For China pcb manufacturer,what effects does the white residue on the PCB have on the three anti-paint coatings?

For the three anti-paint coating operation China pcb manufacturer, every time when they see some white spot residue on the board, China pcb manufacturer will show a very anxious expression. The three anti-paint is the last step in all the processes, and if the front step is not processed well, which will directly affect the subsequent process, the China pcb manufacturer of the three anti-paints silently think that board need to be washed, why not clean it completely clean. So what effect does the white residue on the PCB have on the three anti-paint coating?

Most of these white spots are flux residues, some crystals, dust, etc., and the flux is acidic. The residue will stay on the panel for a long time and will also reduce the protective effect of the three anti-paint.Where there is white residue, the paint film is also the easiest to fall off. First, it will affect the adhesion of the film. Over time, it will also corrode the solder joints and components of the board, affecting the reliability of the board. Even for no-clean flux, the ion residue should be controlled below 1.56ug.NaCl/m2 (J-STD-001 standard), and rosin is also required. The 123-level circuit board requires less than 200, 100, 40mg/cm2 respectively. If China pcb manufacturer say that the white liquid is from other processes, it is best to trace the root cause and ask the china pcb manufacturer to improve the craft and eliminate the source of the pollution.