Granted Patent
Utility
US 5,919,645 · App. 07/682,923
Method for the direct determination of the toxicity of particulate solids
Inventors:
Ker-Kong Tung, Charles Walbourn, Grace Scheibner
Patented Case
View Patent ↗
Granted: Jul 6, 1999
Filed: Apr 9, 1991
Inventors
Ker-Kong Tung
Charles Walbourn
Grace Scheibner
Assignee (at issue)
Azur Environmental
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.