Provided herein are estolide compositions having high oxidative stability, said compositions comprising at least one compound of formula:

##STR00001##

in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 1; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided herein are uses for the compositions and methods of preparing the same.

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.

Provided are a lubricating oil composition for internal combustion engine capable of preventing a deterioration of the combustion state of a spark-ignition internal combustion engine, specifically, a lubricating oil composition to be used for a spark-ignition internal combustion engine in which a total tension per piston of tensions applied to the piston ring is 100 N or less, the lubricating oil composition being a lubricating oil composition including a base oil, (A) a calcium-based detergent, at least one selected from (B1) a sodium-based additive and (B2) a magnesium-based additive, and (C) an ash-free sulfur-based additive in predetermined contents; a method for producing the lubricating oil composition; a spark-ignition internal combustion engine using the lubricating oil composition; and a method for lubricating the internal combustion engine.

Disclosed is a lubricating oil composition comprising an oil of lubricating viscosity and an oil soluble synergistic mixture of antioxidants, said mixture comprising: a) a hindered amine antioxidant according to formula (I)

##STR00001## wherein each R.sup.1 is independently selected from a substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; R.sup.2 is selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; each R.sup.3 is independently selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; each R.sup.4 is independently selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; n is an integer from 1 to 4; and m is an integer from 1 to 5; and b) a molybdenum succinimide complex.

The application provides a rolling bearing including a grease composition, the grease composition containing a base oil and a thickener, the base oil containing an aromatic ester-based base oil, and the thickener containing a urea-based thickener, where the grease composition has a storage elastic modulus at 25 C. of from 1200 to 3000 Pa as measured under conditions of a film thickness of 1 mm and a shear strain of 1% and has an oil separation amount at 80 C. of from 200 to 270 mm.sup.2/mg; a pivot assembly bearing apparatus including the rolling bearing; and a disk drive apparatus including the pivot assembly bearing apparatus.

Object

Objective is to provide a grease composition for a pivot assembly and a pivot assembly bearing filled with the grease composition, and to provide a bearing apparatus as well as a drive apparatus including the bearing apparatus, which is capable of suppressing adhesion of a volatilized component to a magnetic disk or the like even when the grease composition is volatilized by application of the grease composition and the bearing, thereby suppressing occurrence of read/write errors of an HDD.

Solution

Provided are: a grease composition for a pivot assembly bearing including an aromatic ester-based base oil and a thickener, the aromatic ester-based base oil containing an aromatic ester compound having an ester group *(CO)O as a substituent on a ring, where * is a bonding site to an aromatic ring, and having an alkyl group with a total of 8 or more carbon atoms bonded to an oxygen atom of the ester group; a pivot assembly bearing filled with the grease composition for pivot assembly bearing; a bearing apparatus including the pivot assembly bearing; and a disk drive apparatus equipped with the bearing apparatus.

The invention relates to lubricating compositions, processes of making such lubricating compositions, and method of using such lubricating compositions. The lubricating compositions of the present invention include a dispersant comprising a quaternary ammonium salt, a phosphorus-containing compound, a metal dialkyldithiophosphate, a derivative of a hydroxyl carbonyl compound and an amine and/or an alcohol. These compositions provide balanced deposit control and wear performance without causing any seal compatibility issues.

Lubricant compositions having at least one base oil composition and a friction-reducing composition comprising at one or more hydrocarbyl aromatics comprising a mono- or poly-functionalized aromatic moiety are described. Methods for making such compounds and methods of drilling using such lubricant compositions are also described.

A method for improving deposit control, while maintaining or improving demulsibility performance, in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil that has a particular phenate/carboxylate detergent mixture present in a particular amount in the formulated oil. A lubricating engine oil having a composition including a lubricating oil base stock as a major component; and a phenate/carboxylate detergent mixture as a minor component. The lubricating oils of this disclosure are useful in marine crankcase systems, in particular, marine system oil applications for two-stroke marine diesel engines.

Compounds [compounds (L)] comprising at least one monocyclic, polycyclic or polycondensed aromatic moiety [moiety (A*)], wherein: at least one carbon atom of moiety (A*) is substituted with a fluoropolyoxyalkene chain [chain (R.sub.f)], said chain (R.sub.f) comprising: a) a fluorocarbon segment having ether linkages in the main chain and b) at least one hydroxyl group and wherein: at least one other carbon atom of moiety (A*) is substituted with an electron-withdrawing group and mixtures thereof are herein disclosed. Disclosed are also a process for manufacturing compounds (L), a method for lubricating MRM comprising using compounds (L), a lubricant composition comprising one or more compounds (L) and a method for manufacturing a composition (C).