Flexible packaging is one of the fastest growth areas for packaging. In the US alone, the Flexible Packaging Association reports that sales were $31.1 billion in 2014, or 19% of the total packaging market in the US. With shrink sleeve, retort packaging, pouches and more on the upswing, ink manufacturers are very optimistic about the market.
 
One of the key aspects is the type of technology used. Solvent-based inks remain the most common, but energy curing and water-based inks have their uses.
 
“There are good arguments for solvent-based inks and some of those might reflect in their latest success,” hubergroup’s Heiner Klokkers noted. “We can also observe trends that indicate favorable results for all the other ink systems. Small series products or personalized packaging may not be the strength of a classic solvent-based ink system, for instance. Comparing the sold ink volume may not be the only angle we should take into consideration. Radiation curing ink systems do have a lot of potential to packaging, to printing and to the ink makers.”
           
“Solvent-based is still the dominant ink technology used for flexible packaging applications, which is not expected to change in the near future,” Siegwerk CEO Herbert Forker said. “Alternative ink technologies, like energy curing offset inks, are gaining more importance, especially for short print job lengths. Due to the increasing attention and legal regulations regarding VOC emissions, there is already a growing interest in water-based ink systems. Even if this ink technology is still at an early stage, we expect to see more developments going forward including applications on film.”
 
“The ink technology is mainly solvent-based inks, which are suitable for long print runs on a wide range of substrates,” Masa Nagatsubo, GM, Liquid Ink Business Division of Toyo Ink America, LLC, said. “We’ve also had considerable success with the development of water-based inks. These inks lower the amount of residual solvent in food packages as well as directly reduce the environmental risks associated with VOCs. In today’s marketplace where sustainability has become a priority, it is understandable why there is an increased interest in the capabilities of water-based inks and coatings, and in some cases we see a shift away from traditional solvent-based technologies.”
           
“The primary technology remains solvent-based,” said Deanna Klemesrud, global marketing director-Brand & Promo, Packaging & Narrow Web for Flint Group. “There is growing interest, however in UV – particularly UV LED and EB. However, for now, energy curable technologies remain most strong with narrow web and sheetfed applications.”
           
“Solvent is the dominant ink technology for flexible packaging – wide web. Narrow and medium web printers are having success with water inks” reported Joe Kelly, INX’s R&D director of liquid water-based inks. “The movement to ever thinner ink films applied with low volume flexo anilox rolls negates much of the slow drying considerations inherent with water inks. The advances in flexo plate technology, such as the patterned digital plates, are also beneficial to high graphics printing.”
 
“Solvent-based inks continue to dominate the flexible packaging market, but UV curing/energy curing offerings for the packaging market and applications also are a growing trend, especially EC products where product resistance performance is a key criterion. There is also growing interest in EB lamination in combination with EC flexo printing inks,” said Felipe Mellado, chief marketing officer, Sun Chemical.
           
“Water-based inks are already widely used in certain absorbent packaging applications, such as pre-print corrugated, and are oftentimes used by printers in an effort to reduce waste and emissions,” Mellado observed. “While many claim the key challenge for widespread usage of water-based inks is the lack of acceptable quality levels, the reality is that water-based inks can provide similar end use performance to their solvent-based counterparts in the flexible packaging market.
           
“The key challenge with water-based inks is typically press efficiency, such as limitations on press speeds,” Mellado added. “This is especially problematic with non-absorbent substrates such as films. The press efficiency relates back to the ease of drying solvent-based ink versus water-based ink. The challenge for the water-based inks is simply the time needed for the ink to dry on non-absorbent substrates.
           
“In certain market segments where high speed printing reigns supreme, this inherent constraint of water-borne systems has and will likely continue to restrict widespread or significant adoption,” Mellado noted. “However, in many applications there is growing demand for shorter print runs, and as run length decreases, press speed as the key operational efficiency requirement gives way to change over time. Within these segments, water-based products are certainly viable. The acceptance of water-based inks depends first on the equipment printers are already using and the substrates they are printed on as well as the end-use characteristics to which the product will be subjected.”