Scrap edge damage is a common problem in die cutting of self-adhesive labels. In order to avoid the fracture of waste edges, it should be noted that the tensile strength of surface materials should meet the high-speed operation of equipment; In general, the width of the waste discharge edge should be greater than 2mm；; The interface position of die-cutting knife should be accurate and the pressure should be uniform; The waste discharge tension should be appropriate, too large will easily cause the waste discharge edge to break. In addition, the shape of self-adhesive label is also an important factor leading to the fracture of waste edge. Because of the special shape of the special-shaped self-adhesive label and the irregular waste discharge edge, the diameter of the area with more waste discharge on the waste discharge roller will be larger than that with less waste discharge, which will inevitably lead to uneven tension of the waste discharge edge and more likely to cause the waste discharge edge to break.

To solve this problem, the following methods can be adopted: install a balance pressure roller on the waste discharge roller, and properly balance the diameter of the waste discharge edge with external force. Add some lining paper to the winding position with less waste edges to balance the tension of waste edges. Pre-stripping process is adopted before die cutting to appropriately reduce the release force of materials, because the greater the release force of materials, the greater the tension of waste discharge, which is not conducive to the smooth discharge of waste, especially for special-shaped self-adhesive labels. There are two main methods to improve the processing technology and enhance the tensile strength of waste edges: covering the bonding surface with a film to increase the tensile strength of the surface material; The back knife is added to the die-cutting station to die-cut the base paper, so that the waste edge becomes a double-layer structure of the face paper and the base paper, and the tensile strength is greatly enhanced.