Abstract: The present invention relates to the field of magnetic machine readable oxidative drying suitable for intaglio printing of security documents. In particular, the invention relates to magnetic oxidative drying ink for intaglio printing on a substrate, said magnetic oxidative drying ink having a viscosity in the range of about 3 to about 60 Pa s at 40° C. and 1000 s?1 and comprising a) at least one oxidative drying varnish, b) a plurality of core-shell pigment particles comprising a magnetic core and an external layer made of silver and c) one or more stabilizers selected from benzotriazole compounds.

Abstract: The present invention relates to the field of magnetic machine readable oxidative drying suitable for intaglio printing of security documents. In particular, the invention relates to magnetic oxidative drying ink for intaglio printing on a substrate, said magnetic oxidative drying ink having a viscosity in the range of about 3 to about 60 Pa s at 40° C. and 1000 s?1 and comprising a) at least one oxidative drying varnish, b) a plurality of core-shell pigment particles comprising a magnetic core and an external layer made of silver and c) one or more stabilizers selected from benzotriazole compounds.

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 having 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 of 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 of color and other optical functionalities.

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 of 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 of color and other optical functionalities.

Abstract: The invention discloses a reversibly piezochromic security element for the forgery-protection of value documents, the security element being characterized in that it comprises a collection of optically contrasting pigment particles in a film or a coating layer of an elastic polymer. In a particular embodiment, the particles are optically variable pigment flakes, oriented in a position which is substantially different from an alignment in the plane of the film or coating layer.