PCB solder masking has become an integral part of today's printed circuit board technology. It is difficult to find any printed circuit board without a solder mask, although there may be some privately developed printed circuit boards without solder mask. Even if the number of printed circuit board orders is very small, there is solder resist for prototyping. The use of solder masks on commercially manufactured PCBs is now a global standard.

Why use PCB solder mask?

As is apparent from the name, the use of solder resist on the PCB prevents solder from adhering to specific areas of the PCB surface. Only the specified area of ​​the component is connected to receive the solder, while the rest of the PCB  is covered with a solder mask. This ensures that only the desired area will be soldered. The main advantage of solder resists is that solder is only applied to specified areas, which prevents solder from entering the rest of the circuit, reducing the likelihood of solder bridges that can cause short circuits.

Modern printed circuit boards have very thin and closely spaced tracks and component leads that can cause short circuits after the soldering process. This problem can be prevented by using a PCB solder resist. Solder resists not only prevent shorts and small bridges, but also treat them as additional PCB layers. The solder mask acts as a PCB insulation layer to prevent corrosion, oxidation or damage caused by chemical exposure.

Since these problems can damage the PCB for a long period of time, the solder resist can be considered to improve the reliability of the PCB.