A lubricating oil composition which contains a base oil and a fluorine compound and may have improved cooling performance. The base oil may contain a mineral oil. The base oil may have a kinematic viscosity in a range of from 1 to 25 mm.sup.2/s at 40° C. The content of the fluorine compound may be in a range of from 3 to 30% by weight based on the total amount of the composition.

Disclosed is a method of lubricating a gas engine using a lubricant including at least one mineral base oil and at least one ester selected from among the polyol esters. The composition includes at least 50% by weight of mineral base oil and at least 5% by weight of polyol ester relative to the total weight of the lubricant composition.

Compositions, systems, and methods for introducing lubricants, and additives, that are designed to work with environmentally friendly refrigerants into vehicle heat management systems including passenger compartment air conditioning (A/C) systems are disclosed. Methods for charging lubricants and specific additives using environmentally desirable (low GWP) refrigerant or refrigerant blend compositions into an environmentally friendly system, such as a system that uses HFO-1234yf, are also disclosed.

To provide a lubricant solution capable of forming a uniform coating film by using a solvent composition which has a small impact on the global environment and which is excellent in solubility of the fluorinated ether compound, and a method for producing a substrate provided with a lubricant coating film. A lubricant solution comprising a solvent composition which comprises a HCFO and at least one member selected from the group consisting of 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorohexane, 1,1,1,2,2,3,3,4,4,5,5,6,6-tridecafluorooctane, nonafluorobutyl methyl ether, nonafluorobutyl ethyl ether and 3-methoxy-4-trifluoromethyl-1,1,1,2,2,3,4,5,5,5-decafluoropentane, and a fluorinated ether compound which is a fluorinated ether compound having a perfluoropolyether chain and CF.sub.3 groups at both terminals, wherein the perfluoropolyether chain does not have a branched structure.

The present invention aims to provide a viscosity index improver composition and a lubricating oil composition having a low HTHS viscosity at 100° C., an excellent shear stability, and an excellent low temperature viscosity. The present invention relates to, for example, a viscosity index improver composition (C), containing: a copolymer (A) containing a polyolefin-based monomer (a) represented by the following formula (1) as a constituent monomer; a copolymer (B) containing a (meth)acrylic acid alkyl ester (c) having a C12-C15 straight-chain or branched alkyl group and a (meth)acrylic acid alkyl ester (d) having a C16-C20 straight-chain or branched alkyl group as constituent monomers; and a base oil, wherein a weight average molecular weight ratio {(A)/(B)} of the copolymer (A) to the copolymer (B) is 2 to 55, and a weight ratio (A/B) of the copolymer (A) to the copolymer (B) constituting the viscosity index improver composition (C) is 5 to 100:

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The present invention relates to compositions comprising at least one (per)fluoropolyether base oil and at least one polymer obtained by the copolymerization of (per)fluoropolyether (PFPE), tetrafluoroethylene (TFE) and at least one non-homopolymerizable olefin.

The present invention relates to compounds according to formula (Ia) or formula (Ib); ##STR00001##
wherein each W is independently selected from the group consisting of H, F, Cl, Br, I and (CY.sub.2).sub.mCY.sub.3; each Y is independently selected from the group consisting of F, Cl, Br and I; each Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.pCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, (CW.sub.2).sub.pOH, polyalkylene glycol and polyolester; n is an integer from 2 to 49; m is an integer from 0 to 3; p is an integer from 0 to 9; the molecular weight average (M.sub.W) is ≤5500; and the polydispersity index is ≤1.45; compositions comprising these compounds and methods for their production.

A working fluid composition for a refrigerating machine, containing: a refrigerant containing trifluoroiodomethane; and a refrigerating machine oil containing a complex ester synthesized from a polyhydric alcohol, a polybasic acid, and at least one selected from a monohydric alcohol and a monocarboxylic fatty acid.

A hydrocarbon fluid is disclosed that has a pour point of at most −30° C., as measured by ASTM D5950, and that comprises at least 99 wt % of naphthenes and paraffins, based on the total weight of the hydrocarbon fluid, wherein the weight ratio of naphthenes to paraffins is at least 1, as measured by GC-MS, and wherein the paraffins consist essentially of isoparaffins, as determined by GC-FID. In addition, preferred uses of said hydrocarbon fluid are disclosed.

A lubricant including an ionic liquid including a conjugate base and a conjugate acid, wherein the conjugate acid is represented by General Formula (A) below, and wherein a pKa of an acid that is a source of the conjugate base in acetonitrile is 10 or less,

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where, in General Formula (A), R is a group including a straight-chain hydrocarbon group having 6 or greater carbon atoms, and R.sub.1 and R.sub.2 are each independently a hydrocarbon group.