Granted Patent
Utility
US 5,329,006 · App. 07/755,717
Chromogenic lactam compounds, their preparation and their use
Inventors:
Hans-Peter Baumann, Ian J. Fletcher
Patented Case
View Patent ↗
Granted: Jul 12, 1994
Filed: Sep 6, 1991
Inventors
Hans-Peter Baumann
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.