, according to the classification of the sticky materials of the protective film, it can be divided into adhesive protective film and self-adhesive protective film. Each has its own advantages and disadvantages. Self-adhesive protective film is mainly used for products with high appearance quality. This kind of protective film is usually co-extruded with two or more layers, one of which is made of self-adhesive material. It does not need to be coated with glue to stick itself. There are many kinds of self adhesive materials. Usually, electrostatic film is made of EVA or other modified materials. The principle of electrostatic self-adhesive is that the self-adhesive material belongs to high polymer, low crystallinity, there are many exposed molecular chains on the surface of the film, these molecular chains are easy to fill in the surface pores of the attached object, so that the two bond with each other.