Method and electrolyte for anodizing valve metals to high voltage

摘要

A method of anodizing valve metals with a borate polyester solution formed by the combining 2-methyl-1,3-propane diol and boric acid and heating to about 130 to about 160° C. The heating drives off water produced by esterification. A substrate is immersed in the borate polyester electrolyte solution at a temperature of about 25° C. to about 85° C. and an anodizing voltage is applied.