Granted Patent
Utility
US 5,281,491 · App. 07/808,591
Battery separator
Inventors:
Burton M. Rein, Howard J. Troffkin, Robert M. Spotnitz, Richard T. Giovannoni, Yihong Guo
Patented Case
View Patent ↗
Granted: Jan 25, 1994
Filed: Dec 20, 1991
Inventors
Burton M. Rein
Howard J. Troffkin
Robert M. Spotnitz
Richard T. Giovannoni
Yihong Guo
Assignee (at issue)
W. R. Grace & Co.
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.