Granted Patent
Utility
US 5,006,569 · App. 07/394,548
Density reduction in flexible polyurethane foams
Inventor:
Herman Stone
Patented Case
View Patent ↗
Granted: Apr 9, 1991
Filed: Aug 16, 1989
Inventor
Herman Stone
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.