Surface materials affect the die-cut quality of self-adhesive label materials

Self-adhesive material is a kind of composite material composed of face material, adhesive, silicone oil coating and backing paper. Die-cutting of self-adhesive material is different from traditional printing material, such as paper die-cutting, cutting the material as a whole; The die-cutting of the self-adhesive material merely cuts through the face material and the adhesive layer, leaving the silicone oil coating on the backing paper and the surface, and finally leaving the die-cut label on the backing paper.

Die-cutting quality of self-adhesive materials is related to many factors, such as die-cutting mode, precision of die-cutting device, and precision of die-cutting plate. The die-cutting quality is also related to the properties of the self-adhesive material, such as the properties of the paper, the adhesive and the backing paper, and the die-cutting characteristics of various adhesive materials are also different. The following is a brief introduction to the effect of the surface material, adhesive, and backing paper on the die-cutting quality of the self-adhesive material.

1. Types of face materials <br> Surface materials can be divided into two major categories: paper and film. The cutting principle of plain paper is slightly different from that of film materials. During die cutting, the face material and the adhesive must be cut through. The die cutting paper material is the combined result of the cutting of the tool and the stress fracture of the paper. The downward cutting of the blade also presses the paper to both sides, so the paper material The die-cutting accuracy is not very high. When you analyze the sample, you will see some labels with burrs. This is the phenomenon that the fibers of the material are thick and break naturally.

Based on the die-cutting properties of paper-based materials, the angle of the flattening die-cutting blade is generally defined as 520 considering the wear of the cutting edge. If the angle is large, the material will be greatly deformed and the horizontal separation force will fracture the material. The phenomenon has intensified.

The die-cutting of film materials is a complete cut through process. Because most of the film-like materials have toughness and will not break naturally, they must be completely cut through or cut through four-fifths of the thickness, otherwise they will be peeled off along with the labels when they are discharged.

The cutting edge of the die-cut film material should be sharp and the hardness should be high. Using a small-angle die cutter, the blade angle is usually 30-42 degrees. If a large-angle die cutter is used, not only is die cutting difficult, but if the blade is not sharp, the surface material will not be cut and the bottom paper will break. This will cause the edge of the finished label to have a flanging phenomenon, resulting in seepage. In short, the precision of die-cut film is higher than that of paper-like materials.

2. The strength of the face material <br> The strength of the face material is related to the thickness of the face material, the structure of the fiber (polymer) and its own humidity. In the die-cutting process of adhesive materials, the biggest factor associated with the surface material is the waste speed. The greater the humidity of the environment, the weaker the strength of the material itself after being exposed to moisture, and it is easy to pull off, or even to waste. When designing the layout, it is necessary to rationally arrange the waste size and waste removal speed of the label according to the strength of the material.

3. The thickness of the surface material <br> The thickness of the material directly affects the depth of die-cutting. The thicker the material, the easier it is to die-cut. Relatively speaking, the material is thin, and it is easy to cut through the bottom paper. For example, on the same flat-pressure label cutting machine, die cut 80g/m2 and 60g/m2 respectively, the same surface material of the bottom paper. The results of 80g/m2 material die-cutting waste normal, and 60g/m2 material, die-cutting often appear waste fracture. The bottom paper cuts through and drops the mark, often stops and is very wasteful. If circular die cutting is used or the die cut area is reduced, using highly accurate equipment, etc., this phenomenon can be reduced or avoided.

When cutting thin surface materials, it must be carried out on high-precision equipment, reduce the die-cut area (especially small labels), use the die-cut version of a professional die-cut manufacturer, and pay attention to the accuracy of the offset plate. The thickness of the face material is proportional to the strength and directly affects the speed of waste discharge.
Source: Coinprint