After SMT assembly, wave soldering, or manual soldering processes, residues are often left on the PCB surface. Even when no-clean flux is used, residues may still pose risks in high-reliability applications, such as ionic contamination, leakage current, electrochemical migration, and corrosion. Therefore, PCB cleaning plays a critical role in high-end electronics manufacturing.
The main functions of PCB cleaning solution include: first, removing flux residues to prevent moisture absorption and long-term corrosion; second, eliminating solder paste debris and particulate contamination to improve surface cleanliness; third, reducing ionic contamination levels to enhance insulation performance and reliability; and fourth, providing a clean surface for subsequent processes such as conformal coating or final assembly.
Common types of PCB cleaning solutions in the industry include solvent-based cleaners, aqueous (water-based) cleaners, and semi-aqueous cleaners. Solvent-based cleaners offer high efficiency and fast evaporation, making them suitable for most SMT products. Water-based cleaners are more environmentally friendly but usually require dedicated cleaning equipment and drying processes. Semi-aqueous cleaners combine the advantages of both and are widely used in industrial electronics.
In production practice, PCB cleaning is typically performed using ultrasonic cleaning machines, spray cleaning systems, or manual wiping methods, followed by thorough drying to ensure no moisture remains on the board.
As electronic products continue to evolve toward higher density and greater reliability-especially in automotive electronics, medical devices, industrial control, and energy storage systems-the demand for high PCB cleanliness is increasing. Future PCB cleaning solutions will continue to develop toward low-VOC, environmentally friendly, high-compatibility, and low-residue formulations to better support advanced PCBA manufacturing.
