Disclosed is an internal combustion engine lubricating oil composition for reducing corrosion in the engine of a hybrid vehicle. Reduction of corrosion can be determined by the JIS K2246 test method. Also disclosed are methods for using said lubricating oil composition for reducing corrosion in the engine of a hybrid vehicle.

A lubricant composition comprising an oil-soluble polyalkylene glycol; an ester compound selected from the group of natural esters and synthetic esters, and combinations thereof; and an additive mixture comprising an antioxidant and an anticorrosive, wherein the anticorrosive is selected from neutral alkali metal and alkaline earth metal salts of sulfonic acids, carboxylic acids, naphthoic acids, naphthenic acids, benzoic acids and phosphoric acids, and derivatives and combinations thereof.

A complex including an active ingredient, and a surfactant. The active ingredient is one or more less-oil-soluble substances selected from the group consisting of a hardly-oil-soluble substance and an oil-insoluble substance, and the one or more less-oil-soluble substances function as an additive for lubricating oil. A method of making the complex.

A grease composition containing a base oil (A), a urea-based thickener (B), an antioxidant (C), and a rust inhibitor (D), wherein in a particle size distribution curve obtained by measuring the particle size of particles containing the urea-based thickener (B) in the grease composition on a volume basis with light scattering, a peak indicating the maximum frequency satisfies the following Requirements (I) and (II): (I) a particle size indicating the maximum frequency of the peak is 1.0 μm or less; and (II) a half width of the peak is 1.0 μm or less.

Provided is a lubricating oil composition for a transmission having excellent gear properties, clutch properties, cooling properties, and electric insulating properties. The lubricating oil composition for a transmission preparing by blending (A) a base oil, (B) a viscosity index improver having a mass average molecular weight of 10,000 to 50,000, and (C-1) a polyamide and/or (C-2) a polyol ester, the base oil (A) including (A-1) a synthetic oil having a kinematic viscosity at 100 C. of 1.0 to 10.0 mm.sup.2/s.

Metalworking formulations and corrosion inhibitor formulations are provided. The metalworking fluids have excellent performance as coolants in the manufacture of thin-walled metal containers such as aluminum beverage cans.

There is provided a grease composition which is supplied between a plurality of lips provided in a sealing device that seals between a pair of members that rotate relative to each other, wherein the grease composition comprises a base oil (A), a thickening agent (B) and a rust preventive agent (C); a kinematic viscosity of the base oil (A) at 40? C. is 30 to 80 mm.sup.2/s; the thickening agent (B) is a diurea compound represented by Formula (1); and the composition comprises 5 to 15% by mass of the thickening agent (B) and 0.1 to 2.0% by mass of the rust preventive agent (C) based on the total of the grease composition.

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

wherein R.sup.2 is a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 are a linear or branched alkyl group having 8 to 22 carbon atoms.

Thus, a grease composition is provided, which can suppress a torque difference due to a rotation direction and exhibits excellent sealing properties.

Provided is a lubricating oil composition for a transmission having excellent gear properties, clutch properties, cooling properties, and electric insulating properties. The lubricating oil composition for a transmission preparing by blending (A) a base oil, (B) a viscosity index improver having a mass average molecular weight of 10,000 to 50,000, and (C-1) a polyamide and/or (C-2) a polyol ester, the base oil (A) including (A-1) a synthetic oil having a kinematic viscosity at 100 C. of 1.0 to 10.0 mm.sup.2/s.

There is provided a grease composition which is supplied between a plurality of lips provided in a sealing device that seals between a pair of members that rotate relative to each other, wherein the grease composition comprises a base oil (A), a thickening agent (B) and a rust preventive agent (C); a kinematic viscosity of the base oil (A) at 40 C. is 30 to 80 mm.sup.2/s; the thickening agent (B) is a diurea compound represented by Formula (1); and the composition comprises 5 to 15% by mass of the thickening agent (B) and 0.1 to 2.0% by mass of the rust preventive agent (C) based on the total of the grease composition.
R.sup.1NHCONHR.sup.2NHCONHR.sup.3(1) wherein R.sup.2 is a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 are a linear or branched alkyl group having 8 to 22 carbon atoms. Thus, a grease composition is provided, which can suppress a torque difference due to a rotation direction and exhibits excellent sealing properties.

A lubricant composition comprising an oil-soluble polyalkylene glycol; an ester compound selected from the group of natural esters and synthetic esters, and combinations thereof; and an additive mixture comprising an antioxidant and an anticorrosive, wherein the anticorrosive is selected from neutral alkali metal and alkaline earth metal salts of sulfonic acids, carboxylic acids, naphthoic acids, naphthenic acids, benzoic acids and phosphoric acids, and derivatives and combinations thereof.