Granted Patent
Utility
US 4,248,795 · App. 05/767,488
Preparation of organic sulfone compounds
Inventor:
John K. Chan
Patented Case
View Patent ↗
Granted: Feb 3, 1981
Filed: Feb 10, 1977
Inventor
John K. Chan
Assignee (at issue)
Union Carbide Corporation
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.