A lubricant composition comprises an anti-wear and or/friction modifying additive which is an ester of a fatty acid and a polyol. At least 50% by weight of the additive is in the form of a mono-ester, and is preferably a mono-glyceride. The lubricant composition may be used in an internal combustion engine.

Turbine lubricant additives and lubricants including such additives that provide rust prevention and water separation but also pass the demanding stage II wet filterability at the same time.

Provided is a lubricating oil composition containing a base oil (A) and an amine-based antioxidant (B), wherein the component (B) contains a phenyl-naphthylamine (B1), an alkylphenyl-naphthylamine (B2) and a di(alkylphenyl)amine (B3), the content of the component (B1) is 2.0 to 10.0% by mass relative to 100% by mass of the total amount of the component (B), the content of the component (B2) is 40.0 to 90.0% by mass relative to 100% by mass of the total amount of the component (B), and the content of the component (B3) is 8.0 to 50.0% by mass relative to 100% by mass of the total amount of the component (B). The lubricating oil composition maintains excellent oxidation stability even in long-term use in high-temperature environments, and has an excellent lifetime and is excellent also in a sludge preventing effect.

A lubricating oil composition for industrial gears, including 10 to 90% by mass of a lubricant base oil (A) having a kinematic viscosity at 100° C. of 1 to 100 mm.sup.2/s, a viscosity index of 100 or more, and a pour point of 0° C. or lower, and 90 to 10% by mass of a liquid random copolymer (B) of ethylene and α-olefin, the liquid random copolymer (B) being prepared by means of a specific catalyst, wherein the total amount of (A) and (B) is 100% by mass, the lubricating oil composition for industrial gears having a kinematic viscosity at 40° C. of 100 to 10,000 mm.sup.2/s.

Provided is a lubricating oil composition comprising a base oil (A) containing a polyalkylene glycol (A1) and a polyol ester (A2), a phosphorus-based rust inhibitor (B), and an antioxidant (C) containing an amine-based antioxidant (C1). The lubricating oil composition exhibits a strong effect for suppressing sludge sedimentation even when used for an extended period of time in a high-temperature environment, and has excellent demulsibility and rust preventive properties, and therefore, can be suitably used in turbomachinery, compressors, hydraulic equipment, and machine tools.

Lubricant compositions comprising a base oil, one or more antioxidants selected from a group consisting of N-α-naphthyl-N-phenylamine antioxidants and diphenylamine antioxidants; and a sulfur-containing additive comprising up to seven carbon atoms exhibit outstanding oxidative stability and non-corrosion properties. The N-α-naphthyl-N-phenylamine antioxidants plus diphenylamine antioxidants in total may be present from about 0.2 wt % to about 0.8 wt %, based on the total weight of the lubricant composition. The sulfur provided by the sulfur-containing additive may be present from about 50 ppm to about 1000 ppm by weight, based on the total weight of the lubricant composition.

An organometallic chemistry-based compound for preventing coke formation in a hydrocarbon fluid system. The organometallic chemistry-based compound includes a coordination complex that interrupts an autoxidative pathway of coke formation. A component and a system for mitigating coke formation during delivery or circulation of a hydrocarbon fluid. The component includes a contact surface configured to be in contact with the hydrocarbon fluid. The contact surface is functionalized with an inhibitor ligand to form an inhibitor ligand-functionalized surface. The inhibitor ligand-functionalized surface interrupts an autoxidative pathway of coke formation.

The invention relates to phosphorous-containing compounds useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.

A multi-functional olefin copolymer viscosity index improver and a lubricating oil composition including such lubricant additive that provides improved viscometric properties and helps reduce low speed pre-ignition events at the same time. In one approach, the multi-functional olefin copolymer viscosity index improver is silicone functionalized and includes an acylated olefin copolymer with aminosilane or aminosiloxone pendant or side groups.

The invention relates to a use of a lubricant comprising a polyalkylene glycol for reducing white etching cracks in lubricated metal surfaces; and to a method for reducing white etching cracks in lubricated metal surfaces comprising the steps of lubricating the metal surfaces with a lubricant comprising the polyalkylene glycol.