Die cutting is an important process in the production of self-adhesive labels, and it can be said that the vast majority of labels require die cutting before they can be finally formed. At present, there are various types of equipment used for die-cutting self-adhesive labels in the market, making it difficult for label printing companies to choose. So, what are the advantages and disadvantages of different styles of adhesive label die-cutting equipment? How should label printing companies choose when purchasing these die-cutting equipment? This article explores the above issues with everyone.

According to different working principles, the mainstream adhesive label die-cutting equipment in the current market can be divided into six types: circular pressing, flat pressing, oblique pressing, combination type, laser, and digital die-cutting.

01、Circular pressure circular die-cutting equipment

The die-cutting tool used in the circular pressure circular die-cutting equipment is a carving knife roller, or a magnetic knife skin is attached to the magnetic roller. Due to the use of a knife roller instead of a flat die-cutting knife, the knife appears circular when viewed from the side. During die-cutting, the knife roller and the imprinting roller are pressed together, appearing as if two rollers are pressed together, hence it is called circular die-cutting.

In fact, there is a small gap between the knife roller and the imprinting roller, and the width of the gap is exactly the thickness of the adhesive material base paper, while the surface layer and adhesive layer of the adhesive material are completely cut off. Due to the fact that the outer circles of the two rollers of the circular die-cutting equipment are almost tangent during operation, this line contact method allows the relative runout range of the plate roller and the impression roller to be controlled within 3 during operation μ Within m, the die-cutting pressure is relatively stable and suitable for labels with high requirements for die-cutting quality. For example, for labels that require high-speed automatic labeling, the labeling speed is fast and the label is subjected to a large tensile force. It is required that the label base paper should not be cut, otherwise it is easy to break during the labeling process. For this type of label, circular die-cutting is the best die-cutting method.

According to the operation mode, the mainstream circular cutting equipment in the market can be divided into two categories: intermittent circular knife cutting equipment and fully rotating circular knife cutting equipment. The intermittent circular knife die-cutting equipment adopts reciprocating paper feeding (equipped with a servo motor controlled swing rod, which causes the material to move back and forth through the movement of the swing rod), that is, when the plate roller is turned to the die-cutting position, the material moves forward, and when the plate roller is turned to the blank position, the material moves back.

The advantage of this design is that it can use the same plate roller to die cut products of various lengths, but the premise is that the maximum length of the product cannot exceed two-thirds of the circumference of the plate roller. Once this range is exceeded, the die cutting speed of the equipment will be significantly reduced. Normally, the operating speed of intermittent paper feeding die-cutting equipment is generally between 40m/min and 60m/min. The fully rotating circular knife die-cutting equipment adopts continuous paper feeding, with a running speed of up to 80m/min~150m/min. However, when die-cutting products of different lengths, it is necessary to replace the corresponding diameter roller, which is costly.

Although the circular die-cutting equipment has relatively stable die-cutting pressure and high die-cutting quality, its tool cost is also high. At present, the price of magnetic knife covers in the market is usually between 250 to 350 yuan/m, and the cost of making a magnetic knife cover ranges from a few hundred to several thousand yuan. If it is to make carving knife rollers, the cost will be higher, with a minimum starting price of 3500-4000 yuan. Therefore, circular pressing and circular die-cutting are more suitable for products with larger batches or different varieties and the same specifications (knife molds can be shared).

02、Flattening and die-cutting equipment

The flat pressing die cutting equipment adopts a flat blade die, with two parallel planes for the die cutting station. The blade die is generally installed on the upper plane and the lower plane is the die cutting platform. When die-cutting, two planes move vertically up and down, and the adhesive material moves under the pull of the traction motor or the paper pulling swing rod. When the two planes are pressed up and down, the die-cutting knife contacts the surface of the adhesive material and cuts through it. This type of device mainly relies on the equipped tracking eye and its own computer program to ensure the accuracy of each paper drawing and ensure the precise position of the die-cutting pattern.

The advantages of flat die-cutting equipment are small size, fast speed, high accuracy, low noise, and low vibration. The mainstream flat press die-cutting equipment in the current market can operate at a speed of 400-450 prints per minute, and the die-cutting accuracy can be controlled within ± 0.2mm. In addition, the price of the blade used in the flat die cutting equipment is relatively cheap, usually only a few tens to a few hundred yuan, and it will not increase the high cost for small batch orders.

It should be noted that due to the design principles of the equipment itself, the stability of the flat press die-cutting equipment is lower than that of the circular press die-cutting equipment. Occasionally, the phenomenon of cutting the backing paper may occur, especially when the equipment is running at high speed, which is more difficult to avoid. Therefore, when it comes to die-cutting products with particularly high quality requirements and large order volumes, there are certain limitations to the flat pressing die-cutting equipment.

03、Oblique pressing die cutting equipment

Oblique flat die-cutting equipment, also known as oblique back die-cutting equipment. This type of device has a certain inclination angle between the upper and lower planes, and its working principle is basically the same as that of a flat pressing die cutting device. Both die cutting is carried out through the up and down movement between two planes. When the two planes are pressed together, the blade plate contacts and cuts through the adhesive material.

The advantages of inclined back die-cutting equipment are fast speed, high accuracy, and lower price compared to flat die-cutting equipment. The disadvantage is that the equipment has a large volume, relatively high vibration and noise, and is more suitable for placement on the first floor of the production workshop. If placed on other floors, it is necessary to fully consider whether the seismic strength of the production workshop can bear this type of equipment, otherwise it can easily cause safety hazards.

At present, although some mainstream die-cutting equipment manufacturers have made corresponding improvements to address the shortcomings of oblique back die-cutting equipment, there is still a possibility of being replaced by flat pressing die-cutting equipment.

04、Combined die-cutting equipment

As the name suggests, modular die-cutting equipment refers to equipment that not only has die-cutting functions, but also other functions, such as flexographic printing, glazing, laminating, hot stamping, etc. This type of modular equipment that integrates all post-press processes is more suitable as a post-press processing center, which can meet the diverse and personalized needs of customers. Enterprises can choose combination units that meet their own needs based on their own order situation, It is even possible to add some special functions to the combined die-cutting equipment to achieve unique functions that other devices do not have.

This combination of die-cutting equipment has many advantages. Enterprises can choose the appropriate die-cutting method based on the die-cutting characteristics of the product, which can be either circular or flat die-cutting, or even a combination of the two die-cutting methods. The disadvantage is that the equipment cost is relatively high. The price of a combined die-cutting equipment ranges from several hundred thousand yuan to several million yuan, and the specific functions need to be customized according to the needs of the enterprise. Some small-scale label printing enterprises with insufficient economic strength often do not have the ability to purchase.

05、Laser die-cutting equipment

Laser die-cutting equipment is a device that uses a computer program to control the cutting of materials by a laser beam. The advantage of this device is that there is no need for a knife mold, and it can achieve a variable die-cutting shape for each label. Due to the variable printing characteristics of digital printing machines, laser die-cutting equipment and digital printing machines have become the best partners, suitable for production of ultra short orders and small batch, personalized orders. In addition, compared to traditional die-cutting equipment, laser die-cutting equipment can also die-cut various complex patterns, such as complex map shapes with die-cutting lines.

The disadvantage of laser die-cutting equipment is its high cost. Generally, laser die-cutting equipment with good die-cutting quality is priced at around one million yuan. At the same time, due to the heat generated by the laser when cutting materials, for some relatively soft film type adhesive materials, such as white PE materials, die-cutting may cause material edge shrinkage or yellow edge problems.

06、Digital die-cutting equipment

Digital die-cutting equipment is a new type of die-cutting equipment that has emerged in recent years. This device controls the blades on the robotic arm through a computer program, and uses the blades to cut the desired shape on the material. The advantage is that it can perform variable die cutting, has lower tool costs, and does not generate heat during the die cutting process. It belongs to the cold die cutting method, and will not cause shrinkage and yellow edge problems of thin film materials. However, the mainstream digital die-cutting equipment in the current market is relatively slow and only suitable for small batch orders.

Above, the author introduced the advantages and disadvantages of six mainstream die-cutting equipment in the market. How should label printing companies choose die-cutting equipment that is suitable for their own product characteristics? In the final analysis, it is still necessary to choose based on one's own order situation and product structure.

If the enterprise mainly orders in large quantities and has high requirements for die cutting quality, it is recommended to choose circular pressing die cutting equipment; If enterprises mainly focus on small and medium-sized batch orders and have relatively low requirements for die cutting quality, they can consider purchasing high-speed flat pressing die cutting equipment; If the enterprise mainly accepts ultra short orders or personalized orders through the internet, it is recommended to choose digital die-cutting equipment; If the enterprise mainly focuses on digital printing, it is advisable to consider configuring laser die-cutting equipment; If the enterprise is mainly engaged in producing products with complex processes, and there are many and complex post-press processing processes, it is recommended to choose modular die-cutting equipment.

Nowadays, many label printing companies have more than one or even more types of die-cutting equipment, and the most suitable die-cutting equipment can be selected according to the specific situation of the order during production. It can be foreseen that with the continuous development of the production process of self-adhesive labels, combined die-cutting equipment will become the main die-cutting equipment for label printing enterprises.