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FLEXO® Magazine | Feature ArticleThis article appeared in the October, 2006 IssueCTP: No Longer "If," But "When"Technology Helps Flexo Close Quality Gap with Offset & GravureBy Ray BodwellThe value of computer-to-plate (CTP) for flexo has been a hotly debated topic throughout the North American packaging value chain for the last ten years. Although the high quality and improved performance of digital plates on press was apparent right from the start, the early CTP workflow was viewed as complicated and slow. On top of that, the equipment and plates associated with a fully digital workflow were clearly more expensive than their analog counterparts. As a result, flexographers were reluctant to adopt this new technology.As the technology improved, the process became fasterand simpler and equipment became more affordable.Flexographers and their customers started to recognizesome of the benefits of digital plates, and thediscussion within the industry broadened. Althoughcost and workflow were still concerns, the industrynow began to debate the "fit" for CTP. Where did thistechnology belong? Who could justify the investment?Where would skilled operators come from? Did allsegments need digital quality? Which jobs wereworthy of digital quality?Today, the digital workflow for flexo has matured, andthe output, workflow and plate technologies associated with CTP are faster, better and cheaper. If you review the prevailing industry trends, it appears that the question flexographers are now asking themselves is not "if" they should convert to CTP, but "when."Number of InstallationsNumbers tell the story, and whether you're looking at hardware or consumables, the trends are undeniable. Currently, there are in excess of 400 flexo CTP engines installed in North America. Ranging in size from as small as 20 in. x 21 in. to as large as 50 in. x 80 in., they are producing a growing share of the plates in the tag and label, flexible packaging and folding carton segments. According to Mark Vanover, director of marketing, Esko Graphics, "We've already installed more than 300 digital flexo CTP systems in North America, with no sign of a slowdown in demand. We continue to see strong growth in the narrow-web tag and label markets along with the wide-web flexible packaging markets."Plate sales also show a continuing swing to CTP, and digital plate manufacturers report strong growth in that area. "Our mix of plate sales continues to shift to digital," stated Dave Rashley, sales operations manager for DuPont. "Today, well over 50 percent of our plate sales are digital, and, if anything, theconversion from analog to digital is accelerating. This trend is equally true for both our solvent and thermal product families."Imaging versus EngravingIt's not "one size fits all" when it comes to digital, and there are actually two completely different versions of CTP in use in flexo today. Laser-engraving systems utilize high-powered lasers to remove non-image areas from either a flat or in-the-round rubber or polymeric plate material. This is the original flexo CTP workflow, and laser engravers still have a prominent position in the tissue and towel market where large, continuous-print cylinders are required. Smaller format systems have been introduced in recent years, but concerns about productivity and quality have prevented engraving from achieving broad market acceptance.The most widely accepted flexo CTP technology islaser imaging. In the laser "platesetter," alower-powered laser is used to ablate (image) aphotographic mask that has been applied to the surfaceof the plate by the plate manufacturer. Once the masklayer-sometimes referred to as "LAMs" or "laserablation mask"-has been imaged, the plate is UVexposed and processed in the same manner as with ananalog photopolymer plate, with the exception that novacuum needs to be drawn during the plate exposurestep. The advantage to this approach is that users gainall the quality and productivity improvementsassociated with a digital workflow while maintainingthe ability to process either analog or digital plates intheir existing platemaking equipment.Early AdoptersThe pioneers of CTP were the flexo prepress trade shops. Already a key element in the packaging value chain, they quickly realized that an investment in CTP would help them maintain their position as a vital link between CPCs (consumer product companies) and printer-converters. They were able to impress brand managers with the improved image quality that came from digital while demonstrating the advantages of digital productivity and consistency to the printers. Their early support of CTP led to improvements in flexo productivity and helped close the quality gap between flexo and offset and gravure.Today, CTP is in near universal use throughout the prepress segment, with many providers producing the majority of their plates digitally. "Over 95 percent of our plates are now digital," noted Pete Lehman, vice president of Southern Graphic Systems in Philadelphia, PA. "Not only do our customers find that digital plates print better and more predictably, but we discovered early on that a fully digital workflow-including CTP- is actually more efficient for us as a prepress provider. We eliminate the variables of an analog workflow and produce a much more consistent product with minimal makeover."Many of the larger flexible packaging printers that havein-house analog platemaking capabilities have begun tobring CTP inside as well. Their trade shop still providesthese printers with all the necessary prepress services andbackup platemaking, but now-rather than waiting for anegative via courier-they receive a digital file, ready forimaging as soon as the client approves it. Not only doesthis take the cost and time of shipping films out of theequation, but digital connectivity also allows these printersto be more responsive to last-minute design changes orcorrections.Because tag and label printers frequently compete againsthigh-quality offset, they were quick to recognize the qualityadvantages of digital, but had to wait until appropriatelysized and priced CTP units were available. Oncesmall-format CTP units became available, however, theprime label printers jumped on the CTP bandwagon and never looked back. According to Peter Spain, marketing manager for Pitman Co., "Pitman is very focused on tag and label printers, and we've been amazed by how quickly this segment has adopted CTP. We've placed over 125 units since 2002 and see no signs of a slowdown."Why Hasn't Everyone Converted?Not all segments or niches have fully embraced CTP. Smaller tag and label printers, flexible packaging printers with large analog film archives, and corrugated prepress providers have taken a "wait and see" position, but here, too, change is underway.The continued reduction in both size and price of CTPengines has finally given even the smallest tag and labelprinter the opportunity to seriously consider moving fromanalog to digital platemaking. Small units that include allthe necessary workflow software are now available, andlabel printers making as few as four or five sets of platesper day can justify an investment in CTP. They, too, arefinding that digital quality makes them more competitive,and the move to CTP allows them to shut down their agingimagesetters and film processors.For flexible packaging printers with a large archive of filefilms, the transition to digital can be a lengthy process.Some find themselves running many of the same packagedesigns for years, simply remaking analog plates fromexisting film negatives when needed and only converting todigital when the package design is changed. A number ofprinters, however, have determined that digital plates are their preferred image carrier and haveaccelerated the conversion to digital, either by reworking the design files or scanning their archived films so that they can apply the required digital reproduction curves. The cost of this conversion is often shared by the participants, and the industry has developed some creative solutions to accelerate the transition from analog to digital. "Our plate supplier put together a conversion program to help us offset the cost of converting from an analog to a digital workflow," noted Lin Jackson, corporate graphic service manager for Pliant Corp. "It made the transition cost-effective and helped us to more quickly move to a fully digital workflow."Even the corrugated market-long recognized as one ofpackaging's most price-sensitive sectors-is beginningto look to CTP. Farsighted corrugated prepressproviders are investing in platesetters and looking atways to utilize the efficiency and productivity of afully digital workflow to enhance their value in anincreasingly competitive market. Plate and equipmentmanufacturers are working closely with these leadersto define workflows that will increase productivity andreduce total delivered cost while improving overallquality.What About ITR?Continuous print sleeves that are imaged in-the-roundhave long been considered the ultimate image carrierfor flexo. Quick press changeover, high press speeds,long run length and high resolution are compelling drivers, and the strong growth of flexo ITR in Europe seems to support those claims. In particular, ITR's improved registration accuracy has allowed European flexographers to meet and often exceed the quality of gravure. Since nearly half of all flexible packaging in Western Europe is still printed gravure, ITR has allowed flexographers there to grow their markets at the expense of their not-in-kind competitors.In North America, on the other hand, flexo has already become the printing process of choice in flexible packaging. Here, the focus on low cost and fast turnaround, coupled with frequent design changes and shorter press runs, has limited the market acceptance and ITR; although, there has been growth in select niches. In addition to the laser-engraved cylinders used in the tissue and towel market that was mentioned earlier, high-resolution photopolymer ITR has begun to appear in confectionery, snack foods and other markets where tightly nested images or long run lengths are common. Despite these market entries, however, the majority of North American flexographers have determined that, for now at least, CTP imaging of traditional flat photopolymer plates gives them the benefits they are looking for.Conclusion: No Longer OptionalEarlier in this article, it was mentioned that cost-especially higher plate cost-was one of the early concerns with digital. In the not too distant future, this situation will likely reverse itself, and the costs associated with an analog workflow will actually be higher than digital. With the rapid conversion to CTP that is underway or already completed throughout the printing industry, the usage of graphic artsfilm has sharply declined. Film manufacturers are beginning to reduce capacity and raise prices as the global demand for film decreases. Two of the premier manufacturers of film output devices-Esko Graphics and Agfa-have discontinued or announced plans to discontinue the manufacturing of imagesetters. Film processors are also more difficult to find and expensive to maintain and have the ever increasing environmental concerns associated withfilm and chemistry disposal.There is also the factor of digital "momentum." CTP nowoccupies such a strong position and mindshare inpackaging that the tipping point has been reached. Designand prepress today are fully digital. With the maturation ofdigital color management, proofing and computer-to-plate,job files will be prepared under the assumption that theywill be output digitally. These outputs could take a varietyof forms; including, but certainly not limited to, a flexoplate. This ability to digitally "repurpose" files for a varietyof media has prompted many prepress providers to expandtheir scope of operation and define their services in termssuch as premedia, database management, and imagingsolutions, not just platemakers.With the large number of flexo CTP units already installedin North America, it's obvious that many innovators andindustry leaders have already made the move to digital. Although they may occasionally discuss the challenges they had to overcome to go digital, you'll never hear them say that they wish they hadn't done it. They have realized the economic, productive and quality benefits of moving to CTP, while demonstrating industry leadership and gaining competitive advantage.If your company has not yet invested in CTP, don't panic. There is still plenty of time to put together a technology team that will research the options and define the best CTP path for your business. But it is time to act. If you are a flexographer expecting to maintain your position or grow your business, the decision in front of your company is no longer "if" you should invest in CTP, but "when." An analog workflow may have served you in the past, but it won't take you into the future. Like the phonograph record, it's about to become a relic from a bygone era.ABOUT THE AUTHOR: Ray Bodwell is the North American marketing manager for the packaging graphics business of DuPont Imaging Technologies.Copyright ©1996-2009 Flexographic Technical Association. All rights reserved.CTP:不再“如果”,而是“何时”科技助柔性版缩小与平版胶印与凹印之间的差距罗伊•勃得威尔最近十年, CTP在柔印中的价值在北美洲包装的产业链中成为了一个热烈辩论的话题。