Granted Patent
Utility
US 4,678,684 · App. 06/842,596
Method for impregnating a thermoplastic polymer
Inventor:
Michael L. Sand
Patented Case
View Patent ↗
Granted: Jul 7, 1987
Filed: Mar 21, 1986
Inventor
Michael L. Sand
Assignee (at issue)
HERCULES LLC
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.