ã€Chinese Packaging Network News】 In recent years, flexographic printing has gained rapid development in China with its unique advantages in the field of packaging and printing. According to statistics, at present, more than 150 flexo printing production lines have been introduced in China, and flexographic printing methods have been accepted by more and more domestic packaging and printing industry professionals. Flexographic printing was originally referred to as flexographic printing and originated in the United States in the early 1920s because the use of aniline dye inks was toxic and not developed. Since the mid-1970s, due to the advancement of the material industry, especially the introduction of polymer resin plates and cermet anilox rollers, the development of flexographic printing has made a qualitative leap, and it has become the fastest growing worldwide. The printing methods, especially in the United States, have 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, currently in the United States, the market share of flexographic printing accounts for 70% of flexible packaging printing; 85% of label printing; 98% of corrugated box printing; 25% of carton printing. The market share of flexographic printing in the above-mentioned packaging sector also accounts for 60%, 35%, 85% and 3% respectively. In the United States, even 20% of newspapers are printed in flexographic printing. This is 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 material reduces the cost of plate making and shortens the plate making cycle compared to gravure printing, and due to the plate manufacturing level and plate making. With the improvement of technology, the cable version can now reach a level of 175 lines/inch, enough to meet the needs of general packaging and printing; the second is the use of anilox roller, the anilox roller is both the ink transfer roller and the ink metering roller, achieving Gravure-like short ink path, and can accurately provide ink according to process requirements, the current use of laser-engraved metal ceramic anilox roller has reached 1600 lines / inch level, for the precise control of ink and ink layer thickness provides an advantageous means The third is zero-pressure printing, which not only reduces the vibration and wear of the machine and the wear of the plate, but also expands the range of printing media, in particular, is conducive to 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, can complete a large number of post-printing processes, making the flexographic printing press a production line integrating printing and post-press processing.
The specialty of flexographic printing is the most prominent in the field of packaging and printing, mainly reflected in:
1. The ink layer is thick and the ink is uniform. The flexo ink layer is thinner than the gravure, but it is definitely thicker than the offset printing. This is very favorable for large area color blocks commonly used in printing and packaging products. Generally speaking, if the situation is unchanged, the ink will be used if the ink is transmitted by the anilox roller. If the situation is the same, then the ink color of the same batch of products or different batches of products can remain the same. This is the most basic requirement for packaging printing, and it is also not easily achieved by the offset printing method.
2. Widely used non-toxic aqueous ink printing. Flexo ink is the only non-toxic ink approved by the American Food and Drug Association in all printing inks. As a result, flexographic printing is also known as green printing and is widely used in the packaging of instruments and pharmaceuticals, which is beyond the reach of other printing methods.
3. Wide range of printable media. Flexo printing machines can not only print all kinds of paper, but also can print aluminum foil, plastic film, self-adhesive paper, self-adhesive film, cellophane, metal foil and textiles. The types of printable media are more than gravure printing methods. In addition to the offset printing method, the rest of the media cannot be printed or printed badly.
4. The product has a wide range of applications. Almost all paper and plastic packaging products can be printed by flexo printing, and the printing effect on plastic film can be comparable to that of gravure printing. In addition to packaging products, newspapers, books, magazines, and other products can also be printed.
5. 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 press a print processing line.
6. Low production costs and high economic benefits. Compared with gravure printing, the flexographic platemaking cycle is short and the plate making cost is 30% lower; the ink consumption is 30% less than the gravure; the power consumption is 40%; the printing speed is fast, and the printing speed of the general unit type narrow web printing machine can be Up to 150 meters per minute, the printing speed of satellite wide flexo printing machine can reach more than 350 meters per minute; scrap rate is lower than gravure and offset printing; occupy less production site; comprehensive processing ability is strong, once formed, saves the following process Workmanship; avoids the waste of work flow between processes.
7. Small investment in production. Because of the relatively simple structure of the flexographic printing press, the equipment investment is lower than offset presses or gravure presses of the same scale, which can generally save 30% - 40%. In addition, in the case of narrow-width flexographic presses, due to its own Almost all of the post-printing functions allow users to purchase flexible printing presses, eliminating the need for additional post-press processing equipment such as die-cutting and glazing, thus saving on this investment. At the same time, it also saves space and labor for this part of the equipment.
Comparing flexo printing with gravure printing, all products that can be printed by gravure printing can be flexographically printed and can be at or near the quality level of gravure printing, and flexible materials that can be printed with a flexographic printing machine However, it cannot be replaced by gravure; in addition, in terms of equipment investment and use cost, the flexographic printing method is much lower than the gravure printing method. 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, due to the embossing method and the anilox roller, the high-precision screening image quality cannot be compared with offset printing. In the field of high-grade albums and book printing, offset printing is undoubtedly 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, therefore, ink consistency has become a major problem of offset printing, and this is the strength of flexo printing. Secondly, the packaging design has a large number of color blocks and icons. In addition to the ghosting problem, the ink layer is not thick enough. When it comes to a large-area spot color block, it has to be printed twice or even three times. The flexographic printing ink The thickness of the layer far exceeds offset printing. In addition, if there are few positive opening products in the packaged products, the first printing will be more or less scrapped by the offset or four-platform offset press, and the edge printing may be achieved by the flexographic printing method. Precisely reserved for the millimeter, so as to save 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 The technology not only saves equipment investment, but also reduces the consumption caused by the turnover between processes, shortens the production cycle, and its efficiency cannot be compared with offset printing. In addition, flexographic printing presses can usually reach 1 million to 3 million prints, and offset prints can only be printed in hundreds of thousands of prints. Therefore, although the cost of flexo plate making is higher, The durability of the material is also high. For long-lived jobs, the average plate-making cost of a single product is also flat. Finally, in addition to paper, other printing media should not use offset printing, even if the paper also has a certain range of thickness limitations. In the flexo printing machine, plastic films and metal foils 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, stickers are the main product of flexographic printing presses. Flexographic printing presses can perform almost all label printing processes, such as die cutting, embossing, waste disposal, glazing, laminating, unwinding and then flip printing and re-adhesion. In addition, the printing of packaging cartons is another major source of business for flexographic printing presses. Products suitable for narrow flexographic printing presses include paper packaging, folding cartons, stationery, paper bags, paper cups, paper cutlery, wallpapers, and the like for various types of products in addition to labels. Products suitable for wide format flexo presses include all types of plastic films, vacuum aluminized films, and pure aluminum foil packaging products.