UV ink and water-based ink technology promote flexographic printing

A century ago, flexographic printing was only a very insignificant and insignificant printing process. At that time, it was also referred to as “animation printing,” because aniline inks were used.

With the application of new materials and improved printing conditions, the flexographic printing process has rapidly emerged. It completely abolished the aniline ink, replaced by solvent-based inks and water-based inks, and the quality of printed matter has been significantly improved and improved. Today's flexo printing process is no longer the same, it has developed into another major printing process following embossing, offset printing and gravure printing.

In North America, the current share of flexo printing in the entire printing market is about 22%. In the packaging industry, flexographic printing has become the dominant printing process, accounting for two-thirds.

According to relevant personage predictions, flexographic printing will still maintain a good momentum of growth. In the printing market for corrugated boxes, labels, flexible packaging, paper bags and folding cartons, flexo printing has grown rapidly, and its market share has continued to rise. Most of these businesses have taken place in the traditional embossing, offset and gravure markets. Grab it.

Anilox technology leads the way

With the improvement of the anilox roller processing technology and precision, the quality level of the flexographic printing process is constantly improving. Ten years ago, the number of screen lines of anilox rollers was generally limited to the standard of 360 to 440 lines/inch, but today it has reached 800 lines/inch, and it may be even higher. The higher the number of anilox roller screens is, the thinner the transferred ink layer is, so it is necessary to use ink with a higher and stronger hiding power, and it is not possible to dry on such fine anilox rollers, otherwise Cause paste version.

In addition, flexo printing has also promoted the development of high-speed flexographic printing presses, but this has some difficulties for flexographic printing systems using water-based inks because high-speed printing presses require a high concentration of pigments in the ink, and The ink is required to have good transfer properties.

The emergence and development of CTP technology has brought tremendous changes to the flexographic printing industry, greatly improving the quality of flexographic prints. The use of laser technology for imaging and plate-making directly on photopolymer plates, together with the use of closed squeegees and ceramic anilox rollers, has become a major development direction and trend of the flexographic printing process, and its main applications Center-imprinted (satellite) printing presses.

UV ink technology thrive

In flexo printing, ultraviolet (UV) UV-drying inks began in the middle of the 20th century, but they have not been developed for nearly two decades, and will continue to maintain an astonishing growth rate. In the flexographic printing of trademarks and labels, almost a quarter of the business is printed using UV inks.

UV inks have no pollution, and there is no problem of volatilization of water and solvents at all. There is no solvent volatilization in the printing process, so the bright color of the printed matter, the small dot enlargement rate, and the good reducibility, the quality of the printed matter can be comparable to the offset printing products. Therefore, the application of UV technology makes flexographic printing completely competitive and competing with offset printing.

In the case of wide flexo printing, there are not many successful examples of UV inks, mainly because the application scope of the wide flexographic printing press is mainly the food packaging industry. People are very concerned about whether UV inks will cause food contamination.

Recently, some people in Europe have discovered benzene from cationic UV inks, which has further aroused people's attention to such problems. Moreover, some UV ink suppliers have abandoned the cationic UV ink business and no longer operate cationic UV inks. Cationic UV flexo inks are ideal for printing on webs that require very high UV resistance, such as fertilizer bags.

Water based inks are widely used

In flexographic printing, water-based inks have the widest range of applications and they have an absolute advantage. For example, water-based inks are used in the printing of corrugated boxes, paper bags, paper products, milk cartons, and the like. However, in the printing compounding of plastic films, although the growth rate of water-based inks is relatively slow, it still maintains a certain growth trend. In addition, water-based inks are expected to show new growth points in folding carton printing and some current gravure printing businesses.

In recent years, the voice of environmental protection has been high, and governments of various countries are also continuing to take measures to protect the environment on which human beings depend for survival. They have successively formulated a series of laws and regulations to intensify efforts to control and reduce the emission of organic volatile substances; environmental protection organizations also Ozone emissions are being strictly limited, which ultimately will affect the emissions of VOCs (organic volatiles) into the atmosphere. Such measures have promoted the promotion and application of water-based inks.

In the history of the printing industry in recent years, the rise of the flexographic printing process is one of the most striking events. In the face of various challenges (such as production costs, government administrative regulations, etc.), we must adopt new technologies and find our own way out based on our needs. We must continue to improve and develop with the adoption of new technologies. Flexo printing is a typical example.

The disadvantages of slow drying and poor luster that existed prior to flexographic printing have gradually been resolved successfully with the application of new materials and new technologies. Today's flexographic printing has been a far cry from before. Due to its advantages of high quality, high efficiency, low cost, and no pollution, flexographic printing has a broad application prospect.