Patent ID: 7935642

Claim:
A method for calculating an amount of solution components to add to an advanced coating removal (ACR) stripping solution for a coating removal stripping bath to replenish and recover stripping potential wherein a chemical composition for the coating removal stripping bath includes a first compound selected from the group consisting of primary acids having a formula of H x AF 6 , a precursor thereof, and a mixture of said acid and said precursor; wherein A is selected from the group consisting of Si, Ge, Ti, Zr, Al, and Ga; and x is in a range from 1 to 6, inclusive; a second compound selected from the group consisting of phosphoric acid, nitric acid, sulfuric acid, hydrochloric acid, hydrofluoric acid, hydrobromic acid, hydriodic acid, acetic acid, perchloric acid, phosphorous acid, phosphinic acid, alkyl sulfonic acids, and mixtures thereof; and a third component of hydrochloric acid; the method comprising: measuring a starting density and a starting volume of the ACR stripping solution in the coating removal stripping bath; measuring the final density and final volume of the ACR stripping solution after use of the coating removal stripping bath; calculating an amount of a primary acid and an amount of fresh water to be added to the ACR stripping solution to rejuvenate the stripping effectiveness of the coating removal stripping bath.