Analysis of Problems and Solutions of Coating Roller Rubber

　　During the printing process of self-adhesive labels, printing failures occur from time to time due to the relatively complex structure of the printing machine, as well as various factors such as materials, processes, environment, and the skill level of personnel. A failure may be caused by multiple reasons, and a single reason may lead to multiple failures, making troubleshooting quite difficult. Although there are some failures that cannot be resolved at present, most can be eliminated, and the methods for elimination are not complicated. The key is to find the correct method to identify the cause in a short time and minimize downtime. Based on practical production experience, the following summarizes the issues and solutions.Laminating roller glueProblems and solutions encountered.

　　Laminating roller glue is one of the common post-processing technologies for paper printed products, which involves bonding a plastic film coated with adhesive to paper printed products under heat and pressure. The surface of the printed product has a thin and transparent plastic film, making the surface smoother and shinier, which not only enhances the gloss and durability of the printed product but also extends its lifespan. At the same time, the plastic film provides protection against water, dirt, wear, folding, and chemical corrosion. During the laminating process, various quality issues often arise, directly affecting the quality of the lamination of the printed products, leading to unnecessary losses and waste.

　　Laminating roller glueSurface defects, low hardness, insufficient pressure of the laminating roller, and misalignment between the laminating roller and the bottom roller, etc. Additionally, if the ink layer is too thick, or if the ink layer has not completely dried during coating, or if the machine speed is too fast, it can also lead to such failures. Under normal circumstances, the pressure of the laminating roller can be increased; the parallelism between the two rollers can be adjusted; the machine speed can be reduced or the ink composition can be changed to resolve the failure. Furthermore, if there is a problem with the laminating roller itself, it needs to be replaced with a new laminating roller glue.

　　During the production process of laminating roller glue, the main reasons for the wrinkling of the surface of label printed products are: 1. The paper printed products are damp, or the temperature and humidity of the production site are high, which can easily cause the paper of the label printed products to tighten or form wavy edges. 2. Uneven roller pressure or uneven gaps between guide rollers can lead to unevenness and wrinkling of paper products during the laminating process. 3. When the conveyor belt transports the paper, the printed paper is skewed, either regularly or irregularly. 4. The composite film is too loose or the tension of the base paper is too high, resulting in inconsistent tension on both sides of the composite film.

　　In the production process, once wrinkles are found on the surface of the laminating roller glue label printed products, the following methods can be tried to solve the problem: 1. Strictly control the temperature and humidity changes in the workshop, flatten the deformed printed paper, and then proceed with the laminating operation. 2. Adjust the laminating pressure between the glue roller and the heating roller and the gap between the guide rollers. 3. Adjust the conveyor belt and side guide of the guide roller, paying attention to the moment of feeding paper. 4. Stretch the composite film, reduce the tension of the base paper, and switch to a suitable composite film.

　　In summary, there are many reasons that affect the quality of label products. To achieve the desired effect after coating or laminating labels, it is essential to strictly follow the process and standard operations, analyze the reasons in a timely manner to identify problems, and then resolve them promptly. Only in this way can waste be reduced, and the quality of label products continuously improved to meet the needs of market customers.