The hottest technological progress promotes the de

Technological progress promotes the development of uv/eb inks

application status of uv/eb inks in recent years, the European market has gradually increased the demand for radiation fixation 6 and lap sample inks and coatings, especially in the industry where the use of uv/eb inks such as packaging can promote their own brands. However, technical problems restrict the vigorous promotion of uv/eb ink in the printing field. These problems not only come from ink manufacturers, but also from relevant equipment manufacturers and chemical manufacturers

as long as these difficulties are overcome, it is very easy for UV/EB ink to replace water-based ink with its most environmentally friendly and viable advantages. Now, there are still some problems in the practical application of UV ink, such as odor, adhesion, printing speed, and the high cost. Since UV ink began to be widely used in the printing industry in the 1970s, all these problems have limited the further development of UV ink

the European Union recently published relevant legislation on the standard of organic volatile substances, which imposes new restrictions on the standard of organic solvent volatilization. The most ideal solution for this bill seems to be the use of water-based inks. However, water-based inks have been questioned by printers because of their low printing quality. At the same time, ink suppliers, equipment suppliers and auxiliary material suppliers are working together to overcome the shortcomings of NUV system and make the radiation curing system more efficient and economical

at present, the share of radiation curing in the whole printing market is less than 10%, mainly because it is difficult to promote in offset printing and narrow web flexo printing. According to the report of Pira Consulting International on radiation curing, in the European packaging industry, the application of UV/EB inks in the offset printing field accounts for about 65%, that is, half of the UV/eb~ inks used in the whole packaging field. According to Pira's report, it is estimated that 80% - 90% of UV flexo printing ink is used for packaging printing, and a large part of it is used for narrow web label printing

however, in the field of gravure digital printing and silk screen printing. The occupation rate of UV/EB ink is relatively small. Nevertheless, driven by technology, especially in the field of base materials, UV/EB inks have grown steadily in the small field they used to occupy. ELTEX, a German company engaged in static electricity control, has developed a technology for neutralizing static electricity generated in the printing process. This achievement greatly increases the application efficiency of UV ink in sheet fed and web offset printing, and also reduces the cost. The key to ELTEX's technological innovation is that compared with many other UV systems, the demand for photoinitiators is reduced by 1% - 3%, and its performance effect is 10% higher than that of other systems

the improved technology developed by ELTEX is very popular in the gravure field, especially promoting the development of packaging UV gravure inks. " Ajit Vaidya, technical coordinator of era organization, said that the trademark owner's output of domestic diaphragms reached 1.2 billion square meters in 2016. He hoped that the printer would use UV ink for packaging and printing to make the prints have a strong visual effect

technological progress promotes the development of UV/EB inks

technological progress promotes the application of radiation curing inks in inkjet printing. Sericol has introduced UV ink into the field of ink-jet printing, which can be used on paper, paperboard and a series of polymers, such as PVC, polycarbonate, polypropylene, polyethylene, etc

one advantage of using UV ink in the field of digital printing is that the ink can be cured only under the irradiation of UV light, which avoids the blockage of the inkjet head and prolongs the use time. The disadvantage is that the printing operator has to wait a day to determine whether the ink is completely dry. In addition, the digital printing equipment will be created by the engineers of the company. The manufacturers often decide the choice of equipment inks to match the special inks for the equipment, which limits the application of UV inks and other inks in the field of digital printing

now, ink manufacturers and chemical companies are committed to developing surface modifiers to enhance the adhesion of ink on substrate. The poor adhesion of radiation drying ink is a very complex problem Especially for the printing of polymer substrate materials. Ciba company has recently developed a new system prime RIT, which can increase the surface tension by grafting a photoinitiator on the polymer. Photoinitiator can form a binding point between ink and polymer surface under UV irradiation

slcpa company has begun to develop a product containing double bonding points, which is composed of isocyanate prepolymer, which can connect the substrate and ink into a whole under the irradiation of ultraviolet light

Italian nanotecsrl Cosenza company has developed an aerosol system, which is composed of gas, solvent, liquid and solid, and can form a thin layer of nanometer thickness. This is different from many other UV inks. These thin layers have low shrinkage. They can be coated with a layer of aerosol on the flat web, sheet fed paper and paperboard through an automatic nozzle, or they can be coated with aerosol on the designated parts through a rotating template. On plastic films such as polyethylene, polypropylene and pet, multifunctional polymers can be successfully attached to the grafted surface through an aerosol

nanotec company acknowledges that in the field of packaging, aerosol still needs to be further improved in many aspects, so that it can be used more effectively under the printing conditions of more than 200 meters/minute. Because now the speed of many packaging and printing is more than 350 meters/minute

uv/EB ink challenge and Prospect Analysis

now, the biggest problem of radiation curing and drying is how to solve the efficiency of high-speed printing and the adhesion of ink on the substrate, which are difficult to be solved at the same time under the existing technical conditions. A feasible way to solve the adhesion problem of UV ink is to improve the viscosity of the ink. However, increasing viscosity means a decrease in printing speed. The high molecular weight molecules in the ink will not shrink under the irradiation of U V lamp, which is one of the main reasons for the low adhesion of the ink. Georg Bolte, who wrote the report on radiation drying inks for Pira, said, "high molecular weight inks usually composed of acrylic polymers have good high temperature resistance, which is conducive to the curing of inks." He pointed out that ink suppliers are reluctant to enter the high viscosity ink market, because now printers generally prefer to use low viscosity inks in order to improve printing speed. "

radiation curing ink is the most promising in the field of medium web flexo printing. In this field, UV ink can dominate as in the narrow web field. Bhsdruck veredelungstechi1ick, a German Flexo machine manufacturer, pointed out that in order to meet the needs of users, most of their medium web printing machines are equipped with UV equipment. Compared with 5 years ago, this proportion was only 10%. Mr.bolte said: the new medium web flexo printing machine is equipped with The electronically controlled power system can achieve better temperature monitoring, which enables the printing machine to print on thin polyethylene film, and can also use UV drying

however, if radiation curing inks are to be widely used in the printing field, greater progress must be made in technology, such as solving problems such as adhesion. Water based inks also have adhesion problems, especially for polymer substrates. " Compared with water-based UV ink has many advantages, especially its high temperature resistance and wear resistance. " Mr.bolte said, "once problems such as ink adhesion are solved, the development prospect of radiation drying ink will be broader."

reprinted from: Printed today, compiled by Sean Milmo, Wang cancai