Granted Patent
Utility
US 5,019,132 · App. 07/442,101
Process for the preparation of concentrated 1:2 metal complex dye preparations
Inventors:
Herb Davis, Charles R. Wetzel
Patented Case
View Patent ↗
Granted: May 28, 1991
Filed: Nov 28, 1989
Inventors
Herb Davis
Charles R. Wetzel
Assignee (at issue)
Ciba-Geigy
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.