Granted Patent
Utility
US 4,824,913 · App. 07/046,382
Process for preparing water-soluble polymer
Inventors:
Yoshikazu Murao, Shigeru Sawayama, Kohichi Satoh
Patented Case
View Patent ↗
Granted: Apr 25, 1989
Filed: May 6, 1987
Inventors
Yoshikazu Murao
Shigeru Sawayama
Kohichi Satoh
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.