Granted Patent
Utility
US 4,248,617 · App. 06/016,801
Process for producing granular basic phosphate fertilizer
Inventors:
Seiichi Kamo, Tetzuo Watanabe, Kiyoshi Nakayama
Patented Case
View Patent ↗
Granted: Feb 3, 1981
Filed: Mar 2, 1979
Inventors
Seiichi Kamo
Tetzuo Watanabe
Kiyoshi Nakayama
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.