The commonly used plastic film are: PE, PP, PVC, PS, PVA, PC, PET, CA, NY, these plastic film printing features are:
1. The plastic film is a non-polar polymer compound, the printing ink adhesion is very poor, in order to make the plastic film surface has good printing ink adhesion ability, enhance the printing quality of soundness is before printing surface activation treatment;
2. Hygroscopic most affected by the surrounding air relative humidity and expansion deformation, leading to poor overprint;
3. Affected by the change of the tension of film in the printing process, allow in strength, elongation increased along with the increase of tension, bring difficulties to the accuracy of the color printing overprint;
4. The surface is smooth, without wool stoma, printing ink layer is not easy to sessile or fixation is not strong, after the first color printing, easy to color overprint ink stick out, make pattern and text is incomplete, cause defects;
5. The surface of the reservoir seepage.Thin film made of mixed with additives, additives in the process of printing parts easy to seep, in the film surface to form a layer of oil layer, printing ink, paint, or other adhesive is not easy in this kind of thin film surface bonded firmly;
6. Because of the plastic film is a non-polar materials, there is no wool stoma, ink is not easy to dry, these characteristics are not conducive to printing, so must be carried out on the plastic film surface treatment before printing.