The role of circuit board three anti-paint and precautions

2019-10-23 18:42:43 Juding Circuit Technology

Three-coating is a specially formulated coating used to protect circuit boards and their associated equipment from the environment. The three anti-paint has good resistance to high and low temperature; it forms a transparent protective film after curing, and has superior properties of insulation, moisture, leakage, shock, dust, corrosion, aging and corona resistance.

The role of circuit board three anti-paint and precautions

Moisture is the most common and destructive factor for PCB boards. Excessive moisture greatly reduces the insulation resistance between the conductors, accelerates high-speed decomposition, lowers the Q value, and corrodes the conductor. We often see that the metal part of the PCB circuit board is made of patina or is not coated with three anti-paint metal copper and steam, oxygen and its chemical reaction.

Applying three anti-paint to printed circuit boards and components can reduce or eliminate electronic operating performance degradation when it is likely to be affected by adverse operating conditions. If the coating can maintain its effect for a satisfactory period of time, such as greater than the life of the product, it can be considered as having reached its purpose of coating.

Operational notes:

    1. The PCB board must be cleaned with wash water, and alcohol should not be used.

    2. After the PCB board is fully cured, it can be painted with three anti-paints. The cleaned board can be baked in the oven.

    3. If it is sprayed with three anti-paints, shake the bottle before spraying, so that the paint inside can be evenly distributed, and then spray against the board.

    4. If it is brushed three anti-paint, brush the paint in the bucket and brush it evenly before brushing.

    5. All three anti-paints cure at room temperature for a few minutes to ten minutes, and full cure is 24 hours. It can be heated to 60 degrees and a half hours to fully cure.

Of course, with the continuous advancement of technology, PCB board manufacturing has been applied to PCB board manufacturing processes suitable for assembling tin-casting processes such as QFP and BGA with smaller pitches, but the practical application is relatively small. At present, some PCB board manufacturing adopts OSP process and immersion gold process to replace lead-free tin-spraying process. From the technical development, some factories adopt the process of sinking tin and sinking silver. With the trend of lead-free in recent years, spray The use of tin technology has also been further limited.