Granted Patent
Utility
US 4,841,057 · App. 07/143,366
Cyclic imido anthraquinone compounds
Inventors:
Konoe Miura, Tetsuo Ozawa, Seigo Okumura, Shinji Kubo
Patented Case
View Patent ↗
Granted: Jun 20, 1989
Filed: Jan 12, 1988
Inventors
Konoe Miura
Tetsuo Ozawa
Seigo Okumura
Shinji Kubo
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.