Granted Patent
Utility
US 4,906,672 · App. 07/226,145
Blowing agents for polyurethane foam
Inventors:
Herman Stone, Steve Lichvar, Charles W. Bredbenner, Richard B. Rupp, Elmer Minnich
Patented Case
View Patent ↗
Granted: Mar 6, 1990
Filed: Jul 29, 1988
Inventors
Herman Stone
Steve Lichvar
Charles W. Bredbenner
Richard B. Rupp
Elmer Minnich
Assignee (at issue)
PMC, 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.