Granted Patent
Utility
US 5,473,033 · App. 08/424,749
Water-soluble cationic copolymers and their use as drainage retention aids in papermaking processes
Inventors:
Lawrence L. Kuo, Roger Yiming Leung, Kenneth S. Williams
Patented Case
View Patent ↗
Granted: Dec 5, 1995
Filed: Apr 18, 1995
Inventors
Lawrence L. Kuo
Roger Yiming Leung
Kenneth S. Williams
Assignee (at issue)
W.R. Grace & Co. Conn.
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.