| 摘要 |
PURPOSE: To obtain a lubricating oil composition which can retain a friction- reducing effect on an engine over long without suffering influences of NOX gases by incorporating a specific metal compound, a sulfur compound, a metallized detergent, and a boron compound. CONSTITUTION: A lube base oil is compounded with (A) a molybdenum oxysulfide dithiocarbamate having at least one 8-18C alkyl, (B) zinc dialkyl dithiophosphate having at least one 1-18C primary alkyl, (C) a sulfur compound such as a zinc dialkyldithiocarbamate having at least one 2-18C alkyl, an olefin sulfide, etc., (D) a metallized detergent such as calcium salicylate, and (E) a boron compound, the amounts of the ingredients (A) to (E) being 200-2,000ppm in terms of molybdenum, 0.02-0.15wt.% in terms of phosphorus, 0.02-0.30wt.% in terms of sulfur, 1-10wt.%, and 0.005-0.06wt.% in terms of boron, respectively. |
