Granted Patent
Utility
US 6,451,109 · App. 09/830,119
Columnar crystals of 6-hydroxy-2-naphthoic acid and process for manufacturing the same
Inventors:
Ryuzo Ueno, Masaya Kitayama, Hiroyuki Kato, Ryoichi Otsuka
Patented Case
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Granted: Sep 17, 2002
Filed: Apr 24, 2001
Inventors
Ryuzo Ueno
Masaya Kitayama
Hiroyuki Kato
Ryoichi Otsuka
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.