Granted Patent
Utility
US 6,497,747 · App. 09/404,724
Production and use of improved polyimide separation membranes
Inventors:
Yong Ding, Benjamin Bikson, Joyce K. Nelson
Patented Case
View Patent ↗
Granted: Dec 24, 2002
Filed: Sep 24, 1999
Inventors
Yong Ding
Benjamin Bikson
Joyce K. Nelson
Assignee (at issue)
Praxair Technology, 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.