The present invention provides a refrigerating machine oil comprising: a lubricating base oil; and 40 mass % or less of a polymer, based on a total amount of the refrigerating machine oil, the polymer having a structural unit represented by the following formula (I) and a weight average molecular weight of from 500 to 100000. ##STR00001## [In formula (I), R.sup.a, R.sup.b and R.sup.c each independently represents a hydrogen atom or a hydrocarbon group, and R.sup.d represents an oxygen-containing organic group or a C.sub.1-18 hydrocarbon group.]

Provided is a grease composition including a thickener and a base oil, in which the thickener is a urea compound represented by formula (1)
R1-NHCONHR2-NHCONHR3(1)
wherein R2 represents a divalent C.sub.6-15 aromatic hydrocarbon group, and R1 and R3 may be the same or different and each represent an C.sub.8-22 alkyl group, a cyclohexyl group, or an C.sub.6-12 aryl group, and as the base oil, one or more types of a compound represented by formula (2) are contained at 40% by mass or more relative to a total mass of the base oil, wherein R4 and R5 may be the same or different and each represent a linear or branched C.sub.10-26 alkyl group, where m and n are real numbers being 0 or more which satisfy m+n=2.

A lubricant composition is provided which comprises a base oil and hydroxytyrosol and/or esters thereof. Also provided is a lubricant composition in which the esters have a solubility in the base oil at 25 C. of at least 0.1 g/l. Further provided is a lubricant composition in which the esters are at least partly carboxylic acid esters comprising esters of hydroxytyrosol and C.sub.2-10 carboxylic acids.

The invention provides a lubricant composition for an eccentric oscillating planetary gear type speed reducer comprising the following components (a) to (d): (a) a base oil containing a synthetic oil; (b) at least one calcium salt selected from the group consisting of calcium salts of petroleum sulfonic acids, calcium salts of alkyl aromatic sulfonic acids, calcium salts of salicylates, calcium salts of phenates, calcium salts of oxidized waxes, overbased calcium salts of petroleum sulfonic acids, overbased calcium salts of alkyl aromatic sulfonic acids, overbased calcium salts of salicylates, overbased calcium salts of phenates, and overbased calcium salts of oxidized waxes; (c) an antioxidant; and (d) a glycerin fatty acid ester.

A lubricating base stock comprising an alkyl aromatic, a blend of additives, a blend of oil soluble polyalkylene glycols and a blend of polyolefins. In the lubricating base stock, the blend of polyolefins comprises at least one metallocene polyolefin.

The invention provides a grease composition used for lubricating a mechanical part having a steel portion to be lubricated which performs a rolling motion and a rolling and sliding motion, containing a base oil, a thickener and an additive, wherein the additive includes at least one compound selected from the group consisting of polyethylene wax, oxidized polyethylene wax, polypropylene wax, montan wax and amide wax.

This disclosure relates to cold cranking simulator viscosity (CCSV) boosting base stocks that allow flexibility for engine oil formulations to meet both high and low temperature viscosity requirements while maximizing fuel efficiency. The CCSV-boosting base stocks can include C28-C60 hydrocarbon materials, linear esters, tertiary amides, dialkyl carbonates, aromatic alcohols, and aromatic ethers. This disclosure also relates to lubricating oil formulations containing the CCSV-boosting base stocks, and a method for improving fuel efficiency in an engine by using as engine oil a lubricating oil formulation containing one or more of the CCSV-boosting base stocks.

This disclosure relates to cold cranking simulator viscosity (CCSV) boosting base stocks that allow flexibility for engine oil formulations to meet both high and low temperature viscosity requirements while maximizing fuel efficiency. The CCSV-boosting base stocks can include C28-C60 hydrocarbon materials, linear esters, tertiary amides, dialkyl carbonates, aromatic alcohols, and aromatic ethers. This disclosure also relates to lubricating oil formulations containing the CCSV-boosting base stocks, and a method for determining the CCSV-boosting efficacy of a base stock.

The present disclosure relates to surfactants formed from sulfonation of aromatic ethers. The example surfactant composition may include a sulfonated aromatic ether. The sulfonated aromatic ether may include an aromatic ring with substituents comprising an ether group and a sulfonic acid group or a salt of the sulfonic acid group. The ether group may be represented by the following formula:

##STR00001##

wherein R.sub.1 is a linear or branched alkyl group having from 1 carbon atom to 20 carbon atoms; wherein each R.sub.2 is individually a hydrogen or an alkyl group having from 1 carbon atom to 4 carbon atoms; and wherein n is a value from 0 to 8.

To provide a composition for a heat cycle system having favorable lubricating properties and comprising a working fluid for heat cycle which has a low global warming potential and which can replace R410A and a heat cycle system employing the composition. A composition for a heat cycle system comprising a working fluid for heat cycle containing trifluoroethylene, and a refrigerant oil (for example, an ester refrigerant oil, an ether refrigerant oil, a polyglycol refrigerant oil or a hydrocarbon refrigerant oil), and a heat cycle system employing the composition for a heat cycle system.