Patent · US Expired

Lubricating oil composition for internal combustion engine

US7648947B2 · kind B2 · utility

0Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 27, 2003
Grant dateJan 19, 2010
Priority date
Expiry dateJul 9, 2024

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10N2040/25
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The present invention provides a lubricating oil composition for an internal combustion engine which is very good in base number retention property, detergency at high temperature and valve train anti-wear property and does not substantially contain phosphorus- and/or sulfur-containing anti-wear agent. The composition comprises a lubricant base oil comprising a mineral oil and/or a synthetic oil, (A) 0.001 to 0.5% by mass of an ester of a boric acid in terms of boron element therein and (B) 0.01 to 5% by mass of an ashless antioxidant, wherein said composition contains substantially no metal salts of dithiophosphoric acid and has a sulfur content of 0.2% by mass or less, each percentage being based on a total mass of the composition.

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