Granted Patent
Utility
US 4,900,449 · App. 07/052,699
Filtration membranes and method of making the same
Inventors:
Menaham Kraus, Mark Heisler, Inessa Katsnelson, Diosie Velazques
Patented Case
View Patent ↗
Granted: Feb 13, 1990
Filed: May 20, 1987
Inventors
Menaham Kraus
Mark Heisler
Inessa Katsnelson
Diosie Velazques
Assignee (at issue)
Gelman Sciences
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.