| 摘要 |
PROBLEM TO BE SOLVED: To provide a lubricating oil composition having a narrow fluctuation width of kinetic viscosity and a viscosity index even under a high temperature oxidative condition, and thus being usable in the same state at any time while maintaining friction characteristics. SOLUTION: The lubricating oil composition is prepared by blending a base oil of a synthetic oil and/or a mineral oil with a polymethacrylate having a phosphate ester added to its terminal and a phenolic antioxidant. The lubricating oil composition may be further blended with at least one ingredient selected from the group consisting of alkaline earth metal salts of a sulfonate, a phenate, and a salicylate. The lubricating oil is also prepared by blending a base oil of a synthetic oil and/or a mineral oil with a polymethacrylate having a phosphate ester added to its terminal, an amine-based antioxidant, and an alkaline earth metal salt of a salicylate. COPYRIGHT: (C)2008,JPO&INPIT |
