The present invention provides a wax isomerized oil, wherein a content of a hydrocarbon compound having an even number of carbon atoms, as determined from a chromatogram obtained by mass spectrometry, is more than 50% by mass based on a total amount of the wax isomerized oil.

A lubricating oil composition including: a lubricating base oil; (A) a first defoaming agent, the first defoaming agent being (A1) a first polymer, or (A2) a second polymer, or any combination thereof; and (B) a second defoaming agent, the second defoaming agent being a silicone defoaming agent, the (A1) first polymer including: a first polymer chain including a polysiloxane structure, the polysiloxane structure having a polymerization degree of 5 to 2000 and being represented by the following general formula (1); and a second polymer chain bonded with the first polymer chain, the second polymer chain including a repeating unit represented by the following general formula (2), the (A2) second polymer being a copolymer of a first monomer component and a second monomer component, the first monomer component represented by the general formula (7) or (8), the second monomer component represented by the general formula (9).

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Provided are: a lubricating oil composition for transmissions having a long fatigue life and a low viscosity, which contains a base oil and an olefin copolymer and in which the mass-average molecular weight of the olefin copolymer is 5,000 or more and 30,000 or less, the hydrodynamic radius of the olefin copolymer is 1.00 nm or more and 5.00 nm or less, and the content of the olefin copolymer based on the total amount of the composition is 1.0% by mass or more and 8.0% by mass or less; and a production method for the composition, a lubricating method using a lubricating oil composition for transmissions, and a transmission.

In a fluid bearing lubricating oil, a viscosity index improver including polymethacrylate is added to an ester oil-based base oil.

A sliding material composition comprising a polymer component comprising (A) a high-density polyethylene and (B) an olefin block copolymer; and (C) a silane coupling agent; wherein the Si content is 0.1 to 15% by mass based on the mass of the entire sliding material composition. The sliding material composition has the same level of slidability as a resin to which particles are added.

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.

A lubricating composition comprises an oil of lubricating viscosity, a metal-free pre-ceramic polymer and one or more co-additives. The metal-free pre-ceramic polymer comprises a plurality of repeat units which do not contain oxygen. The pre-ceramic polymers provide the lubricating oil composition with antiwear properties. Also described is a method of lubricating an internal combustion engine and the use of a lubricating oil composition containing a pre-ceramic polymers to inhibit wear in an internal combustion engine.

A lubricating oil composition for automobile transmissions including a lubricant base oil, and a liquid random copolymer of ethylene and α-olefin, the liquid random copolymer being produced using a specific catalyst, wherein the lubricating oil composition has a kinematic viscosity at 100° C. of 4.0 to 7.5 mm.sup.2/s, and a Brookfield viscosity at −40° C. of 20,000 mPa.Math.s or less, and wherein the lubricant base oil consists of a mineral oil with a kinematic viscosity at 100° C. of 2 to 10 mm.sup.2/s, a viscosity index of 105 or more, and a pour point of −10° C. or lower, and/or a synthetic oil with a kinematic viscosity at 100° C. of 1 to 10 mm.sup.2/s, a viscosity index of 120 or more, and a pour point of −30° C. or lower.

A lubricating oil composition for compressor oils, including 10 to 99% by mass of a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 14 mm.sup.2/s, a viscosity index of 100 or more, and a pour point of 0° C. or lower, and 90 to 1% by mass of a liquid random copolymer ethylene-α-olefin copolymer (B) of ethylene and α-olefin, the liquid random copolymer ethylene-α-olefin copolymer (B) being prepared by means of a specific catalyst (where the total amount of (A) and (B) is 100% by mass), the lubricating oil composition for compressor oils having a kinematic viscosity at 40° C. of 10 to 300 mm.sup.2/s.

A lubricating oil composition for internal combustion engines, including a lubricant base oil and 3% by mass or more, but less than 40% by mass of a liquid random copolymer of ethylene and an α-olefin, the liquid random copolymer being produced using a specific catalyst, wherein the lubricating oil composition has a kinematic viscosity at 100° C. of 6.9 mm.sup.2/s or more, but less than 12.5 mm.sup.2/s, and wherein the lubricant base oil consists of a mineral oil having a kinematic viscosity at 100° C. of 2 to 7 mm.sup.2/s, a viscosity index of 105 or more and a pour point of −10° C. or lower, and/or a synthetic oil having a kinematic viscosity at 100° C. of 1 to 7 mm.sup.2/s, a viscosity index of 120 or more and a pour point of −30° C. or lower.