I am using Upilex polymer film for Laser Micro machining, after machining the chips are used in the rotor for sample sparying. When I use these Upilex polymer film I get lot of dirts when the film is scratched by the rotors. But I can clean these dirts using Proponal , but the question is why these dirts turn up when they are rubbed by those rotors. I tried rubbing these polymer films using flat metals they too show dirts when they are rubbed. Please help me out .