Granted Patent
Utility
US 4,338,197 · App. 06/246,434
Method and apparatus for the treatment of wastewater
Inventor:
David Bolton
Patented Case
View Patent ↗
Granted: Jul 6, 1982
Filed: Mar 23, 1981
Inventor
David Bolton
Assignee (at issue)
IMPERIAL CHEMICAL INDUSTRIES LIMITED
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.