Flexo, say the experts, no longer has to compare itself to offset. It now sets its own standards.
By Steve Katz
A movable touch panel provides full press control for the Gallus RCS 330/430.
In the early 20th Century, flexo’s use in the USA was primarily in food packaging, until it was delivered a big blow by the Food and Drug Administration (FDA) when aniline dyes were classified as unsuitable for food packaging. (Flexography was first called aniline printing, because early flexographic inks contained dyes derived from aniline oil, a liquid extracted from the indigo plant.) But through trials, tribulations, and perseverance, and when the FDA approved the process, the printing method caught on. In 1952 it was dubbed “flexography,” by Franklin Moss, then the president of Mosstype Corporation.
Moss polled the readers of his publication The Mosstyper to submit ideas for a new name of the fledgling print process. After narrowing down the possibilities, it was decided it would be known as the flexographic process, in tribute to its origins – the flexible rubber plate used to create the relief image.
Since then, flexo has only grown. Advances in all of the components of the process – plates, inks, anilox rolls, and the presses themselves – have all played significant roles in flexo’s evolution, and they continue to do so today. Flexo is far and away the predominant label converting method in North America and now in Europe. It’s impossible to discuss the label printing industry without talking flexo – not only where it’s been, but where it is now, and where the industry leaders see it going.
Automation and reduction
In discussing current flexo trends, the consensus of industry leaders points to servo technology and automation as major improvements. Automation of the printing process is largely credited with reduction in waste, changeover times, and cost savings, while at the same time leading to an improved product overall.
“The most significant improvement in flexo with regard to waste and changeover times has to be the implementation of servo technology,” says Jeff Feltz, director of product management for Mark Andy, St. Louis, MO, USA. He says registration control is vastly improved through the use of servos, thus leading to a significant reduction in waste.
“Servo technology significantly reduces the number of gears in the press, contributing to improved registration performance and reduced waste. Registration performance is also enhanced by servo tension control, which controls and maintains registration at all speeds throughout the run. Auto registration systems, enhanced by servo technology, also contribute to reduced waste as it takes the responsibility off the press operator to ensure tight registration is maintained throughout the press run,” Feltz says.
Andrew Colletta, president/CEO of Nilpeter USA, Cincinnati, OH, emphasizes how far registration has come. He says that in the past, flexo was used mainly on jobs that were considered easy, and a far cry from what printers expect from the process today. “There was nothing sophisticated about the process in its early stages. Expectations were minimal from printers and customers alike. Print quality was determined by how neon colored ink laid down, and tight registration tolerance was literally non-existent as jobs were relatively easy with minimal registration requirements. Switch ahead to today and we see print quality coming off flexo presses that in many cases is difficult to differentiate from litho. Registration specifications are now extremely tight, and it is not unusual to see registration in the ±0.001" range, again emulating litho quality,” he says.
Servo technology, which eliminates the traditional line shaft/gear box drive systems, Colletta says, has upgraded the performance of flexo presses to new levels, once never thought to be possible. He says, “It has reached a point where one servo flexo press can outproduce two of the conventional line shaft presses with lower waste, lower make-ready times and significantly higher quality.”
It can be said that adding servo technology to a press is a case of subtraction by addition – adding the servo results in not only a reduction in waste, but also in reducing make-ready and changeover times.
Felix Egger, vice president of sales and marketing for Gallus, a press manufacturer based in St. Gallen, Switzerland, says improvements in waste reduction and changeover time are so dramatic, it’s difficult to quantify them. “When looking at the development of changeover times and reduction of waste, it is difficult to put it into seconds and meters. Ink chambers, sleeve systems, front loading, as well as press presetting functions have reduced changeover times from hours to minutes. Furthermore, servo technology and press automation dramatically reduce waste: Job recall to preset the press, and dynamic print pressure adjustment to adjust the printing cylinder’s contact pressure as a function of the speed, are just two examples of waste reduction. The Gallus RCS does not need any manual adjustments when you do a repeat job. All necessary settings are automated and allow easy reproducibility with the least waste. Based on our customer’s experiences, we can say that compared to a traditional press, the productivity of a Gallus RCS is up to 30 percent higher,” Egger says.
A cold foil cassette on a Mark Andy XP5000 platform press
Mac Rosenbaum, VP sales for Aquaflex, a division of F.L. Smithe, located in Duncansville, PA, USA, says, “Servo technology has lifted printing excellence and flexibility to a new standard. Those printers who upgrade to servo presses are finding competitive advantages in the marketplace – they’re printing better and at less cost.”
Eric Hoendervangers, managing director of MPS Systems, Didam, the Netherlands, notes that while servo drive additions to flexo presses are the trend, price and productivity are also playing key roles. “Next to servo drive technology, there’s also a trend toward more expensive press purchases, with converters focused on ensuring improved quality in their products. Long gone are the days of cheap flexo presses producing inferior products. Productivity is the key to addressing price. With margins under increasing pressure, it’s the only way to survive,” he says.
Hoendervangers acknowledges the concentration on waste and setup time reduction, but says that MPS places additional focus on eliminating all quality-related waste. “At MPS, it’s of paramount importance to eliminate all waste that results from quality issues. This waste is often a byproduct of start-up waste. Our Crisp.Dot technology with guaranteed gear marking-free print results generates an enormous amount of quality throughputs.”
Denny McGee, president, MPS America, Brookfield, WI, USA, explains MPS’s approach toward flexo today: “We feel there is a lot more involved in refining the quality and consistency of flexo printing than being a press manufacturer with servo drives. At MPS, we completely separate web transportation from printing via servo infeed and servo outfeeds with separate independent servo transportation of the web at each printing station – we call it frictionless printing. It calls for our impression rolls to be idling rolls (not driven by servo motors, but driven by the web) so we don’t create an interference between web transporting and printing. Then, to give impression setting advantages, we cover these non-driven impression rolls with a hard rubber surface that provides impression setting flexibility and less dot gain. Now we can print closer to offset cures that high end label and packaging print buyers are looking for,” he says.
Whether it’s due to servo technology, ease of use, or improvements in ancillary equipment, one thing is clear – the resulting product, the quality of the printed label today, has reached levels never before seen.
Print quality and flexibility
“Print quality, print quality and print quality,” sums up Mac Rosenbaum of Aquaflex about what he strongly feels is a major theme marking flexo’s development. And he’s been thoroughly impressed with the work he’s seen being done on flexo presses. He says, “In my travels to meet with printers who have upgraded to Aquaflex servo presses, I’m continually impressed with the product diversity and print excellence they have been able to achieve using our equipment. They tell me that it’s like night and day when compared to the printing technology of just five years ago. The precision and accuracy that servo-driven presses deliver has lifted the bar and created incredible opportunities for inline flexo, both in today’s challenging economic times and I believe well into the future.”
Today’s presses and the ancillary equipment and consumables that go with them have not only opened the doors for improved quality, but also for vastly expanding a converter’s product portfolio. “Today, label printers are looking for greater diversification to expand from commodity products into higher-margin specialty products like shrink film labels. That means the presses we build must perform superbly well on a wide variety of substrates including thin films. From the printer’s perspective, there is no room left for ‘good enough’ – everything must be excellent and be priced competitively,” Rosenbaum adds.
Felix Egger of Gallus emphasizes just how radically the developments in flexo technology have altered the label printing landscape. “When print quality reached the point where it is now, press manufacturers took a close look at process flexibility and productivity in flexo printing. Gallus managed to take its flexo printing system to a new level with the introduction of the Gallus RCS with servo drive technology, limitless flexibility in terms of processes and substrates, front loading throughout, sleeve technology, chambered doctor blade ink chambers, and flying imprint – and these are just a few key features that are the foundation for uncompromising print quality, with maximum operational efficiency, based on a pit-stop production strategy,” Egger says, referring to Gallus’ one stop, automated workflow incorporated into its RCS line of presses.
Mark Andy’s Jeff Feltz also agrees that increased flexibility has become a boon for printers. “Platform press solutions offer the ultimate in process flexibility, from screen to cold foil, hot stamp to gravure – thus providing the ability for converters to grow their business and enter new higher margin markets. Incorporation of operator interface terminals at each print station has significantly increased the automation of the printing process, reducing the reliance on manual adjustments. Through automation and improved press designs, the printing process is becoming less of an art and more of a defined process,” he says.
Feltz makes the point that flexo is opening doors to more opportunities. “Improvements in flexo plates, higher line-screen anilox, and servo press technology have combined to significantly improve print quality. Meanwhile, flexographic label printing has become much more than just the flexo process. The incorporation of gravure, digital, and variable-data printing has enhanced the quality and versatility of the resulting label product in ways that had not been considered possible previously. Complex constructions, such as booklets and expanded content labels have become more prevalent as consumer product companies look for creative ways to put more information on the package, both for marketing and regulatory reasons,” he says.
What’s become known as combination printing, the incorporating of other print processes with flexo, has clearly caught on, thus raising the bar on the types and quality of labels that can be produced.
“Flexo printing has come to the point where printers’ expectations for quality and flexibility have been raised to entirely new levels,” says Nilpeter’s Andy Colletta. “Thus, the standard flexo press has gone by the wayside, being replaced by the combination presses which have multi-substrate capabilities as well as multi-processes such as flexo, UV flexo, rotary screen, hot foil, cold foil, and variable data, just to name a few,” he says, adding that flexographic dot reproduction has also improved significantly, becoming extremely precise as a result of upgrades in ancillary items such as plates, anilox rolls, inks and substrates.
Inks, anilox, and plates
Of course, a discussion on flexo trends will have a focus on press technology – what’s new as well as what makes them tick. But the gears and motors are only part of the story. As the industry’s press experts have mentioned, a flexo converter’s improved capabilities are also the result of the advances in flexo’s other key components – the inks, anilox, and plates.
Flexo plate, ink, and anilox suppliers acknowledge the obvious demand for materials that produce superior graphics. But they also must make adjustments in their products in order to keep up with the ever-changing press technology. Not only that, but environmental concerns play a role as well, as flexo converters strive to become more and more environmentally friendly.
CRI continues the development of higher strength pigment dispersions, vital for the formulation of the inks required
for today’s finer line aniloxes.
Another significant trend, Sickinger says, is the move away from specialty niche solvent based inks to water and UV based inks. “The key benefits here are twofold: The reduction in carbon dioxide generation, and the introduction of environmentally friendly inks. Another advantage of using a water based ink is that many of the systems available today are formulated with renewable plant based resins. There is also a trend to use more shrink sleeve labels. These labels do not use adhesives and are easier to recycle than the more traditional products,” he says.
Sickinger also notes specific improvements in ink formulations that are a direct result of flexo’s requirements. He says, “Flexography requires a given film thickness, and the newly formulated inks with increased color strength can easily meet these requirements to deliver high resolution images. Improvements in resolubility contribute to longer and faster runs and increased adhesion of today’s inks to a variety of substrates enable printers to serve a wider range of clients. Recently developed ink systems also exhibit high resistance to a variety of household and industrial chemicals, making label printing impervious to the contents of a bottle they must describe.”
Mike Buystedt, general manager, Midwest, for Flint Group Narrow Web, a Swedish ink manufacturer with US headquarters in Plymouth, MN, says that the use of flexo inks for shrink applications is catching on, with growing interest in UV flexo inks for shrink. “Historically, UV flexo technology could not be used for printing shrink labels. The technology was not flexible enough to provide good adhesion and other required attributes when shrinking the label around the end product. In finding the right materials for UV flexo shrink, we’ve brought to the market a product that has lower maintenance and is more user and environmentally friendly,” he says.
In addition to flexo inks for shrink applications, Buystedt sees other emerging flexo technologies including heat transfer inks and flexo inks for in-mold labels. “Regarding heat transfer, the flexo inks are ‘transferred’ by applying heat onto the container or end use product, and it’s just the ink that remains. In the past, this application was typically done using solvent gravure inks,” Buystedt says, noting that flexo inks for in-mold printing has picked up in the US. “Until now, flexo inks for injection in-mold printing has been mostly used in Europe.”
Additional flexo ink trends that Buystedt’s taken notice of include the use of low migration UV flexo ink for use on primary food packaging and brand security inks. “As counterfeiting threats increase, interest in brand security ink does as well,” he says.
Buystedt says there’s also the trend indicating customers are moving from water based flexo ink systems to UV flexo. “Printers see increased benefits with UV flexo, such as less press-side maintenance, no need to clean up between shifts, more brilliant colors, and zero or very low VOCs. Printers are looking for increased productivity, lower waste, better pricing, and a better end result – a transition to UV flexo can provide these bottom line benefits,” he says.
John Signet, marketing manager, Water Ink Technologies, Lincolnton, NC, USA, also sees an increased interest in security products. “We’re seeing a lot of interest in security inks and coatings. I’d say there is equal interest in covert applications such as taggants, DNA, chemical markers, and energy reactive inks and coatings as there is in overt security products such as color shifting or thermochromic inks,” he says.
Health and safety concerns, Signet says, is another area that’s driving the flexo ink market. “The consumer safety market appears to be driving a concern for safer formulations specifically with regard to heavy metals. Not only are converters wanting to limit their exposure to this and other potentially harmful substances, they are also looking for third party verification of suppliers’ statements regarding the health and safety of their inks and coatings.
“As an extension of this, converters are also looking for inks and coatings that are user friendly and help increase productivity. With water based products, this means press stable formulations and consistent color batch-to-batch. With UV, this means inks and coatings that are safer to handle, have low or no odor, and cure faster,” Signet says.
Directly related to the trends and advances in flexo inks is the tool used to deliver it onto the substrate – the anilox roll. “Improvements in anilox technology have long been a driving force in elevating flexographic print quality,” says David Lanska, Midwest regional sales manager, Stork Cellramic, Milwaukee, WI, USA, and author of Common Sense Flexography. “Ceramic laser engraved anilox supplanted chrome due to improved durability and consistent ink delivery over time. Higher line counts brought enhanced ink distribution through the exponential explosion of cell concentration,” Lanska says, pointing out that the higher line counts facilitated use of improved plate technologies and higher plate screens.
“Intrepid flexographers, in a perpetual push to expand the world of possibilities, combined the anilox and plate with new blade materials, higher modulus stickyback, and a bevy of ink innovations. At the same time, servo presses improved registration while innovative special effects were achieved when multiple print technologies were combined. The results have been spectacular with near photographic image quality combining with cold foil, rotary screen, thermochromic inks, sequential numbering and so on,” he says.
Fiber optic laser technology has created smoother anilox cell wall linings.
(Photo courtesy of Stork Cellramic)
Bill Poulson, technical graphics manager, Harper Corporation of America, Charlotte, NC, USA, says that the anilox has always been the driver for improvement in the flexo industry since the first day the ceramic laser engraved anilox roll hit the market. He talks about recent developments: “There have been many improvements in the anilox roller’s coatings, hardware and software that drives the lasers. The most recent developments have allowed Harper to increase the line screen and get more volume as well. The newer laser hardware has allowed us to get a more bowl-shaped cell, which has allowed for better ink release. A more linear cell wall allows for more volume capability within the cell cavity to support that ink release,” Poulson says.
While improvement in the anilox’s cell wall construction is a major trend, Poulson also emphasizes other facets of anilox technology that converters can benefit from. “Standardizing your inventory is an important mindset within the narrow web world. Narrow web runs an array of anilox line screens and volumes which, if not managed properly, can create press downtime and frustration in the pressroom. The newer laser technology has allowed for less line screen selection needed which promotes the standardization process. A label house can run standard graphics from process print to line work with three or four anilox rolls with only four different volumes,” Poulson says.
And then there are plates, another flexo component that has come a long way. Plates, like presses, have advanced due to automation and innovation. Flexo plate improvement also plays a major role in print quality.
Ian Hole, VP of market development for EskoArtwork, the prepress systems and equipment supplier based in Gent, Belgium, with US offices in Vandalia, OH, USA, says, “Automating the workflow is a major trend in flexo right now, and this includes automation in platemaking,” he says, emphasizing that software workflows have eliminated several steps from the process.
“With the software we have now, people can take the steps they normally take – preflight, ripping, etc. – and automate them all, thus allowing for completely free movement across seven or eight steps. Not only does this result in huge time savings, but also in error reduction,” he says.
Hole says EskoArtwork’s advances in digital flexo platesetting and UV exposure have helped label converters save time and money. “We’ve already gone fully automated in terms of putting the plate on the drum with anything that has to do with UV exposure. What is normally a three step process has become one – without anyone touching it.”
Hole also sees a demand from customers who are increasingly interested in flexo plates that push the frontiers of print quality. “We get a lot of calls from customers about raising the bar of expectations of what flexo can be,” he says, adding that the company has recently developed a CDI imager that heightens results to levels that previously were not available.
“With the use of new screening, we’re able to achieve a very wide tonal range, tremendously smooth and detailed highlights, with graduations going to zero, thus avoiding hard lines. It’s available today and there’s been a lot of interest from our label customers,” Hole says.
Michelle Garza, general manager for RBCOR, a flexo plate distributor headquartered in San Marcos, CA, USA, says, “The main thing about flexo is that it has come so far over the years. We’re finding a lot of companies converting more jobs that would have previously been done by offset.”
She notices some of today’s distinct trends. “Computer to plate (CTP) is one trend. There’s carbon mask, mask laminated, and there’s laser ablation. Ultimately, that’s where I see flexo platemaking going – laser ablation. Digital presses are another huge trend, specifically the Xeikon, and now you’re able to have water washed flexo plates and digital water washed flexo plates that has a carbon mask.”
Garza talks about the more environmentally friendly platemaking alternatives coming onto the scene. “In the past, the DuPont FAST system was the only option if you wanted to go solvent-free. So what’s exciting about water washed is that now there’s something to compete with FAST in an environmental sense, in addition to MacDermid’s LAVA system. Water washed digital flexo plates are now competing up against solvent. Environmentally it’s exciting, and it also tends to be cheaper. The processing equipment is also cheaper,” she says.
Other changes and improvements, Garza says, include the availability of single exposure and wider latitudes for exposure. “Also, there are now safer solvents on the market. It used to be just PERC (perchloroethylene), which is scary. Now, there are much safer options,” she says, referring to alternatives to the chlorinated solvent that studies have shown to be harmful.
“Today there are better ink transfers and printing capabilities, better wear and longevity on press. The solvent and ozone resistance has also improved dramatically. There are also more plates and formulas available for more applications,” Garza says, adding, “We see only growth in flexo, as it’s going to continue stealing customers from offset. Flexo plates now have greater ability to print on all types of substrates where offset can’t.”
No longer the ‘ugly duckling’
Frank Burgos, the producer of the Ugly Flexo video series, playfully named his instructional videos “Ugly Flexo” for a couple of reasons. “For so long, flexo was considered the ‘ugly stepchild’ of the printing industry, so I decided to name the videos Ugly Flexo for that reason, and because I felt it was sort of an endearing, disarming name,” he says.
There are 82 Ugly Flexo videos to date. The presentations are instructional, providing insight on a variety of topics including ink blending, plate mounting, color management, equipment maintenance, and Lean Manufacturing, just to name a few. In the videos, which can be viewed for free on Youtube.com, Burgos shares what he’s learned from over three decades in the industry. Burgos’ website, www.flexoexchange.com, is an online community dedicated to the flexo industry. Here, a forum is provided for flexo industry professionals to buy and sell equipment, post job information, network,and discuss issues and trends.
Burgos credits the label industry with being an instrumental force in driving flexo technology. “Label converters have really done an amazing service to flexography. Operators of label presses have been willing to experiment and learn. A paradigm has been broken, pushing the technology to new frontiers,” Burgos says, citing platform and combination presses as examples.
Some label industry professionals, discussing how far flexo has come, compare flexo to offset, and note how closely the flexo printed product resembles offset. That’s certainly one way to look at it. Another way is to now think of flexo as it’s own entity.
Mac Rosenbaum of Aquaflex feels the advances in flexo have changed the way it’s perceived. He says, “Flexo print quality no longer rivals offset print quality. Today, flexo has carved out its own turf in the package and label printing industries – cost effective, high quality inline printing and converting for everything from short-runs to high-speed long runs on paper, film or board. It is perhaps the most versatile printing process in the world and the process is perfectly aligned with the future of a dynamic packaging industry. As the flexo process becomes more and more automated, it becomes more and more a manufacturing process capable of zero defect product for less cost. It isn’t what the future holds for flexo, it’s what flexo holds for the future.”
And now a word from the economy
The current state of the economy is on everyone’s mind, and label industry leaders are no exception. With that said, a discussion about flexo trends is also going to be one that touches on the impact the downturn has taken. For flexo, however, there’s a silver lining, as today’s trends of automation and efficiency are effective tools in achieving profitability, which is why converters are in business.
“With the economy in turmoil, the goal now is profitability, and the means to profitability is process efficiency,” says David Lanska of Stork. “Getting the presses up and running faster reduces raw material and energy consumption, reduces the waste stream, and improves press utilization. Of course, a press isn’t making money when it is producing scrap at 500 fpm. By verifying that quality parameters are met, printers have less internal rejected material and fewer returned goods.”
Jeff Feltz of Mark Andy says, “Converters are under significant pressures these days – rising material costs, shorter runs, a diminishing pool of qualified operators, commoditized business, and shrinking margins. New flexographic presses are providing ways to combat these pressures. Servo driven presses are enabling converters to change over more quickly while eliminating thousands of dollars in waste,” he says.
Nilpeter’s Andy Colletta agrees. “In these difficult times where everyone is scrambling keep their heads above water, one of the dramatic aspects of today’s flexo press is the ability to reduce makeready time as well as material waste, to minimal amounts.” He adds that the expectations are for continued improvement in the design of servo driven flexo presses, which will only further enhance the ROI for the label printer.