Granted Patent
Utility
US 4,806,573 · App. 07/209,760
Polyimide foam precursor and its use in reinforcing open-cell materials
Inventor:
Kyu-Wang Lee
Patented Case
View Patent ↗
Granted: Feb 21, 1989
Filed: Jun 22, 1988
Inventor
Kyu-Wang Lee
Assignee (at issue)
Hexcel Corporation
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.