Granted Patent
Utility
US 5,229,465 · App. 07/722,890
Oxygen-permeable polymeric membranes
Inventors:
Eishun Tsuchida, Hiroyuki Nishide, Hiroyoshi Kawakami
Patented Case
View Patent ↗
Granted: Jul 20, 1993
Filed: Jun 28, 1991
Inventors
Eishun Tsuchida
Hiroyuki Nishide
Hiroyoshi Kawakami
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.