Granted Patent
Utility
US 4,461,634 · App. 06/368,709
Separation of gas mixtures by partial condensation
Inventors:
Melvyn Duckett, Gregory J. Ashton, David Salisbury
Patented Case
View Patent ↗
Granted: Jul 24, 1984
Filed: Apr 15, 1982
Inventors
Melvyn Duckett
Gregory J. Ashton
David Salisbury
Assignee (at issue)
Petrocarbon Developments 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.