Granted Patent
Utility
US 5,411,580 · App. 07/740,902
Oxygen-separating porous membranes
Inventors:
Eishun Tsuchida, Hiroyuki Nishide, Hiroyoshi Kawakami, Yukiko Sasame
Patented Case
View Patent ↗
Granted: May 2, 1995
Filed: Jul 31, 1991
Inventors
Eishun Tsuchida
Hiroyuki Nishide
Hiroyoshi Kawakami
Yukiko Sasame
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.