Granted Patent
Utility
US 5,847,233 · App. 08/975,189
Naphthol derivatives and process for producing the same
Inventors:
Ryuzo Ueno, Shigeru Ito, Kenji Minami, Masaya Kitayama
Patented Case
View Patent ↗
Granted: Dec 8, 1998
Filed: Nov 20, 1997
Inventors
Ryuzo Ueno
Shigeru Ito
Kenji Minami
Masaya Kitayama
Assignee (at issue)
Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
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.