First introduced by Flint Group Flexographic Products at INFO*FLEX 2015 as “The Easy Way” to achieve flat top dots on flexo printing plates, nyloflex FTF Digital printing plates—with inherent flat top dots and a micro textured surface—continue to win the approval of printers and prepress providers worldwide.
One year later, the plate has been chosen as a winner of Flexographic Technical Association’s 2016 Technical Innovation Award in the Prepress Graphics category. “We are delighted to receive the 2016 FTA Technical Innovation Award,” commented Terri M. Stewart, director of marketing and inside sales at Flint Group Flexographic Products. “The award further confirms the outstanding response that we have received from the industry on the nyloflex FTF plate.”
Behind the Dot
Standing for Flat Top for Flexible Packaging, the FTF plate technology provides flat top dots on the plate by simply processing it like any standard round top plate—no additional investment, equipment, software, imaging upgrades, processing steps or consumable items are required. Due to the optimized texture of the plate’s surface that is imparted during manufacturing, there is no need to use digital surface screening in the file when imaging. This random surface texture, with its many and varied peaks and valleys, was carefully chosen to perform optimally in flexible package printing applications. This feature provides for an increase in solid ink density and more homogeneous ink laydown, even with standard imaging resolutions of 2,400 or 2,540 dpi.
To create an inherently flat top plate, the oxygen inhibiting effect must first be overcome through the use of internal photopolymer chemistry, rather than external sources, such as film lamination, nitrogen atmosphere or the application of high output UVA-LED light. This in itself is a remarkable challenge. But to formulate an inherently flat top plate and at the same time impart a texturized plate surface, the technical bar rises considerably.
Overcoming the effect of oxygen inhibition during open air exposure is not a challenge unique to digital flexo plate making, but rather any process utilizing free radical polymerization (e.g. dentistry). Options are limited in plate chemistry and manufacturing to not only provide a technical result, but to minimize cost introduced into the process. If this were a simple task, the industry would not have become so saturated in recent years with equipment and consumable techniques to overcome the oxygen effect and make flat top plates.
Manufacturing a plate that is inherently texturized has historically been difficult to attain without a considerable investment into production capabilities and knowhow. Through dedicated research and development activities, Flint Group’s team of R&D chemists was able to achieve several breakthrough discoveries, which allowed it to combine the features of a flat top plate with a micro textured surface to produce the most practical plate solution for the flexo printing industry—a technology which is of particular interest for packaging printers.
With the new functionality built into the nyloflex FTF Digital plate, flexible packaging printers will realize higher solid ink density and mottle free solids as compared to smooth plates, as well as the elimination of the trail edge void print defect. In today’s plate environment where flat top and surface screened plates are the status quo, these benefits are a must and no longer an option.
But printers will also find greatly improved plate surface texture consistency when sourcing nyloflex FTF plates from various locations, since it is not dependent on surface screening or the nuances of the various flat top systems in the market. By reducing the complexity of the plate making system and taking these pain points out of the picture, printers and prepress providers alike will be able to create more consistent plates from site to site, without the concern of slightly mismatched textures, which can have a surprisingly large effect on ink transfer. Moreover, plate maker printers or smaller prepress providers lacking the costly upgrades and equipment necessary to provide traditionally made flat top plates will now be able to enjoy the benefits they bring without any further investment.
In a nutshell, the nyloflex FTF plate puts the burden of creating these characteristics back into the plate manufacturing process, where it can most carefully and consistently be controlled.
Advances in “functional” or “intelligent” plate technology, which the nyloflex FTF Digital plate embodies, will likely push other technologies to strive in the direction of even faster press speeds and increased efficiency—e.g., inks will be modified to run more efficiently with these high ink carrying capacity surfaces. Cushioned tape and cushioned sleeve hardness/modulus options will be consolidated, as plates with higher functionality reduce the dependency on the tape to provide the desired solids and highlights.
High resolution imaging is likely the bottleneck of plate production, because of the slower speeds necessary to properly image such small patterns. While it is necessary for nearly all commercial surface screening, this is not the case for nyloflex FTF plates. Because its specialized texture is revealed at any resolution and is not dependent on a pattern in the plate file being imaged into the plate LAMS, production time can clearly be saved by imaging nyloflex FTF plates at lower resolutions. Actual field numbers from very large prepress providers that struggle frequently with this problem show a 33 percent increase in plate production when imaging at 2,400 or 2,540 dpi, compared to 4,000 dpi.
Proof of Technology
It is one thing to claim a plate, product or process is consistent. It is another thing to provide proof.
To support the claim that nyloflex FTF plates yield more consistent plates and print than traditional flat top plates with surface screening, a test was conducted where five market leading prepress providers provided a nyloflex FTF Digital plate without surface screening, as well as one traditional flat top plate with the latest and most successful surface screening technology. The 10 plates were mounted in the center of the same sleeve and then printed onto white polyethylene film with solvent based inks on a production flexible packaging press. The corresponding print samples were measured for printed dot area and solid ink density and compared.
As the graphs indicate, tonal value increase is much more consistent between the nyloflex FTF Digital plates as compared to the traditional flat top plates with surface screening (Figures 1a & 1b). With regard to measured densities, there is significantly more variation among the traditional flat top print samples, as compared to the very consistent SID measurements among the nyloflex FTF plate samples (Figures 2a & 2b). The greater variation between the traditional flat top print samples comes from the subtle differences in how the various flat top system technologies employed affect the plate, as well as slight variation in imaging devices, and the effect this has on rendering the same very small surface screening texture from imager to imager.
This variation is even more evident when visually examining solids from each print sample under magnification (Figure 3). As the images show, printed solids appear very consistent from one nyloflex FTF plate to the next; however, an examination of the traditional flat top plates shows varying levels of smoothness, the appearance of laser lines and occasional instances of trail edge void.
Poised for the Future
With the knowledge gained from this development for flexible packaging printing, one should expect that other application specific flat top plates from Flint Group Flexographic Products will soon be developed for corrugated, narrow web and folding carton segments of the industry as well. Because of the simplicity, convenience and economic advantages of the new technology, it is also likely that more complicated and expensive flat top technologies will soon fade away.
The future of flexo plates is clear—simpler for the plate maker while solving more problems for the printer. It is an exciting time to be a part of the industry.