[Problem] An ester compound having low viscosity, excellent fluidity even at low temperatures, and a high viscosity index; and a lubricating oil base oil containing said compound are provided. [Solution] The present invention provides an ester compound indicated by formula (I). Formula (I) (in formula (I), R.sub.1 is a hydrocarbon group having 1 to 35 carbon atoms and at least one hydrogen in the hydrocarbon group may be independently substituted with a group indicated by formula (II)). Formula (II) (in formula (II), R.sub.2 is a linear alkyl having 1 to 30 carbon atoms or a branched alkyl having 3 to 30 carbon atoms.)

Provided are a lubricating oil composition which contains a base oil (A) containing an ester-based oil (Al), and a polymer (B) having a constituent unit (b) derived from an alkyl (meth)acrylate, wherein the content of the polymer (B) is 0.1 to 10% by mass based on the total amount of the lubricating oil composition, the lubricating oil composition has a viscosity index of 350 or more, the lubricating oil composition has a BF viscosity at −40° C. of 4000mPa.Math.s or less, and the lubricating oil composition is used for an impregnated bearing, and an impregnated bearing impregnated with the lubricating oil composition. The lubricating oil composition has excellent lubricity in use in a wide temperature environment from a low temperature region to a high temperature region, is capable of maintaining excellent infiltration property even in an environment in which a temperature change between a low temperature and a high temperature is severe, and is suitable for use in an impregnated bearing.

A lubricant additive may be synthesized by forming a nanohybrid of a transition metal dichalcogenide and a metal borate, forming a base oil, and then dispersing the transition metal dichalcogenide into the base oil. An exemplary nanohybrid may be synthesized by forming a first solution by adding a borax solution to an aqueous solution of a metal source, forming a second solution by adding ethanol to the first solution, forming a mixture by mixing the transition metal dichalcogenide with the second solution, and heating the mixture at a temperature of 180° C. to 230° C. and a pressure of 5 to 20 bar under a nitrogen atmosphere.

The present invention generally relates to lubricating oil compositions useful for reducing NOACK volatility in finished lubricating oils of an internal combustion engine. Also disclosed is a method for reducing NOACK volatility in finished lubricating oils in said engine.

A magnetorheological fluid is provided having a reduced coefficient of friction and favorable settling characteristics. The fluid contains magnetically responsive particles, a carrier fluid, and an amine oleate salt.

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.

Described herein are methods of stabilizing the beta hydrogen of glycerol based esters by the insertion of alkoxy groups to significantly improve the thermal, oxidative, and hydrolytic stability of the ester and allow for controlling the molar density of esters bonds in the lubricants to maximize hydrolytic stability while maintaining biodegradability and further improving performance properties.

A comb polymer can be used for reducing a Noack evaporation loss of a lubricant composition, especially of an engine oil composition. Application of the comb polymer to the lubricant composition can bring about the desired reduction. The comb polymer can include specified amounts of macromonomer and alkyl acrylates. Resulting lubricant compositions can include the comb polymer.

A lubricating grease composition, and more specifically, to a lubricating grease composition which, when used with an article clamping device, such as a chuck, produces excellent lubricating properties whilst remaining strongly adhered to metal parts in the clamping mechanism of the device and showing enhanced chemical and physical resistance to fluids such as cutting fluids with which they come into contact.

The invention relates to a lubricating oil composition and a refrigerant composition containing a polyalkylene glycol having a terpenoid end group, such as a farnesol end group.