New method of water cleaning for circuit substrate

A water-soluble flux with characteristics equivalent to those of rosin flux was developed by improving the activator and rheological modifier. The flux paste and specially developed cleaning equipment are described. Cleaning using the solder paste and the developed cleaning equipment was used on on-board power supply products. These products passed 1500 h of temperature, humidity, and bias testing, showing that this method combining the water-soluble paste and the cleaning equipment can provide the same reliability as processing by the conventional cleaning method using rosin flux and solvent.<
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