Sometimes, the circular die-cutting of self-adhesive materials may result in uneven cutting marks and insufficient die-cutting depth. Due to the incomplete cutting of the surface material by the die-cutting knife, the waste edge may take away the label surface material during the pulling process.
When encountering this situation, the following solutions can be tried: first, check whether the pressure on the die cutting blade is uniform, and adjust the pressure applied by the die cutting seat on the die cutting blade; The second is to ensure that the die-cutting knife cuts through the label surface material. For new die-cutting knives, if a large amount of pressure is required to cut the material during initial use, it indicates that the height of the die-cutting knife does not match the material parameters, or the height of the die-cutting knife has a large tolerance with the target height during production.
The waste edge in the paper direction serves as the main force for waste removal. If its width is smaller than the axial waste edge width, it is easy to cause the waste edge to break during the production process.
It is recommended to ensure that the width of the waste discharge edge in the paper feeding direction is greater than or equal to the width of the axial waste discharge edge before production. Secondly, in the early stage of label design, the force situation in the paper direction was also considered, and the width of the waste edge in the paper direction was appropriately widened to effectively avoid the situation of waste edge breakage.
Sometimes, another important factor that causes the waste edge of adhesive labels to break is in the front-end design process. Due to the lack of practical production experience among designers, the four corners of the label were designed as right angle edges, and the corner vertices of the right angle label were prone to stress concentration, resulting in the fracture of the waste disposal edge being generated at the right angle. This requires designers to pay extra attention when designing labels in the early stages, designing the four corners into arcs to reduce stress concentration. For labels used on automatic labeling machines, the arc radius of the four corners of the label should be greater than 0.5mm, which is conducive to the smooth peeling of the label during the labeling process and improves the efficiency of the production line.
Improper design of the width of the waste discharge edge can also cause the waste discharge edge to break. The root cause is that the width of the waste discharge edge is not proportional to the circumference of the label. A too narrow width of the waste discharge edge cannot withstand the tension when the label is peeled off, causing the waste discharge edge to break. The width of the waste edge can be adjusted according to the size and shape of the label, ensuring that it is proportional to the size of the label. For larger labels, it is necessary to increase the width of the waste disposal edge to improve their strength; For smaller labels, the width of the waste edge can be appropriately reduced to facilitate label peeling. In addition, for irregular large labels, suppliers can be required to perform stress dispersion treatment during blade design to reduce the impact of waste edge fracture on production efficiency.
For irregular labels with complex shapes, especially those with small sizes and a large number of splices, the length of the waste edge becomes more complex, increasing the pulling force of the waste edge. It is necessary to simplify label design as much as possible and avoid overly complex shapes. For labels that require complex shapes, the design of the waste edge should be optimized, such as increasing the width of the waste edge or changing the shape of the waste edge.
