Abstract: A lubricating oil composition includes at least one base oil selected from the group consisting of a mineral oil-based lubricating oil, a synthetic oil-based lubricating oil, and a mixed oil thereof, zinc dialkyldithiophosphate X represented by Formula (1), and an acid phosphate ester amine salt Y represented by Formula (2), in which a content PX of the X is from 0.06% by mass to 0.08% by mass in terms of phosphorus concentration with respect to a total mass of the lubricating oil composition, and a content PY of the Y is from 0.015% by mass to 0.025% by mass in terms of phosphorus concentration with respect to the total mass of the lubricating oil composition.

Abstract: A lubricating oil composition for a sliding guide surface, which includes a lubricant base oil, an acid phosphate ester mixture having a structure represented by the following Formula (1) and including an acid phosphate monoester and an acid phosphate diester, and an aliphatic monoamine, and which satisfies a predetermined condition A or condition B, is provided. In Formula (1), each of R1 and R2 represents a hydrogen atom or a saturated or unsaturated straight-chain aliphatic hydrocarbon group having from 1 to 30 carbon atoms, and R1 and R2 are not simultaneously hydrogen atoms.

Abstract: A lubricating oil composition including: at least one base oil selected from a mineral oil-based lubricating oil, a synthetic oil-based lubricating oil, or a mixed oil thereof, and zinc dialkyldithiophosphates X consisting of the compounds Z1 to Z3 represented by the formulae (1) to (3) are contained, in which a total content of the zinc dialkyldithiophosphates X is 0.02% by mass or more in terms of phosphorus concentration with respect to the total mass of the oil composition, and the zinc dialkyldithiophosphates X satisfy the formulae (a) to (c). In the formula (1), each of R1 to R4 independently represents a linear or branched primary alkyl group having from 10 to 20 carbon atoms. In the formula (2), each of R5 to R8 independently represents a linear or branched primary alkyl group having from 7 to 9 carbon atoms. In the formula (3), each of R9 to R12 independently represents a linear or branched primary or secondary alkyl group having from 3 to 6 carbon atoms.

Abstract: A conductive lubricating oil composition including at least one lubricating base oil selected from the group consisting of compounds represented by the following General Formula (1) and compounds represented by the following General Formula (2), and at least one conductivity imparting agent selected from the group consisting of potassium trifluoromethanesulfonate, lithium trifluoromethanesulfonate, lithium nonafluorobutanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, and lithium tris(trifluoromethanesulfonyl)methide, in an amount of from 0.01% by mass to 1% by mass, and having a rate of change in conductivity after storage at 120° C. for 200 hours of 10% or less. The definitions of R1, R2, m and n in the formulae are as indicated in the specification. Cases of m?n=2 are excluded.

Abstract: An engine oil composition includes a star polymer (A) and a poly(alkyl (meth)acrylate) (B) as a viscosity index improver, and has a viscosity index of 185 to 230, the star polymer (A) having a star structure and having a weight average molecular weight of 100,000 to 1,000,000, the star structure being a structure in which polymer chains branch from a center of the polymer, the polymer chains being obtained by copolymerization and hydrogenation of an aromatic vinyl compound monomer and a conjugated diene monomer, the poly(alkyl (meth)acrylate) (B) having a weight average molecular weight of 200,000 to 600,000, the content (MA) of the star polymer (A) in the engine oil composition being 0.10 to 2.00 mass % based on the total mass of the engine oil composition, the content (MB) of the poly(alkyl (meth)acrylate) (B) in the engine oil composition being 0.50 to 6.00 mass % based on the total mass of the engine oil composition, and the ratio “MA/MB” being 0.10 to 1.00.

Abstract: An engine oil composition includes a star polymer (A) and a poly(alkyl (meth)acrylate) (B) as a viscosity index improver, and has a viscosity index of 185 to 230, the star polymer (A) having a star structure and having a weight average molecular weight of 100,000 to 1,000,000, the star structure being a structure in which polymer chains branch from a center of the polymer, the polymer chains being obtained by copolymerization and hydrogenation of an aromatic vinyl compound monomer and a conjugated diene monomer, the poly(alkyl (meth)acrylate) (B) having a weight average molecular weight of 200,000 to 600,000, the content (MA) of the star polymer (A) in the engine oil composition being 0.10 to 2.00 mass % based on the total mass of the engine oil composition, the content (MB) of the poly(alkyl (meth)acrylate) (B) in the engine oil composition being 0.50 to 6.00 mass % based on the total mass of the engine oil composition, and the ratio “MA/MB” being 0.10 to 1.00.

Abstract: The present invention provides a highly thermal conductive compound which has a high thermal conductivity, has a high consistency and a good coating workableness, and is excellent in thermal stability at a high temperature. A highly thermal conductive compound containing (A) 85 to 97% by mass of an inorganic powder filler, (B) 2 to 15% by mass of a base oil, and (C) 0.001 to 10% by mass of a compound represented by Y—(—R2—COO—)n—R1—X (wherein R1 and R2 each is a bivalent hydrocarbon group having a linear or branched chain having 1 to 36 carbon atoms, n is 1 to 15, X and Y each is at least one substituent selected from the group consisting of a carboxyl group and a hydroxyl group or a hydrogen atom, and at least one of X and Y is a carboxyl group or a hydroxyl group.

Abstract: The present invention provides a highly thermal conductive compound which has a high thermal conductivity, has a high consistency and a good coating workableness, and is excellent in thermal stability at a high temperature. A highly thermal conductive compound containing (A) 85 to 97% by mass of an inorganic powder filler, (B) 2 to 15% by mass of a base oil, and (C) 0.001 to 10% by mass of a compound represented by Y—(—R2—COO—)n—R1—X (wherein R1 and R2 each is a bivalent hydrocarbon group having a linear or branched chain having 1 to 36 carbon atoms, n is 1 to 15, X and Y each is at least one substituent selected from the group consisting of a carboxyl group and a hydroxyl group or a hydrogen atom, and at least one of X and Y is a carboxyl group or a hydroxyl group; in the case where n is 2 to 15, the moiety of (—R2—COO—)n in the formula (1) may be a copolymer group composed of two or more constitutional units (—R2—COO—) wherein R2 is a bivalent hydrocarbon group different from one another).