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 lubricating oil composition for a transmission, the composition including: (A) a lubricant base oil comprising a mineral base oil and/or a synthetic base oil; and (B) a poly(meth)acrylate having a weight average molecular weight of no more than 25,000, wherein the composition has a kinematic viscosity at 100° C. of 2.5 to 4.9 mm.sup.2/s.

A refrigerating machine oil having a flash point of 130° C. or lower and a carbon residue of 10% residual oil of 0.02% by mass or more.

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

This invention provides a water-glycol hydraulic fluid comprises from 0.2 to 0.6% by mass of a dimer acid as a fatty acid lubricant, and more than 0.10% by mass and 0.20% by mass or less of a phosphoric acid ester of Formula (1), wherein the sum of the dimer acid and the phosphoric acid ester is more than 0.35% by mass wherein R.sub.1 and R.sub.2 may be the same or different, each representing a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, R.sub.3 represents a hydrocarbon group having from 1 to 20 carbon atoms, R.sub.4 represents a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, and X.sub.1, X.sub.2, X.sub.3 and X.sub.4 may be the same or different, each representing an oxygen atom or a sulfur atom.

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A lithium-based grease and the preparation method thereof are provided. The raw materials for preparing the lithium-based grease include in parts by weight: 75-88 parts of base oil, 0.5-2.5 parts of antiwear agent, 0.1-1.5 parts of antirust agent, 0.1-1.5 parts of antioxidant, 5-25 parts of lubricant, 5-15 parts of thickening agent, and 0.6-2.0 parts of saponifying agent. The raw materials also include hydroxyl compound-containing modified graphene containing quaternary ammonium salt or aromatic ring. The grease has good colloid stability and mechanical stability, can greatly improve the antiwear property. More than that, the grease has excellent oxidation resistance, and can significantly shorten the reaction time of the saponification, reduce the reaction temperature of the saponification.

The disclosed technology relates to a lubricant composition for automotive gears, axles and bearings, the lubricant composition containing an oil of lubricating viscosity and an oil-soluble titanium compound in place of boron compounds, as well as a method of obtaining thermal stability performance in automotive gears, axles and bearings without the boron content that is typical, by lubricating such automotive gears, axles and bearings with a lubricant composition containing an oil-soluble titanium compound and an amine-containing phosphorus rainwear agent.

The refrigerating machine oil according to the present invention contains a lubricating base oil having a kinematic viscosity at 40° C. of 10 mm.sup.2/s or less, and an oiliness agent containing at least one selected from the group consisting of an ester oiliness agent and an ether oiliness agent.

A gear lubricant composition includes at least 97% by weight, based on the total weight of the lubricant composition, of at least one hydrocarbon-based oil that includes a weight content of isoparaffins ranging from 90 to 0%, a weight content of normal paraffins ranging from 0 to 10% and a carbon content of biological origin greater than or equal to 90% relative to the total weight of the oil, at least 0.01% by weight, based on the total weight of the lubricant composition, of at least one additive selected among the anti-wear additives, extreme pressure additives, anti-corrosion additives, additives having metal-deactivating properties, anti-foam additives, anti-oxidant additives selected among the phenolic anti-oxidants, and the mixtures thereof.

The present disclosure generally relates to a lubricating oil composition comprising: a major amount of an oil of lubricating viscosity, one or more detergents comprising at least one alkylhydroxybenzoate compound, and an ashless sulfur compound. Also provided is a method of lubricating an engine with said lubricating oil composition.