Granted Patent
Utility
US 5,298,169 · App. 07/933,227
Treatment of waste sulfuric acid by gypsum precipitation in a titanium dioxide process
Inventors:
Roger Laferriere, Pierre Beaupre
Patented Case
View Patent ↗
Granted: Mar 29, 1994
Filed: Aug 21, 1992
Inventors
Roger Laferriere
Pierre Beaupre
Assignee (at issue)
Kronos, Inc.
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.