Granted Patent
Utility
US 5,348,662 · App. 08/061,790
Process for removing heavy metals from aqueous solutions
Inventors:
Jeffrey H. Yen, Richard C. Spung
Patented Case
View Patent ↗
Granted: Sep 20, 1994
Filed: May 13, 1993
Inventors
Jeffrey H. Yen
Richard C. Spung
Assignee (at issue)
Elf Atochem North America, 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.