Granted Patent
Utility
US 4,902,413 · App. 07/315,297
Organic-based porous microspheres for HPLC
Inventors:
Richard W. Stout, Henry J. Leibu
Patented Case
View Patent ↗
Granted: Feb 20, 1990
Filed: Feb 24, 1989
Inventors
Richard W. Stout
Henry J. Leibu
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.