Abstract: A neutralization process is provided for neutralizing chloride ions in etched via holes in multilayer printed circuit boards. The process comprises two dip operations of the board in a Neutra-Clean and water solution which is continuously re-circulated. This is followed by subjecting the board to a heated de-ionized cascaded water feed, an ambient overflow de-ionized water rinse, and conveyorized air drying. The Neutra-Clean solution has the ability to penetrate down to the bottom of the via hole and to attract the free chloride ions from the etchant residue. The de-ionized water feed and rinse steps rinse out and remove the Neutra-Clean solution and any residuals formed by chemical reaction.