Granted Patent
Utility
US 4,376,847 · App. 06/252,325
Process for the production of styrene polymers
Inventors:
Tetsuyuki Matsubara, Norifumi Ito, Yuzuru Ishida, Mune Iwamoto
Patented Case
View Patent ↗
Granted: Mar 15, 1983
Filed: Apr 9, 1981
Inventors
Tetsuyuki Matsubara
Norifumi Ito
Yuzuru Ishida
Mune Iwamoto
Assignee (at issue)
Mitsui Toatsu Chemicals, Incorporated
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.