Granted Patent
Utility
US 4,203,847 · App. 05/800,575
Making porous membranes and the membrane products
Inventor:
Joseph D. Grandine
Patented Case
View Patent ↗
Granted: May 20, 1980
Filed: May 25, 1977
Inventor
Joseph D. Grandine
Assignee (at issue)
Millipore Corporation
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.