Most cartons manufacturers have a printing die-cutting and slotting machine that integrates printing, slitting, and indentation production functions. The equipment is simple and convenient to operate, the degree of automation is relatively high, the quality is easy to control, and it plays a certain role in the carton production process. The role, but if the equipment is aging, improper use of the machine, printing is prone to some failure phenomenon, now will be encountered in the production process of common printing problem class analysis.
Dirty, stenciled or partially illlustrated quality issues in layout graphics
Quality defects caused by bad parts associated with machine stamping
When the plate cylinder head, the platen roller head, the drive shaft, the gear, and the important parts associated with the embossing are worn and loose, the plate roller or the embossing roller may be beaten during the embossing process. Sliding phenomenon, due to the pressure instability, resulting in improper contact between the printing plate surface and the cardboard, resulting in the cardboard printing surface appears paste plate or local graphic image unclear. Through careful observation and analysis, the exact location of the fault was identified, and appropriate measures were taken to deal with it. The worn and loose parts were repaired to eliminate the fault phenomenon.
Quality failure due to poor ink roller
When the ink roller head is loosened and the roller roller body is bent, deformed or the surface is damaged, it will cause the layout to be dirty, the paste plate, or the local graphic is not clear. Should find out the reasons, take appropriate measures to deal with, so that the ink roller and the printing plate to maintain uniform and appropriate contact conditions, replace the damaged ink roller, in order to eliminate the phenomenon of failure.
Quality failure due to improper pressure roller adjustment
If the position of the pressure roller is too high or too low, so that the contact with the corrugated cardboard is too tight or too loose, there will be dirty prints, stencils, or local image imprints. Adjust the pressure roller to a suitable position so that the pressure The gap between the roller and the roller is adapted to the thickness of the board to ensure the position of the printed board and to avoid the occurrence of this malfunction.
Quality failure due to improper color sequence
If the layout of the fuller layout is printed in the first color group, when the corrugated cardboard enters the printing process of the next color group, since the printing image of the first color group of the cardboard has a large amount of ink and the drying speed is slow, it is extremely easy. Transfer the blots to make the layout dirty. In order to prevent this problem from occurring, it is advisable to arrange small-size layouts in the first color group, and to arrange large-size layouts in the subsequent color group to avoid imprint migration caused by dirty printing.
Quality failure due to uneven plate thickness
When the thickness of the rubber plate is not uniform, the height of the plate layout will be different. Wherever the layout is high, it is easy to paste, and where the layout is low, it is prone to ink incomplete, resulting in unclear imprinting. To avoid this unfavorable situation, the plate can be made into small pieces by means of sporadic plate making. Refers to the kind of plate-making process that saves the rubber plate and the plate-making core. It should be made of the same plate material, so that its thickness difference is relatively small. If the already prepared rubber plate has a poor thickness, it can be compensated by a multi-adhesive layer on the back of the partially thin plate, so that the entire plate can maintain a substantially uniform thickness, ensuring the printing pressure and the evenness of the printing surface of the plate.
Quality failure caused by non-uniform thickness of corrugated board
If the surface of the formed corrugated cardboard has a sabotage mark on the surface, the paper surface of the recessed area will also have unclear quality defects. If this is used to increase the printing pressure and make up for it, the text and the line layout will easily appear lumpy. Quality issues. In order to prevent the layout from becoming lumpy, corrugated cardboard should be handled lightly, lightly, and lightly (to control the stacking height) during stacking and handling, and should not be transported by poor production practices such as throwing, squeezing, and pressing.
Inaccurate or unstable quality problems in layout printing
Corrugated board warped printing position is not allowed
If the corrugated cardboard has a curling defect, slipping occurs easily during the positioning and feeding of the paper board, and even the rules on the machine do not touch the paper edge, causing the printing position of the paper board to be inaccurate or unstable. When the warped corrugated cardboard is printed, the relatively flat paper edge is used as the regular paper edge positioned when feeding. The most important is the control of the source of quality. Through the reasonable control of the single-sided machine operation process, the speed and preheating temperature of the machine, the moisture content of the base paper and the preheating area are in a relatively coordinated state; when comparing the paper, attention is paid to comparing the moisture content. Closed boxboard paper and corrugated paper are used for supporting the synthetic type, so that the corrugated paperboard produced has a relatively flatness and can effectively ensure the accurate printing position.
Inaccurate printing process caused by improper operation process
If the position of the plate is improper, it can easily cause the position of the platen to be inaccurate. Because corrugated paperboards with warp defects have just entered the plate rollers, if there is a slight amount of slipping, the tip of the paperboard will show a significant deflection. Therefore, the corrugated paperboard has a colored layout, and it should start as far as possible toward the rollers. The location of the paper is positioned, and the corresponding measures are determined to be repaired accordingly. After the loosening of the parts is eliminated, the printing position of the corrugated cardboard can be ensured accurately.
Inaccurate positioning due to bad machine
When the machine's chain, rules and Other parts have loose phenomenon, it is also easy to cause layout printing position is not accurate, this should take appropriate measures to repair, eliminate the loose parts phenomenon, in order to ensure the accuracy of corrugated board printing position.
Some of the above-mentioned quality problems that often occur in printing are caused by bad equipment and some are caused by improper operation. Therefore, we must always do a good job of maintaining the equipment and strictly require correct operating procedures to be effective. Prevent or reduce the occurrence of poor quality problems, so that the production efficiency and product quality can be improved synchronously.
---Carton Technology