Granted Patent
Utility
US 4,923,837 · App. 07/286,024
Hydrogenation catalyst
Inventors:
Hiroshi Fukuhara, Fujihisa Matsunaga, Yasushi Nakashima
Patented Case
View Patent ↗
Granted: May 8, 1990
Filed: Dec 19, 1988
Inventors
Hiroshi Fukuhara
Fujihisa Matsunaga
Yasushi Nakashima
Assignee (at issue)
Mitsui Petrochemical 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.