Granted Patent
Utility
US 4,657,715 · App. 06/687,680
Process for preparing smooth skinned extruded foams with water-organic blowing agent
Inventors:
Donald W. Myers, Dennis P. O'Brien
Patented Case
View Patent ↗
Granted: Apr 14, 1987
Filed: Dec 31, 1984
Inventors
Donald W. Myers
Dennis P. O'Brien
Assignee (at issue)
Mobil Oil 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.