Granted Patent
Utility
US 5,217,660 · App. 07/724,006
Method for manufacturing expanded polystyrene foam components from used polystyrene materials
Inventor:
Kevin Howard
Patented Case
View Patent ↗
Granted: Jun 8, 1993
Filed: Jul 1, 1991
Inventor
Kevin Howard
Assignee (at issue)
Hewlett-Packard Company, L.P.
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.