Granted Patent
Utility
US 4,495,250 · App. 06/523,593
Anion exchange resin of surface functional type and the process for producing the same
Inventors:
Takaharu Itagaki, Hidenaga Ouchi, Akihiro Shimura
Patented Case
View Patent ↗
Granted: Jan 22, 1985
Filed: Aug 16, 1983
Inventors
Takaharu Itagaki
Hidenaga Ouchi
Akihiro Shimura
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.