A composition obtained by reacting an O,O′-dialkyldithiophosphoric acid with a hydroxyalkyl acrylate or a hydroxyalkyl methacrylate, and reacting the product thereof with a dialkylphosphite provides good antiwear protection.

The invention provides a lubricant composition comprising an oil of lubricating viscosity and a protic acid salt of an N-hydrocarbyl-substituted gamma-(γ-) or delta-amino(thio)ester. The invention further relates to a method of lubricating a mechanical device with the lubricant 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.

The present disclosure relates to lubricating oil compositions, and in particular, lubricating oil compositions for slideway applications, additive compositions for the slideway lubricants, and methods of lubricating a machine part, such as a slideway with the lubricating oil compositions. In one aspect, the lubricating oil compositions have a composition that provides both good friction performance and good separability from metal working fluids at the same time.

The present disclosure relates to a lubricant composition comprising a lubricant, a first ionic liquid which is soluble in polyalphaolefin and a second ionic liquid which is insoluble in polyalphaolefin. By using the two different ionic liquids, the technical properties of the lubricant compositions can be improved.

The present invention relates to a lubricant composition, and more particularly to a lubricant composition, which has superior oxidation stability and friction characteristics even under harsh conditions of high temperature and high pressure and is thus suitable for use in hydraulic oil. The lubricant composition of the present invention includes a base oil, a liquid olefin copolymer, a phosphorothioate compound, and phosphonium phosphate.

A hydraulic lubricating oil composition is provided which contains a synergistic mixture of three phosphorous antiwear components in order to provide good thermal stability and good demulsibility to the lubricating oil composition.

Provided is a mixed grease containing a grease (A) prepared from a base oil (a1) and a thickening agent (a2) that is a lithium soap consisting of a lithium salt of a monovalent fatty acid, and a grease (B) prepared from a base oil (b1) and a thickening agent (b2) that is a lithium complex soap consisting of a lithium salt of a monovalent fatty acid and a lithium salt of a divalent fatty acid. The mixed grease has good wear resistance and load bearing properties and has excellent grease leakage preventing properties.

The present invention, in one aspect, provides a refrigerating machine oil including a lubricating base oil and a compound represented by the following formula (A): ##STR00001##
wherein R.sup.1 and R.sup.2 each independently represent a monovalent hydrocarbon group, and R.sup.3 and R.sup.4 each independently represent a hydrogen atom or an alkyl group, the refrigerating machine oil being used with a refrigerant including an unsaturated hydrofluorocarbon.

The present invention relates to a lubricating oil composition containing a mineral oil (A) containing 30% by mass or more of a bright stock (A1) on the basis of the total amount of the lubricating oil composition, wherein the lubricating oil composition further contains a synthetic oil (B) and a phosphoric acid ester (C), the content of the synthetic oil (B) is less than 70% by mass on the basis of the total amount of the lubricating oil composition, the content of the phosphoric acid ester (C) as expressed in terms of a phosphorus atom is 0.050 to 0.200% by mass on the basis of the total amount of the lubricating oil composition, and a viscosity index is 150 or more, thereby providing a lubricating oil composition having low temperature dependence and favorable lubricating characteristics even in the case of using the mineral oil containing a bright stock.