The current situation and trend of flexo preprint
the continuous improvement of packaging requirements requires higher quality carton printing quality
with the improvement of people's living standards, people have higher and higher requirements for commodity packaging. There are only twoorthree colors of commonly used carton packaging, and some simple patterns are printed. This kind of carton has gradually failed to meet the requirements of the market, but due to the limitation of the printing materials of the carton, it is difficult to obtain high-quality printing results directly on the carton. Therefore, as a better solution, carton pre printing has been welcomed by many carton printing plants
at present, the pre printing of cartons in China is still mainly focused on gravure pre printing. Although the domestic gravure printing technology has been relatively mature, it can produce gravure printing machines with a width of more than 2m, which can pre print large-size cartons. However, due to the limitations of gravure printing, gravure pre printing is still not a solution for carton pre printing
in the European and American markets, flexo printing machines are used more than gravure printing to make preprinted cartons. The pre printed roll paper printed by flexographic printing machine can fully meet the requirements of carton printing plants, and flexographic printing has many advantages such as environmental protection, energy saving and strong flexibility, which makes flexographic printing the first choice for carton pre printing
flexographic printing can also print high-quality preprint paper
one important reason why many carton factories use preprint to print paper is that with the joint efforts of all enterprises, they hope to obtain better printing effect through preprint than direct printing. Domestic flexographic printing has not yet fully developed, and flexographic printing has almost become a synonym for "low-quality printing". In foreign countries, the printing effect of flexo printing machines produced by some well-known flexo printing machine manufacturers has been greatly improved, and the registration accuracy can reach ± 0.1 mm, or even higher. In the past, the resin version that plagued flexo printing was deformed after a short time of printing, which affected the printing accuracy, resulting in the problem that "the proofing effect of flexo printing is close to offset printing, but the effect is very poor in mass production". Flexographic machine manufacturers have made great improvements in pressure control, registration control, ink control and so on, which greatly improves the service life of resin plates
satellite wide flexo printing machines can also print high-quality products
now generally referred to as "poor printing quality of flexo printing" in China, in fact, it is because most domestic manufacturers use some unit type narrow flexo printing machines. Although these unit type narrow flexo printing machines have certain advantages in flexibility, such as UV glazing, wire belt roller die-cutting, etc., but in tension control, pressure control Drying control and other aspects still need to be improved. For example, printing points are easy to spread and registration is difficult, many narrow width machine flexographic printing machines have not found a good solution so far. When printing some materials with large width and strong extensibility, it is very difficult to control the registration accuracy because the tension is very difficult to control and the paper is easy to deform. Therefore, when the printing width is large, it is generally believed that flexographic printing machine is difficult to obtain high-precision printing effect
however, the above problems can be well solved if the satellite wide flexo printing machine is used. On the satellite flexo press, the substrate is close to a central large impression roller. Unlike the unit flexo press, the substrate is not stretched in a straight line, so the material deformation is less. Even when printing paper below 50gsm or PE and other extendable materials, it can still obtain higher accuracy. At the same time, in terms of pressure control, the servo motor is generally used to drive the advance and retreat of the plate roller, and the decoder is used to detect the stepping amount, so the pressure between the plate roller and the embossing roller can be properly controlled. At the same time, more and more wide axle load frequencies have significantly increased compared with the previous satellite flexo printing machines. The technology of shaftless transmission is adopted to avoid the mechanical backlash. The overprint accuracy of the machine is rarely affected by the loss of mechanical parts, which can ensure the precision of registration for a long time
advantages of flexographic preprint
on the premise of ensuring that the large-scale paper preprint by flexographic printing can obtain satisfactory printing effect, using flexographic printing for preprint has more advantages than using other methods for preprint:
- flexographic preprint can generally use water ink, UV ink, solvent ink or non solvent ink. When printing some orders that require environmental protection, such as printing beer boxes, food boxes, etc, Ink printing is generally required, but if the gravure machine is used for ink printing, the ink is easy to block the gravure roller. Therefore, flexographic printing machine has more advantages in ink printing, and it is easier to meet the requirements of environmental protection
- in the settlement of satellite type flexographic printing, it is not allowed to use the central large impression roller for electromechanical and electrical dampening machines. The substrate is not easy to be stretched, and it has obvious advantages in printing large width or easy to extend materials. The maximum printing width can even reach 2.8m and good printing effect can be obtained
- the way of flexo preprint can be wired with UV glazing or other special treatment. The machine can flexibly match other functions, with high flexibility
- when the printing width is not very large (less than 1.4m), sleeve type plate rollers and rollers can generally be used, which greatly reduces the downtime when changing plates
the future of flexo preprint in China
although the technology of flexo printing has developed to a quite mature stage, most of the popular ones in China are narrow width flexo printing machines. However, to make flexo printing develop in China, we still need to rely on the wide satellite flexo printing machine to bring more confidence to the industry and change the industry's view on flexo printing. It can be said that if the domestic wide satellite flexo printing machine can't develop, the domestic flexo printing can't really develop! However, due to a series of advantages of flexographic printing machine, it is bound to receive more and more attention from printing manufacturers, and flexographic printing will get greater development in China
Italian flexographic machine manufacturer ute long fiber injection process (hereinafter referred to as "LFI") is a series of system solutions co developed by Klaus mafi for fiber reinforced lightweight structure. It is one of the few manufacturers in the world that can produce wide width satellite flexographic machines. Its wide width satellite flexographic machines supply more than 100 sets to the European and American markets every year, making a special contribution to the development of flexographic printing in Europe and America. At the same time, uteco also hopes to bring more flexo printing technology to China to help China develop flexo printing faster
source: Carton special issue
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