Granted Patent
Utility
US 4,383,890 · App. 06/239,480
Ceramic sheet and method for producing the same
Inventors:
Masayuki Oshima, Yasuhiko Matsui
Patented Case
View Patent ↗
Granted: May 17, 1983
Filed: Mar 2, 1981
Inventors
Masayuki Oshima
Yasuhiko Matsui
Assignees (at issue)
NITTETSU MINING CO., LTD.
Toyo Pulp 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.