Experience Labels Narrow flexo printing

As one of the largest professional label manufacturers in Jiangsu Province, with the expansion of production scale. With the improvement of label quality requirements, we are deeply impressed by the fact that traditional printing equipment has become less and less able to meet production needs. So in 2002. The company decided to introduce new label printing equipment and chose the Gallas 2 80 type narrow-flexible eight-color printing press to cope with the growing label market demand.

While introducing narrow-width flexographic printing equipment, it also applied narrow-width flexographic printing technology to label production, and through two years of production, it has greatly promoted the development of the company. At present, our label products have been widely involved in many industries such as pharmaceuticals, visualization, and food, and have been praised by well-known manufacturers such as Nais Group, White Cat Co., Ltd., and Onyx. This article only summarizes the experience and experience in our production process. Share and communicate with your peers.

Technical experience

In recent years, the competition in the label market has become increasingly fierce, and users' requirements for label printing quality have been continuously improved. At the same time. Label printing technology advances, equipment innovation. It also provided the basis for the development of the leap in label printing quality. The use of narrow flexographic printing technology. Not only expanded the company's business scope and production capacity. He has established a leading position in the technological competition, and has accumulated rich experience in prepress processing, media selection, network cable production, and flexographic printing technology.

First of all, in terms of pre-press processing, we usually find that when design documents are received, customers design orders that are mainly offset or gravure. This type of original should be printed using a flexographic printing method. There are often many quality problems. If the color is not in place, the level is not obvious. There are hard edges and so on. Therefore, in order to better solve such problems, it is necessary to communicate with customers in a timely manner.

Secondly. In the selection of flexible plates, we must also shop around. Printing companies need to fully discuss with the many well-known plate-making companies in China on the use of media, the production of cable versions, the transition of levels, the compensation for the increase of outlets, and the expansion and contraction rate of printing plates. The data are summarized and the criteria are established to provide reference for daily production. This kind of data management is not only conducive to production, but also can control quality parameters well, avoid interference from human factors, and reduce production failures.

once again. Due to the special nature of label printing, narrow-width flexographic printing equipment is compared to embossing and other types of flexographic printing equipment. With its outstanding features, from our experience, narrow-format flexographic printing equipment is not only simple to operate. Printing quality and operating efficiency. And strong combination. This means that more types of products can be made and more competitive.

Experience exchange

Good equipment also needs correct operation and reasonable maintenance in order to make the best use of it. In the use of narrow-width equipment, the biggest obstacle we face is not technical issues but process problems.

1. Ink does not dry, easy to fall off

For the ink drying problem, we take the solution is. Using a 9-kw UV drying device, it dries easier and faster than a 2kw lamp. Encountered problems with ink falling off easily. We usually work with ink suppliers. Raw material suppliers jointly analyze if it is found that the ink adhesion is not good. Additives can be added. If the surface properties of the substrate are not good, corona treatment is required.

2. Static electricity

Electrostatic problems are often encountered in production. In particular, when printing labels, it is necessary to install a complete set of static elimination devices on the equipment, and strictly control the temperature and humidity of the workshop. Especially when printing in-mold labels and film-type label products, the effect of static electricity and dust removal is better.

3. Bad squeegee effect

Flexo printing process. Scraper and anilox roller synchronous drive. Easy to appear knife wire, that is, there is a strip of ink on the printed label. In the field, there are some places where the colors are lighter than the surrounding colors. At this time, the squeegee should be adjusted to the best angle. On the choice of scraper. Blades of imported scrapers are mostly carbon-fired and have a good scraping effect. The reason for the appearance of ink marks may also be that the ink itself is prone to bubble formation, which is caused by the formation of marks on the anilox roller. In this case, it is necessary to appropriately add some additives.

4. Stick

Labels have dark bars. It is often the gears on the plate cylinder and the impression cylinder, the teeth are not round, or the plates are indented. It is generally necessary to replace the roller gear. This type of failure rarely occurs at higher speeds because the gearing between gears is a very quick momentary contact. Greatly reduce the resistance between gears.

5. Screen number

From the perspective of the number of printing screens, the maximum number of lines for offset printing and gravure printing is higher than for flexographic printing. The ideal screen number for flexographic printing is about 150 lines/inch. If more than 175 lines/inch, it will increase the difficulty of plate making and printing. In particular, when the field and the cable are on the same block, the ink in the field is large, which can easily cause failures such as ink blocking of the anilox roller and shorten the life of the plate. In addition, flexographic printing is totally different from offset printing and gravure printing in the processing of the cable. Offset and gravure dots can be graduated to zero. The minimum flexo printing can only be 2%.

The development of the label market has provided a development stage for flexographic printing technology. The improvement of flexographic printing quality, cost reduction, and process flexibility have in turn promoted the development of the flexographic printing market.

Today, with the development of uV technology, the awareness of environmental protection has been enhanced and the equipment maintenance time has been shortened. The degree of user acceptance of uV flexographic printing technology has also gradually increased. at the same time. Users have also increasingly valued the combination of various printing processes to meet the diversified needs of the label market, which has led to and promoted the emergence and development of narrow-width rotary printing processes. We believe that the maturity of the narrow flexographic printing technology not only promotes the development and progress of the flexographic printing process. It also brought surprise to the development of label printing companies, and its rapid development is a necessity.

Source: China Design Printing Network