Granted Patent
Utility
US 5,389,711 · App. 07/479,898
Plasticisers for salt functionalized polyvinyl aromatics
Inventors:
Paul A. Westbrook, Leonard E. Gerlowski
Patented Case
View Patent ↗
Granted: Feb 14, 1995
Filed: Feb 14, 1990
Inventors
Paul A. Westbrook
Leonard E. Gerlowski
Assignee (at issue)
SHELL OIL COMPANY
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.