As mentioned earlier, PCB printed circuit boards can use other colors besides green. To understand why people might choose different colors, it's important to understand what the color of the PCB actually is. The color of the printed circuit determines the color of the solder oil or solder mask. It consists of pigment-infused lacquer that protects traces of bare copper. One of the main functions of the solder mask is to prevent short circuits on the circuit board.

Typically, PCB color choices are made for aesthetic reasons, but some color choices also have functional reasons. For example, blue, the second most popular color for printed circuit boards, many designers have a good contrast between the color and the copper wire, making assembly and maintenance easier. Discover the blue solder mask used in LCDs. Red also provides high contrast between planes, traces, and spaces on a PCB board. Black is a color that is difficult to spot such problems. White is also hard to spot contrast. The color of the PCB board usually does not determine the quality of the PCB printed circuit board. However, there are some caveats when choosing a solder mask color. Commercial green solder mask is the only color available that can reliably produce 0.1 mm (4 mil) solder mask. Red, yellow and blue can reach 0.12mm, and black and white can only reach 0.15mm.