The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 19, 1993
Filed:
Nov. 02, 1992
Applicant:
Inventors:
David K Walters, Camberley, GB;
Arthur S Thomas, Swansea, GB;
Assignee:
Ethyl Petroleum Additives Limited, Bracknell, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C10M / ; C10M / ;
U.S. Cl.
CPC ...
252 / ; 252 / ; 252 34 ; 252 / ; 252 / ;
Abstract
Lubricant compositions especially useful as hydraulic fluids contain a metal-free anti-wear or load-carrying additive containing sulphur and/or phosphorus and an amino succinate ester as corrosion inhibitor. Such compositions are free from heavy metal and have improved environmental acceptability where heavy metals are to be avoided, e.g. in agriculture. The lubricant base stock may be a biodegradable natural oil.