Provided are lubricant compositions comprising a base oil, a polyoxypropylene polymer, and a butyleneoxy based polyoxyalkylene polymer. The base oil, polyoxypropylene polymer and polyoxyalkylene polymer are soluble with one another.

The present disclosure provides a lubricating oil composition which is excellent in metal fatigue life, wear resistance and electrical insulating properties, even when the composition has a reduced viscosity. The lubricating oil composition according to the present disclosure comprises: (A) a lubricating base oil; (B) from 0.6 to 4.0% by weight, based on the total weight of the lubricating oil composition, of a polydiene having a number average molecular weight of from 500 to 3,000 and containing a functional group on at least one end thereof; and (C) at least one selected from a phosphorus-based anti-wear agent and a phosphorus-based extreme pressure agent, the at least one agent being contained in such an amount that the content of phosphorus is from 50 to 500 ppm by weight based on the total weight of the lubricating oil composition.

The present invention provides a refrigerating machine oil containing an ester base oil obtained from pentaerythritol and mixed fatty acids of a fatty acid having 8 carbon atoms and a fatty acid having 9 carbon atoms, wherein a ratio of a weight average molecular weight Mw to a number average molecular weight Mn, Mw/Mn, of the ester base oil is 1.06 to 1.20, and used with a mildly flammable hydrofluorocarbon refrigerant.

The present invention provides a refrigerating machine oil comprising: a base oil; a compound represented by the following formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent a monovalent hydrocarbon group, R.sup.3 represents a divalent hydrocarbon group and R.sup.4 represents a hydrogen atom or a monovalent hydrocarbon group; and an epoxy compound.

The present invention generally relates to lubricating oil compositions comprising a biobased base oil, methods of lubricating an engine with said lubricating oil compositions. Also disclosed is the use of said lubricating oil compositions in an engine.

The present invention relates to compounds according to formula (Ia) or formula (Ib);

##STR00001##

wherein each W is independently selected from the group consisting of H, F, Cl, Br, I and (CY.sub.2).sub.mCY.sub.3; each Y is independently selected from the group consisting of F, Cl, Br and I; each Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.pCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, (CW.sub.2).sub.pOH, polyalkylene glycol and polyolester; n is an integer from 2 to 49; m is an integer from 0 to 3; p is an integer from 0 to 9; the molecular weight average (M.sub.W) is ≤5500; and the polydispersity index is ≤1.45; compositions comprising these compounds and methods for their production.

A process for producing a borated polyalkenyl succinimide dispersant composition in which the boron is incorporated primarily as cyclic metaboric acid moieties and the equivalents of boron incorporated per equivalent of nitrogen in the succinimide carrier is greater than 2; in which process a slurry of orthoboric acid is added to a polyalkenyl succinimide to form a reaction mixture, which reaction mixture is then heated under conditions (at a temperature and pressure and for a time) sufficient to remove from the reaction mixture from about 0.8 to about 1.2 moles of water of reaction per mole of boric acid charged.

The present invention provides a refrigerating machine oil comprising, as a base oil, at least one oxygen-containing oil having a carbon/oxygen molar ratio of 2.5 or more and 5.8 or less, wherein the refrigerating machine oil is used with a refrigerant comprising 15% by mass or more of difluoromethane, 15% by mass or more of pentafluoroethane, 15% by mass or more of 2,3,3,3-tetrafluoropropene and 15% by mass or more of 1,1,1,2-tetrafluoroethane based on the total amount of the refrigerant.

The use of polyalkylenyl succinic anhydrides to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of berated dispersant, preferably in combination with polyalkylenyl succinic anhydrides, to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.