Lubricating compositions containing a phosphorus-containing salt of an acylated ethylene-α-olefin polymer substituted with an aliphatic polyamine having at least one primary or secondary amine, the lubricating composition having a total phosphorus content in an amount of 200 ppm to 600 ppm by weight of the lubricating composition. The phosphorus-containing salt additive described herein can be used as an anti-wear agent in lubricating composition for diesel engines.

Lubricating compositions containing a phosphorus-containing salt of an acylated ethylene-α-olefin polymer substituted with an aliphatic polyamine having at least one primary or secondary amine, the lubricating composition having a total phosphorus content in an amount of 200 ppm to 600 ppm by weight of the lubricating composition. The phosphorus-containing salt additive described herein can be used as an anti-wear agent in lubricating composition for diesel engines.

Disclosed is a method of lubricating a gas engine using a lubricant including at least one mineral base oil and at least one ester selected from among the polyol esters. The composition includes at least 50% by weight of mineral base oil and at least 5% by weight of polyol ester relative to the total weight of the lubricant composition.

An object of the present invention is to provide a grease composition which has little influence on the environment and has good rust prevention and water resistance against salt water such as sea water. The grease composition comprises a biodegradable base oil and a rust-preventive agent comprising a calcium sulfonate complex and a sorbitan fatty acid ester, wherein a total content of biodegradable organic substances in the grease composition is 75% by mass or more, and wherein a content of the rust-preventive agent is 2.5 to 30% by mass.

The invention relates to a lubricant composition comprising: at least one base oil for coming into contact with food, selected from the groups II, III or V according to the categories defined in the API classification or the equivalents thereof according to the ATIEL classification; at least one hydrogenated polyisobutylene; and at least one ester polymer.

The invention relates to a lubricant composition comprising: at least one base oil for coming into contact with food, selected from the groups II, III or V according to the categories defined in the API classification or the equivalents thereof according to the ATIEL classification; at least one hydrogenated polyisobutylene; and at least one ester polymer.

The present invention aims to provide a viscosity index improver composition and a lubricating oil composition having a low HTHS viscosity at 100° C., an excellent shear stability, and an excellent low temperature viscosity. The present invention relates to, for example, a viscosity index improver composition (C), containing: a copolymer (A) containing a polyolefin-based monomer (a) represented by the following formula (1) as a constituent monomer; a copolymer (B) containing a (meth)acrylic acid alkyl ester (c) having a C12-C15 straight-chain or branched alkyl group and a (meth)acrylic acid alkyl ester (d) having a C16-C20 straight-chain or branched alkyl group as constituent monomers; and a base oil, wherein a weight average molecular weight ratio {(A)/(B)} of the copolymer (A) to the copolymer (B) is 2 to 55, and a weight ratio (A/B) of the copolymer (A) to the copolymer (B) constituting the viscosity index improver composition (C) is 5 to 100:

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Provided is a grease composition which contains (A) a mixed base oil containing (A1) a low-viscosity base oil having a kinematic viscosity at 40° C. of 10 to 50 mm.sup.2/s and (A2) a high-viscosity base oil having a kinematic viscosity at 40° C. of 200 to 700 mm.sup.2/s, (B) a lithium-based thickener and (C) a polymer having a kinematic viscosity at 100° C. of 1,000 to 100,000 mm.sup.2/s, and has an apparent viscosity at −10° C., as measured according to JIS K2220:2013 and at a shear rate of 10 s.sup.−1, of 50 to 250 mPa.Math.s. The grease composition is excellent in pumpability and is also excellent in wear resistance under poor lubrication conditions.

A grease composition which contains a base oil (A), a urea-based thickener (B), a sarcosine derivative (C), and a fatty acid zinc salt (D), wherein particles containing the urea-based thickener (B) in the grease composition satisfies Requirement (I). The base oil (A) is a blended base oil containing a high viscosity hydrocarbon-based synthetic oil having a specific kinematic viscosity (A1). A low viscosity hydrocarbon-based synthetic oil having a specific kinematic viscosity (A2). An ultra-high viscosity hydrocarbon-based synthetic oil has a number average molecular weight (Mn) of 2,500 to 4,500 and a specific kinematic viscosity (A3). A 40° C. kinematic viscosity of the base oil (A) is 500 mm.sup.2/s to 1,500 mm.sup.2/s. A viscosity index of the base oil (A) is 140 or more. A content of the fatty acid zinc salt (D) is 10 mass % to 20 mass % based on a total amount of the grease composition.

The present invention relates to the use of lubricant composition containing a base oil and at least one alkyl methacrylate polymer, to reduce engine particulate emissions.