A lubricating oil composition including a base oil, a phosphorous acid ester, an imide-based compound, an amide-based compound, an amine-based compound, and a benzotriazole-based compound, wherein a content of the benzotriazole-based compound is 0.005 to 1.00 mass % based on the total amount of the lubricating oil composition.

A tribological system, including a main body and a sandwich lubrication, wherein the sandwich lubrication includes a binder-free solid lubricant layer including a solid lubricant, and a lubricant layer including a lubricant. The binder-free solid lubricant layer and the lubricant layer are present as separate layers on the main body and the mass ratio of solid lubricant to lubricant is at most 0.05:1. The solid lubricant includes polytetrafluoroethylene (PTFE), metal sulfide, graphite, graphene, boron nitride (hexagonal), calcium phosphate, silicate, layered silicate, or mixtures thereof.

The disclosed technology relates to a lubricant composition for automotive gears, axles and bearings, the lubricant composition containing an oil of lubricating viscosity and a metal thiophosphate compound, such as zinc dialkyldithiophosphate, as well as a method of obtaining extreme pressure performance in automotive gears, axles and bearings at lower sulfur content than is typical, by lubricating such automotive gears, axles and bearings with a lubricant composition containing a metal thiophosphate compound, such as zinc dialkyldithiophosphate.

A lubricating oil additive composition including: (i) a Broensted acid salt of at least one first amide compound, the Broensted acid salt being a salt of the first amide compound and a Broensted acid, the first amide compound being a monoamide of at least one fatty acid (a1), and at least one amine compound (a2), the amine compound (a2) being an oligomer of at least one alkanolamine (a3) represented by the general formula (1):

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in the formula, n is 1 or 2; R.sup.1 is C1-4 linear chain alkylene or C3-10 branched chain alkylene, the C3-10 branched chain alkylene having a main chain, the main chain having a carbon number of 2; and when n is 2, a plurality of R.sup.1's may be the same, and may be different from each other.

A composition comprising water and a polyalkylene glycol having an allyl content of less than 20 eq/g, which composition has reduced foaming properties and preferably a biodegradability of at least 60% as determined using OECD 301F. The polyalkylene glycol can be made by forming a first intermediate comprising an oxypropylene block by reacting propylene oxide with a polyol initiator in the presence of a Double Metal Cyanide catalyst, and then reacting the first intermediate with ethylene oxide in the presence of a KOH catalyst.

The disclosed technology relates to lubricants for driveline and industrial gears containing a combination of viscosity modifiers along with optional esters, as well as a method of lubricating driveline and industrial gears with such a lubricant.

Disclosed are solvency enhancer compositions, for example, as additives to lubricating oils and as formulated in lubricating oil compositions and associated methods of preparation and use thereof. The compositions and methods can dissolve at least one of oxidation products and other organic polar compounds, due to lubricant degradation, formed and suspended in oil compositions including adding an effective amount of a solvency enhancer to the oils, wherein the solvency enhancer includes Guerbet alcohols. Further described are methods for dissolving organic deposits in an oil system including adding an effective amount of a solvency enhancer to the oil system, wherein the solvency enhancer includes Guerbet alcohols. Also provided are methods for preventing sludge and varnish formation in in-service oils including adding an effective amount of a solvency enhancer to the oils, wherein the solvency enhancer includes Guerbet alcohols.

The disclosed technology relates to a lubricant composition for automotive or industrial gears, as well as axles and bearings, the automotive or industrial gear oil containing an oil of lubricating viscosity, an optional phosphate and/or thiophosphate compound, a particular sulfurized olefin, either a metal thiophosphate compound, such as zinc dialkyldithiophosphate, a thiadiazole functionalized dispersant, or a mixture thereof, and a hydroxyl/amine containing booster, as well as a method of improving automotive or industrial gear operating efficiency and temperature by lubricating such automotive or industrial gears with the automotive or industrial gear oil.

A lubricating oil composition contains a base oil (A), a zinc dithiophosphate (B), and a sarcosine compound (C), the composition having a content of the sarcosine compound (C) of more than 0.05% by mass and 0.40% by mass or less based on the entire amount of the lubricating oil composition, and satisfying requirement () or (): Requirement (): when the content of the sarcosine compound (C) is more than 0.05% by mass and less than 0.20% by mass based on the lubricating oil composition, one or more phosphorus compounds (D) selected from an acidic phosphoric acid ester (D1) and an amine salt thereof (D2) are optionally contained; Requirement (): when the content of the sarcosine compound (C) is 0.20% to 0.40% by mass based on the lubricating oil composition, the phosphorus compound (D) is contained in an amount less than 0.50% by mass based on the lubricating oil composition.