The present invention relates to a grease composition containing a base oil (A), a thickener (B), and an additive (C) composed of at least two selected from a sarcosine derivative (C1), an amine compound (C2), and an amide compound (C3), wherein the content of the component (C) is 0.1 to 10.0% by mass on a basis of the total amount of the grease composition.

A lubricant composition comprising an oil of lubricating viscosity and an N-hydrocarbyl-substituted γ-aminoester or γ-aminothioester, wherein the N-hydrocarbyl substituent comprises a hydrocarbyl group of at least 3 carbons atoms, with a branch at the 1 or 2 position of the hydrocarbyl chain, provides exhibits basicity and good seal performance.

The invention provides a lubricating composition containing (a) an oil of lubricating viscosity, (b) a phosphite having at least one hydrocarbyl group that has 4 or more carbon atoms, and (c) a compound derived from a hydroxy-carboxylic acid. The invention further relates to the use of the lubricating composition in an internal combustion engine.

A lubricating composition includes an oil of lubricating viscosity and a low-ash additive system including a low molecular weight amine with a Total Base Number of at least 150, and an N-substituted hydrocarbyl-substituted succinimide dispersant. The low-ash additive system provides the lubricating composition with a significant boost in TBN without substantially lowering the flashpoint. The composition is particularly suited to use as a marine diesel engine lubricant.

Disclosed is a magnetic dendrimer compound and a method for preparing the magnetic dendrimer compound, the molecular formula of which is shown in formula (I): Γ(CH.sub.2).sub.3N.sub.(2.sup.n+1.sub.−1)R.sup.1.sub.(2.sup.n+2.sub.−2)R.sup.2.sub.(2.sup.n+1.sub.)(I). In this formula, Γ indicates magnetic particles coated with SiO.sub.2 on a surface thereof, the magnetic particles having been modified by a silane coupling agent; (CH.sub.2).sub.3N.sub.(2.sup.n+1.sub.−1)R.sup.1.sub.(2.sup.n+2.sub.−2) is a dendritic group, and R.sup.2.sub.(2.sup.n+1.sub.) is a lipophilic group, with 0≤n≤100. Further disclosed is a lubricant comprising the magnetic dendrimer compound.

A quaternary ammonium compound of formula (I): ##STR00001##
wherein R.sup.0, R.sup.1, R.sup.2 and R.sup.3 is each independently an optionally substituted hydrocarbyl group, X is a linking group, R.sup.4 is an optionally substituted alkylene group, R.sup.5 is hydrogen or an optionally substituted alkyl, alkenyl or aryl group, and n is 0 or a positive integer, provided that n is not 0 when R.sup.5 is hydrogen.

A lubricant composition comprising: (i) silver or gold nanoparticles, each of which is encapsulated by a layer of alkylthiol or alkylamine molecules; (ii) palladium or platinum nanoparticles, each of which is encapsulated by a layer of alkylthiol or alkylamine molecules; and (iii) a fluid in which components (i) and (ii) are present. Further described are methods for applying the lubricant composition onto a mechanical device for which lubrication is beneficial, with resulting improvement in friction and wear reduction and/or corrosion inhibition.

The present invention is a lubricating agent containing a compound represented by the following formula 1:

##STR00001##

wherein R.sup.1 and R.sup.2 each represent a hydrocarbon group with 6 or more and 24 or less carbons; A.sup.10 and A.sup.2O each represent an alkyleneoxy group with 2 or more and 4 or less carbons; x1 and x2 are average numbers of added moles, and each represent a number of 0 or more and 10 or less; and M is a cationic ion.

A quaternary ammonium compound of formula (I): wherein R.sup.0, R.sup.1, R.sup.2 and R.sup.3 is each independently an optionally substituted hydrocarbyl group, X is a linking group, R.sup.4 is an optionally substituted alkylene group, R.sup.5 is hydrogen or an optionally substituted alkyl, alkenyl or aryl group, and n is 0 or a positive integer, provided that n is not 0 when R.sup.5 is hydrogen. ##STR00001##

The present invention provides a water-soluble metalworking oil composition, including: 5.0 to 20.0 mass % of a sulfur compound (A) that is one or more kinds selected from the group consisting of a sulfurized fat and oil and a sulfurized ester and has a kinematic viscosity of 10 to 800 mm.sup.2/s at 40° C.; 0.5 to 20.0 mass % of the nonionic surfactant (B) having an HLB of 6 to 18; 7.0 to 30.0 mass % of an unsaturated fatty acid polymer (C); and an amine compound (D) selected from the group consisting of a tertiary amine and a secondary amine.