PCB Technical - What is the situation of patina on the pcb board.

There are many types of electronic products, and consumers have a lot of room to choose. If products are of poor quality and short use time, they are easily eliminated by the market. Only by grasping the quality of products can they exert greater market competitiveness, because almost all electronic products will use To the PCB board, more and more electronic product manufacturers are paying special attention to the demand for three anti-paints, the purpose is to protect the circuit board, components and printed wires from damage, so as to ensure the service life.

So what if the PCB board is not coated with three anti-paint? Let me tell you a few aspects, please understand.

1. Patina phenomenon

Patina is also called patina, so how does PCB patina come from? First of all, we need to know the reasons for the appearance of patina onPCB circuit boards. Moisture is the most common and destructive main factor to PCB circuit boards.

Therefore, if the PCB circuit board is kept in a humid environment for a long time, coupled with the action of oxygen and carbon dioxide, the copper on the PCB circuit board will begin to chemically react to rust and produce patina, which will eventually cause the circuit board to fail to work. The solution is to use PCB three-proof paint and electric anti-glue.

2. Leakage or short circuit phenomenon

How did the leakage phenomenon come from? Since there is no protection on the electrical circuit, after a long time accumulated with dust, because the dust is easy to absorb moisture, the resistance of the dust with moisture will be reduced, causing local leakage of the wire, and it is easy to cause the control circuit to work abnormally or even generate heat.

For example, the computer that we often use for a long time has been abnormally turned on. After cleaning the circuit board, it can be turned on normally. It is because the circuit board is covered with too much dust and the circuit board is not protected by the three-proof paint, which is a serious situation. Next, cleaning is useless, only replace the host directly. Therefore, the solution to prevent leakage or short circuit in the product is to use PCB three-proof paint and electric anti-glue.

3. Fingerprints or sweat influence

Almost every aspect of PCB manufacturing involves manual operations, and there is a greater risk of contamination, especially sweaty hands. We can understand what ingredients are in sweat fingerprints, such as moisture, inorganic salts, fatty oils, and some who like makeup. There are hazards such as cosmetics, skin care products, etc., remaining in components, component pins, soldering wires, etc., coupled with the effect of the external environment, components and components will appear on the surface of the circuit board after a short period of 2 or 3 months. The pins are corroded and broken and so on. Therefore, after the PCB board is manufactured, the surface of the board is cleaned and the three-proof paint is sprayed to ensure that all aspects of the PCB board used on the product in the subsequent assembly process are working properly. Therefore, to solve the hazards caused by fingerprints, it is better to use the PCB three-proof paint, Electric anti-glue.

Therefore, if the PCB board is not coated with three-proof paint and electrical anti-glue, and waits until the market is returned, it is slightly repaired and reworked, and seriously scrapped, the cost of the loss is much higher than the cost of using the three-proof paint, because of environmental changes and the areas where the product is used. It is not the same. Without the use of three-proof paint, it is unavoidable to prevent the PCB contacting environmentally hazardous substances, such as heavy humidity in the south, especially during the regain period, heavy salt spray at the seaside, heavy chemical damage and heavy chemical damage.