100=85 to 95 mol %; (b) a base oil; (c) a molybdenum dialkyldithiocarbamate; and (d) a calcium sulfonate. The grease composition of the invention, when used in the hub unit bearing, shows minimum leakage, excellent anti-flaking properties and satisfactory bearing lubrication life.

Abstract: The invention provides a grease composition which contains (a) a base oil, (b) a thickener, (c) a compound having an alkylthiocarbamoyl group, represented by the formula (1), (d) a hindered phenol antioxidant, and (e) a metal deactivator; wherein R1, R2, R3 and R4 are each independently an alkyl group having 1 to 20 carbon groups, and X represents S, S—S, S—CH2—S, S—CH2CH2—S or S—CH2CH2CH2—S.

Abstract: The invention provides a grease composition for a hub unit bearing employing an angular contact ball bearing, containing (a) as a thickener a mixture of diurea compounds represented by formula (I): R1—NHCONH—R2—NHCONH—R1, formula (II): R1—NHCONH—R2—NHCONH—R3, and formula (III): R3—NHCONH—R2—NHCONH—R3 wherein R1 is cyclohexyl group, R2 is a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, R3 is a straight-chain or branched alkyl group having 12 to 20 carbon atoms, and (R1/(R1+R3))×100=85 to 95 mol %; (b) a base oil; (c) a molybdenum dialkyldithiocarbamate; and (d) a calcium sulfonate. The grease composition of the invention, when used in the hub unit bearing, shows minimum leakage, excellent anti-flaking properties and satisfactory bearing lubrication life.

Abstract: A grease composition which has an excellent anti-fretting property and general versatility, and a machine part which uses the same are provided. A grease composition comprising a urea thickener, a base oil, a phosphorothioate compound and an amine compound and a machine part which uses the same are provided.

Abstract: A grease composition which is suitable for a ball bearing exposed to high temperatures and exhibits stable lubricity for a prolonged period of time, and a bearing which encapsulates the grease composition are provided. A grease composition comprising (a) a base oil, (b) a thickener, (c) a compound having alkylthiocarbamoyl group of the general formula (1), and an amine-ketone condensate-based antioxidant. A grease composition further comprising (e) a metal inactivator.