DATA CARRIER WITH MICROCONTOURS AND PRODUCTION METHOD

摘要

A data carrier has on its surface at least one marking (2) comprising a totality of individual elements (3), the optical properties of which differ from the optical properties of the surface of the carrier and which form a protective feature. The microcontours of the elements and/or their distribution on the area of the marking are/is unique for each marking, and at least one portion (3a) of said elements is arranged at a distance of at most 10 µm from one another and has linear dimensions in the range of 0.1-10 µm and/or linear dimensions (3b) in the range of 10-200 µm and an irregularity of the edge up to 20 µm, and/or (3c) an elongated form having a thickness of at most 50 µm. A reference element (4) can additionally be formed in the boundaries of the marking. A method for forming a protective marking on the surface of a data carrier consists in the fact that firstly a test object is produced, which comprises an arrangement of representations of groups of elements that differ with regard to their configuration, their optical density or their spatial frequency, with limit-value resolution and limit-value contrast for the selected method for application to the carrier material, and, subsequently, the test object is represented and the group is selected which comprises the elements which are distinguished by the parameters mentioned above and on the basis of which an original model of the marking is produced, said model being used during the process of applying the marking by the selected method.