Granted Patent
Utility
US 4,436,679 · App. 06/319,403
Method and apparatus for generating foamed thermoplastic materials
Inventor:
Thomas W. Winstead
Patented Case
View Patent ↗
Granted: Mar 13, 1984
Filed: Nov 9, 1981
Inventor
Thomas W. Winstead
Assignee (at issue)
Maryland Cup 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.