The quick-frozen frozen food packaging bags on the market can be divided into single-layer packaging bags, composite packaging bags, and multi-layer co-extrusion packaging bags. Among them, single-layer quick-frozen frozen food packaging bags, that is, pure PE bags, have poor barrier effects and are mostly used for fruit and vegetable packaging;
Composite soft plastics are relatively good in terms of moisture resistance, cold resistance, and puncture resistance;
In the production of multi-layer co-extruded frozen food packaging bags, PA, PE, PP, PET, EVOH and other raw materials with different functions are melt-extruded, and finally made by inflation molding and cooling composite, which has no pollution in packaging performance , High barrier, high strength, high and low temperature resistance and other excellent characteristics.
Quick-frozen frozen food packaging bags integrate various factors. Among the three types of quick-frozen frozen food packaging bags, composite soft plastics are widely used. Such frozen food packaging bags also have many combinations in the material structure of quick-frozen frozen food packaging bags:
One is PET/PE. This material structure is more common in the packaging of quick-frozen food products, and has good moisture resistance, cold resistance, and low temperature heat sealing performance, and the production cost is relatively low;
Second, BOPP/PE and BOPP/CPP. The frozen food packaging bags of these two structures have excellent moisture resistance, excellent cold resistance, high tensile strength for low-temperature heat sealing, and good economy. It is worth mentioning that BOPP/PE has a better feel than PET/PE, which is good for product marketing;
Third, PET/VMPET/CPE, BOPP/VMPET/CPE. The three-layer structure of the packaging bag is stronger and more stable than single-layer and double-layer, and has high barrier performance. In addition, the presence of the aluminum-plated layer also has a more prominent advantage in printing performance. However, compared with the above materials, low temperature heat The sealing performance is slightly worse and the cost is higher;
Fourth, PA/PE, PET/PA/LLDPE, PET/PA/AL/PE, PA/PE. These four types of material structures are more resistant to freezing and impact resistance, and the PA layer ensures good puncture resistance. The disadvantage is that the production cost is higher, and they are generally used for angular or heavier food product packaging.