| 摘要 |
PROBLEM TO BE SOLVED: To provide a lubricating oil composition sufficiently conforming with severe operation conditions of a 2-cycle cross-head diesel engine for a large-sized boat. SOLUTION: This lubricating oil for a diesel internal combustion engine is obtained by dissolving or dispersing the following components in a base oil and having≥30 and <60 TBN. The components are; an overbased sulfurized alkylphenol calcium salt detergent, an overbased calcium alkylbenzene sulfonate detergent, a nitrogen atom-containing ash-less dispersant and zinc dihydrocarbyldithiophosphate [provided that the mass ratio of the calcium derived from the overbased sulfurized alkylphenol calcium salt detergent to the calcium derived from the overbased calcium alkylbenzenesulfonate detergent is in the (10:90) to (40:60) range]. COPYRIGHT: (C)2007,JPO&INPIT |
