Granted Patent
Utility
US 4,231,879 · App. 05/951,314
Apparatus for selective separation of matter through semi-permeable membranes
Inventor:
Kurt Spranger
Patented Case
View Patent ↗
Granted: Nov 4, 1980
Filed: Oct 13, 1978
Inventor
Kurt Spranger
Assignee (at issue)
Gambro Dialysatoren GmbH
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.