Granted Patent
Utility
US 4,870,138 · App. 06/852,604
Semi-interpenetrating polymer networks
Inventor:
James A. Wrezel
Patented Case
View Patent ↗
Granted: Sep 26, 1989
Filed: Apr 16, 1986
Inventor
James A. Wrezel
Assignee (at issue)
AlliedSignal, 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.