Granted Patent
Utility
US 6,054,615 · App. 09/321,317
Fluorinated quaternary ammonium salts
Inventor:
Weiming Qiu
Patented Case
View Patent ↗
Granted: Apr 25, 2000
Filed: May 27, 1999
Inventor
Weiming Qiu
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND COMPANY
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.