Granted Patent
Utility
US 5,028,237 · App. 07/587,386
Dyeing process using graft polymers which are water soluble or dispersible in water as dyeing assistants
Inventor:
Hans-Ulrich Berendt
Patented Case
View Patent ↗
Granted: Jul 2, 1991
Filed: Sep 25, 1990
Inventor
Hans-Ulrich Berendt
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.