Defoaming agents comprising a silicone oil and silica particulates, lubricating oil compositions comprising the defoaming agent, methods of lubrication using a lubricating oil composition comprising the defoaming agent, and methods of reducing the foaming tendency/stability and/or improving the air release rates of non-aqueous fluids, such as lubricant oils, are provided.

The present invention provides a lubricating oil composition comprising: (a) a major amount of a lubricating oil, (a) a diarylamine antioxidant, and (b) an amidine compound of Formula (I),

##STR00001## wherein R.sub.1 is hydrogen, an alkyl or an aromatic group containing 1-30 carbon atoms; x is from 1 to 5; Y is an optional linking alkyl group; Z is carbon or nitrogen; and R.sub.2 is hydrogen or alkyl groups containing 1-30 carbon atoms.

Also provided is a method for lubricating an engine comprising lubricating the engine with said lubricating oil composition.

Provided herein are compositions comprising at least one estolide 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 are uses of the compositions described herein.

A lubricant composition comprises as a lubricant base, an oil soluble polyalkylene glycol suitable for use as a lubricant in an industrial oil, grease or metal working fluid; and an additive comprising (1) alkylated phenyl--naphthylamine; and (2) 2,2,4-trialkyl-1,2-dihydroquinoline.

The invention has an object of providing ethylene/-olefin copolymers having high randomness and a small number of double bonds in the copolymers. The ethylene/-olefin copolymers of the invention are obtained by copolymerizing ethylene and an -olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst which includes a bridged metallocene compound (A) represented by the formula [I], and at least one compound (B) selected from organometallic compounds (B-1), organoaluminum oxy compounds (B-2) and compounds (B-3) capable of reacting with the bridged metallocene compound (A) to form an ion pair, and have a specific weight average molecular weight, a specific molecular weight distribution, a specific glass transition point and a specific value B.

##STR00001##

An object of the present invention is to provide a lubricant which has excellent lubrication performance and is able to exhibit excellent lubrication performance even when under extreme pressure conditions. The present invention relates to a complex polyester composition containing polyester obtained by condensing polyhydric alcohol having at least two hydroxyl groups, a dicarboxylic acid having 44 carbon atoms, and monohydric alcohol. Further, the present invention relates to a lubricant composition containing the complex polyester composition, and a lubricant and a production method for a complex polyester composition.

A lubricant composition comprising (a) an oil of lubricating viscosity; (b) a (meth)-acrylate-containing polymer comprising a multiplicity of arms containing at least 20 carbon atoms, said arms being attached to a multivalent organic moiety; and (c) an ethylene/olefin copolymer having a weight average molecular weight of about 10,000 to about 250,000, wherein the copolymer comprises about 40 to about 70 weight percent polymerized ethylene monomers and optionally further comprises polymerized propylene monomers; exhibits good viscometric and antiwear properties.

The present invention provides a hydraulic oil composition comprising: a lubricating base oil having a kinematic viscosity at 40 C. of 15 to 50 mm.sup.2/s; and 1 to 40% by mass, based on a total amount of the hydraulic oil composition, of a polymethacrylate having a number-average molecular weight of 48000 or lower, the hydraulic oil composition having a viscosity index of 150 or higher, and a ratio (A/B) at 60 to 80 C. of (A) a kinematic viscosity (unit: mm.sup.2/s) to (B) a shear viscosity (unit: mPa.Math.s, shear condition: 10.sup.6/s) of 1.3 or lower.

A lubricating composition comprises an amide and at least one additive. The amide is the reaction product of a secondary, branched amine and a carboxylic acid. The carboxylic acid may be a monocarboxylic acid or a dicarboxylic acid, including dimer acid. The amide is hydrolytically stable, and may be used to increase the hydrolytic stability of the lubricant composition. Alternatively, the amide may be used to increase the additive solubility or detergency of the lubricant composition.

Corrosion inhibiting hydraulic fluid additives, kits, and methods are disclosed. The hydraulic fluid additive may be adapted for use with brake fluid in vehicular brake systems. The kits may include an additive, a hydraulic fluid tester, and/or correlated information on test results and hydraulic fluid service actions.