To check the adhesion of the coating, a mesh incision test is performed (specifications: DIN EN ISO 2409 and ASTM D3369-02). After painting, the paint layer of the plastic part is cut into a grid shape. Next, apply standard tape to the cut mesh, secure the tape and then abruptly tear it back off. If there is paint on the tape, it indicates that the adhesion of the paint is not good. The mesh is cut to show the adhesive strength of the paint layer on the plastic part

Test ink

Measurement method for estimating surface energy: If the test ink accumulates in one place after being applied to the surface, the surface energy of the solid is lower than the surface energy of the ink, and if kept wet, the surface energy of the solid is equal to or greater than the surface energy of the liquid. By using a series of test inks with gradient surface energy, the total surface tension of a solid can be determined. However, this method cannot determine the polar and non-polar parts of the external energy.

Contact Angle/marginal Angle

The contact Angle refers to the Angle formed when the projection of a stationary liquid drop on a solid is observed, and the droplet is tangent to the solid surface at the three phase intersection. According to the physical definition, a contact Angle of less than 90° on the surface is hydrophilic (wettable), and a contact Angle greater than 90° is hydrophobic (non-wettable). With the plasma surface treatment, the contact Angle changes (becomes larger or smaller). By appropriate plasma process flow or by appropriate coating treatment in the plasma process flow,?? The hydrophilic surface will change to a hydrophobic surface (with a hydrophilic coating treatment, the opposite effect is obtained).