The press operator only wants the minimum necessary pressure to transfer ink from a printing plate to a substrate. The minimum impression or "kiss" impression between anilox-to-plate and plate-to-substrate is critical to successful flexographic printing. Slur is a blurred printed image, caused by impression settings and sometimes mechanical problems of the press. It is a printed defect characterized by the smearing of the trailing edges of a printed image or by the appearance of a double image. This can be caused by slippage of the substrate through the press which is caused by improper support of the sheet or other impression problems associated with anilox-to-plate or plate-to-substrate contact.
Too much impression between anilox-to-plate will result in a halftone dot that is hollow in the middle, like a doughnut. Too much plate-to-substrate impression will result in a dot that is solid in the middle with a soft vignette around the edge, resembling a halo.
