Granted Patent
Utility
US 4,238,438 · App. 06/008,290
Hardboard with smooth, dense surface and method
Inventors:
Gerald F. Laughinghouse, Donald B. Gibson
Patented Case
View Patent ↗
Granted: Dec 9, 1980
Filed: Feb 1, 1979
Inventors
Gerald F. Laughinghouse
Donald B. Gibson
Assignee (at issue)
Champion International Corporation Limited
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.