Method for producing optical effect layers comprising magnetic or magnetizable pigment particles and exhibiting one or more indicia

Abstract

The invention relates to the field of the protection of security documents such as for example banknotes and identity documents against counterfeit and illegal reproduction. In particular, the present invention provides methods for producing optical effect layers (OELs) exhibiting one or more indicia (x30) on a substrate (x20), said method comprising a step of exposing a coating layer (x10) comprising non-spherical magnetic or magnetizable pigment particles to a magnetic field of a magnetic-field generating device so as to orient at least a part of the magnetic or magnetizable pigment particles; a step of applying a top coating composition on top of the coating layer (x10) and in the form of one or more indicia (x30), and a step of at least partially curing the coating layer (x10) and the one or more indicia (x30) with a curing unit (x50).