Granted Patent
Utility
US 4,480,096 · App. 06/227,294
Chromogenic quinazolines
Inventor:
Ian J. Fletcher
Patented Case
View Patent ↗
Granted: Oct 30, 1984
Filed: Jan 22, 1981
Inventor
Ian J. Fletcher
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.