Granted Patent
Utility
US 5,256,253 · App. 07/934,841
Methods for inhibiting barium sulfate deposition using a poly(amine)compound or its salts in papermaking systems
Inventors:
Davor F. Zidovec, Alexander D. Fisher, David D. Dreisbach
Patented Case
View Patent ↗
Granted: Oct 26, 1993
Filed: Aug 24, 1992
Inventors
Davor F. Zidovec
Alexander D. Fisher
David D. Dreisbach
Assignee (at issue)
Betz PaperChem Inc.
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.