Granted Patent
Utility
US 5,643,358 · App. 08/334,269
Crystalline hydrated layered sodium and potassium silicates and method of producing same
Inventors:
Eric Borgstedt, Raymond P. Denkewicz, Jr.
Patented Case
View Patent ↗
Granted: Jul 1, 1997
Filed: Nov 3, 1994
Inventors
Eric Borgstedt
Raymond P. Denkewicz, Jr.
Assignee (at issue)
PQ Corporation
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.