Lubricating composition comprising (i) base oil and (ii) a metal-free phosphonate compound having the general formula P(═O)(R.sup.1)(OR.sup.2)(OR.sup.3) wherein R.sup.1, R.sup.2 and R.sup.3 are the same or different and each independently selected from a straight chain or branched, saturated or unsaturated, C.sub.4-C.sub.22 alkyl group. The lubricating composition of the present invention provides improved engine durability, improved wear and friction reduction, improved fuel economy and excellent oxidative stability.

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.

A urea grease of the invention is prepared by applying shear at a shear rate of 10.sup.2 s.sup.−1 or more to a mixture solution of an amine mixture containing an alicyclic monoamine and a chain aliphatic monoamine, and a diisocyanate compound to cause a reaction in the mixture, in which the urea grease has Peak High32-64s of 1.5 or less and Level High32-64s of 10 or less according to an FAG method.

A polyalphaolefin composition is provided comprising trimers of C12 alpha-olefins and dimers of C14 alpha-olefins, where the ratio by weight of C12 trimer to C14 dimer is within a range of 4:1 by weight to 1:4 by weight, where the C12 trimer enriched polyalphaolefin has an average branching ratio <0.2 and the C14 dimer has an average branching ratio of >0.20, and where the average branching ratio for all C12 trimers and C14 dimers is between 0.19 and 0.26. The composition has a boiling point distribution where less than 30% by weight of the composition has a boiling point between 420° C. and 455° C., and the resulting base oil has a kinematic viscosity of about 3.3 to 4.7 cSt at 100° C.

The invention provides a grease composition, being a grease composition containing a base oil and, as a thickener a calcium complex soap, and being a grease composition using for the carboxylic acids forming the aforementioned calcium complex soap substituted or unsubstituted C18-22 straight-chain higher fatty acids, aromatic monocarboxylic aromatic acids having substituted or unsubstituted benzene rings and C2-4 straight-chain saturated lower fatty acids, wherein the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids include behenic acid and the amount of behenic acid used, as a mass ratio in terms of the total amount of the aforementioned substituted or unsubstituted C18-22 straight-chain higher fatty acids used, is from 25 mass % up to 70 mass %.

The invention relates to a lubricant comprising a diester of adipic acid with a tridecanol mixture which comprises 20 to 60% of at least triply branched tridecanols, 10 to 50% doubly branched tridecanols, and 5 to 30% singly branched and/or linear tridecanols, and where the percentages are determined by gas chromatography.

The invention provides a lubricating composition comprising an oil of lubricating viscosity and synergistic mixture of a functionalized ethylene-α-olefin copolymer, a poly(meth)acrylate block polymer having a substantially oil soluble block and a substantially oil insoluble block. The invention also provides a method of lubricating a mechanical device using such a lubricating composition.

The present invention relates to the use of a lubricating composition comprising: —at least one base oil; and—at least one monoester which is separate from the base oil and formed between a linear, saturated or unsaturated C.sub.8-C.sub.14 monocarboxylic acid, and a branched, saturated or unsaturated C.sub.4-C.sub.16 monoalcohol to reduce the fuel consumption of a vehicle fitted with a transmission member, in particular a gearbox and/or an axle, which is lubricated by means of said composition.

The present invention relates to drilling fluid comprising one or more linear internal olefin having from 15 to 18 carbon atoms and containing less than 25% branching based on the total amount of the linear internal olefin and a hydrogenated Fischer-Tropsch derived product.

The present invention relates to the use of a lubricating composition comprising: -at least one base oil; and -at least one monoester which is separate from the base oil and formed between a linear, saturated or unsaturated C.sub.8-C.sub.14 monocarboxylic acid, and a branched, saturated or unsaturated C.sub.4-C.sub.16 monoalcohol to reduce the fuel consumption of a vehicle fitted with a transmission member, in particular a gearbox and/or an axle, which is lubricated by means of said composition.