Granted Patent
Utility
US 4,329,493 · App. 06/160,541
Process for producing terephthalic acid
Inventors:
Hiroshi Hashizume, Yoshiaki Izumisawa
Patented Case
View Patent ↗
Granted: May 11, 1982
Filed: Jun 18, 1980
Inventors
Hiroshi Hashizume
Yoshiaki Izumisawa
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.