Granted Patent
Utility
US 5,650,480 · App. 08/569,131
Process for preparing polycarbonate
Inventors:
Ryozo Okumura, Shigeki Kuze, Seiji Takahashi
Patented Case
View Patent ↗
Granted: Jul 22, 1997
Filed: Jan 11, 1996
Inventors
Ryozo Okumura
Shigeki Kuze
Seiji Takahashi
Assignee (at issue)
Idemitsu Petrochemical 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.