If it can't be solved, wash it by sulfate, then it could be probably faded.
Generally speaking, the film is PE (polyethylene) film with single layer structure. It's transparent. Or it is two-layered with composite structure. One of the two layers is BOPP printing film. The other is PET film coated with aluminum. The two kinds of film mentioned above needs to be covered with a layer of PSA before it's used on profiles.If it's difficult to peel down from the profiles, it means the quality of the PSA is not good enough.
