Granted Patent
Utility
US 4,883,855 · App. 07/299,291
Ethylenically unsaturated polyether sulfone or polyether ketone copolymer
Inventor:
Friedrich Stockinger
Patented Case
View Patent ↗
Granted: Nov 28, 1989
Filed: Jan 23, 1989
Inventor
Friedrich Stockinger
Assignee (at issue)
Ciba-Geigy
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.