Granted Patent
Utility
US 4,537,820 · App. 06/547,669
Insulation board and process of making
Inventors:
Jeffert John Nowobilski, William J. Owens
Patented Case
View Patent ↗
Granted: Aug 27, 1985
Filed: Nov 1, 1983
Inventors
Jeffert John Nowobilski
William J. Owens
Assignee (at issue)
Union Carbide 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.