Selection requirements for laminating materials of automatic laminating machine:
       The plastic films commonly used in the current laminating process of automatic laminating machines are: polyvinyl chloride (PVC), polypropylene (BOPP) and polyester (PET) films. Among them, BOPP film (15～20pm) is flexible, non-toxic, high in transparency, and cheap in price. It is an ideal composite material in the laminating process of the automatic laminator.
        In order to meet the requirements for the use of laminating printed matter of the automatic laminating machine, the plastic film should meet the following requirements:
        (1) Thickness directly affects the light transmittance, refractive index, film fastness and mechanical strength of the film, and the appropriate film should be selected according to the performance of the film itself and the purpose of use;
       (2) After being treated by corona or other methods, it has better wetting performance and adhesion performance;
      (3) The higher the transparency of the film, the better, so as to ensure the best clarity of the printed matter covered;
        (4) The film should have good light resistance, not easy to change color under long-term light exposure, and have certain mechanical strength and flexibility characteristics;

       (5) The appearance of the film surface should be smooth, free of irregularities and wrinkles, no defects such as bubbles, shrinkage holes, pinholes and pits, and no contamination of the film surface with dust, impurities and grease.