Granted Patent
Utility
US 4,898,813 · App. 06/848,691
Catalytic test composition intended to produce a range of colors
Inventors:
James P. Albarella, Steven C. Charlton, James W. Reinsch, Mary E. Warchal
Patented Case
View Patent ↗
Granted: Feb 6, 1990
Filed: Apr 4, 1986
Inventors
James P. Albarella
Steven C. Charlton
James W. Reinsch
Mary E. Warchal
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.