Abstract: A lubricating composition containing an organic molybdenum compound having excellent oxidation stability that provides lubricity for long periods of time is provided. The lubricant comprises a molybdenum amine compound obtained by reacting a compound containing a hexavalent molybdenum atom with an amine represented by the following formula (1): wherein each of R1 to R3 represents a hydrogen atom and/or a hydrocarbon group, and at least one of R1 to R3 is a chain hydrocarbon group having 14 or more carbon atoms; or the following formula (2) wherein R4 represents a chain hydrocarbon group having 10 or more carbon atoms, s represents 0 or 1, X and/or Y represents a hydrogen atom, a hydrocarbon group, an alkanol group or an alkyl amino group having 2 to 4 carbon atoms, and X and Y are not hydrogen atoms or hydrocarbon groups at the same time when s is 0. A lubricating composition containing the lubricant is also provided.

Abstract: In diesel engines, soot is produced by combustion and enters into the engine oil, preventing the engine lubricant from fully exercising its lubricity. The present invention provides a lubricating composition comprising a lubricating basestock, an organic molybdenum compound (A) and succinimide (B) having 0.01 or less of an IR spectrum absorbance peak intensity ratio &agr;/&bgr;, wherein &agr; represents an absorbance peak intensity at 1,550±10 cm−1 and &bgr; represents an absorbance peak intensity at 1,700±10 cm−1. Preferably, the organic molybdenum compound is the compound represented by the following formula (1) or formula (2): (wherein R1 to R8 each independently represent a hydrocarbon, and X1 to X8 each independently represent a sulfur atom or an oxygen atom), or a reaction product of an amine and a molybdenum compound having at least one pentavalent or hexavalent molybdenum atom.

Abstract: There is provided a lubricating composition including a lubricating base containing an asymmetric sulfurized oxymolybdenum dithiocarbamate of the formula (1); a symmetric sulfurized oxymolybdenum dithiocarbamate of the formula (2); and a phenolic or aminic antioxidant. (wherein R1 to R5 are each a hydrocarbon group, provided that R1 to R4 are not concurrently the same group; and X1 to X8 are each a sulfur atom or an oxygen atom.) This lubricating composition meets both the required solubility of additives in base oils and long drain properties concurrently.