Granted Patent
Utility
US 5,116,466 · App. 07/786,857
Propylene oxide purification by extractive distillation
Inventors:
Edward T. Marquis, George P. Speranza, Yu-Hwa E. Sheu, William K. Culbreth, III, David G. Pottratz
Patented Case
View Patent ↗
Granted: May 26, 1992
Filed: Nov 1, 1991
Inventors
Edward T. Marquis
George P. Speranza
Yu-Hwa E. Sheu
William K. Culbreth, III
David G. Pottratz
Assignee (at issue)
Texaco Chemical 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.