Granted Patent
Utility
US 5,068,095 · App. 07/507,386
Method for reducing the amount of colorants in a caustic liquor
Inventors:
William A. Nigro, Gary A. O'Neill
Patented Case
View Patent ↗
Granted: Nov 26, 1991
Filed: Apr 10, 1990
Inventors
William A. Nigro
Gary A. O'Neill
Assignee (at issue)
Aluminum Company of America
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.