Granted Patent
Utility
US 4,339,557 · App. 06/183,454
Process for producing propylene-ethylene block copolymer
Inventors:
Masayoshi Hasuo, Yoshinori Suga, Kazuhisa Kojima, Masatoshi Suzuki
Patented Case
View Patent ↗
Granted: Jul 13, 1982
Filed: Sep 2, 1980
Inventors
Masayoshi Hasuo
Yoshinori Suga
Kazuhisa Kojima
Masatoshi Suzuki
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.