1. A multilayer system ( 1 ), comprising a plurality of magnetic layers which are arranged one upon another and of which at least two layers are ferromagnetic and a ferromagnetic layer ( 2 ) has a large number of biased domains ( 5 ) with asymmetrical remagnetisation properties, the multilayer system being arranged on a substrate ( 6 ), wherein the substrate ( 6 ) is defined by at least one of the following: (a) the substrate ( 6 ) comprising a material selected from the group consisting of (i) a plastic selected from the group of polymers and (ii) paper; (b) the substrate ( 6 ) being curved; (c) the substrate being at least one element selected from the group consisting of a document and packaging; and wherein two of the ferromagnetic layers ( 2 ) are separated by a non-magnetic layer ( 7 ), wherein one of the two ferromagnetic layers ( 2 ) is adjacent to an antiferromagnetic layer ( 3 ), to which it is coupled by the exchange bias effect.