Granted Patent
Utility
US 4,401,633 · App. 06/343,647
Two step process for the preparation of zeolite A by hydrothermal treatment of heulandite
Inventor:
Hsiang-Ning Sun
Patented Case
View Patent ↗
Granted: Aug 30, 1983
Filed: Jan 28, 1982
Inventor
Hsiang-Ning Sun
Assignee (at issue)
Atlantic Richfield 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.