FIELD: printing industry.
SUBSTANCE: invention relates to a data medium (10) equipped with a pattern (12), which is made by metallographic printing and when observed with an unaided eye is perceived as a half-tone image with smooth transition of tone gradations. The pattern (12) contains many thin relief printed lines that are not visible to the unaided eye and are continuously modulated along their width and/or height, and accordingly provide different tone gradations of the half-tone image.
EFFECT: increased extent of data medium protection against counterfeit due to provision of possibility to combine the specified pattern with tactile elements.
44 cl, 5 dwg
