What is the circuit board three anti-paint repair?

three anti-paint repair

What is the circuit board three anti-paint repair? Coating three anti-paint is usually the last step in PCB assembly. However, when tested, the electronic components may be defective and three anti-paint coatings need to be repaired. Therefore, it is generally referred to as board three anti-paint repair. How did you do it?

For electronic components used in harsh environments, the application of three anti-paint can provide various protections for the circuit board: moisture proof, mildew proof, dustproof, insulation, greatly reducing the growth of dendrites, releasing stress and so on. Three anti-paints make electronic components more durable, improve the reliability of electronic devices, and reduce warranty costs.

When the board needs to be reworked, the expensive components on the board can be removed separately and the remaining parts can be discarded. But the more common method is to remove all or part of the protective film on the board and replace the damaged parts one by one. When removing the three anti-paint protective film, make sure that the substrate, other electronic components, and the structure near the service location are not damaged. The protective film removal method mainly includes: using a chemical solvent, micro-grinding, mechanical methods, and desoldering through a protective film.

The use of a chemical solvent is a common method for removing a three-coat protective film, and the key is the chemical nature of the protective film to be removed and the chemical nature of the specific solvent. Micro-grinding is the use of high-speed particles ejected from a nozzle to "grind" three anti-paint protective films on the board. The mechanical method is a particularly easy way to remove the three anti-paint protective film. Desoldering through the protective film first opens the discharge hole in the protective film to allow the molten solder to be discharged.