Abstract: A security element (2) for sticking onto a document (3) comprises a layer composite (1) of plastic material and has embedded, optically effective structures of a pattern (4). The optically effective structures in surface portions (13) of the pattern (4) are in a reference plane, defined by co-ordinate axis (x; y), of the layer composite (1) and are shaped into a reflecting interface. The interface is embedded between a transparent shaping layer and a protective layer of the layer composite (1). At least one surface portion (13) is of a dimension of greater than 0.4 mm and in the interface has at least one shaped macrostructure (M) which is an at least portion-wise steady and differentiatable function of the co-ordinates (x; y). The macrostructure (M) is curved at least in partial regions and is not a periodic triangular or rectangular function. In the surface portion (13) adjacent extreme values of the macrostructure (M) are at least 0.1 mm away from each other.