Abstract: The invention provides a grease composition containing a base oil, a thickener and a rust inhibitor, characterized in that the rust inhibitor includes an organic sulfonate and a fatty acid amine salt. The grease composition of the invention exhibits excellent rust preventing characteristics and causes little damage to the environment.

Abstract: The invention provides a grease composition for rolling bearings of automotive electrical equipment or automotive auxiliaries, containing a base oil that includes as an essential component an alkyldiphenyl ether oil; a diurea thickener represented by formula (1); an anti-flaking additive including an organic sulfonate rust inhibitor and a load carrying additive; and an antioxidant. In the formula (1), R2 is a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms; and one of R1 or R3 represents cyclohexyl group and the other represents cyclohexyl group, an alkyl group having 8 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms.

Abstract: A grease composition for EV/HEV driving motor bearing, containing a diurea thickener of the following formula (A): wherein R1, R2 and R3 are defined, with the ratio of the number of moles of the straight-chain or branched alkyl group having 16 to 20 carbon atoms to the total number of moles of the cyclohexyl group and the straight-chain or branched alkyl group having 16 to 20 carbon atoms, expressed as [((the number of alkyl group)/(the number of cyclohexyl group+the number of alkyl group))×100] being 60 to 80%, and a base oil which has a kinematic viscosity at 40° C. of 15 to 50 mm2/s and includes a trimethylolpropane ester oil in an amount of 80 mass % or more based on the total base oil mass. The grease composition can exhibit a long bearing lubrication life at high temperature and high speed, and satisfactory low-temperature flowability.

Abstract: A grease composition for a rolling bearing for a motor to support a rotor of the motor, containing a pentaerythritol ester base oil with a kinematic viscosity at 40° C. of 20 to 55 mm2/s; 7 to 13 mass % of a diurea thickener represented by formula (A) where each R group is defined; and a rust inhibitor mixture selected from the group consisting of polyol ester type rust inhibitors and organic sulfonate type rust inhibitors. The grease composition can prevent a peculiar noise from being produced at low temperatures, satisfy the low torque performance over a wide temperature range, extend the bearing lubrication life even under the circumstances of high temperature, and exhibit excellent rust inhibiting effect on varnish.

Abstract: The invention provides a grease composition for rolling bearings of automotive electrical equipment or automotive auxiliaries, containing a base oil that includes as an essential component an alkyldiphenyl ether oil; a diurea thickener represented by formula (1); an anti-flaking additive including an organic sulfonate rust inhibitor and a load carrying additive; and an antioxidant. In the formula (1), R2 is a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms; and one of R1 or R3 represents cyclohexyl group and the other represents cyclohexyl group, an alkyl group having 8 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms.

Abstract: A grease composition for EV/HEV driving motor bearing, containing a diurea thickener of the following formula (A): wherein R1, R2 and R3 are defined, with the ratio of the number of moles of the straight-chain or branched alkyl group having 16 to 20 carbon atoms to the total number of moles of the cyclohexyl group and the straight-chain or branched alkyl group having 16 to 20 carbon atoms, expressed as [((the number of alkyl group)/(the number of cyclohexyl group+the number of alkyl group))×100] being 60 to 80%, and a base oil which has a kinematic viscosity at 40° C. of 15 to 50 mm2/s and includes a trimethylolpropane ester oil in an amount of 80 mass % or more based on the total base oil mass. The grease composition can exhibit a long bearing lubrication life at high temperature and high speed, and satisfactory low-temperature flowability.

Abstract: The invention provides a grease composition for rolling bearings of automotive electrical equipment or automotive auxiliaries, where a base oil contains as an essential component an alkyldiphenyl ether oil; a thickener is a diurea compound represented by the following formula (1): (wherein R2 is a diphenylmethane group; and R1 and R3, which may be the same or different represent an aromatic hydrocarbon group having 6 to 12 carbon atoms); and an anti-flaking additive that contains an organic sulfonate rust inhibitor and a load carrying additive. The grease composition of the invention can extend the bearing lubrication life even at elevated temperatures and exhibit excellent anti-flaking properties, so that the grease composition can be enclosed in the rolling bearings of automotive electrical equipment or automotive auxiliaries.

Abstract: A grease composition for a rolling bearing for a motor to support a rotor of the motor, containing a pentaerythritol ester base oil with a kinematic viscosity at 40° C. of 20 to 55 mm2/s; 7 to 13 mass % of a diurea thickener represented by formula (A) where each R group is defined; and a rust inhibitor mixture selected from the group consisting of polyol ester type rust inhibitors and organic sulfonate type rust inhibitors. The grease composition can prevent a peculiar noise from being produced at low temperatures, satisfy the low torque performance over a wide temperature range, extend the bearing lubrication life even under the circumstances of high temperature, and exhibit excellent rust inhibiting effect on varnish.

Abstract: The invention provides a grease composition containing a base oil, a thickener and a rust inhibitor, characterized in that the rust inhibitor includes an organic sulfonate and a fatty acid amine salt. The grease composition of the invention exhibits excellent rust preventing characteristics and causes little damage to the environment.

Abstract: An object of the invention is to provide a grease composition capable of keeping a good lubrication condition for a long period of time even when water has mixed therein, thereby inhibiting white structure flaking and corrosion. Another object is to provide a vehicular hub unit bearing which hardly suffers from white structure flaking and corrosion even when used in an environment where water may penetrate into it and which therefore has a long life. The invention provides a rolling bearing with, sealed up therein, a grease composition containing a waterproof film-forming additive added thereto; a grease composition for hub unit bearings, containing a base oil that comprises at least one of mineral oil and synthetic oil as the main ingredient thereof, and a thickener and a flaking inhibitor; and a vehicular hub unit bearing with the grease composition sealed up therein.