Granted Patent
Utility
US 4,211,645 · App. 05/790,852
Foam flotation activated sludge process
Inventors:
James E. Zajic, Martha A. Hill, Donald F. Manchester, Karel Muzika
Patented Case
View Patent ↗
Granted: Jul 8, 1980
Filed: Apr 25, 1977
Inventors
James E. Zajic
Martha A. Hill
Donald F. Manchester
Karel Muzika
Assignee (at issue)
Abitibi Paper Company Ltd.
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.