Granted Patent
Utility
US 4,380,608 · App. 06/347,425
Process for producing propylene-ethylene block copolymer
Inventors:
Masayoshi Hasuo, Yoshinori Suga, Hisashi Kitada, Yasuo Maruyama, Junichi Gotoh
Patented Case
View Patent ↗
Granted: Apr 19, 1983
Filed: Feb 10, 1982
Inventors
Masayoshi Hasuo
Yoshinori Suga
Hisashi Kitada
Yasuo Maruyama
Junichi Gotoh
Assignee (at issue)
Mitsubishi Chemical 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.