Granted Patent
Utility
US 5,004,839 · App. 07/508,454
Preparation of unsaturated ketones from acetone and paraformaldehyde (II)
Inventors:
Joseph Pugach, Jeffrey S. Salek
Patented Case
View Patent ↗
Granted: Apr 2, 1991
Filed: Apr 13, 1990
Inventors
Joseph Pugach
Jeffrey S. Salek
Assignee (at issue)
Aristech 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.