Granted Patent
Utility
US 4,863,838 · App. 07/188,647
Direct positive type light-sensitive silver halide photographic materials
Inventors:
Keiji Ogi, Yasuo Tosaka
Patented Case
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Granted: Sep 5, 1989
Filed: May 2, 1988
Inventors
Keiji Ogi
Yasuo Tosaka
Assignee (at issue)
Konishiroku Photo 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.