Classification and use of packaging film
The packaging film is mainly compounded and extruded from several different brands of polyolefin resins. It has high strength, puncture resistance, and high performance. It is more stable, stronger, and waterproof for the packaging of goods stacked on pallets. It is widely used in Foreign trade exports, paper, plastics, metals, chemicals, building materials, food, and pharmaceutical industries. What types of packaging films are described below.
Polyvinyl alcohol coating high barrier film
The barrier performance is not only better than the five-layer co-extrusion benefit package, but the packaging cost is also greatly reduced.
Biaxially oriented polypropylene film
Biaxially oriented polypropylene film is co-extruded, biaxially stretched, and prepared by polypropylene particles. Due to the orientation of the stretched molecules, the film has high physical stability, high mechanical strength, good air-tightness, high transparency, gloss, toughness, and wear resistance. It is currently the most widely used printing film, generally, 20 ~ μ thickness 40 meters, The most widely used is 20μm biaxially oriented polypropylene film. The main disadvantage is poor heat-sealing performance, so it is generally used as the outer film of composite films, such as polyethylene film, which is ideal for moisture resistance, strength, rigidity, and transparency. Yes, suitable for dry foods. As a result, the biaxially oriented polypropylene film has a high surface polarity, high crystallinity, and low surface free energy. Therefore, the performance of printing inks and adhesives is poor, and the adhesion is poor. Surface treatment is required before printing and lamination.
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