Granted Patent
Utility
US 4,874,518 · App. 07/287,650
Porous silica microspheres having a silanol enriched surface
Inventors:
Joseph J. Kirkland, Jurgen Kohler
Patented Case
View Patent ↗
Granted: Oct 17, 1989
Filed: Dec 21, 1988
Inventors
Joseph J. Kirkland
Jurgen Kohler
Assignee (at issue)
E.I. DU PONT DE NEMOURS AND 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.