PET/PVDC/PE composite film is add high obstract material PVDC between PET and PE. In practical application process, put liquid in PET/PE compound film, if there is any liquid which has strong volatility, after a period of time stored, the liquid will volatilize, the quantity will reduce and the face of the product will inward depression. It will reduce the effective protection capablity of the inside foods. Seriously, it will cause the disput with consumers. Then the economy and the image of the company will be damaged. Due to the good obstruct ability of PVDC, it plays a good anti-infiltrate effect to the product in packing, it's the ideal packing material for easy humidity absorb foods. PVDC material itself is the latex character, has quite big brittleness after the solidification. In the coating process and post-processing, the pivotal technical is to reduce its brittleness, make it normally used in the room temperature environment. Before, the technical ability is too poor to do so. That is one of the technical difficulties of PVDC compound material. However, the three compound processing technology is more difficult. At present, only few companies which has independent research and development ability can do it in China. My company starts from 1980s, after a few years research and testing, finally succeeded in produce the PET/PVDC/PE costed film which is truly apply to the liquid packaging. It mainly takes PET film as the basal material, then coated PVDC(import from BASF in Germany) and PE . During the production processing, the temperature, coated quantity and times and other important considerations are checked strictly to make the final product meet the foreign products quality standards. The obstruct ability is 5 times higher than the common PET/PE. Meantime it has a certain rigidity, flexible and can be widely used in packaging various easy volatile liquids. The period for protection can really reach the required standard.