Granted Patent
Utility
US 6,575,438 · App. 09/878,909
Stepped downcomer apparatus and vapor-liquid contact apparatus with same
Inventors:
Dale E. Nutter, Mark W. Pilling, Christina J. Campbell
Patented Case
View Patent ↗
Granted: Jun 10, 2003
Filed: Jun 13, 2001
Inventors
Dale E. Nutter
Mark W. Pilling
Christina J. Campbell
Assignee (at issue)
Sulzer Chemtech USA, Inc.
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.