Granted Patent
Utility
US 5,685,899 · App. 08/509,506
Process for conditioning kaolin clays prior to removing impurities
Inventors:
Joseph Allen Norris, Jorge L. Yordan
Patented Case
View Patent ↗
Granted: Nov 11, 1997
Filed: Jul 28, 1995
Inventors
Joseph Allen Norris
Jorge L. Yordan
Assignee (at issue)
Thiele Kaolin Company
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.