Granted Patent
Utility
US 4,131,542 · App. 05/817,060
Spray dried silica for chromatography
Inventors:
Horacio E. Bergna, Joseph J. Kirkland
Patented Case
View Patent ↗
Granted: Dec 26, 1978
Filed: Jul 19, 1977
Inventors
Horacio E. Bergna
Joseph J. Kirkland
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.