The most commonly used solder mask is the green ink, so it is called the green oil bridge and also called the solder mask bridge and the solder mask dam. Solder-resistant ink is a "separation tape" made to prevent short-circuiting of SMD component pins in the batch production of the factory. To control the green oil bridge of the FPC soft board, it needs to be controlled during the solder mask process.

What is the function of FPC solder mask?

FPC solder mask ink is used instead of the original cover film, and its function is the same as the cover film.

The main functions are as follows:

1. The FPC flexible board ink is printed on the copper foil circuit on the surface of the circuit board to isolate the contact between the copper foil and the outside world and play a role in surface insulation.

2. After the circuit board is produced, it has to go through multiple processes. In order to prevent the copper foil circuit from being damaged during the transportation and production, a protective layer should be printed to protect the circuit and prevent the circuit from scratches.

3. After the circuit board solder resist ink is completely cured, it can prevent conductive foreign matter from falling into the circuit and causing a short circuit.

4. FPC circuit board solder resist ink has the functions of anti-electroplating, chemical tin and gold resistance. SMT can also play a good role in solder protection.

Therefore, in general, the FPC soft board solder resist ink can be regarded as a layer of protective paint, which plays a protective role to a large extent.