Granted Patent
Utility
US 5,266,296 · App. 07/644,213
Cocurrent flow process for the manufacture of sodium sulfite and bisulfite solutions
Inventors:
Walter H. Bortle, Jr., Samuel L. Bean, Mark D. Dulik
Patented Case
View Patent ↗
Granted: Nov 30, 1993
Filed: Jan 22, 1991
Inventors
Walter H. Bortle, Jr.
Samuel L. Bean
Mark D. Dulik
Assignee (at issue)
General Chemical Company
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.