Granted Patent
Utility
US 4,146,558 · App. 05/839,975
Azo dyestuff intermediate nitro- or aminobenzenes ring-substituted by a quaternized amine alkyl or amino-alkoxy group
Inventors:
Patrick J. Jefferies, Nathan N. Crounse
Patented Case
View Patent ↗
Granted: Mar 27, 1979
Filed: Oct 6, 1977
Inventors
Patrick J. Jefferies
Nathan N. Crounse
Assignee (at issue)
Sterling Drug, 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.