Granted Patent
Utility
US 4,837,337 · App. 07/151,589
Process for producing pyrrolidone derivative
Inventors:
Yoshikazu Murao, Masao Miyake
Patented Case
View Patent ↗
Granted: Jun 6, 1989
Filed: Feb 3, 1988
Inventors
Yoshikazu Murao
Masao Miyake
Assignee (at issue)
Mitsubishi Chemical Industries, Ltd.
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.