Poor adhesion of the coating to the surface of the non- […]
Poor adhesion of the coating to the surface of the non-absorbent substrate
The substrate is a non-absorbent or non-porous substrate (such as PVC or PET film), and the adhesion of the varnish coating to the surface of the substrate may be poor. Solution: Prepare a scotch tape and a mesh tool, draw a cross line on the coating, and then tape it. The size of the coating tape torn off by the tape represents the degree of cure and adhesion of the coating. If the coating is not torn off, the adhesion is good. If the coating is torn off over a large area, this varnish is not suitable for use on non-porous substrates and should be replaced.