| 摘要 |
A lubricating oil composition which can reduce the occurrence frequency of LSPI and which can ensure detergency. The lubricating oil composition which includes a lubricant base oil, a compound having calcium and/or magnesium, a compound having molybdenum and/or phosphorus, and an ashless dispersant having nitrogen and which satisfies X≦−0.85 and Y≧0.18 (wherein X is calculated according to formula (1): X=([Ca]+0.5[Mg])×8−[Mo]×8−[P]×30 and Y is calculated according to formula (2): Y=[Ca]+1.65[Mg]+[N]). The lubricating oil composition for use in an internal combustion engine, more particularly, a lubricating oil composition for use in a supercharged gasoline engine. |
| 主权项 |
1. A lubricating oil composition, comprising: a lubricating oil base oil, a compound having at least one element selected from calcium and magnesium, a compound having at least one element selected from molybdenum and phosphorous, and an ashless dispersant having nitrogen; wherein,
X as determined from following equation (1):
X=([Ca]+0.5[Mg])×8−[Mo]×8−[P]×30 (1) wherein [Ca], [Mg], [Mo] and [P] in equation (1) respectively represent the concentrations (wt %) of calcium, magnesium, molybdenum and phosphorous in the lubricating oil composition, satisfies the expression X≦−0.85; and, Y as determined from following equation (2):
Y=[Ca]+1.65[Mg]+[N] (2) wherein [Ca], [Mg] and [N] in equation (2) respectively represent the concentrations (wt %) of calcium, magnesium and nitrogen derived from ashless dispersant in the lubricating oil composition, satisfies the expression Y≧0.18. |
