Granted Patent
Utility
US 5,354,517 · App. 08/054,033
Process for the preparation of substrates for optical disk
Inventors:
Kazuyuki Yamasaki, Takehiko Kitamura
Patented Case
View Patent ↗
Granted: Oct 11, 1994
Filed: Apr 27, 1993
Inventors
Kazuyuki Yamasaki
Takehiko Kitamura
Assignees (at issue)
Mitsui Petrochemical Industries, Ltd.
SUMITOMO HEAVY 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.