Granted Patent
Utility
US 4,391,928 · App. 06/299,360
Opacifying polymeric particle and uses
Inventors:
Daniel F. Herman, Uno Kruse
Patented Case
View Patent ↗
Granted: Jul 5, 1983
Filed: Sep 4, 1981
Inventors
Daniel F. Herman
Uno Kruse
Assignee (at issue)
NL Industries, Inc.
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.