Measurement of the cell volume of Anilox rolls

The volume and shape of the cells in an anilox roll have a significant effect on the ink transferred to the flexographic plate. There is a need to accurately characterise the cells both immediately after manufacture for quality assurance purposes and during production to evaluate the effect of wear. As part of a study into ink transfer in the flexographic printing process, a new methodology for the characterisation of the cells in anilox rolls has been developed based on single cell analysis using white light interferometry. This allows for the inherent surface roughness caused by the manufacturing process. This method has been found to give accurate and repeatable results. This study also highlights key parameters that are necessary to define the cell characteristics. Comparisons have been made of measurements of the same anilox roll with other techniques including microscopy, volumetric and deformable tape. These offered advantages in terms of speed and cost, but generally at the expense of accuracy. However, they may be viable for use in monitoring wear.