Granted Patent
Utility
US 6,420,439 · App. 09/292,642
Crosslinked, non-swellable ampholytic base resins
Inventors:
Martin Grendze, Donald W. McQuigg, John T. Wyeth, Ernest Crowe, Katherine M. Weisheit, Eric F. V. Scriven
Patented Case
View Patent ↗
Granted: Jul 16, 2002
Filed: Apr 15, 1999
Inventors
Martin Grendze
Donald W. McQuigg
John T. Wyeth
Ernest Crowe
Katherine M. Weisheit
Eric F. V. Scriven
Assignee (at issue)
Reilly Industries, Inc.
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.