Measurement field for determining the smearing limit during printing

Abstract

A measurement field allows determining the smearing limit during printing, in particular during lithographic wet offset printing. The measurement field is arranged on a printing form, in particular a printing plate, which has printing, ink-carrying regions and nonprinting, dampening solution-carrying regions on its surface. A dampening solution-carrying property in the region of the measurement field is reduced by a nanoscopic coating (e.g., with amphiphilic molecules) or an unscreened, microscopic coating (e.g., a polymer coating) in comparison with the dampening solution-carrying property in the nonprinting regions of the surface of the printing form. The nanoscopic coating or the microscopic coating advantageously leads to a shifting of the smearing limit, that is to say to a displacement of the starting point of scumming, by the dampening solution requirement which is increased for scum-free printing within the region of the measurement field. Such a measurement field is thus advantageously used for the closed-loop control of a dampening solution supply.

Dependencies are inferred from the claim text.