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Colors of a Blank Circuit Board

A printed circuit board is used as a basis for attaching electronic components to each other. They are usually green. This color does not indicate anything specific about the circuit board, but is the result of the process in which the circuit board is made. Other colors can be used instead, but these will incur additional costs.

Board construction
- A standard circuit board is 1.6mm thick and made of fibreglass-resin laminate or slightly cheaper phenolic. Copper is added to the board based on a hand-drawn design in basic circuits or a computer-based design for more complex ones. This is the basis of the circuits that will be made, as electrical signals are transferred along the copper. Individual copper lines are either placed on the board individually or a single sheet of copper can be placed on the board and the excess copper stripped away.
Why green?
- A soldermask is added to the top of the circuit board. This is a plastic substance that protects the copper lines from touching each other when components are soldered together. If it is not used, solder can join two copper lines and divert the electrical current, resulting in a short circuit. The solder mask plastic is traditionally green, which is why circuit boards tend to be green.
Why not?
- The color of a circuit board can be changed for a number of reasons. Boards can be colored differently for branding purposes, to differentiate between versions of the same circuit board or to indicate flexibility to customers by offering custom designs. Jody Williams, new business development manager at Taiyo America, argues in his article ̶0;Soldermask: it's not just green anymore̶1; that introducing a striking new color early into a circuit board̵7;s design will convince customers that the manufacturer is willing to customize parts for their client and ensure brand loyalty for years to come.
The drawbacks
- Generally speaking, the color of a circuit board does not matter, unless components are being placed by computer software that operates by optical alignment. In this instance a component will be placed based on a visual marker on the board. This is a problem with black, yellow and white boards because it is difficult for ultraviolet light to penetrate the colored soldermask to identify the component location below. For the best results, a clear soldermask should be used in these instances.

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