The defects in figures 1 and 2 could be the result of poor cleaning process design or incompatibility of the surfaces being coated. In the first case, it's questionable if the dewetting would have any impact on reliability, but it's better to solve the problem on future products. Figure 1 shows conformal coating has separated from the surface of a plastic QFN/LGA body, which is not uncommon on many plastic parts. Devices often have release agents on the surface, which make coating adhesion difficult to maintain. A separation may not normally be reworked. In this case the root cause should be established, as all the coating has completely lifted.
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