Granted Patent
Utility
US 5,990,262 · App. 08/875,194
Process for producing polycarbonates
Inventors:
Akihiro Shishikura, Masahiro Takahashi, Seiji Takahashi, Noriyuki Kunishi, Hiroaki Motegi
Patented Case
View Patent ↗
Granted: Nov 23, 1999
Filed: Sep 15, 1997
Inventors
Akihiro Shishikura
Masahiro Takahashi
Seiji Takahashi
Noriyuki Kunishi
Hiroaki Motegi
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.