Granted Patent
Utility
US 4,293,707 · App. 06/045,549
Process for preparing trichlorophenoxy alkanoic acid and hydrolyzable derivatives thereof free of chlorinated dibenzo-p-dioxins
Inventors:
Sidney B. Richter, William S. Grove
Patented Case
View Patent ↗
Granted: Oct 6, 1981
Filed: Jun 4, 1979
Inventors
Sidney B. Richter
William S. Grove
Assignee (at issue)
PPG Industries, 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.