Granted Patent
Utility
US 4,990,296 · App. 07/396,249
Welding of filled sintered polytetrafluoroethylene
Inventor:
Stefan Pitolaj
Patented Case
View Patent ↗
Granted: Feb 5, 1991
Filed: Aug 21, 1989
Inventor
Stefan Pitolaj
Assignee (at issue)
Garlock, Inc.
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.