PCB Technical - Is there a difference in the ink color of the PCB circuit board?

Open an electronic product, there are usually several PCBs inside, and the PCB colors are various: green, blue, red, white, black, etc., will these different colors be distinguished by high or low? Today we will take a look at PCB inks.

The color of PCB is mainly the color of solder mask ink, and the more common ones on the market are green, blue, red, black, and white. As the name suggests, the role of solder mask is to prevent soldering. Usually, a layer of insulating solder mask ink is printed during PCB manufacturing, and the circuits and pads that do not need to be exposed are covered with solder mask ink to prevent unnecessary short circuits during soldering. It is not only beautiful, but also can protect the copper surface of the circuit from being oxidized. As for what color to use, it mainly depends on what product the PCB board is used for. For example, the aluminum substrate used in the LED panel light should use white solder mask. There are no special requirements for other products, and they generally use common green.

Blue PCB circuit board
The color of the ink depends on the ink manufacturer, and the same color will have different characteristics. The characteristics of the ink are mainly reflected in the following aspects:

Nickel-plated gold resistance: At present, many PCB surface treatments are nickel-plated gold, so the resistance to nickel-plated gold must be good.
High photosensitivity: The higher photosensitivity allows the ink to be cured quickly during curing.
Cavitation resistance: No bubbles or pinholes are generated during the process of spraying or printing ink curing.
High adhesion: adhesion affects the life of the ink, and high adhesion avoids falling off and lifting.
Heat resistance: Good heat resistance can protect the stability of high-power components PCB.
Halogen-free: The PCB production process has a certain impact on the environment. Lead-free and halogen-free will be the focus of PCB manufacturing in the future.
Smoke density: The lower the smoke density produced during use, the smaller the impact on the environment.
There is no difference in performance for different ink colors. As the electrical connection between components, PCB has no direct relationship between color and performance, and the difference in color will not affect the electrical properties. The performance of the PCB board is determined by factors such as materials and wiring design. However, during the PCB manufacturing process, the black solder mask is not very friendly to subsequent inspections. Since the black solder mask will cover the circuit illegible, it will cause certain difficulties for subsequent inspection and maintenance. In recent years, many designers will choose matte solder mask to make the PCB look very textured. The final color depends on where your product is used, and the color requirements are not high.