Flexo Printing - the preferred method of packaging printing

In recent years, flexographic printing has achieved great development in China with its unique advantages in the field of packaging and printing. According to relevant department statistics, more than 130 flexographic printing production lines have been introduced in China. In addition, more than 7 domestic printer manufacturing plants have begun to produce narrow-width unit type flexographic printing presses. Flexo printing has been accepted by more and more domestic packaging and printing industry.
Flexographic printing is a type of letterpress printing. Originally called flexographic printing, it originated in the United States in the early 1920s. Since the benzoyl dye ink used was toxic, it has not been developed. Since then, ink manufacturers have started to use it. The accepted and acceptable colorant agent was renamed as Flexo Printing m XOGRAPH ICPRO-CESS at the 14th Packaging Conference in the United States in 1952. It was also translated into Furui Toppan Printing in Taiwan. Since the mid-1970s, due to the advancement of the material industry, especially the advent of polymer resin plates and cermet anilox rollers, it has led to a qualitative leap in the development of flexographic printing. It has become the fastest growing printing method in the world. Especially in the United States, it has been fully developed. Both the printing press manufacturing technology and flexo printing application technology represent the highest level of flexographic printing. Most of the merchandise packages seen in the US domestic market are almost all flexographic products. According to statistics, the current market share of flexographic printing in the United States accounts for 70% in flexible packaging printing; 85% in label printing; 98% in corrugated printing; and 25% in carton printing. It also accounts for 60%, 35%, 85% and 3% respectively in Europe. In the United States, even 20% of newspapers are printed in flexo. These figures are enough to prove the vitality of flexographic printing.
The difference between flexographic printing and other printing methods lies in its unique features. First, the use of a soft polymer resin plate (such as the Cyrel version produced by DuPont) reduces the cost of plate making and shortens the plate making compared to gravure printing. Cycle, and due to the increase in plate manufacturing and plate making technology, cable screens have now reached the level of 175 lines, enough to meet the needs of general packaging and printing; Second, the use of anilox roller transfer ink, because the anilox roller is the transfer of ink The roller is also an ink metering roller, achieving the same short ink path as the gravure printing, and can accurately supply the ink according to the process requirements. At present, the metal-ceramic mesh changing roller adopting the laser engraving has reached the level of 1600 lines, and can accurately control the ink color. The thickness of the ink layer provides an advantageous means; the third is zero-pressure printing, which not only reduces the vibration and wear of the machine, reduces the wear on the plate, but also expands the range of printing media, in particular, facilitates the printing of flexible materials. . Fourth, the narrow-format flexographic printing press has also expanded the function of the printing press. In addition to printing, a large number of post-printing processes can be completed, making the flexographic printing press a production line integrating printing and post-press processing.
The advantages of flexographic printing or its advantages are mainly reflected in the field of packaging and printing. First, the ink is thick and the ink is the same. The flexo ink layer is thinner than the gravure printing but definitely thicker than the offset printing, which is very favorable for the large area color blocks commonly used in printing and packaging products. As the ink is transmitted by the anilox roller, generally speaking, if the condition of the paper is unchanged and the ink condition is No change, no matter whether it is the same batch of products or different batches of products, the ink color can be consistent. This is the most basic requirement for packaging and printing, and this is also difficult for offset printing. Second, extensive use of non-toxic water-based ink printing. Flexo Ink is the only non-toxic ink approved by the US Food and Drug Association in all printing methods. As a result, flexographic printing is also known as green printing and is widely used in food and pharmaceutical packaging, which is beyond the reach of other printing methods. Third, a wide range of printable media. Flexographic printing machines can print all types of paper, and can also print aluminum books, plastic films, stickers, stickers, cellophane, platinum and textiles. The type of printable media is more than gravure printing. In addition to the offset printing method, the rest of the media cannot be printed or printed badly. Fourth, a wide range of product applications. Almost all paper and plastic packaging products can be printed by flexo printing. The printing effect on plastic film can be comparable to that of gravure printing. Due to the softness of the printing plate and the small printing pressure, it is especially suitable for corrugated paper and so on. In addition to packaging products, it is also possible to print books, newspapers, books, magazines, and other publications. At the drupa exhibition in 2000, we exhibited special flexographic printing presses for books and magazines. Fifth, equipment comprehensive processing ability. Almost all narrow-width unit type flexographic printing presses can perform post-printing processing on the same device, such as reverse printing, coating, laminating, die cutting, cross cutting, slitting, punching, punching, fan folding, Automatic waste disposal, etc., can even add a number, bronzing or screen printing unit on the printing unit. Therefore, it is not unreasonable to call a flexographic printing press a print processing line. 6. Low production costs and high economic benefits. Compared with the gravure printing, the plate making cycle is shorter and the plate making cost is low 30Oh; the ink consumption is 30Oh less than that of the gravure printing; the power consumption is 40o/o; the printing speed is fast; the maximum printing speed of the unit type narrow web printing machine is up to 150 feet per minute. The maximum printing speed of satellite wide flexo printing machines is up to 250 meters per minute. The reject rate is lower than that of gravure printing and offset printing. It occupies less production space and has a comprehensive processing ability. Save the labor of subsequent processes; avoid the waste of turnover between processes; thus the overall production cost is low. VII. Small investment in production. Because of the relatively simple construction of the flexographic printing press, the equipment investment is lower than that of offset presses or gravure presses of the same scale, generally saving 30o/o to 40%. In addition, in the case of narrow-width flexo presses, since it has almost all of its post-press processing functions, users have purchased flexographic printing presses, eliminating the need for additional post-press processing equipment such as die-cutting and polishing. This saves some of this investment. At the same time, it also saves space and labor for this part of the equipment. As a result, you can save a single investment in production.
Comparing flexo printing with gravure printing, all products that can be printed by gravure printing can be printed flexographically and can be at or near the quality level of gravure printing. However, flexible materials that can be printed with flexographic printing machines Can not be replaced by gravure; In addition, in terms of equipment investment and use costs, flexo printing is much lower than gravure printing. Undoubtedly, the use of flexo printing and packaging printing production is a wise choice for low investment and high output.
Although flexographic printing can achieve high precision, it is trapped in the embossing method and the reason of the anilox roller's transmission of ink. The high-precision network line image quality still cannot be compared with offset printing. In the field of high-grade pictures and books and periodicals, offset printing is unquestionably superior to flexo printing, but in the field of packaging and printing, flexographic printing has the advantage of offset printing. First of all, ink consistency is the most basic requirement for packaging printing. Offset printing ink ink balance and ink emulsification problems, so the ink consistency has become a major problem of offset printing, and this is the strength of flexo printing; Second, packaging design has A lot of color blocks, icons, offset printing In addition to the ghosting problem, the ink layer is not thick enough. When it comes to large-area spot color blocks, it has to be printed twice or even three times. The ink thickness of the flexo printing is far away. Far more than offset printing. In addition, if there are few positive opening products in the packaging products, each side of the offset or four-platform offset press will have more or less waste edges, and the flexible version will be used to print the edge. The trim is accurately reserved in millimeters, saving a lot of paper. In addition, the use of offset printing of packaging products, printing after the need for glazing, die-cutting and other post-press processing, both the need for equipment and labor, and the use of printing, post-press processing integrated flexography machine, you can complete all at once In the process, the paper roll on one end of the machine and the product on the other end not only saves equipment investment, but also reduces the consumption caused by the turnover between processes and shortens the production cycle. Its efficiency is incomparable with offset printing. In addition, the flexographic printing plate can generally reach 1 million to 3 million prints, and offset printing plates can only be printed with hundreds of thousands of Indian prints. Therefore, although the cost of flexographic plate making is higher, However, the printing plate is also resistant to printing. For long-lived jobs, the average plate making cost of a single product is also flat. Finally, in addition to paper, other printing media cannot use offset printing, even if the paper has a limited range of thickness. In the flexo printing machine, plastic films and metal films can be printed, and the thickness of paper printing is also relatively large.
At present, flexographic printing has been widely used in various types of packaging and printing products. In the United States, self-adhesive labels have become the main products of flexographic printing presses due to the use of automatic labeling machines and the large number of applications of stickers, as well as the characteristics of flexographic printing presses, rotary printing methods, and printing and post-press processing. Flexographic printing presses can perform almost all label printing processes, such as die-cutting, embossing, ejection, glazing, laminating, unrolling, and then flip printing and recalibration. In addition, the printing of packaging cartons is another major source of business for flexographic printing presses, but that is another type of special equipment that differs from label printing equipment from platemaking to printing. At the same time, products suitable for narrow-format flexographic printing presses include paper packaging for various types of goods, folding cartons (for cigarettes, alcohol, medical supplies, cosmetics, health products, etc.), stationery (letters, forms, etc.). Books, etc.), paper bags, paper cups, paper products, wallpapers, etc. Products suitable for wide format flexographic printing presses include all types of plastic films, vacuum aluminized films, and pure aluminum foil packaging products such as liquid packaging, baby diapers, feminine hygiene napkins, daily chemical cleaning products, and medical packaging.
In China, flexographic printing started late and developed slowly. In the mid-1980s, the introduction of simple laminated flexo presses began. The reference to any new technology will encounter more or less difficulties and problems. Flexo printing is no exception. The first is the procurement of various supporting materials. The supporting materials required for flexographic printing are more than other printing methods. Plates, tapes, plate rollers, network rollers, squeegees, ink, etc., were needed several years ago. Imports, and in recent years, the rapid development of flexographic printing has led to the development of related material industries. Some related materials have been produced domestically and can be used as alternatives to imports, such as ink and wash, manufacturers have spread all over the country; anilox rolls and die-cutting cylinders Already produced in Shanghai. Some of them are still imported, such as plates, tapes, etc., but purchases have become as simple as purchasing filmmaking films. Therefore, at present, related supporting tools and materials are not the factors restricting the development of flexo. The second problem is the live source problem. Flexographic printing can be flexible and diverse with respect to the volume of printing batches suitable for gravure printing. However, because of its high printing efficiency, normal startup requires a large source of jobs. Take cigarette packs as an example. A 16-inch flexographic printing press must have at least 100,000 boxes of business a year to feed it. Once again, flexographic printing has its own unique process characteristics. From pattern design to color selection, the strengths of flexo printing should be highlighted to avoid weaknesses in flexo printing. At present, there is still a lack of packaging designers who understand the flexographic process. Many products are directly transferred from offset printing to flexo printing. They cannot avoid weaknesses and reduce the degree of satisfaction of final customers for flexo printing products, thus affecting people's understanding and understanding of Sang version. In addition, the concept issue is also a problem that restricts the development of flexo. In the past few years, there were two very extreme views. At a glance, the flexographic version was so good that it would replace the gravure in the future and it would even replace offset printing. On the second day, the flexographic version was too bad to print only a very small number of products. These arguments have been biased, and the correct positioning of the flexographic plate should be said to be a low-input, high-output applicable technology in the field of packaging and printing. Only by identifying the positioning of the flexographic version, can we find the market positioning.
Many brands of flexographic printing presses have been introduced domestically and most of them are successful. However, there are some factories that have gone blind because they know little about flexo and have more or less blindness, either choosing the wrong size or choosing the wrong configuration. The only way to avoid this is to learn more and fully understand the process characteristics of flexographic printing. Never use the old experience of offset printing or gravure printing to explain the flexographic issue. For example, in terms of size, in terms of offset printing, the larger the number of openings, the better, because the same number of prints can produce more products, while the flexographic version is not, the efficiency is achieved by speed, and the size is appropriate if the job allows it. It means that the small size means that the use of low cost, Imagine, small size from the roller to Dielang Street are small, plate, tape, plate making costs are naturally saved; small size also means that during operation The cumulative error becomes smaller and quality control is easier. Of course, it can't be generalized. The printed plastic film still chooses the satellite type