Self-adhesive labels are multi-layer composite structural materials composed of base paper, adhesive and surface materials. Due to their own characteristics, there are many factors that will affect the final use effect during processing and use.
The first problem: the printed text on the surface of the hot melt adhesive self-adhesive material is “shifted”
A company’s double-sided labels printed with four colors on the front and a single color on the rubber side “shifted” after the text on the rubber side was left for a period of time. The investigation found that the company used hot-melt adhesive coated paper self-adhesive materials. As everyone knows, the problem lies precisely in the adhesive. Because hot melt adhesive has strong fluidity, if small text is printed on the surface of this adhesive layer, once the label is slightly displaced during the subsequent compounding and die-cutting processes, the adhesive will flow accordingly, resulting in the printed text on it. Therefore, it is recommended that label printing companies try not to use hot melt adhesive self-adhesive materials with relatively strong fluidity when producing labels with small text printed on the adhesive surface, but choose hydrosol self-adhesive materials with relatively weak fluidity material.
Second question: Reasons and solutions for unevenly folded labels.
The main cause of uneven label folding is equipment tension. Unstable equipment tension will cause the die-cutting knife to swing forward and backward during the die-cutting process, resulting in uneven label folding. This causes uneven folding and the folded labels are arranged in a zigzag pattern. In this case, you can try to increase the operating tension of the equipment. If there is a pressure roller in front of the die-cutting station, be sure to press the pressure roller and ensure that the pressure on both sides of the pressure roller is consistent. Generally, this problem can be solved after the above adjustments.
The third question: Reasons and solutions for label folding and skewing.
Sticker paper folding and skew can be divided into two situations: one is front-to-back skew, and the other is left-to-right skew. If the product appears to be skewed forward and backward after being folded, it is generally caused by the diameter error between the die-cutting knife roller and the transverse knife roller. Theoretically, the diameters of these two rollers must be exactly the same.The error value should not exceed ±0.1mm.
The left and right skew is generally caused by the skew of the dotted line knife. Sometimes when folding appears skewed, we can clearly see that the dotted line knife cuts out a skewed shape. At this time, you only need to adjust the dotted line knife.
Post time: Jan-23-2024