Granted Patent
Utility
US 4,774,336 · App. 06/914,224
Process for preparing N-substituted piperazines from ethylene glycol and amines
Inventor:
Wei-Yang Su
Patented Case
View Patent ↗
Granted: Sep 27, 1988
Filed: Oct 2, 1986
Inventor
Wei-Yang Su
Assignee (at issue)
Texaco 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.