Granted Patent
Utility
US 4,340,573 · App. 06/211,888
Preparation of zeolites
Inventors:
David E. W. Vaughan, Grant C. Edwards, Michael Barrett
Patented Case
View Patent ↗
Granted: Jul 20, 1982
Filed: Jan 9, 1980
Inventors
David E. W. Vaughan
Grant C. Edwards
Michael Barrett
Assignee (at issue)
W. R. Grace & Co.
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.