What is the structure and performance of protective film?

At present, the protective films on the market can be roughly divided into double-sided protective films and three structures: base protective film and coating protective film.
(1) General process: Apply rubber evenly on the base material, base material rubber particles and base material mixed layer.
(2) Co-extrusion process: Mix rubber particles with the base material. There is no glue on the surface, but there is a certain stickiness and no residual glue.