Briefly describe the formation of plastic gravure printing line

The generation of knife lines is inextricably linked to the finish of the plate roller and the quality of the coating. Plates are divided into two types: hand-engraved plates and electro-engraved plates. The hand-engraved intaglio plates are not smooth, and the knife lines are easy to appear. The surface of the electric carving and intaglio plates is smooth, and the probability of producing knife lines is much lower than that of hand-carved plates.

When printing with hand-engraved gravure, the first time before the machine is used to sand the surface with 1000 # water-resistant sandpaper, the specific approach is: the printing speed faster, empty machine operation, grinding sandpaper back and forth, but can not be used over Big, otherwise it will damage the cell. After polishing, the drum is wiped with a soft cloth and then printed on the machine. The knife line phenomenon is reduced a lot. It should be noted that this work needs to be performed by experienced personnel. If such a knife line appears during printing, the method is as before.

The hardness of the coating is also related to the production of the knife line. The hardness of the coating is not enough. It is easy to damage under the action of the doctor blade, and it will also generate the knife line. Sometimes this knife line is not available, also called the “hidden knife line”, often appears in the printless pattern. This knife line is only easy to find under the reverse side of the fluorescent lamp. There are two solutions to this knife line. First, after this happens, use a 1000# water-resistant sandpaper to gently grind the coating. It will be better, but often after printing for a period of time, it will appear again. Therefore, it is better to carry out the deplating treatment. In severe cases, it is necessary to re-plate; the second is to adjust the squeegee, increase the pressure of the squeegee, and to the layout Hair dryer also received good results.

Cut line and work environment

The production of knife lines has a lot to do with the environment. If there is dust in the operating environment, dust can enter the ink and cause knife lines. The workshop should first isolate the printing unit to reduce the flow of personnel. The room is equipped with air-conditioning facilities and dust removal equipment. At work, the first color sequence and second-color inks are filtered and printed on the machine before work. There are special health workers to clean the house during work hours. The environment must be kept clean.

The production of knife lines is various and the format is not specific. This requires the operator to develop habits of summing up experience and actively cooperate with the factory management to minimize knife line failures.