Granted Patent
Utility
US 4,891,067 · App. 07/193,873
Processes for the treatment of smelter flue dust
Inventors:
Alkis S. Rappas, Brett T. Waterman
Patented Case
View Patent ↗
Granted: Jan 2, 1990
Filed: May 13, 1988
Inventors
Alkis S. Rappas
Brett T. Waterman
Assignee (at issue)
Kennecott Utah Copper LLC
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.