Testing and long‐term monitoring within printed circuit board cleaning technology
Purpose – The purpose of this paper is to present the development and implementation of a system of test methods for determining the contamination level in cleaning baths and using this system for long‐term monitoring in printed circuit board (PCB) production.Design/methodology/approach – A set of test methods was chosen that indicated the contamination of production cleaning baths in four chambers of an ultrasonic cleaning equipment filled with a commercial alkaline cleaner and isopropanol. By long‐term monitoring, the amount of mechanical impurities, residue‐on‐evaporation, pH and conductivity were measured. Depending on the contamination of the cleaning baths, the final contamination of PCB surfaces was predicted and the baths were replaced with fresh baths.Findings – A novel system for testing and monitoring the contamination of cleaning baths was developed and implemented. The sustainable compliance with the specification was assured in PCB production, thus, the final PCB contamination achieved was u...