Granted Patent
Utility
US 6,489,519 · App. 09/696,205
Process for removal of impurities from phenol by means of at least one acid catalyst
Inventors:
Heinrich van Barneveld, Otto Gerlich, Wilfried Jordan, Otto Schnurr, Hugo H. J. M. Liefooche
Patented Case
View Patent ↗
Granted: Dec 3, 2002
Filed: Oct 26, 2000
Inventors
Heinrich van Barneveld
Otto Gerlich
Wilfried Jordan
Otto Schnurr
Hugo H. J. M. Liefooche
Assignee (at issue)
Phenolchemie GmbH & Co. KG
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.