Use of a guanidinium-based ionic liquid as detergent in a lubricant composition, notably for lubricating marine engines. A lubricant composition including a guanidinium-based ionic liquid.

Use of a guanidinium-based ionic liquid as detergent in a lubricant composition, notably for lubricating marine engines. A lubricant composition including a guanidinium-based ionic liquid.

Disclosed is a method for maintaining emulsion stability in a hybrid engine. The method involves lubricating and operating the hybrid engine with a lubricating oil composition having a major amount of an oil of lubricating viscosity; minor amount of a magnesium containing detergent, and a minor amount of a borated dispersant.

Disclosed is a method for maintaining emulsion stability in a hybrid engine. The method involves lubricating and operating the hybrid engine with a lubricating oil composition having a major amount of an oil of lubricating viscosity; minor amount of a magnesium containing detergent, and a minor amount of a borated dispersant.

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).

Compositions comprising a) a metal detergent and b) an acid comprising at least one hydrocarbyl-substituted carboxylic acid. The metal detergent comprises at least one alkali metal, alkaline earth metal, or combinations thereof. The weight ratio of the metal detergent a) to the acid b) ranges from 50:1 to 1:10, or 25:1 to 1:10, or 10:1 to 1:10, or 5:1 to 1:7, or 2:1 to 1:3. The compositions may be added to industrial coating or lubricant compositions to reduce corrosion of metal components.

This invention provides a water-glycol hydraulic fluid comprises from 0.2 to 0.6% by mass of a dimer acid as a fatty acid lubricant, and more than 0.10% by mass and 0.20% by mass or less of a phosphoric acid ester of Formula (1), wherein the sum of the dimer acid and the phosphoric acid ester is more than 0.35% by mass wherein R.sub.1 and R.sub.2 may be the same or different, each representing a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, R.sub.3 represents a hydrocarbon group having from 1 to 20 carbon atoms, R.sub.4 represents a hydrogen atom or a hydrocarbon group having from 1 to 30 carbon atoms, and X.sub.1, X.sub.2, X.sub.3 and X.sub.4 may be the same or different, each representing an oxygen atom or a sulfur atom.

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The use of polyalkylenyl succinic anhydrides to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of berated dispersant, preferably in combination with polyalkylenyl succinic anhydrides, to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

A method of reducing the incidence of deposits on the pistons of a 4-stroke marine diesel engine during operation of the engine when it is fuelled with a marine residual fuel meeting the ISO 8217 2017 fuel standard for marine residual fuels and having a sulphur content of more than 0.1% and less than 0.5% by mass. The method includes the step of lubricating the engine using a lubricating oil composition comprising: a) at least 50% by mass, based on the mass of the composition, of an oil of lubricating viscosity; (b) 5 to 25% by mass, based on the mass of the composition, of an oil-soluble or oil-dispersible alkali metal or alkaline earth metal salicylate detergent, or a mixture of two or more oil-soluble or oil-dispersible alkali metal or alkaline earth metal salicylate detergents; (c) 0.1 to 10% by mass, based on the mass of the composition of one or more oil-soluble or oil-dispersible ashless dispersants; and optionally, (d) 0.1 to 10% by mass, based on the mass of the composition of a polyalkylene-substituted succinic anhydride.