In addition to printing, die-cutting technology is also very important for self-adhesive. Die-cutting is the process of cutting the adhesive material into a desired shape using a knife plate or laser. Most of the die-cutting process is half-cutting self-adhesive material, that is, only the surface of the self-adhesive material and the glue is cut without cutting the backing paper. Most of the time, after the die-cutting of the self-adhesive material is formed, the excess surface layer and glue will be discharged, leaving the desired part at the end. The following Laissez-faire laser tells you the common problems and solutions in the die-cutting process:

A, the label with the row of waste edge is brought up

The label phenomenon generated by the discharge side is usually called flying label. The main reasons for this phenomenon are as follows:

1. Continuous die-cutting

Traditional die-cutting tools can not completely cut through the surface of the adhesive material, it is very easy to appear the label by the scrap edge to take away the situation. As a result of die-cutting leads to the label side row phenomenon is very regular, basically stick the label and row of scrap edge in the same position of the label. Multi-mode undercutting with fixed die position. The main reason for this problem is the damage to the die cutter, die cutting pressure is not uniform.

Die-cutting is the most common problem in the die-cutting process of patch materials, and the solution is quite simple, just replace the damaged knife strip or adjust the die-cutting pressure to solve. Here to pay special attention to is that sometimes due to uneven pressure, on some parts of the cutting die will be more serious than other parts of the wear and tear. When using this die-cutting label, the tool surface is not obviously damaged, but also prone to continuous die-cutting phenomenon. The way to determine if the tool wear is severe enough to cause further cutting is to know the depth of die-cutting on the backing paper. If there is a clear indentation on the backing paper, and the surface is continuous, you should consider replacing the die.

2. Adhesive material surface and backing paper release force is too small

The force of the adhesive surface and the base paper combined is called the release force. If the adhesive material release force is too small, it is easy to appear labeling side with the row of edges and the phenomenon. Because the die-cutting process will inevitably occur in the glue cutting process, so the waste edge will produce upward force on the label when stretching. If the release force of the self-adhesive material is less than the tension of the waste edge on the label, it is very easy to occur the phenomenon of flying label.

Due to the release force problems and die-cutting flying label phenomenon, mainly by the raw material production enterprises to adjust the release force to solve. Printers who encounter this situation, by increasing the processing temperature or increase the angle of the scrap, such as methods, if necessary, to replace the material.

Self-adhesive label laser cutting

3. The marking area is too small or special shape

Marking area is too small or complex shape of the label (such as a pentagram-type label) is difficult to automatically release. If you encounter such problems, you can try to raise the release angle (you can change the release angle to iron plate or iron ruler to significantly increase the release angle). If necessary, manual removal is required.

4. Glue backflow makes die-cutting continuous

For many hot melt adhesive or thicken the adhesive coated self-adhesive material, in the process of cutting the die, the glue is cut out by the cutter backflow and bonding together, resulting in a serious adhesive strip pulling, resulting in die-cutting when the sticky edge off. In this regard, the appropriate method to reduce the temperature of the die-cutting process can be used to reduce the reflux of glue. At the same time, the die-cutting knife must be kept sharp, so that the knife head can quickly cut glue and reduce glue reflux. If the use of even machine die-cutting method, can also be appropriate to improve the printing speed to reduce the flow back of glue.

5. Processing temperature is too low

Many label printing enterprises in the winter production and processing temperature is very low, resulting in adhesive material frostbite. Greatly reduce the adhesive release force, resulting in die-cutting flying labels. In this case, the need to improve the temperature of the workshop. Generally speaking, the temperature of the self-adhesive processing workshop in winter should not be lower than 15℃.

Sticker laser cutting

6. Improper discharge method

Improper discharge method also prone to die-cutting flying label. Its main manifestations are: discharge waste station and die-cutting station is too far away, resulting in glue backflow. Discharge roller diameter is too large, resulting in the discharge angle becomes small, resulting in flying mark. The solution to this problem is to adjust the distance from the waste discharge station to the die-cutting station and the diameter of the waste discharge roller.

Second, the row of waste edge fracture

In the die-cutting process, the waste side will often break. If the waste edge breakage occurs frequently in the processing process, will seriously affect the productivity. The reasons for scrap edge breakage during die processing are as follows:

1. The scrap edge is too fine or the horizontal and vertical drainage is not correct.

If the waste edge is too thin, can not withstand the pull of the waste roller, it is easy to break. In general, self-adhesive label row waste edge width is best 3-5 mm. And when the row of waste edge of the horizontal width and longitudinal width ratio is not balanced (for example, the horizontal width and longitudinal narrow), the stress of the row of waste edge is not balanced, but also easy to cause the row of waste edge fracture.

2. Label edge

If the label edge is right-angled, it is easy to cause the scrap edge fracture because the scrap edge tension is more concentrated. On the contrary, if the label is rounded, the edge tension is more dispersed, it is not easy to break; if the edge is right-angled, it can solve the problem that the edge of the scrap is easy to break.

3. Special shape of the label

Some are irregular due to special shapes, such as pentagram labels, trapezoidal labels, etc., and the discharge waste edge shape. Discharge waste edge pulling, the row of waste edge tension is uneven, easy to cause the row of material edge break. If you encounter this problem, you can add padding paper in the process of discharging waste to balance the tension of the discharge waste roller, if necessary, manual cleaning is required.

Laser cutting stickers row of waste

4. Die-cutting knife poor contact

If the interface of the die-cutting knife without waste edge will have small burrs or dents. If the waste side of the row of thin or waste roller tension is too large, it is easy to cause the waste side of the row of fracture.

5. Waste paper roller diameter

In general, the diameter of the waste roller is small, the row of waste angle is large, and the row of waste edge tension is large. Conversely, the waste roller diameter is large, the waste edge angle is small, and the amount of waste edge is small. Therefore, for some fine sizes of waste edge, if the diameter of the waste roller is thin, it is easy to pull off the waste edge. These problems can be solved by increasing the diameter of the waste discharge roller.

6. Gum material problem.

Some rubber strips are too large or unevenly coated with silicon edge can cause the waste edge breakage. Silicon edge coating uneven phenomenon is relatively easy to find, the material itself is too large clutch force, you can try to uncover it by hand, if it is difficult to uncover, it may be due to the appearance of the force is too large. If you think it is not obvious, you can determine whether the waste edge is broken due to the problem of clamping force by replacing the material.