Granted Patent
Utility
US 4,343,620 · App. 06/219,202
Propylene oxide polyadducts containing carboxyl groups and their salts
Inventors:
Heinz Abel, Paul Schafer
Patented Case
View Patent ↗
Granted: Aug 10, 1982
Filed: Dec 22, 1980
Inventors
Heinz Abel
Paul Schafer
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.