Granted Patent
Utility
US 4,571,437 · App. 06/516,857
Process for preparing p-aminophenol and alkyl substituted p-aminophenol
Inventors:
Douglas C. Caskey, Douglas W. Chapman
Patented Case
View Patent ↗
Granted: Feb 18, 1986
Filed: Jul 25, 1983
Inventors
Douglas C. Caskey
Douglas W. Chapman
Assignee (at issue)
MALLINCKRODT LLC
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.