Granted Patent
Utility
US 4,959,170 · App. 07/274,691
Rinsing composition free from phosphate
Inventors:
Hannsjorg Ulrich, Lothar Westermann
Patented Case
View Patent ↗
Granted: Sep 25, 1990
Filed: Nov 21, 1988
Inventors
Hannsjorg Ulrich
Lothar Westermann
Assignee (at issue)
Hoechst GmbH
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.