A lubricating oil composition excellent in the wear resistance and a refrigerator oil composition excellent in the oxidation stability using the lubricating oil composition are provided by a lubricating oil composition containing a base oil (A) and a phosphine derivative (B) having one or more oxygen atom in a molecule.

An object is to provide a grease composition for a ball joint capable of reducing the starting torque, reducing the operating torque, and improving the low temperature property as compared with the related art. The grease composition for a ball joint according to the present invention contains a silicone oil as a base oil and an additive, and contains an amino-modified silicone and a modified polyolefin as the additive. The silicone oil preferably includes at least one of dimethyl silicone oil and phenyl-modified silicone oil.

The invention relates to the use of at least one compound, which has at least one sterically hindered amine or phenolic function, as an anti-corrosion additive in a lubricant composition for a propulsion system of an electric or hybrid vehicle, said lubricant composition comprising one or more amino and/or sulfur anti-wear additives. The invention also relates to the use of a lubricant composition comprising one or more compounds, which has at least one sterically hindered amine or phenolic function, as one or more anti-corrosion additives, further comprising one or more amino and/or sulfur anti-wear additives, for lubricating a propulsion system of an electric or hybrid vehicle, in particular for lubricating the electric motor and the power electronics of an electric or hybrid vehicle.

The present invention provides a refrigerating machine oil comprising a hydrocarbon-based base oil having a viscosity index of 120 or less, and the refrigerating machine oil being used with a 1-chloro-2,3,3,3-tetrafluoropropene refrigerant.

A method for utilizing a lubricating oil composition in which the content of a metal-based cleaning agent (X) having a base value of 100 mgKOH/g or less is 630 mass ppm or less in terms of metal atoms, and the content of sulfated ash is 1.5 mass % or less. The method includes measuring at least one physical property value among the capacitance and the dielectric constant of the lubricating oil composition while using the lubricating oil composition, and evaluating the progress of degradation of the lubricating oil composition.

A lubricating oil composition may be suitable for a refrigerator and have excellent thermal stability when used with a refrigerant using difluoromethane (R32), trifluoroiodomethane (CF.sub.3I), and at least one selected from saturated fluorinated hydrocarbon compounds (HFC) other than difluoromethane (R32). Such compositions may include: a base oil (A) with at least one selected from a polyoxyalkylene glycol, a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol or a monoether thereof and a polyvinyl ether, and a polyol ester; and an aliphatic epoxy compound (B), wherein the content of the aliphatic epoxy compound (B) is more than 2.0% by mass based on the total amount of the lubricating oil composition.

The present invention relates to a hydraulic fluid composition containing a base oil (A), an antioxidant (B) including an amine-based antioxidant (B1) and a phenol-based antioxidant (B2), and a succinimide-based compound (C), wherein the hydraulic fluid composition satisfies the following requirement (I); and is to be used for hydraulic equipment which is equipped with at least one of a wet type brake and a wet type clutch and which is selected from a construction machinery, a general industrial machinery, and a power generator, and in which a working pressure is 30 MPa or more. The hydraulic fluid composition is not only excellent in wear resistance and an effect for suppressing the sludge formation but also excellent in a braking performance or a clutch performance, even when used under a high-pressure condition. Requirement (I): A static friction coefficient (μ.sub.s) after 1,000 cycles, as measured in conformity with the SAE No. 2 test described in JCMAS P 047:2004, is 0.100 to 0.162.

The present invention provides a lubricant composition comprising a base oil of lubricating viscosity, wherein the base oil comprises an ether base stock of formula (A), where: R.sub.a and R.sub.b are aliphatic hydrocarbyl groups and may be the same or different; the lubricant composition further comprising at least one aminic anti-oxidant and at least one phenolic anti-oxidant. In some embodiments, the ether base stock has the formula (1), where: R.sub.1 R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are as defined herein. The lubricant composition may be used for lubricating a surface in an internal combustion engine as well as for improving the fuel economy performance and/or piston cleanliness performance of an engine and/or a vehicle, such as an automotive vehicle associated with an internal combustion engine. ##STR00001##

The present invention provides a thermal management system comprising a housing having an interior space; a heat-generating component disposed within the interior space; a heat exchanger; and a working fluid liquid disposed within the interior space wherein the heat-generating component is in contact with the working fluid. The working fluid comprises a Fischer-Tropsch derived base fluid; an antioxidant and anti-static additives. The system is constructed wherein a constant cyclical flow of working fluid is maintained across the heat-generating components, on to the heat exchanger and then back to the heat-generating component.

The present invention provides a method of thermal management of a heat-generating component comprising partially immersing a heat-generating component in a working fluid and transferring the heat from the heat-generating component using the working fluid in a constant cyclical flow of working fluid across the heat-generating components, on to a heat exchanger and then back to the heat-generating component.

A grease composition including: an ester base oil; and a thickener, in which the thickener contains diurea expressed by the following formula (1): R1-NHCONH-C6H4-CH2-C6H4-NHCONH-R2 (1), in which R1 and R2 each independently represents one of: (A) an alicyclic group A expressed by R3-C6H10- (R3 represents hydrogen, a 2-methyl group, a 3-methyl group, or a 4-methyl group); (B) an alkyl group B expressed by n-CmH2m+1 (m represents an integer of 6 to 10); and (C) an alkyl group C expressed by n-CmH2m+1 (m represents an integer of 16 to 20), and in which the diurea is arranged so that the alicyclic group A is 5 to 35 mol %, a total of the alicyclic group A and the alkyl group B is 55 to 95 mol %, and the remainder is the alkyl group C, based on a total of R1 and R2.