A grease composition includes a base oil, a thickener, and an additive. The base oil contains a synthetic oil. The thickener contains a compound having a urea group. The additive contains a phosphoric compound, a calcium-based compound, and a hydrocarbon-based wax. A hub unit includes the grease composition enclosed therein.

A low friction wear surface with a coefficient of friction in the superlubric regime including graphene and nanoparticles on the wear surface is provided, and methods of producing the low friction wear surface are also provided. A long lifetime wear-resistant surface including graphene exposed to hydrogen is provided, including methods of increasing the lifetime of graphene containing wear surfaces by providing hydrogen to the wear surface.

The disclosed technology relates to a lubricant composition for automotive gears, axles and bearings, the lubricant composition containing an oil of lubricating viscosity and an oil-soluble titanium compound in place of boron compounds, as well as a method of obtaining thermal stability performance in automotive gears, axles and bearings without the boron content that is typical, by lubricating such automotive gears, axles and bearings with a lubricant composition containing an oil-soluble titanium compound and an amine-containing phosphorus rainwear agent.

A sliding member includes: a base material; a coating layer formed on the base material and made of a resin composition including: a binder resin including polyamideimide; PTFE dispersed in the binder resin; and at least one of graphite and MoS.sub.2 dispersed in the binder resin; wherein a surface roughness of the coating layer after a sliding test is equal to or less than the surface roughness of the coating layer before the sliding test.

There is provided a lubricating oil composition which is excellent in the wear resistance and the oil film retention even when the viscosity of the composition is lowered. The lubricating oil composition comprises: a base oil (A); an imide compound (B); a calcium-based detergent (C); a polymer component (D); and a zinc dithiophosphate (E), wherein the imide compound (B) comprises at least one non-boron-modified succinic acid imide compound (Bx) selected from a succinic acid monoimide (B1x) represented by general formula (b-1) and a succinic acid bisimide (B2x) represented by general formula (b-2), and wherein the polymer compound (D) has a mass average molecular weight (Mw) of not less than 10,000 and not more than 50,000, and comprises at least one selected from an olefin polymer (D1) and a polymethacrylate (D2).

An aspect of the present invention relates to a lubricant composition containing at least: (A) 50 to 80 mass % of silicone oil represented by formula (1) below, and having a mass-average molecular weight of 900 to 4000, a ratio (C/Si ratio) of carbon to silicon of 3.03 or higher in the structure, and a viscosity index (VI) of 300 or higher; (B) 10 to 49 mass % of hydrocarbon-based lubricant; and (C) 1 to 10 mass % of antioxidant.

This is to provide an electrically-conductive lubricant having characteristics in combination that it shows liquid crystallinity in a wide temperature range, retains low dynamic friction coefficient, has electrical-conductivity, has almost no loss due to evaporation, decomposition and the like, has a clean appearance, and emits fluorescence, and can find deterioration or leakage immediately. This electrically-conductive lubricant comprises at least one kind of the compound (1) represented by the formula (1): ##STR00001##
12:8 wherein, R.sup.11 and R.sup.21 are the same or different from each other, and each is hydrogen or a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl), and R.sup.12, R.sup.13, R.sup.22 and R.sup.23 are the same or different from each other, and each is a group —OCH.sub.2CH.sub.2CH(R′)CH.sub.2CH.sub.2OR (R is a linear or branched C.sub.nH.sub.2n+1, 4≤n≤12, and R′ is methyl or ethyl)].

The invention provides a grease composition for a ball joint which has a low friction coefficient under a load from normal temperatures to high temperatures, a small difference between static friction and dynamic friction, and little change in the friction coefficient even after repeated operation. TO this end, the invention provides a grease composition for a ball joint comprising: (i) a polyisoprene rubber and/or (ii) a polyisoprene rubber viscous material; a specific aliphatic amide and/or a specific aliphatic bisamide; and a specific urea compound.

Provided is a lubricating oil composition for air compressors containing a polyalkylene glycol-containing base oil (A) and a rust-preventive agent (B), wherein the content of the polyalkylene glycol is 65.0% by mass or more based on the total amount of the composition. The lubricating oil composition is excellent in oxidation stability and also in rust prevention and storage stability. Also provided are an air compressor lubricating method and an air compressor using the lubricating oil composition.

An object of the present invention is to provide an ester-based lubricating base oil for a fluid bearing that has a high viscosity index and excellent evaporation resistance, hydrolytic stability, and low-temperature fluidity. The present invention relates to a lubricating base oil for a fluid bearing containing a compound represented by general formula (1): ##STR00001##
wherein R.sup.1 represents a linear C.sub.2-C.sub.16 alkyl group, m represents an integer of 2 to 10, and n represents an integer of 4 to 14.