Composite packaging is a combination of two or more materials through one or more dry composite processes to form a composite packaging with certain functions. Generally, it can be divided into base layer, functional layer and heat sealing layer. The base layer mainly plays the role of beauty, printing and moisture resistance. Such as BOPP, BOPET, BOPA, MT, KOP, KPET, etc.;
The functional layer mainly plays the role of barrier and light-proof, such as VMPET, AL, EVOH, PVDC, etc.; the heat-sealing layer is in direct contact with the packaged items, which is adaptable and resistant to penetration good heat sealing, as well as transparency, openness and other functions, such as LDPE, LLDPE, MLLDPE, CPP, VMCPP, EVA, EAA, E-MAA, EMA, EBA, etc.
The composite flexible packaging material can finally be used in various packaging bags. There are two ways to make bags. One is that the packaging manufacturer uses roll film to fill on the automatic packaging machine, and then forms and packs them into various packaging bags; the other is that the bag-making machine forms various packaging bags and then fills the contents. . Due to the precise control of professional bag making, the beautiful bag shape, the large changes in bag making, and the many bag shapes, in many cases, bags are made first. The main varieties of bags are: three-side sealing bag (hand-sealed bag), back-sealed bag, folding help (organ bag), stand-up bag, etc.