Granted Patent
Utility
US 4,277,247 · App. 06/108,270
Process for dyeing pre-cleaned cellulose fiber material
Inventors:
Karlheinz Keller, Lotti Furer
Patented Case
View Patent ↗
Granted: Jul 7, 1981
Filed: Dec 31, 1979
Inventors
Karlheinz Keller
Lotti Furer
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.