PCB News - What are the effects of PCB painting? Most people don’t even know

What are the effects of PCB painting? Most people don’t even know

Strictly speaking, PCB manufacturing is not simple. In addition, our common PCB boards are not only single-layer boards, but also multi-layer boards. Therefore, the processing technology of manufacturing multi-layer boards is more complicated and the cost is higher; in general, Said, PCB design and production is a complex science, all need professional PCB engineers to design; when you buy all the large and small circuit boards on the market, these circuit boards in the use process, because they will be in different In the environment, such as chemical substances (fuel, coolant, etc.), vibration, high dust, salt spray, humidity and high temperature, etc., it is an extreme test for the circuit board itself. In these environments, the circuit board is easy to produce Softening, deformation, mildew, corrosion and other problems, which lead to circuit board circuit failure.

Therefore, there is a substance called three-proof paint that plays a very important role. The three-proof refers to moisture-proof, salt-fog and mildew-proof. It is a specially formulated paint that coats the surface of the PCB with the three-proof paint. A layer of protective film with three protections is formed. The protective film can protect the circuit from damage in the environment of chemical, vibration, high dust, salt spray, humidity and high temperature, improve the reliability of the circuit board, and increase its safety factor. In addition, because the three-proof paint can prevent leakage, it allows higher power and closer printed board spacing, which can meet the purpose of component miniaturization.

In addition, there is copper on each layer on both sides of the PCB. In the production of PCB, no matter whether the copper layer is manufactured by the additive method or the subtractive method, a smooth and unprotected surface will be obtained in the end. Although the chemical properties of copper are not as active as aluminum, iron, magnesium, etc., in the presence of water, pure copper is easily oxidized in contact with oxygen; because oxygen and water vapor exist in the air, the surface of pure copper is exposed to air Oxidation reaction will occur soon. Because the thickness of the copper layer in the PCB is very thin, the oxidized copper will become a poor conductor of electricity, which will greatly damage the electrical performance of the entire PCB.

In order to prevent the oxidation of copper, to separate the soldered and non-soldered parts of the PCB during soldering, and to protect the surface of the PCB, a solder mask is also used. This kind of paint can be easily painted on the surface of the PCB to form a protective layer with a certain thickness and block the contact between copper and air. The PCB factory has always adhered to the exquisite technical force, sophisticated production equipment, perfect testing methods, product quality higher than the industry standard, and warm and thoughtful service, which has won praise and welcome from global merchants and users.