The decorative printing of plastic bottles is mainly screen printing and flexographic label printing. Screen printing belongs to direct printing, while self-adhesive trademark printing is indirect printing, in which images and texts are printed on the self-adhesive label printing machine and then transferred to plastic bottles. Although both of them have their own advantages and complement each other, self-adhesive trademark printing. It is more independent than screen printing, so it is the investment direction of small and medium-sized enterprises.

Small and medium-sized self-adhesive printing enterprises can't bear the huge investment of unit flexographic printing machines, so most of them adopt flat or circular self-adhesive trademark printing machines with relatively compact structure and low price. This kind of printing machine is mostly modified from relief printing machine, and its ink supply mechanism and printing impression mechanism are more complicated than the unit flexographic printing machine, and it is also very troublesome to operate. In order to ensure high quality, the technical level of operators is very important. The common problems and solutions in the printing process are briefly analyzed and discussed for the reference of peers. Self-adhesive label printing generally needs to be cut into a certain shape before it can be used. On the printing press with one-time die cutting, the synchronization of die cutting and printing is very important. The up-and-down movement of the die cutting and the up-and-down movement of the printing table are driven by the main transmission shaft, so there is synchronization. However, the cutting position is determined by the double crank structure to control the rotation distance of the traction roller, so it is very important to adjust the crank radius and the pressure of the platen.