Granted Patent
Utility
US 5,981,689 · App. 08/974,119
Poly(vinylamine)-based superabsorbent gels and method of manufacturing the same
Inventors:
Michael A. Mitchell, Thomas W. Beihoffer, Leticia L. Trzupek, Jerald W. Darlington, Jr.
Patented Case
View Patent ↗
Granted: Nov 9, 1999
Filed: Nov 19, 1997
Inventors
Michael A. Mitchell
Thomas W. Beihoffer
Leticia L. Trzupek
Jerald W. Darlington, Jr.
Assignee (at issue)
AMCOL INTERNATIONAL CORPORATION
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.