Printed circuit board is basically composed of pad, via, solder mask, silkscreen layer, copper circuit and various components. Copper is a relatively active metal. It is easy to react with oxygen in the air. The copper circuit of PCB is generally very thin, with a thickness of only tens of microns. After oxidation reaction, the poor conductor will damage the electrical performance of PCB. In order to prevent copper oxidation, to separate the soldered and non soldered parts of PCB during soldering, and to protect the surface layer of PCB, engineers invented a special coating.The coating can be easily applied on the PCB surface to form a protective layer with a certain thickness and block the contact between copper and air.This coating is called solder mask and is made of solder resist paint.

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We can find that most of the common circuit boards are green. Why?

In fact, PCB is not necessarily green. It depends on what color the designer wants to make it.

Viewpoint 1

In school, the teacher will tell you that if you read and do homework for a long time, your eyes are tired. You can have a look at green things, which can protect your eyesight.Therefore, green is selected because green is less irritating to the eyes, the production and maintenance personnel will not be prone to eye fatigue when staring at the PCB board for a long time, and it will cause little damage to the eyes.

Point 2

Because the most commonly used color is green, the factory has the most spare green paint, with more demand, larger shipment volume, and natural cutting cost. Therefore, the cost of using green paint is relatively low.

Point 3

Green ink can achieve smaller error, smaller area, can achieve higher accuracy.

The above is the technical documents of an ink supplier. From the technical documents, we can see that green, red and blue have higher design accuracy than other colors.

From the solar ink product characteristics table, we can find that green ink than other colors of ink, has better characteristics, especially plug hole characteristics.

Why do some companies increase the price to make white and black PCB?

Black and white can be helpful in some special occasions. For example, most LED panels use black characters on white background. The reason is that the white one reflects light and absorbs less heat.

Black ones, like some 5050 RGB bulbs, use black ones.The advantage is to reduce the floodlight, light reflection, so that the assembled lattice screen, each pixel display contrast will be high. Secondly, it can avoid the reflection of external light and improve the display effect of the screen, especially for outdoor applications.

Black PCB more advanced?

The difference between black PCB and other color PCB, such as blue PCB and yellow PCB, is that the color of solder resist paint on the final brush is different. If the PCB design and manufacturing process are exactly the same, the color will not have any impact on the performance.

Black PCB surface circuit wiring is difficult to identify, almost all covered, so this will increase the difficulty of later maintenance, and in the manufacturing process, black PCB hole alignment is the most difficult, is a kind of inconvenient color, so black price will be higher. The reason why "color represents high-end or low-end" is that manufacturers like to use black PCB to make high-end products, and red, blue, green, yellow and others to make low-end products.

Rocket PCB is good at making all kinds of PCB colors, green, white, black, red, yellow, blue, matt green and matt black are available, and there is no additional cost of different ink.