The present invention provides a working fluid composition for a refrigerating machine containing: a refrigerating machine oil containing: a first ester that is a polyol ester of dipentaerythritol and at least one fatty acid selected from fatty acids having 4 to 10 carbon atoms, and has a kinematic viscosity at 100 C. of 7.0 mm.sup.2/s or more; and a second ester that is a complex ester of a polyhydric alcohol containing at least one selected from neopentyl glycol, trimethylolpropane and pentaerythritol, a polybasic acid having 6 to 12 carbon atoms, and a monohydric alcohol having 4 to 18 carbon atoms or a fatty acid having 4 to 18 carbon atoms; and a refrigerant containing difluoromethane.

An ionic liquid composition having the following generic structural formula:

##STR00001##

wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are equivalent and selected from hydrocarbon groups containing at least three carbon atoms, and X.sup. is a phosphorus-containing anion, particularly an organophosphate, organophosphonate, or organophosphinate anion, or a thio-substituted analog thereof containing hydrocarbon groups with at least three carbon atoms. Also described are lubricant compositions comprising the above ionic liquid and a base oil, wherein the ionic liquid is dissolved in the base oil. Further described are methods for applying the ionic liquid or lubricant composition onto a mechanical device for which lubrication is beneficial, with resulting improvement in friction reduction, wear rate, and/or corrosion inhibition.

A lubricating composition suited to use in a marine diesel engine includes an oil of lubricating viscosity and an amino carboxylate compound of formula (I): NR.sup.1R.sup.2((CHR.sup.3).sub.xNR.sup.4).sub.n(CHR.sup.5).sub.2COY, where R.sup.1 and R.sup.2 are independently selected from (CHR.sup.6).sub.2COY, H, and C.sub.1C.sub.3 alkyl and wherein at least one of R.sup.1 and R.sup.2 is (CHR.sup.6).sub.2COY; or wherein NR.sup.1R.sup.2 is a cyclic structure; Y and Y are independently selected from OR.sup.4, NHR.sup.7, and N(R.sup.7).sub.2; each R.sup.7 is independently selected from C.sub.6-C.sub.12 alkyl and C.sub.6-C.sub.12 alkenyl; R.sup.3, R.sup.5 and R.sup.6 are independently selected from H and C.sub.1-C.sub.4 alkyl; R.sup.4 is selected from H, C.sub.1-C.sub.4 alkyl, and (CHR.sup.3).sub.xNH.sub.2; x is from 2 to 4; and n is at least 1, except where NR.sup.1R.sup.2 is a cyclic structure, where n is at least 0.

The present invention provides a refrigerating machine oil comprising a base oil; a sulfide compound; and an orthophosphoric acid ester, wherein a content of the sulfide compound is 0.01 to 2.0% by mass and a content of the orthophosphoric acid ester is 0.1 to 5.0% by mass, based on a total amount of the refrigerating machine oil, and the refrigerating machine oil having a kinematic viscosity at 40? C. of 3 to 500 mm.sup.2/s.

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 purpose of the present invention is to provide organometallic salt compositions that are useful as lubricant additives and/or in lubricant additive compositions to reduce friction and wear, and also have improved solubility in all four types of hydrocarbon base oils (Groups I-IV) at a variety of concentrations and under a variety of conditions. The organometallic salt composition is derived from at least one long chain monocarboxylic acid and a single metal in combination with at least one short or medium branched-chain monocarboxylic acid. The compositions are particularly useful in combination with activated complexes comprising a first metal component, a second metal component and particles comprising the first metal component.

A method for improving wear control in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and encapsulated microscale particles, as a minor component. The minor component contains no sulfur or phosphorus. The encapsulated microscale particles include an encapsulating material and a core material encapsulated by the encapsulating material. The core material includes at least one metal salt selected from a metal oxide, metal hydroxide, metal carbonate, or mixtures thereof. The encapsulating material is derived from a carboxylic acid selected from an aliphatic carboxylic acid, a cycloaliphatic carboxylic acid, an aromatic carboxylic acid, and mixtures thereof. The lubricating oils are useful in internal combustion engines.

An additive package for an internal combustion engine crankcase lubricating oil composition, which additive package comprises or is made by admixing: (A) 5-99.4 mass % based on the mass of the additive package, of a diluent oil of lubricating viscosity; and (B) the following additives: (B1) 0.1-10 mass % of a polymeric friction modifier, on an active matter basis, based on the mass of the additive package, which polymeric friction modifier is the reaction product of (a) a functionalised polyolefin, (b) a polyether, (c) a polyol, and (d) a monocarboxylic acid chain terminating group (B2) 0.5 to 10 mass % on an active matter basis, based on the mass of the additive package of one or more ashless organic friction modifiers that include a polar terminal group covalently bonded to a monomeric oleophilic hydrocarbon chain.

A composition including one or more monomethyl ester compounds represented by the formula:

##STR00001##

R.sub.1 is a monomethyl branched C.sub.15 to C.sub.19 alkyl group and R.sub.2 is an unsubstituted C.sub.2 to C.sub.30 linear alkyl group. The composition has a viscosity (Kv.sub.100) from 1 cSt to 10 cSt at 100 C. as determined by ASTM D445, a viscosity index (VI) from 100 to 300 as determined by ASTM D2270, a pour point from 0 C. to 50 C. as determined by ASTM D97, and a Noack volatility of no greater than 50 percent as determined by ASTM D5800. A process for producing the composition, a lubricating oil base stock and lubricating oil containing the composition, and a method for improving one or more of cold flow properties, thermal and oxidative stability, solubility and dispersancy of polar additives, deposit control and traction control in a lubricating oil by using as the lubricating oil a formulated oil containing the composition.

An ionic liquid composition having the following generic structural formula: ##STR00001##
wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are equivalent and selected from hydrocarbon groups containing at least three carbon atoms, and X.sup. is a phosphorus-containing anion, particularly an organophosphate, organophosphonate, or organophosphinate anion, or a thio-substituted analog thereof containing hydrocarbon groups with at least three carbon atoms. Also described are lubricant compositions comprising the above ionic liquid and a base oil, wherein the ionic liquid is dissolved in the base oil. Further described are methods for applying the ionic liquid or lubricant composition onto a mechanical device for which lubrication is beneficial, with resulting improvement in friction reduction, wear rate, and/or corrosion inhibition.