A lubricating oil composition may be capable of satisfactorily exhibiting sludge prevention properties and wear resistance evaluated by scoring resistance and seizure resistance over a long period of time. Such a lubricating oil composition may contain: a base oil (A); a hindered phenol-based antioxidant (B); one or more imide compounds (C) selected from the group consisting of a monoimide compound (C1) and a bisimide compound (C2); and an extreme pressure agent (D), in which the hindered phenol-based antioxidant (B) is 2,6-di-tert-butylphenol, the monoimide compound (C1) is one or more selected from the group consisting of an alkenyl succinic monoimide compound and an alkyl succinic monoimide compound, and the bisimide compound (C2) is one or more selected from the group consisting of an alkenyl succinic bisimide compound and an alkyl succinic bisimide compound.

An aspect of the present invention provides a refrigerating machine oil containing a mixed base oil of a first hydrocarbon base oil having a kinematic viscosity at 40° C. of less than 6 mm.sup.2/s and a second hydrocarbon base oil having a kinematic viscosity at 40° C. of 6 mm.sup.2/s or more, wherein a (A)/(B) ratio is more than 1 and 1.5 or less, wherein (A) is a kinematic viscosity at 40° C. of the mixed base oil, and (B) is the kinematic viscosity at 40° C. of the first hydrocarbon base oil.

A lubricating composition for a transmission or gearbox including a mixture of products providing phosphorus to the fluids effective to achieve good adhesive wear and abrasive wear.

The invention relates to a grease composition including a base oil and a thickener that provides hydrophilic metal oxide particles and one or more amides which contain one or more unsaturated C—C bonds and/or at least one OH group. The hydrophilic metal oxide particles have a BET specific surface area of at least 10 m2/g and at least 80% of the hydrophilic metal oxide particles have a particle size in the range of from 5 nm to 900 μm. The amount of the thickener is in the range of from 0.1-40% by weight, based on the total weight of the grease composition. The invention further relates to methods for manufacturing the grease composition, and the use of the grease composition for lubricating bearings, gears and couplings.

The present disclosure relates to a lubricating fluid for an electric motor system and a method of lubricating gears and cooling a motor in an electric motor system. In particular, the disclosed technology relates to a lubricating fluid, for use in electric motor vehicle, comprising an oil of lubricating viscosity and at least one phosphorylated dispersant exhibiting increased resistivity after aging.

A lubricating oil composition for internal combustion engines of passenger and commercial four-wheeled vehicles is provided which can exhibit excellent fuel efficiency performance and wear resistance reliability. The lubricating oil composition includes a base oil and a complex polyester mixture. The base oil includes at least one of poly-α-olefin, an ester-based base oil, or a partially hydrogenated mineral oil. The complex polyester mixture includes a polyester obtained by condensing a polyhydric alcohol, a polycarboxylic acid, and a monohydric alcohol having an oxyalkylene group. The content of the complex polyester mixture is 0.01% by mass or more with respect to the total mass of the lubricating oil composition, the high-temperature shear viscosity (HTHS viscosity) at 150° C. is 1.0 mPa.Math.s to 2.6 mPa.Math.s, and the NOACK evaporation amount is 40% or less.

The disclosed technology relates to an automotive or industrial gear oil for automotive or industrial gears, as well as axles and bearings, the automotive or industrial gear oil containing an oil of lubricating viscosity, an optional phosphate and/or thiophosphate compound, a particular sulfurized olefin, and a metal thiophosphate compound, such as zinc dialkyldithiophosphate, as well as a method of improving automotive or industrial gear operating efficiency and temperature by lubricating such automotive or industrial gears with the automotive or industrial gear oil.

A water-based lubricating grease composition includes at least 40 wt % water; a salt-based thickener; a polymer-based thickener; and optionally, an inorganic solid-based thickener. A process for preparing the water-based lubricating grease composition may include blending a suitable amount of water with a salt-based thickener to provide a thickened water-based grease, wherein the salt-based thickener is obtained from contacting a base with a fat; and adding a polymer-based thickener to the thickened water-based grease.

A lubricating oil composition may have excellent long-term anti-foaming performance and detergency while blending a silicone-based anti-foaming agent. Such a lubricating oil composition may contain a base oil (A) and a silicone-based anti-foaming agent (B). A silicon atom content may be 50 ppb by mass to 4,000 ppb by mass, based on a total amount of the lubricating oil composition.

The invention relates to phosphorous-containing compounds useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.