Lubricant compositions, core-shell nanoparticles, and related methods are disclosed. In an exemplary embodiment, a lubricant composition includes a plurality of core-shell nanoparticles. The nanoparticles include a core, a first shell disposed on the core, and a second shell disposed on the first shell. The first shell is formed from a siliceous material and the second shell is formed from a hydrophobic material. The first and second shells form functional coatings that reduce wear and friction of parts lubricated with the lubricant composition.

This disclosure provides a method for improving high temperature antifoaming performance of a lubricating oil in an engine or other mechanical component lubricated with the lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition with a lubricating oil base stock as a major component, and at least one silicone antifoaming agent, as a minor component. The silicone antifoaming agent is delivered to the lubricating oil by contacting the lubricating oil with a cured silicone (e.g., room temperature vulcanized (RTV) silicone) at a temperature, and for a period of time, sufficient to deliver silicone to the lubricating oil. The delivered silicone is soluble in the lubricating oil. The lubricating oils are useful as passenger vehicle engine oils (PVEO) and commercial vehicle engine oils (CVEO).

A lubricating oil composition comprising a GTL (Gas to-Liquid) base oil synthesized by the Fischer-Tropsch process and a viscosity index improver, wherein the content of the viscosity index improver is 0.1 to 20 mass %, and at least HTHSV 50 C./HTHSV 150 C. is 6.50 or less and KV 50 C./HTHSV 150 C. is 8.00 or less.

A lubricating oil composition comprising a GTL (Gas to-Liquid) base oil synthesized by the Fischer-Tropsch process and a viscosity index improver, wherein the content of the viscosity index improver is 0.1 to 20 mass %, and at least HTHSV 50 C./HTHSV 150 C. is 6.50 or less and KV 50 C./HTHSV 150 C. is 8.00 or less.

A lubricant composition contains a lubricant base oil, (A) a detergent containing magnesium, (B) a compound containing boron, and (C) a zinc dialkyl dithiophosphate. The amount of component (A) is in the range of 200 to 1200 mass ppm [Mg] based on the mass of the lubricant composition, and the amount of component (C) is in the range of 300 to 1000 mass ppm [P] based on the mass of the lubricant composition. Component (C) includes a zinc dialkyl dithiophosphate having a primary alkyl group or a secondary alkyl group; the lubricant composition includes zinc dialkyl dithiophosphate having a secondary alkyl group; the mass ratio of the zinc dialkyl dithiophosphate having a primary alkyl group and the zinc dialkyl dithiophosphate having a secondary alkyl group is from 70:30 to 0:100; and the concentration of [B] is from 100 to 300 mass ppm based on the mass of the lubricant composition.

A lubricant composition comprising a) a synthetic poly-alpha-olefin base fluid; b) an organomolybdenum friction modifier; c) an alkylphosphorothiolate and a hydrocarbylamine anti-wear combination; and d) a dihydrocarbyl dithiophosphate extreme pressure additive and optionally one or more of e) a copper corrosion inhibitor; f) an anti-foam agent; g) a solubilizing agent; h) polymeric viscosity index improver; and i) an oligomeric viscosity modifier is highly suitable for use in the synchronizer of a transmission.

A lubricant composition for application onto a surface of drive elements includes: a base oil; and a silasesquioxane. In an embodiment, the silasesquioxane has the chemical formula [RSiO3/2].sub.n with: n=6, 8, 10, 12; where R independently of one another=alkyl (C1-C20), cycloalkyl (C3-C20), alkenyl (C2-C20), cycloalkenyl (C5-C20), alkynyl (C2-C20), cycloalkynyl (C5-C20), aryl (C6-C18) or heteroaryl group, oxy, hydroxy, alkoxy (C4-C10), oxirane polymer (degree of polymerization with 4 to 20 repeat units), carboxy, silyl, alkylsilyl, alkoxysilyl, siloxy, alkylsiloxy, alkoxysiloxy, silylalkyl, alkoxysilylalkyl, alkylsilylalkyl, halogen, epoxy (C2-C20), ester, aryl ether, fluoroalkyl, blocked isocyanate, acrylate, methacrylate, mercapto, nitrile, amine, and/or phosphine group, each substituted or unsubstituted.

[Problem] To provide an aqueous coating agent composition (in particular, an aqueous coating composition for lubricating films that contains a solid lubricant) which as a whole is excellent in terms of flowability, applicability, and storage stability and which is capable of forming satisfactory and smooth coating films effective in stick-slip inhibition. [Solution] The problem can be solved with an aqueous coating agent composition which comprises (A) a curable resin in an aqueous emulsion form, (B) a surfactant, (C) solid particles, (D) one or more nitrogenous heterocyclic compounds, (E) a film-forming silicone in an aqueous emulsion form, and (F) water. In particular, it is preferable that the (C) component comprise a solid lubricant. In view of the environmental regulations, it is especially preferable that the (D) component be 1,3-dimethyl-2-imidazolidinone.

A composition contains a polyalkylene glycol and a fatty amine ethoxylate, the fatty amine ethoxylate having non-cyclic structure of structure (I). Where R is a linear, non-cyclic carbon-containing group with that is free of nitrogen, x and y are selected from a group consisting of zero and positive values provided that the sum of x and y are in a range of 8-20. ##STR00001##

A method for improving filterability, while maintaining or improving antifoaming performance, of a lubricating oil in an engine or other mechanical component lubricated with the lubricating oil by using as the lubricating oil a formulated oil. A method for improving antifoaming performance, while maintaining or improving filterability, of a lubricating oil in an engine or other mechanical component lubricated with the lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and at least one antifoam agent, as a minor component. A lubricating oil having a composition including a lubricating oil base stock as a major component, and at least one antifoam agent, as a minor component. The antifoam agent is a silicone composition having a highly branched functionalized silicone backbone. The lubricating oils are useful as automotive gear lubricating compositions.