Granted Patent
Utility
US 4,247,293 · App. 06/011,452
Sulphonated, aromatic reaction products, processes for their manufacture and their use as substances having a tanning action
Inventor:
Albert Wurmli
Patented Case
View Patent ↗
Granted: Jan 27, 1981
Filed: Feb 12, 1979
Inventor
Albert Wurmli
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.