Granted Patent
Utility
US 4,311,820 · App. 06/118,356
Homopolymers and copolymers of vinyl ethers of polyalkylpiperidinols and their use as stabilizers for plastics
Inventor:
Erwin Nikles
Patented Case
View Patent ↗
Granted: Jan 19, 1982
Filed: Feb 4, 1980
Inventor
Erwin Nikles
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.