AQUEOUS SOLUTION AND METHOD FOR REMOVING IONIC CONTAMINANTS FROM THE SURFACE OF A WORKPIECE

摘要

To reduce ionic contaminants on printed circuit boards that are at least partially covered with a solder resist mask and are provided with top layers on the copper structures, an aqueous cleaning solution is used, which contains at least one ethanolamine compound and/or the salt thereof, at least one alcoholic solvent and, at need, at least one guanidine compound and/or the salt thereof.