A recent university study has confirmed what users of Screen’s 4,800 dpi Flexo Dot Hybrid Screening method already knew. Namely, that high-resolution screening delivers definite quality benefits in flexographic printing and Screen’s digital screening algorithms can improve flexo print results.

“With the higher resolution, you can image a smaller spot on the flexo plate,” observed Clemson University instructor Kern Cox, who led the study. “Flexo Dot adds small support elements around dots to get down to the smoother highlight transition and improve the quality of images.”

The Sonoco Institute of Packaging Design & Graphics at Clemson University set out to determine how well Flexo Dot stacks up against traditional 4,800 dpi and 2,400 dpi imaging resolutions. The study statistically verified that Flexo Dot “was the best performer for our test configuration” in terms of “smooth transitions in the highlight areas, increased quality in the shadows and drop shadows, and low dot gain value.”

Flexo Dot, a system of halftone dots designed for flexo and letterpress printing plates, creates extremely small, precise dots that are suitable for output at 4,800 dpi resolution. It is the screening method of choice in the fully automated EQUIOS Flexo Series workflow. Itself part of Screen’s turnkey Packaging Solution, EQUIOS Flexo Series automates job management in a packaging printing workflow from receipt of customer files through delivery of finished products.

Cox and his investigators focused on tonal reproduction and visual evaluation of highlights, looking closely at vignettes and tone scales because these elements are tied to image quality and smoothness of print. They ran test plates imaged on a Screen PlateRite FX series digital imaging device using the different screening methods under strictly defined parameters. Then the Clemson team measured the plates and the print.

“Flexo Dot allows the user to make a plate with very little adjustment to the curves — a large bump curve can give you a much larger tone value jump in the highlights,” Cox noted. “But the big benefit is the ability to get what I call the ‘turnkey solution.’ Put a system in, use the screening algorithms that exist and then produce good results, basically almost immediately.”

Screen USA is demonstrating EQUIOS Flexo Series workflow products, including Flexo Dot, at Labelexpo Americas 2012 in Booth #6347 from September 11-13 at the Donald E. Stephens Convention Center in Rosemont, Ill.