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FLEXO Magazine : March 2013
standards in fact did not align, due primarily to the fact that the Phoenix Imperial substrate specified in ISO 2846 was too yellow compared to the actual production substrates used in flexo. This was reported to the ISO group and it was confirmed that other groups around the globe had found the same effect. At the same time, the supplier of the standard substrate, Scheufelin in Lenningen, Germany announced that it would cease production, due to the difficulty and cost of meeting the specification reproducibly. A less yellow theoretical target with no optical brightener was drafted some time ago. The draft substrate description vs. the existing spec is in Table 1 (page 22). Unfortunately, there has been insufficient sample of new substrate candidates to fully verify that it will actually achieve the intended result. Of course, there is also no commercial source for actual certifications either. Progress in establishing a revision to ISO 2846-5 has therefore been continually delayed. The various process ink values are reported in Table 4 below for reference. CONTINUING EVOLUTION Most certifications continue to be done on remaining stocks of the Scheufelin substrate until they are depleted. Some par- ties are requesting flexo inks to match the litho targets as in the ISO revision currently being pursued, but the actual spec still has the flexo target as different from the litho. It is only a matter of time until the specified substrate is entirely gone. At any rate, if the certifications are provided with actual test results, the inks are at least documented for future reference. And, as noted, certification to ISO 2846, is not of value to con- formance with ISO12647. Back to the FIRST/G7/ISO discussion: We won't address the value of the standard ink approach as in ISO vs. the standard print spec only as in FIRST. That would be a much longer report than this short update and plea for help. FTA/FIRST is the guideline from FTA for the flexo industry. While it does recommend the use of a standard ink, and gives color targets, it does not actually provide standard proofing measures and a standard substrate. It gives different targets for different ink chemistry platforms but does not distinguish for substrate. It is in revision now with Mark Mazur of DuPont and Robb Frimming of Schawk as chair and co-chair. G7 from IDEAlliance is similar to FIRST, but requires stan- dard inks, and does not establish final targets. It has been thrown open by IDEAlliance, and has been integrated into the latest ISO 12647-6. ISO has several standards relating to flexo process print- ing, which are listed in Table 2 (page 23). The names are pretty descriptive of what they do. This portion of the ISO standards is managed by Technical Committee 130 (TC 130). The U.S. arm of TC 130 is CGATS, administered by NPES. Steve Smiley of SmileyColor Associates and Danny Rich of Sun Chemical participate in both the CGATS and global TC 130 committees and are coordinating with the FQC. Of course, FTA regularly contributes input to CGATS and other standards bodies, with FTA input being gathered by the FQC Standards Working Group. NEXT STEPS For starters, we need to settle on a commercially available substrate for ink certification, and put that behind us. We need to settle on one that is "good enough." Somebody once said that resistance to change isn't the biggest barrier to progress, the desire for perfection is. The old spec and the new are in Table 1 (page 22). The lack of an approved substrate for certifications is an issue that needs resolution as soon as possible. If anyone or any organization has input about how we can source sub- strate under the new specs, please contact Duane Woolbright at FTA at firstname.lastname@example.org. Duane will coordi- nate with the FQC to get materials in the appropriate hands for validation testing. Secondly, the FQC ISO 2846-5 Project has been functionally tabled for the last couple of years. Work previously completed has demonstrated the invalidity of ISO 2846-5 for its intended purpose, and no future work can be completed until there is a substrate to work with. TC130 has been pursuing a revision, and when there is substrate available, a new project team will be started. The first step would be to check conformance of the old inks with the new specifications. If these do not conform, a project for new ink specs may be required. The target values in FIRST and the ISO2846 standards are compared in Table 4 (page 24). Finally, as the world continues to shrink, it would seem to be a great idea if FIRST supported and was consistent with the ISO standards. This does bring us back to the concept of pre- certifying inks on a single substrate. It is also the case that North America has the highest percentage of flexo printing, and a lot of sales are self-contained within the world regions. It makes sense to identify if we want our industry to have a barrier to foreign entry, or if it is more important to reduce barriers for U.S. international expansion. Ultimately, like everything else, it boils down to what an individual printer believes will work best for his business. Participation in the evolution of standards and FQC project supporting them is of individual, company, and industry value. Links to participate in the FQC projects, the FQC Standards Working Group, or the FIRST revision can be obtained on the FTA's website---www.flexography.org. About the Author: Paul Lodewyck led the Flexo Quality Consortium from 2005 through 2012. Over the years he proved an ardent supporter of technical research as a means of driving the industry forward and advancing scientific projects that foster understanding of the factors controlling the quality of the flexographic print- ing process. He has written numerous summary documents on FQC project activities, briefed progress regularly at FTA's Annual Forums and Fall Conferences, and driven integration of FQC efforts within the global standards community. In rec- ognition of that work, he received an FTA President's Award in 2011. Paul served Flint Group in a number of capacities in recent years, including, director project management, techni- cal director and vice president of technical services. www.flexography.org MARCH 2013 FLEXO 25