Granted Patent
Utility
US 5,391,661 · App. 07/965,290
Process for producing a styrenic polymer and a catalyst for use therein
Inventors:
Shoji Naganuma, Masami Watanabe, Norio Tomotsu
Patented Case
View Patent ↗
Granted: Feb 21, 1995
Filed: Feb 2, 1993
Inventors
Shoji Naganuma
Masami Watanabe
Norio Tomotsu
Assignee (at issue)
IDEMITSU KOSAN 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.