Background technology of paper plastic packaging bags

Paper plastic bags are made of a composite of plastic and kraft paper. The plastic layer is usually made of flat silk woven fabric with polypropylene as the base material, while the kraft paper is made of refined composite special kraft paper. The two are bonded by melting plastic heat laminating film. It is easy to transport and load granular materials, with high strength and good waterproof performance, making it a popular and practical ordinary packaging material at present. With the advancement of technology, the process of using extrusion molding technology to obtain paper plastic composite films and coating them on kraft paper substrates by heating, thereby forming a plastic layer on the surface of kraft paper to produce paper plastic packaging bags, has been applied. In recent years, paper plastic packaging bags have gradually expanded their application fields, and have been promoted in various fields such as food packaging, medical and health care, and cosmetics. However, the paper plastic packaging bags produced by current process technology have poor air barrier performance. When used in food packaging, they are prone to oxidation, moisture and deterioration. When used in medical and cosmetic product packaging, they are prone to chemical agents being released outward through the packaging bags.