The world's demand for UV printing is rising, especially in Europe, the United States and Latin America. According to European equipment manufacturers expect: UV models will reach an annual growth rate of 7%, UV drying device annual growth rate of 10%, UV ink and glazing oil growth rate of the fastest, will reach 14% Of the ink manufacturers statistics, the local market every year, UV ink and varnish consumption are about 15% growth, this figure is almost the traditional offset printing market, the annual growth rate of ink supplies 10 times.
UV technology applications are also expanding, such as labels, plastic, multi-functional sheet and paper printing, especially in the field of label printing, UV printing is reflected in the unprecedented growth trend, high-speed flexo labels, shrink sets Packaging, thermoforming package effects label printing and so on are using UV technology. In this paper, we will focus on the four aspects of high-speed curing, low thermal effect, wide substrate and high solid content.
1, high-speed curing
Flexographic printing process into China only less than 20 years, the domestic printing companies to use flexo to print the label time is relatively short. Even today, the 21st century, the domestic label printing is still mostly use letterpress printing, the use of flexo is still in the initial stage. However, for the developed countries such as Europe and the United States, their label printing market is already very mature, about 90% of the labels are printed using flexible printing in China, although the flexo printing process is still young in the label, but this label soft Indian way has a strong stamina. According to industry statistics, the current Chinese label market every year at about 30% of the rate of rapid rise in the label market expansion, but also contributed to the rise of the label printing industry.
Flexo printing has become the main cause of the label printing process mainly in two aspects: First, the flexographic printing as a more environmentally friendly printing, ink non-toxic and tasteless, in line with international environmental requirements. At present, many large multinational companies on the product packaging increasingly stringent, basically have been used to print the way to print the product packaging. For domestic speaking, pharmaceuticals, food companies have become the main source of our customers' flexo printing; second, flexo printing in the label compared to other printing methods have more advantages, such as color saturation is high, very much Standardization, spot color performance, more convenient to achieve portfolio printing.
However, the printing speed of the flexographic printing press is usually maintained at more than 100 m / min. The printing speed is 2-3 times that of the most commonly used letterpress printing machine in label printing. In such a high-speed printing environment, the UV curing efficiency becomes The key to the success of printing. Ordinary infrared drying process is far from meeting the requirements of the huge baking equipment, long boring Road is simply the nightmare of the printing business. UV curing curing process, ink printing can be cured in a few seconds, significantly improve the production efficiency, you can omit the baking drying process, and drying equipment is simple, save space, fully suitable for high-speed flexo label production.
2, low thermal effect
The heat shrinkable film label is a film label printed on a plastic film or plastic tube with a dedicated ink. When heated (around 70 ° C) during the labeling process, the shrink label will quickly follow the outer contour of the container Shrink, close to the surface of the container, the shrinking film label is mainly contraction sleeve type label and shrink wrap around the label. Shrinkable casing label is a heat shrinkable film as a substrate, made by printing after the cylindrical label, it has the characteristics of easy to use, very suitable for shaped containers.
Shrink film label is part of the label market, is currently in rapid growth, the market share continues to expand, is expected to grow at around 15%, much higher than the average annual growth rate of about 5% of the market, the development potential is huge, A label printing industry to become a major bright spot in the next 5 years, the domestic heat shrink film market will be more than 20% growth rate.
The production of heat-shrinkable film labels is more demanding on the process, especially when printing heat-shrinkable films, it is very important to control the drying temperature. For ordinary water-based and solvent-based inks, the drying temperature is too high , The material heat shrinkage; temperature is too low, the ink is not dry enough, resulting in the final occurrence of adhesion and back from the dirty and other issues, so the process is quite complex, high scrap rate. For UV curing drying technology, the role of ultraviolet light in the ink under the action of the high molecular material in the moment to form a network of cross-linked, the rapid curing of the ink, the printing material temperature has no effect, the unique cold curing system is very suitable for heat-sensitive materials produce.
Recently, Mimaki company released a desktop UVLED inkjet printer-UJF-3042, the product completely UVLED on the printing ink drying, pure UV drying almost no heat, and even suitable for acrylic plastic and other thermal media to print.
3, widely printed materials
In recent years, the global total volume of cultural paper printing has been declining, but the label packaging printing is still growing, the life of the label supplies ubiquitous With the wide application of labels, printing materials are increasingly used such as polyethylene (PE) Film, polyvinyl chloride (PVC) film, polypropylene (PP) film, metal foil and non-absorbent special materials. And these materials are dense surface, do not absorb ink, if the use of ordinary solvent-based ink printing, you need a certain drying time, usually also need to use dusting, drying rack device or in the ink mixed with other additives, and UV ink completely There is no such trouble. For example, Agfa's Ebene UV inkjet printer claims that, in addition to air and water, as long as the printed material can be placed into the UV inkjet printer, you can directly print up. Applicable materials such as: paper, film, PE, PET, PP, OPP, BOPP, PVC, acrylic rubber, wood, tiles and so on.
4, high solid content
The solid content of the solvent-based ink is about 40%, and the solid content of the UV ink is close to 100% of that of the general ink. The printed ink layer is thick and colorful, and it is very suitable for label printing. Thickness can also achieve raster effect, relief effect.
China's latest UV three-dimensional grating ink UV-1278N, is the use of high solids content of the ink used to print the three-dimensional grating diaphragm The colorless and transparent ink, UV fast curing, curing film is not yellowing, adhesion fastness , Good toughness. Different from the traditional hot-press preparation of the three-dimensional grating process, the new process using screen printing method, the ink printed on the packaging machine 'target = _blank> transparent film, the direct formation of columnar grating graphics; can also be three-dimensional grating ink directly printed In the printed matter, the formation of three-dimensional pattern, but also selectively print the pattern to the local three-dimensional, printed three-dimensional effect of the pattern is obvious, and hot-rolled grating plate comparable to the three-dimensional printing opened up a new method. The printing substrate can be transparent plastic film, such as PVC, PC, PET, can also be paper, metal, glass, ceramics and so on.
Roland's VersaUVLED is the world's first use of safe low-calorie LED light UV inkjet printer, which not only can print yellow goods and black and white five colors and varnish, and the printing quality is very prominent. The machine is mainly suitable for one-time packaging printing and short version of the label printing, can perfectly show the "very rich special effects", whether it is high light effects or texture effects can be presented one by one, and even to reproduce the artificial leather and crocodile skin Texture difference.
In addition, UV technology in the self-adhesive label printing is also popular, at present, the label industry has been widely used UV coating technology to replace the surface coating, self-adhesive label polishing is carried out in the rotary label machine, That is, immediately after printing in the graphic surface evenly coated with a layer of UV varnish. For the use of water-based ink flexographic printing, the polishing process is essential to a process compared with the traditional drying equipment, in the case of UV-free equipment, the use of ordinary ink need to be hot after printing, the drawback is the printing Pattern design is limited. In the UV drying device on the device, you can first print after the bronzing, the ink quickly after drying in the ink on the gold foil, bronzing pattern arbitrary design, free from ink restrictions for high-grade label printing.
In short, UV technology does not require heat, is a pure UV cold curing, suitable for the production of thermal labels; and can quickly cure (curing time can be less than 1 second), high productivity and high production capacity can reduce the storage of raw materials and finished products ; UV technology The entire curing system for the solvent-free system, 100% solvent-free formula, suitable for special effects label production, and VOC-free volatile organic substances, fully meet the requirements of environmental pollution regulations. Can believe that in the near future, technology will become the first choice for more and more label manufacturers.