Anilox rolls are used as metering rolls in the flexographic printing process, delivering a precise quantity of ink to the plate roll (which contains the image to be printed). Anilox rolls are high precision parts with respect to their dimensional tolerances as well as to the engraved structures. The latter can nowadays be either very coarse in conjunction with a high volume of ink to be transferred or rather fine showing cell diameter of 20μm, cell walls below 3 μm in thickness and cell depth of only 6 μm and below. Moreover, the market needs for high quality printing will lead more and more to the outer limits of these ranges, which can be matched only by tailoring the coating properties, as well as the interaction of the laser radiation with the sprayed surface. Besides the needs for extreme screen counts in conjunction with requirements of certain volumes of liquid to be transferred, new types of surfaces are needed to meet these requirements and providing a wear resistant coating and concurrent an easy to clean surface. Therefore this paper will give a review of the interaction of the laser with a thermally sprayed surface focussing on the main laser parameters, different coating materials, the application of sealants as well as the type of engravings with respect to the achievable screen counts and transferrable ink volumes.
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