According to the different film-forming processes, PE plastic films can be divided into blown film (IPE), drooling film (CPE) and low foaming film. The tensile strength and aperture of IPE film are better than that of CPE film, and front printing can be used as food bag and clothing bag. The thickness of CPE film is uniform, and the ratio of surface gloss, transparency and heat sealability is good. PE can be printed on both sides, but the production cost is high. CPE film is mainly used as the inner layer of composite bags and the packaging of cosmetics, pickles and cakes. The low foaming film has good decoration, thick texture and is not easy to stretch and deform. It is printed on the front and used as New Year pictures, trademarks and handbags.