At present, the common colors of PCB circuit boards in the market are green, black, blue, yellow, purple, red, and brown, and recently white and pink PCBs have also appeared.

　　So, why do PCB circuit boards have different colors? Have you noticed that most circuit boards are green, while other colors are rare? Why is this? Next, the editor of the circuit board manufacturer will spread a wave of knowledge about circuit boards to everyone~

　　In the production of PCB boards, the final surface of the copper layer is smooth and unprotected, whether it is additive or subtractive. Although the chemical properties of copper are not as good as those of aluminum, iron, and magnesium, pure copper is prone to oxidation under water conditions when in contact with oxygen. However, the thickness of the copper layer in PCB circuit boards is very thin, and the oxidized copper can become a poor conductor of electricity, greatly damaging the electrical performance of the entire PCB.

　　In order to prevent copper oxidation, the welded and non welded parts of the PCB are separated to protect the surface of the PCB circuit board. Design engineers will apply a special coating on the surface of the PCB circuit board to form a certain thickness of protective layer, blocking the contact between copper and air. This coating is called a solder mask layer and the material used is solder mask paint. For the convenience of maintenance and manufacturing, PCBs usually require printing small text on the board. Therefore, engineers added various colors to the solder mask, ultimately forming a "colorful" circuit board.