Granted Patent
Utility
US 5,155,152 · App. 07/496,380
Substitute aminopyrroles as stabilizers for chlorine-containing polymers
Inventors:
Wolfgang Wehner, Hermann O. Wirth
Patented Case
View Patent ↗
Granted: Oct 13, 1992
Filed: Mar 19, 1990
Inventors
Wolfgang Wehner
Hermann O. Wirth
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.