Granted Patent
Utility
US 4,440,577 · App. 06/415,018
Polyhydroxy polyphenyl compounds as additives for cementitious materials
Inventors:
Alphonso W. Marcellis, Grannis S. Johnson
Patented Case
View Patent ↗
Granted: Apr 3, 1984
Filed: Sep 7, 1982
Inventors
Alphonso W. Marcellis
Grannis S. Johnson
Assignee (at issue)
Diamond Shamrock 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.