The cast polypropylene film is a polypropylene film produced by a casting process, and can be divided into two types: ordinary CPP and cooking grade CPP. The transparency is excellent, the thickness is uniform, and the longitudinal and lateral properties are uniform, and generally used as a composite film. Layer material. The thickness of ordinary CPP film is generally between 25~50μm. After compounding with OPP, the transparency is better, the surface is bright, and the hand feel is firm. The general gift packaging bag uses this material. This film also has good heat sealability. The thickness of the cooking grade CPP film is generally between 60 and 80 μ m. It can withstand high temperature cooking at 121 ° C for 30 min. It has good oil resistance and air tightness and high heat sealing strength. The inner layer of general meat packaging is uniform. A cooking grade CPP film is used.