For those not familiar with printed circuit boards and how they’re made, there’s a common misconception that all PCBs are green. However, that actually is not the case. Printed circuit boards come in a variety of colors, and there are reasons why these different colors exist. Learn more about printed circuit board colors, variations, and what they mean.
Why are most printed circuit boards green?
While green still remains the most prominent color used for PCBs, other colors used include blue, red, yellow, white, black, and purple. There are reasons for each color, both functionally and aesthetically, which we’ll delve into in a moment. Green is by far the most common, and there are several good reasons why green is often used. The green color has been around for a very long time and has been the universal color code for PCBs. Green is one of the least fatiguing colors on the eyes, so if a designer is working on a green PCB for an extended amount of time, it’s considered the least straining to the eye. Green PCBs have higher contrast, making them suitable for identifying traces and residues quickly. The resources available to produce green printed circuit boards are widely available and easily accessible in large volumes. Since green is the color most people use, it facilitates mass production and lowers the price of the product cost.
Other colors used for PCBs
As mentioned previously, other colors besides green can be used for printed circuit boards. To understand why one may opt for different colors, it’s important to understand what exactly a PCB board color is. The color of a printed circuit defines the color of the solder oil or solder mask. It consists of lacquer infused with pigments that protect the traces of bare copper. One of the main functions of the solder mask is prevention against the short-circuiting of the circuit board.
Oftentimes, the color choice of a printed circuit board is aesthetics, but there are also functional reasons for certain color choices. Blue, the second most popular color for printed circuit boards, which many designers have good contrast between the color and the copper wires, making it simpler to assemble and do repairs. You’ll often find a blue solder mask used in LCDs. Red also offers high contrast between planes, traces, and spaces on a PCB. While black is a difficult color to see such issues, Apple is known for using black PCBs for their boards in the manufacture of iPhones and MacBooks. White is also very difficult to spot contrasts, though many designers state that tilting the PCB will allow better visibility for both black PCBs and white PCBs.
Does color dictate quality?
It’s commonly agreed that the color of a PCB does not typically dictate the quality of the printed circuit board. However, there are a few considerations when choosing a solder mask color. Commercial green solder mask is the only available color that can reliably produce solder mask dams of 0.1mm (4mil). Red, yellow, and blue can produce 0.12mm dams, and black and white which can only achieve 0.15mm.
Is it worth opting for different colors in PCBs?
Many designers prefer using printed circuit board colors other than green when creating printed circuit boards. Whether that choice is dictated by aesthetics, visibility, or other reasons, colored printed circuit boards continue to expand in electronics of all kinds. If the potential additional cost of a color variant is not a deterrent, there is no reason not to opt for a non-green PCB! When requesting a PCB quote, work with an experienced PCB company to help guide your purchase decision to ensure you’re getting the ideal printed circuit board for your needs.
