Granted Patent
Utility
US 4,146,574 · App. 05/797,771
Process for preparing heteropoly-acids
Inventors:
Takeru Onoda, Masayuki Otake
Patented Case
View Patent ↗
Granted: Mar 27, 1979
Filed: May 17, 1977
Inventors
Takeru Onoda
Masayuki Otake
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.