Narrow web printing application scheme for label printing

Narrow web printing technology has benefited from the label market's annual speed increase of more than 30% and the ever-changing changes in the labeling and packaging market. It has become a wonderful work in printing industry in recent years. The so-called narrow web rotary printing press generally refers to a rotary printing device with a web width of 20 inches (508 mm) or less, wherein a flexographic printing press is mainly used. It also includes rotary offset printing, rotary screen printing, rotary gravure printing and rotary special processing equipment. Such as rotary hot stamping, cold stamping, laminating, transfer, die cutting, slitting and rewinding, super glazing and so on. Therefore, the combination of multiple processes becomes a distinctive feature of narrow-width rotary machines. Because of the different tension requirements and pressure requirements between different processes, the control of tension and printing pressure becomes the key to achieving multi-process combination printing.

Technology Status and Application

At present, with the development of technology, many equipment suppliers can provide combined equipment for flexographic printing + rotary screen printing units, but not all combinations of processes are realized on a single production line. Narrow-width rotary printing has very obvious technical features: a variety of processing methods, flexibility, diversity, high quality, high efficiency, and cost savings, which indicates that narrow-width rotation technology has the superior characteristics of various processes, at the same time, The relatively high overall cost of medium- and wide-width equipment is avoided. Therefore, it is particularly suitable for the needs of the following markets.

1. Label market

The narrow-width rotation equipment and process are suitable for label printing fields including clothing hang tags, cosmetics labels, toiletries labels, wine labels, and cigarette labels. In the label printing market, with the increasing number of varieties and the increasingly complex process, the process requirements are also more stringent. Self-adhesive labels, film labels and other requirements for narrow-width rotary label printing have their own priorities.

(1) Stickers

For ordinary stickers, generally flexographic printing is the main method, and then the connection with die cutting and slitting devices: For special requirements of printed matter, you can also consider adding screen printing device. Printing for some special effects. For sticker products, in fact, more issues need to be considered in terms of production efficiency. Therefore, high-speed flexographic printing equipment has become the first choice. In addition, for ordinary adhesive labels, special process units such as Super glazing can also be selected to achieve uV glazing such as mirror effects to increase the added value of the products.

(2) Film labels

For thin-film labels, it is necessary to consider how to eliminate film deformation and static electricity in the equipment configuration. There are two main causes of deformation, one is tensile deformation and the other is thermal deformation. To solve the problem of film deformation, we must first choose a material with good quality and good uniformity. Second, in the equipment configuration, the best choice for cold uV curing method, not only fast curing speed, but in theory will not make the material deformation. In addition, we must consider whether the device has a device to distribute tension, such as the main power of the drive roller or roller device.

In recent years, the most popular product in the label market is the in-mold label, which is a special film label that can be integrated with the bottle body during the container molding process. The beautiful decoration also has a very good anti-counterfeiting performance. Although this product has a very high added value. However, it is difficult for manufacturers to achieve high added value in actual production. The reason is that in addition to the requirements for printing equipment and film materials, these labels also need to solve two prominent technical problems, one is to eliminate static electricity. The second is high speed die cutting.

The generation of static electricity is caused by the in-mold label material, and the solution is to use static elimination devices to control. Recently, some ink suppliers have provided a static-free ink, such as the uV destaticizing ink provided by Anoye for in-mold labels. It can effectively prevent the generation of static electricity and ensure good printing performance.

Die-cutting speed and precision are another difficulty encountered in the process of in-mold label printing. Since the in-mold label generates a large amount of static electricity in the production process, and the stiffness of the film itself is low during die-cutting, the fly-through phenomenon is likely to occur. Therefore, in the optional equipment needs to be equipped with a professional suction conveying device or in-mold label receiving device.

In addition. The application of cold stamping and screen printing units will also greatly increase the added value of in-mold label products.

2. Packaging market

Narrow web printing equipment is also suitable for a variety of packaging markets, including food packaging, cigarette packaging, beverage packaging, and the like.

3. Special lottery market

In the field of security ticket printing, narrow-width rotary printing equipment also has a lot to do, such as the application of scratch-type lottery printing.

Solution introduction

After analyzing the above basic equipment configuration, we will discuss specific solutions. The total solution of label printing is divided into offline mode and connection mode. The off-line solution is suitable for complex and varied short-run products, due to the small number of products and complicated process. The off-line mode can make the best use of the efficiency between different processes; the connection solution is suitable for the medium and long version products, the process is complicated, because the product technology is relatively stable, the connection method can maximize the production line production Efficiency and product stability.

In view of the higher quality printing of cosmetic labels and in-mold labels on the market today, we propose the following two typical printing solutions.

1. Flexible printing-based solution

In the first printing station, we recommend the use of screen printing, hot stamping or cold stamping in the middle, followed by a set of screen or flexo printing units, and the final process is die cutting or winding. UV curing.

The advantage of this combination is that, under normal circumstances, most of the films for cosmetics labels are transparent. Therefore, the first color group adopts the screen printing method, and the opaque white ink is printed before the color images are printed, which can make the color images more vivid. For clarity, and because of the opaque white as a basis, the reduction effect of graphic printing will be more prominent. Graphic printing uses flexographic printing. Hot stamping and cold stamping can increase the added value of the product. Finally, the use of screen printing or flexographic printing unit for glazing. Since this solution is aimed at film labels, cold uV can be used to increase the servo water cooling roller to distribute tension, and static elimination and die-cutting air suction devices must also be considered. At the same time, this scheme can also increase the gravure printing unit. Under normal circumstances, gravure printing uses hot air drying; this configuration can also achieve some special metal ink printing. This configuration can also basically meet the printing needs of in-mold labels. From the investment point of view, the total investment is small, suitable for small and medium enterprises.

2. Adhesive and flexible solution

This solution still uses rotary screen printing at the first printing station, followed by an offset printing unit that can be interchanged with flexographic printing for printing color images: a set of gravure printing units can also be used later to obtain metallic ink. Special effects; followed by a set of screen printing units for glossing or special effects printing, followed by a set of flexo coating units i with the same die-cutting and rewind units.

The advantages of the program are: low offset printing cost, good dot printing effect, and more suitable for printing high-grade products; at the same time, due to the use of rotary screen printing to print opaque white ink before offset printing, the printing effect of offset printing is guaranteed, and in After adding a gravure printing unit, the integrity of the process is further enriched. In this program, it can also be equipped with hot stamping, cold stamping and other processes. One of its more prominent features is that these process units can all be interchanged to achieve maximum process flexibility.

The program can meet all the process needs of Ping, and can adjust the process at any time based on the changing market, with a very strong market competitiveness. However, its investment scale is also relatively large. Suitable for some larger label printing companies.