Granted Patent
Utility
US 4,749,489 · App. 06/868,478
Polyphosphazene semipermeable membranes
Inventors:
Charles A. Allen, Robert R. McCaffrey, Daniel Cummings, Alan E. Grey, Janine S. Jessup, Richard E. McAtee
Patented Case
View Patent ↗
Granted: Jun 7, 1988
Filed: May 30, 1986
Inventors
Charles A. Allen
Robert R. McCaffrey
Daniel Cummings
Alan E. Grey
Janine S. Jessup
Richard E. McAtee
Assignee (at issue)
United States Department of Energy
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.