Granted Patent
Utility
US 4,861,443 · App. 07/209,763
Process for preparing 4,4'-isopropylidenedithio-bis-(2,6-di-tertiarybutylphenol) by electrocatalysis
Inventor:
Richard M. Van Effen
Patented Case
View Patent ↗
Granted: Aug 29, 1989
Filed: Jun 22, 1988
Inventor
Richard M. Van Effen
Assignee (at issue)
Merrell Dow Pharmaceuticals 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.