.~ With chemically reactive treatment of glass preform {4}
31
.~.~ By etching or leaching
DEFINITION
Classification: 65/31
(under subclass 30) Processes in which the chemical treatment includes use of a chemical reagent to remove a portion or constituent of the glass.
SEE OR SEARCH CLASS
216, Etching a Substrate: Processes, for etching of glass materials by either chemical etching or physical solvation wherein a glass manufacturing step is not employed.
427, Coating Processes,
299+, for processes of coating combined with a pretreatment of the base.
