摘要 |
The invention relates to a value document, especially a banknote, having a sequence of layers into which visually and/or mechanically perceptible identifiers in the form of patterns, letters, numbers or images are introduced by the action of laser radiation. According to the present invention, the sequence of layers includes a marking layer (22) composed of an ink mixture (24, 26) exhibiting a laser-radiation-absorbing mixture component (26) and a laser-radiation-transparent mixture component (24), the identifiers being visually and/or mechanically perceptible due to an irreversible change in the optical properties of the ink mixture (24, 26), effected by the action of the laser radiation. |