Clearmagnetic intaglio printing ink

Abstract

The invention discloses an ink for the engraved steel die printing process, having a viscosity at 40°C between 3 Pa.s to 15 Pa.s, preferably 5 to 10 Pa.s, and comprising a polymeric organic binder and magnetic pigment particle, characterized in that said magnetic pigment particles comprises a magnetic core material which is surrounded by at least one layer o f another material. The surrounding layers, single or in combination, confer the pigment particle particular optical properties in the visible and / or in the near IR, chosen from high specular or diffuse reflectance, spectrally selective absorption or reflection, and angle-dependent absorption or reflection, and allow for the formulation of inks having a large gamut o f color and other optical functionalities.