Classification of composite substrates for plastic packaging bags

With the development of science and technology, the flexible packaging industry has adopted a large number of new technologies, new processes, new equipment and new materials, making the flexible packaging composite substrate more and more types and better performance. Classified by material, it mainly includes paper substrate, plastic film substrate, metal foil substrate and evaporated oxide film substrate; The common materials of paper substrate include kraft paper, cellophane, wax paper, wrapping paper, PE, PP, pet, PA, aluminum foil and vacuum aluminized film. According to the processing method, it mainly includes vacuum coating substrate, extrusion blown substrate, cast film substrate, biaxial tensile film substrate, etc. Common materials include aluminum coating and SiO2 coating. PE, PP, pvc, eval, etc., cpp and cpa are classified into vacuum aluminized film substrate, extrusion blown substrate, tape cast film substrate, tensile film substrate, etc. according to their functions. Common materials include vacuum aluminum coating, SiO2 coating, BOPP, BOPET, BOPA, OPP, OPA and other heat sealing base materials. Because they are directly in contact with the contents of the package, they must meet the following requirements: five poisons, tasteless, colorless. 2. Chemical stability. When contacting with the packed contents, it will not be eroded and penetrated by the contents, and has good physical property of resistance to the contents. 3. High heat sealing strength, good low-temperature heat sealing performance. 4. Good machinability, suitable for clear and assembly line filling.