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Advances in Flexography



From mechanical to electronic and digital, flexo redefines its boundaries.



By Jack Kenny



Published July 20, 2005
Related Searches: Lean Manufacturing Cold foil Hot foil Flexography
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Flexography's march from a rudimentary form of printing to its current state of advanced capability has been steady over several decades. Flexo reached its prime, in a sense, in the 1990s when flexographers demonstrated that they could, indeed, print and convert products to rival those made on offset and gravure presses.

The gradual but inevitable acceptance of UV curable inks strengthened flexography even more, moving the process to higher levels of quality. Advancements in anilox rolls, printing plates, in-line inspection equipment, web guides, dies and tooling, adhesives, and substrates — a wealth of innovative substrates — have combined to lift flexography to a lofty level of sophistication.

A closer look at the past couple of years, however, gives new meaning to the term sophistication as it applies to flexography. After a period of courtship, far-sighted flexographers now find themselves engaged with printing machines that combine familiar mechanics with new (to them) electronics and digital technology.

Flexo now ranges from the simple to the mind-boggling. Printers, those already at the high end and those seeking to join them, are driving the change. Press manufacturers are driving the change. OEM companies are driving the change. And those who order the labels, a breed of intelligent print buyers, are driving the change.

"The industry is going through a generational transition. The pioneers got into this business 20-plus years ago, and through guts and perseverance, through trial and error they have become very successful people. A lot of the equipment placed in the first 15 years of flexo's upward curve — starting in the mid-1980s through the 1990s — that equipment served its purpose then," says Roy Webb, national sales manager for Mark Andy, St. Louis, MO, USA.

"Now the industry is more sophisticated. As a result of that sophistication, within the industry and in the customer base, the needs of the converters had to get better. Pressure has been applied back down to manufacturers such as ourselves," Webb says. "We had to look at the industry and ask how better to improve the magic box we have produced for the past 20 years. The old technology is no longer capable, in some cases, to do tight registration work; it is limited in its capability to handle certain materials, to accomplish the specialty converting work that's out there today.

"So the press manufacturers are seeing the opportunity to have a lot of that older equipment upgraded, turned over, turned in. We have realized through trial and error with our customers that more is needed to satisfy the segments of this market — the wide variety of colors; the films, metalized substrates, laminations; the different adhesives, the complex applications such as lottery tickets and RFID. The industry is going through a big change to satisfy this base."

Press changes, according to Webb, derive from basic converter needs: They must be easy to set up and easy to break down; they must be capable of running a wider range of materials; and they must be able to run multiple processes — water based inks, UV curable inks and coatings, hot foil stamping, cold foil stamping, screen printing. The list goes on.

"Converters are running at higher speeds," Webb notes. "Those that are running water based inks and serving that market segment are asking for greater press speed, so drying has become an issue from a manufacturer's design perspective — rapid speeds and maintaining quality and register. The key for the converter is setting up quickly, running quickly, getting the job off the press quickly, and setting up the next job as rapidly as possible. The frequency of orders is higher, the quantities are smaller, and demand for quality continues to get higher."

The S word
"The biggest buzz is servo. Everyone hears it. We get more inquiries every day: What is it? How does it work?"

Terry Trexler is the product manager for Gallus Inc., the Philadelphia based arm of the Swiss narrow web press manufacturer Gallus Ferd. Rüesch. A few years back, Gallus introduced its RCS 330, a fully servo driven press now in use at several European label companies and two in the US.

"What people are led to believe is that a servo driven press means quicker makeready, improved registration accuracy, ability to use a wider range of substrates, a better solution to the snap-back issue, the ability to speed up and slow down the impression cylinders. These are all good conceptions, and they are all true.

"The servo press will offer faster makeready because it lends itself to sleeve technology. With servo drives repeat jobs are basically plugged into the computer of the press, and can be recalled with press tension settings, heat management tool settings, chill roll settings, lamp intensities, speeds, all on the computer."

Servos are electronic motors, linked to a central brain, that connect directly to moving parts of the press and replace shafts and gears. Servo technology is not new; wide web presses have employed them for years. They began showing up on narrow web presses several years ago, and gradually have been incorporated into the designs of new machines from virtually all of the press manufacturers in the label industry. They bump up the cost of a press, and for narrow web printers that increase is noticeable. Moreover, their presence on a press demands new skills.

"A totally electronic servo driven press reduces setup times, reduces waste on the press, and allows the printer to get better quality off the end of the press," says Andy Gillis, sales engineer for Paper Converting Machine Co. (PCMC), in Green Bay, WI. The company manufactures wide web converting presses for use in several industries, but also makes narrow Webtron presses. Its new Evolution is a 26" wide servo driven machine.

"One servo driven Evolution will do the work of two or three 18" gear presses," Gillis says. "You get more throughput from one press to streamline production."

The electronics inherent in a servo driven flexo press is changing the culture in the printing plant. "An electronic press with a digital operator interface means that the press remembers every job," Gillis says. "Each run has a job recipe, and you can call up a job at any time from the recipe storage. It contains all the details, just like on your desktop computer: impression settings, ink meter settings. With fiber optic cables, Ethernet and 32-bit architecture, the press communicates a lot faster. And it's immune to electrical noise."

Gillis and others point out that such innovations require a different type of operator. "It can be scary," he says. "Wide web operators have a different skill set — a lot of them have press maintenance staffs. In narrow web the operator is the maintenance guy doing the troubleshooting. As a press manufacturer, we had to come up with a training package to ease that fear."

"If you don't put the right person on the machine it can actually backfire on you," states Mac Rosenbaum, vice president of marketing for Aquaflex, a division of F.L. Smithe Machine Co. in Duncansville, PA. Aquaflex is rolling out a new FPC press, in which all gears and shafts have been replaced by servo motors.

"If you don't put somebody on that press who understands the electronic operator interface side as much as they do the mechanical side, you're paying for technology that you're not really using. They'll continue to make their change mechanically."

Federico d'Annunzio has a different view about flexo press operators and their roles in the future. D'Annunzio is one of two managing directors of GiDue, a press manufacturer in Turate, Italy.

"When improvements in prepress and plates are completed, the operator will be less trained and less skilled. You will need fewer trained operators, because the press will make the job and the operator is just a producer. With all the help that servos offer, the operators will be much more skilled in productivity. This industry leans toward operators who are not expensive. With a long training curve you run the risk of having higher costs than are needed."

D'Annunzio emphasizes that servo drives on a press don't improve quality. "The servo takes away the problems of the gears," he says. " It takes away the problems of service afterwards. It gives flexibility in the configuration of the press because you can add features later on. But in terms of printing it doesn't change the quality. If it's a good press, it doesn't need servos to perform."

Opinions differ about the need for a "fully" servo driven press. Gallus, PCMC and Aquaflex are marketing machines they describe as such. Others say that servo motors on every moving part are not required.

"A servo drive is not critical for every component of a press," says Mary Sullivan, global marketing manager for Mark Andy. "On our new XP 5000 press each print cylinder is driven by a servo motor. We also have it on die stations, and on unwinds and rewinds."

Jakob Landberg, sales director for Nilpeter, says that about 60 percent of presses built by the Danish company have servo drives. "It's a long way down the road to entirely servo, because you will need so many of them on each press. The trend today is to drive the print cylinder by direct servo. the transport of material through the machine is done by one combined servo with gears and shafts for each print station. In the future we will see one, two, a maximum of three servos for each print station. Not nine. It's too expensive."

Mark Andy's XP 5000

Sleeves and plates
Other forces have come into play recently to enhance the flexo experience. "During the past few years flexographic printing has developed deeply, thanks to new technologies introduced both in digital prepress systems and in printing with steady presses, in addition to servo drive technology," says Marco Calgagni, sales manager of Omet, a press manufacturer in Lecco, Italy.

"Digital prepress systems allow for the production of plates of very high quality," Calcagni adds. "There are also great developments in inks and anilox rolls. Press innovations have been reached principally through electronics, but of fundamental importance has been the cooperation among customers, suppliers and sub-suppliers. This has helped to focus attention on weak points and to definitively cancel them."

Landberg sees sleeve and other technologies growing in flexo's future. "Along with servos comes sleeve technology, which has taken the setup times down and the waste factor down. It's a big improvement. Presses now are being designed entirely for sleeves. They can be used for plates, for anilox rolls, for printing rolls. We have been able to handle that for some time, and we're seeing that sophisticated converters are thinking about it.

GiDue's X-Combat flexo press

"Web control has increased quite a lot over the past five to 10 years. Improved control of web tension gives tight register even on very sensitive materials."

"In terms of quality, a lot of work is being done to improve anilox technology," says d'Annunzio, "and also ink technology. Plates are improving, too, but they are still not as advanced as in the offset industry."

In the flexo plate manufacturing process, he says, "the manufacturing chain is still quite long. Offset has true computer-to-plate technology, but in flexo it's not quite there. This chain will probably shorten considerably: The technology is available, but will become more available at lower costs in the next five years. As soon as sleeve technology becomes more available, the whole plate industry will change. Plates that are not mounted but engraved directly on sleeves will have a big impact on quality.

Sleeve plates, he adds, offer improvements in several areas: "The first is register. The second is the cushion; adhesive cushion material will not have to be used any more, because several layers of cushioning material will be built into the sleeve. This will help to reduce or eliminate plate problems caused by vibration."

Landberg and d'Annunzio both single out the high cost of a flexo plate versus that of an offset plate. "If you shorten the development chain, you will reduce costs," says d'Annunzio. "I believe that the fight between flexo and offset will hinge upon the cost of the plate itself, the cost of processing."

So far the big changes in flexo are being pursued by a minority of converters. "The narrow web market is a bit slower to embrace higher technology," says PCMC's Gillis. "They're big on the status quo. When they find something that works, they stick with it. Change, for a lot of them, is scary. The straight PS converter is hurting because he has nothing to differentiate his product. Only a few narrow web companies are pursuing the new technologies actively."

"The bottom line is affordability," says Roy Webb of Mark Andy. "Companies with sales of $5 million or less are not in a position to entertain major equipment acquisitions. Those at $10 million or more are in a position to afford it, somewhat. And a lot of the owners with silver hair are riding out their last few days, looking for ways to make the transition, go to an ESOP, looking for buyers. They are not necessarily looking to put out a lot of money in the latter days of their careers.

"Probably less than 20 percent of the market is doing most of the new things that we talk about and read about," says Webb. "The other 80 percent do the rest, and probably with financial success."

A Gallus EM 280 flexo press at GS Inc., in Pascoag, RI, USA

Mac Rosenbaum at Aquaflex also sees reluctance to move forward, even when companies already possess higher-end technology. "People don't practice Lean Manufacturing and different philosophies enough. We see it on both sides of our business (F.L. Smithe makes envelope machinery), where the down times can be reduced drastically just by implementing cart change systems. You don't know how rare it is to see change-ready operators and machines.

"It goes much further than hanging the right tools on the machine; it's finding the weakest link in the plant and having other links in the plant come in and help when they're over capacity. A lot of time the problem is with the operator. Take the quality control slitter guy who might have some time, and for 10 minutes an hour have him help with the change-ready process. Reducing downtime by 30 percent in a month means hundreds of thousands of new labels.

"We supply a press, the InstaPrep, which was the first to have the quick change technology. It comes with a motorized cart that contains all the tools and tooling for a changeover. We have hundreds of them out there. It's rare that I see it used the way it was meant to be used. The motorized carts are not being employed. A few are, but more than half are not. They have all the technology there, but they don't use it. I think," Rosenbaum adds, "it's because the machine operator is in control of the plant.

"At the end of the day, if you're making money, why change? But at the end of the day also, those who sit back and make money are usually the ones who are left behind when the next cycle begins. It takes a forward looking management team, with the CEO, to make changes while you're making money. The few that do end up on the lists, like in Forbes magazine."



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