Granted Patent
Utility
US 4,885,501 · App. 07/174,660
Blackening of non iron-based flat tensioned foil shadow masks
Inventor:
Hua-Sou Tong
Patented Case
View Patent ↗
Granted: Dec 5, 1989
Filed: Mar 29, 1988
Inventor
Hua-Sou Tong
Assignee (at issue)
Zenith Electronics LLC
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.