Many customers believe that after a hole is broken, the film temperature and pressure should be increased to enhance its adhesion. However, this view is not correct because the solvent in the corrosion resistant layer evaporates excessively when the temperature and pressure are too high, making the dry film brittle and thin. During development, it is very easy to break the hole. We always need to maintain the toughness of the dry film. Therefore, after a hole is broken, we can improve it from the following points:

　　1. Reduce film temperature and pressure

　　2. Improve drilling edge

　　3. Increase exposure energy

　　4. Reduce development pressure

　　5. After applying the film, the parking time should not be too long to avoid causing the semi fluid like drug film at the corner to diffuse and thin under pressure

　　6. During the film application process, do not tension the dry film too tightly

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