Why do I need to do corona treatment? The purpose of the corona treatment is to change the surface energy of the protective film, making it easy to bond with printing inks, coating materials and adhesives.
For example, the PE film undergoes structural changes after production. Within a few days, the polymer changes from amorphous to crystalline, affecting the effect of corona treatment. After the corona treatment, the cross-linked structure of the plastic surface layer is less than the cross-linked structure of the inner layer, so the functional groups of the surface layer have higher mobility. Therefore, in storage, many plastics appear corrosive effect of the corona treatment, and the migration of additives from the interior to the surface is also a factor that causes the surface energy to drop and affect the adhesion. This negative effect cannot be completely suppressed.