The production process of PVC is not complicated. The common production line is generally composed of rolling press, printing press, back coating machine and cutting machine. It mainly produces thin films with thickness of only 0.3 mm to 0.7 mm by direct stirring of rolling press, roller rotation and high temperature rolling. At the same time, the film is printed on the front of the film by printing machine, and a layer of back coating is attached on the back of the film by back coating machine. 。 Don't underestimate this layer of back coating, it is an important guarantee for the high quality performance of PVC film. Back coating is a kind of high-energy affinity agent, which is composed of special materials. It is precisely because of this layer of back coating that PVC film can be tightly integrated with medium-density board or other plates. It has not been glued for ten or even fifteen years.