The invention provides lubricating composition comprising: an oil of lubricating viscosity, and an oxyalkylated hydrocarbyl phenol, wherein the oxyalkylated hydrocarbyl phenol is substituted with at least one aliphatic hydrocarbyl group of 40 to 96 carbon atoms, and wherein the oxyalkylated hydrocarbyl phenol is substantially free of aromatic hydrocarbyl groups. The invention further relates to a method of lubricating a mechanical device (such as an internal combustion engine) with the lubricating composition. The invention further relates to the use of the oxyalkylated hydrocarbyl phenol in the lubricating composition to a passenger car internal combustion engine at least one of (i) control of fuel economy, (ii) control of corrosion, (iii) cleanliness, and (iv) control of bore wear.

Sulfurized calcium phenate detergents having a reduced unsulfurized alkyl-substituted phenol content are made by: (A) providing, made from an unsulfurized alkyl-substituted phenol, a sulfurized calcium phenate detergent that, optionally, may have been further reacted with carbon dioxide; (B) adding to the detergent from 1 to 100 mass %, based on the mass of the detergent, of an organic solvent that has a boiling point of above 100 C. and below the boiling point of the unsulfurized alkyl-substituted phenol; and (C) removing the organic solvent from the detergent thereby to reduce the unsulfurized alkyl-substituted phenol content.

The invention provides a composition containing an oil of lubricating viscosity and an N-substituted malimide. The invention further relates to the use of the lubricating composition in an internal combustion engine.

A lubricant additive concentrate containing (i) dispersant that is the polybutenyl succinimide reaction product of a polyamine and polybutenyl succinic anhydride (PIBSA) derived from polybutene having a number average molecular weight (M.sub.n) of from about 1300 to about 2500 daltons and a terminal vinylidene content of at least about 50% and maleic anhydride via an ene maleation process; (ii) overbased magnesium colloidal detergent having a total base number (TBN) of from about 300 to about 900 mg KOH/g; and (iii) organic friction modifier selected from hydroxyalkyl alkyl amines of C.sub.14 to C.sub.24 hydrocarbons, at least one hydroxyalkyl alkyl ether amines of C.sub.13 to C.sub.24 hydrocarbons, at least one alkyl ester amine derived from triethanol amine having a C.sub.13 to C.sub.24 hydrocarbyl substituent, at least one non-basic, fatty acid amide, or a mixture thereof; wherein the combined mass % of dispersant (i) and overbased magnesium colloidal detergent (ii) in said concentrate is from about 15 to about 50 mass %: the mass ratio of (i):(ii) is from about 1:1 to about 6:1; and the concentrate contains from about 2 to about 10 mass % of organic friction modifier (iii); the remainder of the concentrate being composed of base oil and additives other than dispersant (i), overbased magnesium colloidal detergent (ii) and organic friction modifier (iii).

The invention provides a method of lubricating an internal combustion engine equipped with a centrifugal oil mist separator, wherein the lubricant contains 0.1 wt % to 8 wt % soot resulting from operation of the engine, and wherein the lubricant composition comprises an oil of lubricating viscosity, and 0.2 wt % to 3 wt % of a soot dispersing additive having a shear stability index of 0 to 25, wherein the soot dispersing additive comprises a block copolymer comprising (i) a vinyl aromatic monomer block and (ii), a conjugated diene olefin monomer block.

The invention provides a lubricant composition comprising an oil of lubricating viscosity and 0.01 wt % to 15 wt % of a (thio)phosphoric acid salt of an N-hydrocarbyl-substituted gamma-(-) or delta-amino(thio)ester. The invention further relates to a method of lubricating a mechanical device with the lubricant composition.

The invention provides a lubricant composition comprising an oil of lubricating viscosity and 0.01 wt % to 15 wt % of a protic acid salt of an N-hydrocarbyl-substituted gamma- (-) or delta- (-)amino(thio)ester. The invention further relates to a method of lubricating a mechanical device with the lubricant composition.

A lubricant additive concentrate containing 30 to 80 mass % oil of lubricating viscosity and from 20 to 70 mass % of additive; wherein from 30 to 90 mass % of the additive is (i) hybrid overbased colloidal detergent derived from sulfonate surfactant and hydroxybenzoate surfactant; and (ii) polyalkenyl succinimide dispersant derived from a polyalkene having a number average molecular weight (M.sub.n) of from 1300 to 2500 daltons, and wherein the mass ratio of polyalkenyl succinimide dispersant (ii) to hybrid overbased colloidal detergent (i) in the lubricant additive is from 25:1 to 1:1.

A metal detergent and a preparation method thereof and a lubricant oil containing the metal detergent. The metal detergent is sulfurized calcium alkyl phenolate, the method for preparing the metal detergent includes the following steps: a) mixing alkyl phenol, a calcium source and base oil to obtain a mixed solution; b) mixing the mixed solution, ethylene glycol and a sulfur source to carry out sulfurization reaction to obtain a sulfurization reaction solution; c) implementing carbonation reaction between the sulfurization reaction solution and CO.sub.2 to obtain a carbonation reaction solution; and d) extracting the carbonation reaction solution with a solvent, upon refining, to obtain sulfurized calcium alkyl phenolate; wherein the solvent includes solvent oil, water and oxygenous derivative of hydrocarbon. Experimental results show that the content of free alkyl phenol is below 1.5 wt % in the sulfurized calcium alkyl phenolate prepared using the preparation method provided by the present application.

A metal detergent and a preparation method thereof and a lubricant oil containing the metal detergent. The metal detergent is sulfurized calcium alkyl phenolate, the method for preparing the metal detergent includes the following steps: a) mixing alkyl phenol, a calcium source and base oil to obtain a mixed solution; b) mixing the mixed solution, ethylene glycol and a sulfur source to carry out sulfurization reaction to obtain a sulfurization reaction solution; c) implementing carbonation reaction between the sulfurization reaction solution and CO.sub.2 to obtain a carbonation reaction solution; and d) extracting the carbonation reaction solution with a solvent, upon refining, to obtain sulfurized calcium alkyl phenolate; wherein the solvent includes solvent oil, water and oxygenous derivative of hydrocarbon. Experimental results show that the content of free alkyl phenol is below 1.5 wt % in the sulfurized calcium alkyl phenolate prepared using the preparation method provided by the present application.