The quality standards for pre-coated films primarily focus on regulating the physical, chemical, and appearance properties of the film layer. Physical properties include film thickness, adhesion, flexibility, and impact resistance. Film thickness must be uniform and meet design requirements. Adhesion is assessed using the cross-cut test or pull-out test to ensure the film layer does not peel during processing and use. Flexibility and impact resistance are tested through bending, folding, or drop ball tests to ensure the stability of the coating during transportation, processing, and use.
Chemical properties and appearance quality are also important components of the quality standards. Chemical properties mainly test corrosion resistance, weather resistance, and chemical resistance, for example, by evaluating the protective effect and durability of the coating through salt spray tests, acid and alkali immersion tests, or ultraviolet aging tests. Appearance quality includes gloss, smoothness, color consistency, and the absence of defects such as bubbles, cracks, and peeling. By adhering to these quality standards, pre-coated films not only ensure their protective performance and durability,
