There is a question about why PCB is almost green for the fans of learning circuit. In fact,it’s not always green for all PCBs, depending on the designer.
Actually, the reasons why we choose green is that green is good for eyes of manufacturer and repairman who work in PCB production line for a long time .In addition the usual colour is yellow,black and red.Each colour is painting spray in the surface after manufacturing.
Another reason is everyone is used to green,so the factory is ready for green painting is maximum and the oil cost is lower in relativity.What’s more,it’s easier for workers to distinguish white colour for different routing when repairing PCB , however,black and white is more difficult .Every factory distinguish superior and basis series with these colour for itself product grade.For example, the company HUASHUO who producing the computer mainboard, yellow is basis, black is superior .And blue board is superior and green is basis in YINGTAI.
Black PCB cost is higher than other colour at present,but it doesn’t mean black color PCBs’ electrical performance is better. In fact,it’s more difficult for black color PCB hole,so the yield is lower than PCB other colour in relativity.