A lubricating grease composition containing a base oil having a kinematic viscosity of 10 mm.sup.2/s or more and 60 mm.sup.2/s or less at 40 C.; a thickener containing at least one soap selected from a metal soap and a metal complex soap; and a solid lubricant containing porous polyamide particles. An amount of the porous polyamide particles blended is 1% by mass or more and 20% by mass or less based on a total mass of the lubricating grease composition.

A composition with a kinematic viscosity for cooling and lubricating a drive system of an electric or hybrid vehicle, measured at 100 C. in accordance with the standard ASTM D445, in the range 3 to 10 mm.sup.2/s. The composition includes 70% to 90% of a base oil or a mixture of base oils having a kinematic viscosity, measured at 100 C. in accordance with the standard ASTM D445, of 1.5 to 8 mm.sup.2/s and selected from polyalphaolefins; and at least one thickening polymer.

This disclosure provides a method for improving wear control, while maintaining or improving energy efficiency, in a mechanical component having sliding or rolling between contacting surfaces. The method involves using a lubricant composition in the mechanical component having sliding or rolling between contacting surfaces. The lubricant composition has a base stock blend as a major component, and at least one lubricant additive, as a minor component. The base stock blend has at least one first base stock having a viscosity from 1 to 50 cSt at 40 C. and at least one second base stock having viscosity from 100 to 2000 cSt at 40 C. The first base stock is present in an amount greater than 50 to 95 wt % of the base stock blend, and the second base stock is present in an amount from 5 to less than 50 wt % of the base stock blend. The second base stock is miscible with the first base stock.

This disclosure relates to grease compositions having at least one base oil, and at least one polyurea thickener. The at least one polyurea thickener is prepared by reacting an isocyanate-terminated prepolymer with at least one amine under reaction conditions sufficient to prepare the at least one polyurea thickener. The isocyanate-terminated prepolymer is prepared by reacting a polyisocyanate with a polyol, at an NCO/OH equivalent ratio of 1.05:1 to 10:1, under reaction conditions sufficient to prepare said isocyanate-terminated prepolymer. When the grease compositions are used under high temperature conditions, structural stability and resistance to breaking down in accordance with DIN 51821 (FAG FE9) is improved. This disclosure also relates to a method of preparing the grease compositions. This disclosure further relates to a method for improving high temperature performance of a grease composition in a mechanical component lubricated with the grease composition.

A lubricant composition contains a lubricant base oil, (A) a detergent containing magnesium, (B) a compound containing boron, and (C) a zinc dialkyl dithiophosphate. The amount of component (A) is in the range of 200 to 1200 mass ppm [Mg] based on the mass of the lubricant composition, and the amount of component (C) is in the range of 300 to 1000 mass ppm [P] based on the mass of the lubricant composition. Component (C) includes a zinc dialkyl dithiophosphate having a primary alkyl group or a secondary alkyl group; the lubricant composition includes zinc dialkyl dithiophosphate having a secondary alkyl group; the mass ratio of the zinc dialkyl dithiophosphate having a primary alkyl group and the zinc dialkyl dithiophosphate having a secondary alkyl group is from 70:30 to 0:100; and the concentration of [B] is from 100 to 300 mass ppm based on the mass of the lubricant composition.

A grease composition includes base oil, a thickener, and an inorganic additive. The base oil is a poly--olefin having a base oil kinematic viscosity of 15 to 50 mm.sup.2/s at 40 C. The thickener is a diurea expressed by Structural Formula (1). The content of the thickener is 10 to 22 mass % with respect to the total amount of the base oil and the thickener. The inorganic additive is a mixture containing sepiolite and bentonite, and is organically modified. The content of the inorganic additive is 2 to 20 mass % with respect to the total amount of the base oil and the thickener.

R.sup.1NHCONHR.sup.2NHCONHR.sup.3 (1)

Object

A grease composition having a low dust generation, long life, and low low-temperature torque under an ultra high-speed, high-temperature environment with a rotational speed exceeding 30000 rpm is provided, and by applying the grease composition to a rolling bearing, the rolling bearing having a low dust generation, long life and low low-temperature torque, and a motor including such a rolling bearing are also provided.

Resolution Means

Provided are: a grease composition containing a base oil and a thickener, the base oil including a fluorine oil, an ester oil, and a polyalphaolefin oil, and the thickener including a fluorine-based thickener, a urea-based thickener, and a barium complex soap thickener, each of these components being included in the grease composition at a predetermined proportion; a rolling bearing filled with the grease composition; and a motor including the rolling bearing.

A fullerene-containing lubricating oil composition including a base oil and fullerene, wherein the fullerene is dissolved, and the concentration is 1 ppm by mass or more and less than 50 ppm by mass.

A lubricating oil composition containing a base oil (A) and a thiadiazole-based compound (B). A content of a sulfurized olefin is less than 0.20 mass % based on the total amount of the lubricating oil composition, and a kinematic viscosity of the lubricating oil composition at 100 C. is 2.1 mm.sup.2/s or more and less than 5.0 mm.sup.2/s.

Provided are: a lubricating oil composition satisfying both high viscosity index and high shear stability, which contains a base oil having a kinematic viscosity at 40 C. of 4.0 mm.sup.2/s or more and less than 6.0 mm.sup.2/s, a kinematic viscosity at 100 C. of 1.0 mm.sup.2/s or more and less than 2.0 mm.sup.2/s, and a flash point of 140 C. or higher, and a polymethacrylate having a specific structure; and a lubrication method and a transmission each using the lubricating oil composition.