Patent · US Expired

Lubricating oil composition

US5091099A · kind A · utility

11Cited by
12References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 1, 1989
Grant dateFeb 25, 1992
Priority date
Expiry dateJun 1, 2009

Classification

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

Abstract

Phosphite-free lubricating oil composition which comprises a) a mineral oil or a synthetic oil or a mixture thereof, and b) a mixture containing at least one aromatic amine of the formula (I), ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.3 ' are as defined in claim 1, and at least one phenol of the formula ##STR2## in which R.sup.4, R.sup.5 and A are as defined in claim 1, and the compounds are present in the mixture in a ratio of 2 to 6 parts by weight of the aromatic amine(s) of the formula I to 1 part by weight of the phenol(s) of the formula II. The lubricating oil compositions are highly resistant to ageing and are effective in preventing black sludge formation.

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