Granted Patent
Utility
US 4,350,773 · App. 06/280,522
Weakly acidic cation exchange resin and process for producing same
Inventors:
Takaharu Itagaki, Hidenaga Ouchi
Patented Case
View Patent ↗
Granted: Sep 21, 1982
Filed: Jul 6, 1981
Inventors
Takaharu Itagaki
Hidenaga Ouchi
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.