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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To provide a grease composition for a tapered roller bearing having superior bearing lifetime under a condition of high temperature and a condition of high load, and a tapered roller bearing in which the grease composition for the tapered roller bearing is filled. A tapered roller bearing 11 includes an inner ring 12 having a raceway surface 12a, an outer ring 13 having a raceway surface 13a and a plurality of tapered rollers 14, and a flange part of the inner ring 12 gets into sliding contact with the tapered rollers 14. Grease 16 is filled around the tapered rollers 14. The grease 16 includes a base oil, a thickener and an additive. A frequency in which a storage modulus, which varies depending on frequency, of the grease 16 becomes minimum is equal to 7 Hz or more.

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

The present invention relates to a composition for cooling a propulsion system of an electric or hybrid vehicle, comprising: (i) at least one base oil, or at least one hydrocarbon-based fluid with a boiling point of greater than or equal to 50° C.; and (ii) at least one fire retardant corresponding to formula (I)
R.sub.F-L-R.sub.H  (I) in which R.sub.F is a perfluorinated or partially fluorinated group, R.sub.H is a hydrocarbon-based group, and L is a linker, said fire retardant of formula (I) being at least partially in an encapsulated form. The invention also relates to the use of at least one fire retardant of formula (I) which is at least partially in an encapsulated form in a composition for cooling a propulsion system of an electric or hybrid vehicle, including at least one battery, to give it ignition-resistance properties. Finally, the invention relates to a process for cooling and fire-protecting a battery of a propulsion system of an electric or hybrid vehicle, comprising at least one step of placing at least one battery, in particular a lithium-ion or nickel-cadmium battery, in contact with a composition according to the invention.

A lubricating oil composition for hydraulic oils including 10 to 99% by mass of a lubricant base oil (A) with 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 (B) of ethylene and α-olefin prepared using a specific catalyst, wherein the total amount of (A) and (B) is 100% by mass, and having a kinematic viscosity at 100° C. of 10 to 300 mm.sup.2/s.

A refrigeration apparatus includes a heat source unit, a utilization unit, and a liquid refrigerant pipe and gas refrigerant pipe. The utilization unit has utilization unit internal pipelines. The liquid refrigerant pipe and the gas refrigerant pipe connect the heat source unit and the utilization unit internal pipelines. A refrigerant circulates through the heat source unit, the utilization unit, the liquid refrigerant pipe, and the gas refrigerant pipe. The refrigerant contains a compound represented by a molecular formula having one or more carbon-carbon unsaturated bonds. A disproportionation inhibitor for reducing a disproportionation reaction of the refrigerant is applied to at least a part of inner surfaces of the liquid refrigerant pipe, the gas refrigerant pipe, and the utilization unit internal pipelines.

A lubricating oil composition for automobile gears, including a lubricant base oil and a liquid random copolymer of ethylene and α-olefin(s), the liquid random copolymer being produced using a specific catalyst, wherein the lubricating oil composition has a kinematic viscosity at 100° C. of 7 to 30 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 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 having 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.

The present invention provides a lubricating oil composition comprising a polymer for improving viscosity, the composition suppressing viscosity increase in low temperature and having an excellent low-temperature property, and having low viscosity decrease caused by shearing. The present invention is a lubricating oil composition containing from 30 to 90% by weight of a liquid random copolymer (A) of ethylene and α-olefin produced by a specific method, and 10 to 70% by weight of a lubricating oil base consisting of one or more components selected from specific synthetic oil (B) or mineral oil (C) (note that the sum total of the components (A), (B) and (C) is 100% by weight).

A grease composition may be used for speed reducers and speed increasers, being excellent in both torque transmission efficiency and leak prevention performance. The grease composition may contain a base oil (A) and a urea-based thickener (B), which is used for speed reducers and speed increasers, wherein the particles containing the urea-based thickener (B) in the grease composition satisfy the following requirement (I). Requirement (I): the area-based arithmetic average particle diameter of the particles is 2.0 μm or less, as measured by a laser diffraction/scattering method.

Provided are: a lubricant base oil capable of achieving both a high traction coefficient and an excellent low-temperature fluidity at a higher level and having a high flash point, which contains a ring-containing compound having at least (i) a crosslinked bicyclic ring where two rings are bonded while sharing 3 or more carbon atoms, and (ii) an acyloxy group or a hydrocarbyloxycarbonyl group each containing a branched hydrocarbon group with a main chain having 4 or more carbon atoms, a lubricating oil composition containing the lubricant base oil, and a continuously variable transmission using the lubricating oil composition.