Correctly Calculate Flexographic Film Shrinkage to Improve Print Quality

The shrinkage is only related to the diameter of the plate cylinder (including double-sided tape and plate) and the thickness of the plate itself. Here is a formula used to calculate the shrinkage (percentage) of a film when it is used in a plane exposure to make a flexographic plate: Reduced volume (percent) = K/Rx100%.

In the formula, the coefficient K depends on the thickness of the plate used. At a thickness of 3.94 mm, K = 23.94 mm. R is the repeated circumference of the platen roller ((Rolling radius + plate thickness + pad plate + double-sided tape thickness) X2X3.1416] in millimeters. For example, if a certain roll has a repeated circumference of R=1248.6 mm (the roll radius is 191 mm, the plate thickness is 3.94 mm, the pad plate is 3 mm, the double-sided tape is 0.2 mm, K=23.94 mm)
The reduced edition volume = 23.94/1245.6x100% = 1.922%.

When designing an ink draft, the paper should be reduced in size according to the above ratio in the feed direction, and then plate-exposure the plate, so that the printed product will meet the dimensional requirements. Further explanation is that in the actual production, Due to changes in some people's causes and the environment, the calculated shrinkage will be different. Therefore, it is necessary for manufacturers to conduct on-site testing according to their own production conditions to ensure accuracy.