IP Library › Granted Patent US 5,942,471
Granted Patent Utility
US 5,942,471 · App. 07/907,078

Dispersant and antioxidant VI improvers based on olefin copolymers containing phenothiazine and aromatic amine groups

Inventors: Maria M. Kapuscinski, Robert T. Biggs
Patented Case View Patent ↗
Granted: Aug 24, 1999 Filed: Jul 1, 1992
Inventors
Maria M. Kapuscinski
Robert T. Biggs
Assignee (at issue)
Ethyl Corporation

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Quick Facts
Patent No.
US 5,942,471
App. No.
07/907,078
Filed
1992-07-01
Granted
1999-08-24
Kind
A