The present invention relates to provision of an extreme pressure agent-containing grease composition using, as a thickener, a urea-based thickener, the grease composition being excellent in both torque transmitting efficiency and leakage prevention performance and also excellent in wear resistance and load resistance. The grease composition contains a base oil (A), a urea-based thickener (B), and an extreme pressure agent (C), wherein particles containing the urea-based thickener (B) in the grease composition satisfies the following requirement (I): Requirement (I): an arithmetic average particle diameter of the particles on an area basis as measured by the laser diffraction/scattering method is 2.0 μm or less, and the extreme pressure agent (C) is at least one selected from an organic metal-based extreme pressure agent, a sulfur-based extreme pressure agent, a phosphorus-based extreme pressure agent, and a sulfur-phosphorus-based extreme pressure agent.

The present invention relates to provision of an extreme pressure agent-containing grease composition using, as a thickener, a urea-based thickener, the grease composition being excellent in both torque transmitting efficiency and leakage prevention performance and also excellent in wear resistance and load resistance. The grease composition contains a base oil (A), a urea-based thickener (B), and an extreme pressure agent (C), wherein particles containing the urea-based thickener (B) in the grease composition satisfies the following requirement (I): Requirement (I): an arithmetic average particle diameter of the particles on an area basis as measured by the laser diffraction/scattering method is 2.0 μm or less, and the extreme pressure agent (C) is at least one selected from an organic metal-based extreme pressure agent, a sulfur-based extreme pressure agent, a phosphorus-based extreme pressure agent, and a sulfur-phosphorus-based extreme pressure agent.

A lubricant grease composition is disclosed, the lubricant grease composition including a base oil and a thickener. The thickener includes an aluminum-based complex soap and a polyurea thickener, wherein the lubricant grease is configured for lubrication of surfaces of components in which an upper use temperature of the lubricant grease composition is at least 90° C.

A lubricant grease composition is disclosed, the lubricant grease composition including a base oil and a thickener. The thickener includes an aluminum-based complex soap and a polyurea thickener, wherein the lubricant grease is configured for lubrication of surfaces of components in which an upper use temperature of the lubricant grease composition is at least 90° C.

Provided is a rolling bearing using a retainer, particularly a highly reliable retainer in which dimensional stability required for a retainer of an outer ring guide type, ductility required for a crown-type retainer, improvement in adhesion of grease with a poly-α-olefin oil or the like as a base oil, and deformation prevention at a high speed can be achieved. The rolling bearing includes at least an inner ring 1, an outer ring 3, a synthetic resin retainer 9, and a rolling element 7, in which the synthetic resin retainer 9 is formed of a polyamide resin composition including polyamide 410 and a reinforcing fiber material with a content of 0% by weight to 40% by weight.

Provided is a rolling bearing using a retainer, particularly a highly reliable retainer in which dimensional stability required for a retainer of an outer ring guide type, ductility required for a crown-type retainer, improvement in adhesion of grease with a poly-α-olefin oil or the like as a base oil, and deformation prevention at a high speed can be achieved. The rolling bearing includes at least an inner ring 1, an outer ring 3, a synthetic resin retainer 9, and a rolling element 7, in which the synthetic resin retainer 9 is formed of a polyamide resin composition including polyamide 410 and a reinforcing fiber material with a content of 0% by weight to 40% by weight.

A refrigerating machine oil containing a hydrocarbon base oil having a 90% distillation temperature of 270° C. or lower.

A grease composition for resin lubrication, the grease composition to be applied to a sliding surface made of resin, the grease composition containing: a fluorine-based base oil (a kinematic viscosity at 40° C. of 300 mm.sup.2/s or higher) and a synthetic hydrocarbon oil as base oils; a fluorine-based thickener, and a lithium soap thickener or a lithium complex soap thickener as thickeners; and a fluorine-based surfactant and an extreme pressure additive as additives; and a resin sliding member (slide switch) having a sliding surface made of resin, the sliding surface provided by application with the grease composition.

A grease composition for resin lubrication, the grease composition to be applied to a sliding surface made of resin, the grease composition containing: a fluorine-based base oil (a kinematic viscosity at 40° C. of 300 mm.sup.2/s or higher) and a synthetic hydrocarbon oil as base oils; a fluorine-based thickener, and a lithium soap thickener or a lithium complex soap thickener as thickeners; and a fluorine-based surfactant and an extreme pressure additive as additives; and a resin sliding member (slide switch) having a sliding surface made of resin, the sliding surface provided by application with the grease composition.

A grease composition is intended primarily for use in constant velocity joins (CV joints), especially ball joints and/or tripod joints, which are used in the drivelines of motor vehicles. The grease composition for use in constant velocity joints comprises at least one base oil, and least one thickener, at least one copper sulfide in an amount of approximately 0.01 wt-% up to approximately 1.5 wt-% of the grease composition, molybdenum disulfide and/or at least one phosphor-free organic molybdenum complex in an amount of approximately 0.1 wt-% up to approximately 5.0 wt-% of the grease composition. Further, a constant velocity joint comprises the grease composition.