Material in film, particularly for security elements

Security element comprising a material as transparent film having a partially opaque coating with recesses, characterized in that the opaque coating is produced by a PVD or CVD process and comprises a single component material, as an element, a compound or an alloy, where the opaque coating, seen from different sides of the material in film form, shows a different optical appearance and has cavities in the form of signs, letters, drawings and / or lines, where the visual appearance different are It occurs through the defined regulation gradient oxidation of the element, compound or alloy, and appears opaque coating a metallic side and the other side appears colored or black form.