Granted Patent
Utility
US 5,492,995 · App. 08/383,833
Polycondensates containing phosphinic or phosphonic acid groups and siloxane groups
Inventors:
Fritz Engelhardt, Karl-Heinz Keil, Jurgen Kuhlwein, Wilfried Schuler, Willi Steckelberg, Ralf Zerrer, Werner Antwerpen
Patented Case
View Patent ↗
Granted: Feb 20, 1996
Filed: Feb 6, 1995
Inventors
Fritz Engelhardt
Karl-Heinz Keil
Jurgen Kuhlwein
Wilfried Schuler
Willi Steckelberg
Ralf Zerrer
Werner Antwerpen
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.