(under subclass 69) Processes which include the step of causing a normally solid or liquid substance in either elemental or compound form to be changed into a gas or vapor; see Glossary.
SEE OR SEARCH CLASS
203, Distillation: Processes, Separatory, appropriate subclasses, especially
28+, for a process which includes a chemical reaction solely for the purpose of facilitating the isolation by distillation of a component of the original mixture. A process which includes vaporizing an impure mixture and then chemically treating the impure vapor to recover or separate therefrom a desired metal compound is classified in Class 423; see also reference to Class 203 in section III, Line and Search Notes.
