Granted Patent
Utility
US 4,808,733 · App. 07/135,216
Certain 4-oxo-3-benzoylvalerolactones and thiolactones
Inventors:
Christopher G. Knudsen, William J. Michaely, Donald R. James, Hsiao-Ling M. Chin
Patented Case
View Patent ↗
Granted: Feb 28, 1989
Filed: Dec 21, 1987
Inventors
Christopher G. Knudsen
William J. Michaely
Donald R. James
Hsiao-Ling M. Chin
Assignee (at issue)
Stauffer 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.