Granted Patent
Utility
US 4,837,013 · App. 07/091,149
Quaternized nitrogen containing compounds
Inventors:
Robert B. Login, Ratan K. Chaudhuri, David J. Tracy, Michael W. Helioff
Patented Case
View Patent ↗
Granted: Jun 6, 1989
Filed: Aug 28, 1987
Inventors
Robert B. Login
Ratan K. Chaudhuri
David J. Tracy
Michael W. Helioff
Assignee (at issue)
GAF Corporation
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.