Really "excellent" ink forum

Many ink manufacturers are committed to developing better inks. “Excellent” seems to be a more abstract statement. Specifically, everyone is looking for a more versatile, more environmentally friendly ink that can print a richer color palette. For printers, it is well understood that ink is the key to the success of prints, but new types of inks continue to emerge. It is not easy to understand the characteristics of different types of inks and to grasp their usage. In view of this, Dapeng Printing Materials Co., Ltd. held ink symposiums in Hong Kong and Dongguan in mid-August to exchange ideas with the printing industry.

It is not an exaggeration to say that this is a truly "excellent" ink forum. The content of the symposium was quite comprehensive. Apart from three main topics: environmental protection inks, water-based gloss oils and metallic inks, it also talked about the glue and film used in post-processing related to printing products. Speakers, in addition to Mr. Ming Gongrong, the managing director of Dapeng, invited two ink experts from Germany's two 100-year old inks to make a special trip to attend the symposium and serve as keynote speakers.

Green ink surface view

The seminar first invited Mr. John Weeks, Head of Offset Ink R&D, Manager of the German Innika Janecke+Schneemann Druckfarben GmbH (J+S), to explain green inks and UV inks to the people in the field. Inika Corporation was founded in 1843 and has been nearly 160 years old. It is the oldest brother in printing ink companies. The company produces various types of inks for research and development, such as offset inks, flexo inks, spot inks, and UV inks. These inks are suitable for different printing properties such as paper, crepe paper, film, film. In Germany, inks are often developed together with major machine manufacturers such as Heidelberg and Manroland. For example, Heidelberg tests the eight-color bottom machine at a testing center in Germany. Inikka ink is used. For more than a decade, European countries have paid great attention to environmental protection issues, so Inika has developed environmentally friendly inks. According to Mr.Weeks, the ingredients and manufacturing process of Natural Series, an eco-friendly ink developed by Inika, are similar to traditional inks. The biggest difference between them is that Natural Series does not contain volatile minerals that are harmful to humans and nature. Oil, the environmentally friendly ink produced, greatly reduces the impact on the environment and ecology.

Many environmentally-friendly inks on the market are based on soybean oil, but Mr.Weeks pointed out that soybean oil itself is a semi-dry oil and has the disadvantage of being hard to dry. Printers have to add additives in order to speed up the drying process. The ink can be made to penetrate quickly, but the stability of the ink will be reduced, and it will easily affect the final quality of the printed product. While the Natural Series is formulated with linseed oil, flaxseed oil is also a natural raw material, but it is a dry oil, which dries faster than soybean oil, and the printing performance is smooth and stable, the effect is more transparent than soy oil. This eco-friendly ink series, which will be introduced in Hong Kong, is suitable for Offset Sheet Printing (powder paper, book/dumb paper) and can be used to match various traditional inks and spot inks. In summary, Inika's eco-friendly inks can fully achieve the performance of conventional inks.

After explaining the environment-friendly printing ink, Mr.Weeks talked with the person in attendance about UV inks. He said that UV inks have been receiving attention day by day due to features such as wear resistance and improved brightness of printed products. However, the following points should be noted when using: 1. Add as little flume as possible, even if it is to be added, the acid value must also be between pH 4.5 and 5.5; 2. Since UV inks are more viscous than normal inks, they must be agitated frequently; Plates should be smooth; 4. The ink roller must use special rubber raw material, can't contain polyurethane; 5. The blanket should also be the same as the ink roller, choose the material that does not contain polyurethane; 6. Conventional ink cleaning agents are difficult to completely remove UV inks, so special cleaning agents containing ketones are used to treat them.

Waterborne Varnish Applications

The next speaker was Mr. Ming Gongrong of Dapeng who discussed the water-based glue, ink glue and water-based gloss oil. Dapeng has always represented the water-based glue produced by Akzo Nobel in the United Kingdom. Mr. Ming said that water-based and oil-based adhesives can enhance the surface quality of prints, and depending on whether the product is a photopolymer or a matte, they increase the brightness of the surface or have a dull and elegant effect. Water-based adhesives do not require solvents. They are more environmentally friendly than oil-based glues, but people in the industry generally use oily glues. Therefore, in recent years, Dapeng company also has agents Akzo Nobel's oily glue production, the quality is quite good, after the glue written yellow chance is almost zero.

As for the water-based varnish, which mainly consists of synthetic latex and acrylic resin solutions, the water-oil-coated prints have improved wear resistance and brightness, while the prints have luminosity of 50-78%, depending on the printed materials. Depends on the cooperation. Since environmental protection is an increasingly important part of the printing industry, waterborne varnish has an advantage in this major issue. Dapeng's British EF series waterborne varnish is environmentally friendly and meets European and American standards. In addition, it can be used with different devices, or connected, offline, and even more directly on the press. In the past, the quality of waterborne varnish has been very stable and the price has been lowered. It is lower than oil varnish. In addition, it has many advantages such as short drying time, brightness and wear resistance. High degree, low degree of yellowing, wide range of applicable products, and low odor are good choices for improving printing quality.

There are many types of waterborne products, such as ordinary varnish, special-purpose varnish such as anti-mold varnish, varnish that can be directly contacted with food, plastic oil, and poker water oil. There is also a kind of optical matte oil for water-soluble ink fountains. The drying speed is fast. On average, it takes 15 to 20 minutes to dry. Because of its high viscosity, it is used directly on the printing press. The printer can be flexibly deployed without the need to install additional oil units. Mr. Ming, for example, suppose you have a five-color machine and you can use the last set of machines to finish the four-color connection. In addition, Dapeng's EF series UV Varnish is supplied with a matching base oil that can be used in conjunction with double oil-passage units. The light intensity can be 70-85%.

Bling Topstar Metal Ink

The final guest speaker, Mr. Colin Appleyard, is the president of the offset printing business of the German Card Company. Aika's metalStar metal ink series has long been familiar to people in the industry. As Inika, love card also has a hundred years of history, has been holding the production of metal powder line of ears, accounted for nearly 65% ​​of the world's metal powder market. In the past, the company mainly sold gold and silver powders for the manufacture of metal inks. By the 1980s, it further developed the metal ink business.

To make the metallic ink refract the light and make it perform well in the sense of metal, the biggest key is to make gold and silver powder for ink. The traditional method of manufacturing gold and silver powder is to granulate aluminum, copper, zinc and other metal materials at high temperature and high pressure, and then transport these metals to a grinding machine filled with steel balls to make them small. After grinding and screening, too large particles will be sent back to the previous grinding and regrinding. This procedure needs to be repeated several times until a suitable metal powder is ground. The entire grinding process takes a very long time. Mr. Appleyard said that for a single production of 600 kg of gold powder, it needs to be ground with 12 tons of steel balls for 7 hours.

Because these metal powders are ground by steel balls, the thickness is not uniform, and the powder surface is inevitably damaged, and it is difficult to be completely smooth. Therefore, it cannot sufficiently refract light and affect the metallic feeling of the ink. In order to solve this problem, Aika developed a new method to extract the metal end. The metalure, a raw material for the new type of TopStar metal ink, is extracted from a metal sheet, and the metal film is put in a solvent and the metal pigment on the film is peeled off.

This method can produce a uniform thickness of metal powder, and because it is not ground by grinding, so the surface is very smooth, almost 100% completely reflected light, so its high brightness. According to Mr. Appleyard, the metal powder is 100 times thinner than the traditional method. It is used to create high metal ink coverage, and it can be used in post-adding processes such as laminating, UV oil, water oil or hot stamping. The adhesion has a very good appearance. Using seven base inks, it can be equipped with ever-changing colors and can be printed synchronously with general offset inks. However, the cost of the metal powder produced by this method is high, and only 1 kg of powder is produced, and 10,000 m2 of metal thin film is required for production.

After listening to the content delivered by the three speakers, the people in attendance deepened their understanding of the materials and believed that it would be very helpful for them to select the appropriate products for use in the future.