Side sealing packaging bags are made of plastic material with barrier, heat tolerance and sealing. Can prevent food spoilage, prevent the oxidation of vitamins in food. Generally choose multi-layer plastic composite, common including PET/AL/PE, PET/NY/PE, PET/MPET/PE, PET/AL/PET/ NY/AL/PE, PET/NY/AL/RCPP, high temperature dry distillation bag wet food, etc. Plastic composite co-extrusion film, will compound aluminum foil, because aluminum foil packaging bag it has good barrier. Block air, block sunlight, block oil, block water, almost all substances can not penetrate; Aluminum foil bag has good air tightness; Aluminum foil packaging has outstanding shading, but also has a good oil resistance and softness. It looks high grade and prominent, with good sealing effect. The bag mouth can be simply sealed, easy to reuse and can make the product inside not easily affected by moisture.