abstract |
Security paper with narrow band luminescing authenticity characteristics which can only be excited in substantially the same wavelength region in which it also emits. With these authenticity characteristics therefore the authenticity signal is overlapped or covered by the test signal of several orders of magnitude stronger. The authenticity of the security papers cannot accordingly be tested with the normal processes or devices for determining of luminescence. The test devices used take advantage of the decay behavior of the luminescence emission for detection. The authenticity characteristics can be added to the paper material, the printing ink used, further mottling fibres or security threads. |