Granted Patent
Utility
US 4,631,180 · App. 06/777,762
Process for producing carbon black
Inventors:
Syushichi Yoshimura, Hiromu Kobayashi, Yoshikazu Toyonaga, Hozo Yamazaki, Masanori Karatsu
Patented Case
View Patent ↗
Granted: Dec 23, 1986
Filed: Sep 19, 1985
Inventors
Syushichi Yoshimura
Hiromu Kobayashi
Yoshikazu Toyonaga
Hozo Yamazaki
Masanori Karatsu
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.