Flexo Plates: High-Definition Flexo for Cost-Effective Print Production
The industry is awash with talk of high-definition flexo – new solutions that are designed to improve image-highlight reproduction, increase printed line screen capabilities and deliver gravure-like print quality – key aspects in the delivery of “packaging that sells.”
And while there is no doubt that brands care deeply about shelf impact, many would agree that more often, conversations today with brand managers revolve around turnaround times and total cost of production rather than around print quality. Excellent print quality is simply expected and improvements are always welcomed, but they very rarely command a price.
The truth is that the introduction of the right high-definition flexo plate into print production can have a profound effect on production efficiency, cost reduction and quality regardless of printed line screen or graphic design. Flexible packaging printers that have introduced these plates into production are claiming a reduction in make-ready time and materials, improvements in press run speeds, plates that last longer and a downturn in the number of spot color inks used.
Let’s examine a checklist of three key high-definition attributes that will deliver the greatest efficiency benefits in mainstream production.
Three key attributes1. A flat top dot – one that is created in the absence of oxygen – with strong shoulders and a wide base is a key factor for print stability. Dots across the entire tonal range must be the same height. This provides a solid foundation for even impression across the web, highlight dots that resist wear and dot surfaces that are ready for the application of surface texturing to improve ink transfer efficiency.
2. The second attribute is imaging resolution and image fidelity. True stability, consistency and predictability on press come from knowing exactly what will be on a printing plate. There is no room for unpredictable dot growth or shrinkage compared to what was in the original file – it needs to be the same every single time, pixel for pixel – so look for a solution that gives you true 1:1 reproduction from file to plate. The factors that affect this are laser imaging technology, the material that is being imaged (for example, a carbon layer or a high-resolution dye-based material), and the process being used to form the dot (once again, you want an oxygen-free environment for plate exposure).
3. Efficient ink transfer is possibly the single most important element in driving press efficiency benefits for wide web flexo printing, especially on film substrates. The key is to get an even ink film laid down that eliminates voids, gives great optical density and clean printed colors but uses less ink volume, and removes the need for over-impressing to maintain density. A high-definition flexo plate system can apply a micro-fine surface pattern to the plate surface to improve the flow of ink to the substrate. When experimenting in this area at Kodak, we determined that two factors were critical for consistently efficient ink transfer: the use of a flat top dot structure, and the size of the element that forms the micro pattern – a consistent 5x10 micron element drove the biggest benefit.
Spot the big benefitsWith optimization complete, the possibilities become endless and the returns significant. In addition to the line speed, make-ready and plate longevity benefits discussed previously, a high-definition, stable, consistent print platform – with a wider color gamut by the way – opens the door for other benefits.