LUBRICATING OIL COMPOSITION HAVING IMPROVED CORROSION RESISTANCE AND SEALING MATERIAL PROTECTING CHARACTERISTIC

摘要

PROBLEM TO BE SOLVED: To provide a fully formulated lubricating oil having improved lubricating characteristics, to provide a lubricated surface and to provide an additive concentrate for the lubricating oil. SOLUTION: A lubricating oil composition comprises a dispersant mixture produced from a reaction product of a polyalkylene compound with a carboxylic acid-based acylating agent and a polyamine. The polyalkylene compound of at least one dispersant in the dispersant mixture has at least about 1,200 number-average molecular weight and at least the one dispersant in the dispersant mixture contains boron. The weight ratio (B/N) of boron to nitrogen in the dispersant mixture is about 0.25 to about 1.0. COPYRIGHT: (C)2008,JPO&INPIT