Good printing quality is the foundation to produce high quality packaging products. In packaging printing industry, there are 8 quality issues that need attention in printing.
First, network blocked problem
Printing dot clogging is more common, and the dot jam has a certain relationship with the printing plate. When making a printing plate, the number of lines of the anilox roller and the printing plate are not matched, and if it is made too high, the plate printing phenomenon will occur. Generally, the ratio of the anilox roller to the printing plate is 1:4.5, that is to say, the anilox roller is 250 mesh, and if the mesh wire is 65 wire, the dot printing clogging phenomenon occurs.
Second, leaving white edge problem
The hardness of the printing plate is higher than 45 degrees, and it is very easy to appear printed white when printing large color blocks. Since the hardness of the printing plate is too high, the ink transferability of the printing plate is lowered, that is, the amount of ink used is directly reduced, resulting in the paper not being able to obtain a sufficient ink coating layer, causing the printing white phenomenon.
Third, printing color registration accuracy problem
In the production process, the scale of the printing is not correct or the bleeding of the printing plate is different, and the color registration is not accurate. The scaling of the printing plate is calculated according to the circumference of the printing machine cylinder. If the calculation is wrong, the size of the pattern will change and the color will be inaccurate.
Fourth, printing not clear problem
The unclear printing is mainly reflected in whether the printed patterns are printed or not, and some have already been printed. This is mainly because the flatness of the printing plate is poor and the phenomenon of high and low is high during the plate making process. This situation is very common. . Generally, in this case, only the back side of the printing plate is padded with tape to make the printing surface flat.
Five, printing double problem
The printing ghost caused by the printing plate is mainly that the edge of the printing plate is not smoothed during the printing process, which causes the printing quality problem caused by the outward pressing of the printing plate, and the printing burr phenomenon also occurs, and the printing can only be completely re-printed. Version.
Sixth, printing error problem
In the process of paperboard, the content of the printed pattern is wrong, and the common ones are text errors and less printed patterns. The solution to this type of method can only improve the carton inspection capability of the printer personnel.
Seven, the printing position is not correct problem
The incorrect position of the printing plate is mainly caused by human factors. During the printing process, the layout position is not placed at the specified position, resulting in incorrect printing position. Solving such problems requires the printer to carefully check the printed manuscript.
Eight, printed text paste
There is a similarity between the printed text paste and the unclearness, but the most common cause here is the problem of the plate making process. Especially when the text is relatively small, the printing plate is too shallow in the washing process, and the ink will accumulate when the printing starts. At the edge of the print, it is easy to block the printing plate, resulting in a printed text paste. Once such problems arise, they can only be resolved by re-creating the printed version.