Patent · US Expired

Lubricating oil composition for internal combustion engines

US5688748A · kind A · utility

25Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 26, 1996
Grant dateNov 18, 1997
Priority date
Expiry dateJan 26, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10N2040/28
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Providing a lubricating oil composition for internal combustion engines which has high resistance to oxidation by nitrogen oxides, excellent friction characteristics that is maintained for a prolonged period, and reduces the fuel consumption for a prolonged period. A lubricating oil composition for internal combustion engines is provided consisting of a base oil principally consisting of a hydrocarbon oil which has a dynamic viscosity of 2-20 mm.sup.2 /s at 100.degree. C. and contains 3 wt % or less aromatic components in total, 45 wt% or more one- and two-ring naphthenes in total, 50 wt ppm or less sulfur and 50 wt ppm or less nitrogen, to which are added, with respect to the total weight of the composition, 0.02-0.2 wt % as molybdenum of molybdenum dithiocarbamate, 0.02-0.15 wt % as phosphorus of zinc dithiophosphate, and 0.05-3 wt % of phenol-based antioxidant. The lubricating oil composition according to the invention has a low friction coefficient, which is maintained for a prolonged period even after oxidation by nitrogen oxides.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.