The circuit board can be called a printed circuit board or a printed circuit board. The English name is (PrintedCircuitBoard)PCB, (FlexiblePrintedCircuitboard)FPC circuit board (FPC circuit board is also called flexible circuit board. Flexible circuit board is based on polyimide or polyester film A substrate made of a highly reliable and flexible printed circuit board. It has the characteristics of high wiring density, light weight, thin thickness and good bendability), soft and hard combination board (reechas, Softandhardcombina TIonplate) )-The birth and development of FPC and PCB gave birth to a new product of soft and hard board.
Therefore, the rigid-flex board is the flexible circuit board and the rigid circuit board, which are combined together according to relevant process requirements through pressing and other processes to form a circuit board with FPC characteristics and PCB characteristics.
Why the circuit board is green
The green part is called solder mask. The ingredients are resin and pigment. The green part is green pigment. There are also various other colors, which are no different from decoration paint. The assembly solder is paste-like and flowable before it is printed on the circuit board. After it is printed on the circuit board, it is finally “cured” so that the resin is cured and hardened by heat. The purpose of solder mask is to protect the circuit board from moisture, oxidation and dust. The places that are not covered by the solder mask are usually referred to as pads, and solder paste is used.
Generally speaking, the entire electronic board-level products have to go through the process of plate making and post filming. In the process of plate making, there are several processes that go through the yellow light room. The visual effect of green in the yellow light room is better, but this is not Main.
The common ones are red, yellow, green, blue and black. Due to process problems, many line inspections still rely on workers to see with their eyes (of course, most of them now use flying probe tests). Keeping the signs with bright eyes, this is a Very tiring work, green is relatively the least harmful to the PCB circuit board processing.
Blue and black are because they are doped with cobalt and carbon respectively, which have certain conductivity, so there is a risk of short circuit. Green PCB is more environmentally friendly and will not release toxic gases when used in high temperature environments. PCB circuit board processing.
There is another reason, because the commonly used color is green, so the factory spares a lot of green paint, so the cost of oil is relatively low. And because when repairing the PCB board, different wiring is easier to distinguish the difference from white, and black and white are relatively difficult to see. In order to distinguish its own product grade, each factory uses two colors to distinguish high-end series and low-end series.