Granted Patent
Utility
US 4,931,146 · App. 07/329,867
Process for obtaining high-purity bisphenol A
Inventors:
Shigeru Iimuro, Yoshio Morimoto, Takashi Kitamura
Patented Case
View Patent ↗
Granted: Jun 5, 1990
Filed: Mar 28, 1989
Inventors
Shigeru Iimuro
Yoshio Morimoto
Takashi Kitamura
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.