Granted Patent
Utility
US 6,607,578 · App. 09/990,179
Continuous vacuum refining method of molten metal and apparatus thereof
Inventors:
Mitsuhiro Otaki, Kensuke Mori
Patented Case
View Patent ↗
Granted: Aug 19, 2003
Filed: Nov 21, 2001
Inventors
Mitsuhiro Otaki
Kensuke Mori
Assignees (at issue)
KOBE STEEL, LTD.
Showa Denko K.K.
Sky Aluminium Co., Ltd.
NIPPON LIGHT METAL COMPANY, LTD.
FURUKAWA ELECTRIC CO., LTD.
MITSUBISHI ALUMINUM CO., 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.