Flexographic Printers: How to Select the Right Mounting Tapes

“Mounting tapes, the unsung heroes of the flexographic printing process, can make or break the quality of a print job. Careful selection of plates and cylinders, while immensely important to the final product, can be negated if the chosen mounting tape does not meet the requirements of the print job.

With so many tape choices available, spanning the spectrum of soft to hard and with several combinations of adhesives, selecting the right mounting tape may appear to be a daunting task, but some reference points and a little bit of experimentation can help guide the process”¹.

The Density Issue

“Typically, the most pressing issue in selecting a mounting tape is determining how hard or dense the tape should be. Many mounting tape suppliers offer a range of hardnesses that can include variations such as very soft, medium-soft, medium, medium-hard, hard, and more”¹.

“According to Joe Prunier, marketing manager for print and web processing at tesa tape, harder tapes are generally best when printing solids, and softer tapes are better when printing high-resolution screens or process work. This is because images created for four-color separations are really arrays of very tiny dots that must be placed accurately onto the substrate to achieve the desired color. Too hard a tape creates resistance on the plate and the dots will be larger than they should be, creating color shifts in the final product”¹.

“If there’s too much resistance and you squeeze that dot too much, it makes it bigger than it should be, which creates dot gain,” Prunier explains. “Dot gain completely changes the color characteristic. A color can come in too vivid or be too dark¹”.

“Yet on the other hand, when printing a solid color or an opaque white, a harder tape is needed because the coverage needs to be as dense as possible, and the resistance increases the color density. Scott Johnston, a corporate account manager at Anderson & Vreeland, explains that as press speeds are increasing, so is the usage of harder tapes”^1.

 ^{“Generally, harder plate materials these days mean faster presses and we’re recommending firmer plate mount tapes 1.”}            

1.Reference: Cory Francer, 2015, “Best Practices: Managing Mounting Tapes” retrieved at
https://www.packageprinting.com/article/best-practices-managing-mounting-tapes-2/