Granted Patent
Utility
US 4,596,593 · App. 06/612,805
Urea-formaldehyde condensate-based slow release nitrogen fertilizer and process for producing same
Inventors:
Shunsuke Tazawa, Katsuhiko Kurihara, Yuzuru Kawagoe, Seinosuke Ando, Kazuhiko Kon
Patented Case
View Patent ↗
Granted: Jun 24, 1986
Filed: May 22, 1984
Inventors
Shunsuke Tazawa
Katsuhiko Kurihara
Yuzuru Kawagoe
Seinosuke Ando
Kazuhiko Kon
Assignee (at issue)
Nitto Chemical Industry 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.