Welcome to the Xianghuai Website.We are mainly engaged in designing and manufacturing flexographic printing machines.

The flexo printing machine has occupied a certain market in the high-end packaging printing field in China due to its post-linking processing, the combination of various printing methods, and the use of environmentally-friendly water-based inks, especially in the printing of beer labels and soft-packed cigarettes. China has a great advantage. However, compared with offset printing and gravure printing, flexo printing also has some shortcomings, such as large deformation of printing plates, which are manifested in the printing operation as inaccurate overprinting and paste. Here are some simple explanations for the problem of overprinting.

1. Tension control

   In the printing process, due to the unstable tension, it is easy to appear a large amount of waste, so the tension of the paper tape should be strictly controlled. Generally, there is a magnetic powder tension controller and a tension driving roller at the unwinding and winding of the machine, and both have tension display. Because the paper has a joint, the tension will always fluctuate each time the joint comes over, and the gauge can be pre-adjusted to reduce the amount of waste. If the printing job is to be replaced, if the newly replaced paper tape is wider, the tape will be worn by the narrower paper tape on the front, and the wide paper will be used to form the bridging effect in the middle of the rubber roller. The two sides of the belt are tight and the middle is loose, which has a great influence on the slitting unit at the back. At this time, it is necessary to replace the rubber roller or to smooth the surface of the old rubber roller and continue to use it. In addition, the gas riser shaft will become loose after a long time, and it is necessary to check it.

2. Guarantee plate accuracy and accurate alignment

   When installing the plate, it is generally hand-applied, which requires a high degree of proficiency. The edge of the plate must be parallel to the axis of the plate cylinder, and the seam should be as close as possible. Otherwise, it is easy to cause the plate at the seam. The roller beats. If a plate is replaced separately, the plate is often overprinted due to different plate making time. At this time, the plate can be softened by a hair dryer, and then stretched longitudinally or laterally to be consistent with other plates.

3. Constant speed printing

   For large-volume printing, under the conditions of mature technology, it is advisable to adopt constant speed printing, so that the influence of the drying device on paper deformation is relatively uniform and easy to overprint. Other process parameters such as ink viscosity, tension setting, etc. can all have a fixed range, so that the quality can be guaranteed.