Granted Patent
Utility
US 6,740,302 · App. 10/168,869
Method for producing high-purity sulphuric acid
Inventors:
Martin Hostalek, Werner Buttner, Rolf Hafner, Chih-Peng Lu, Ching-Jung Kan, Ekkehart Seitz, Ernst Friedel
Patented Case
View Patent ↗
Granted: May 25, 2004
Filed: Jun 26, 2002
Inventors
Martin Hostalek
Werner Buttner
Rolf Hafner
Chih-Peng Lu
Ching-Jung Kan
Ekkehart Seitz
Ernst Friedel
Assignee (at issue)
Merck Patent GmbH
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.