HASL Precleaner SLTM is a powerful, non-foaming, free rinsing, alkaline cleaner specifically designed to clean copper prior to HASL or alternative finishes. It will remove solder mask developer scum, oven baked oxidation and residues, fingerprints, and oils. HASL Precleaner SLTM will not etch copper nor will it damage the. HASL Precleaner SLTM can be used in conjunction with a light microetch or acid cleaner. If an acid cleaner is used, MicroCleanTM ZE is preferred. If a microetch is used, much lower levels of metal removal are fully acceptable, thus minimizing costs and reject rate. Because of the potent cleaning agents that destroy organo-metallic compounds (such as insoluble copper/soldermask compounds) present on the copper surfaces, use of HASL Precleaner SLTM will reduce the requirement for a second pass through the HASL.