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(11) | EP 2 028 017 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Security devices for security substrates |
| (57) A security device (10) for security substrates, such as paper, used for making security
documents, such as bank notes, has anti-counterfeitable features. The security device
comprises a first opaque layer (14) and a second opaque layer (15), said opaque layers
each having a plurality of clear regions (18,19). A first fluorescent layer (16) is
positioned between the first and second opaque layers and a second fluorescent layer
(17) is positioned which is separated from the first fluorescent layer by one of the
opaque layers. The first and second fluorescent layers exhibit different visible colours
under ultraviolet light. The clear regions (18) in the first opaque layer form indicia
and the clear regions (19) in the second opaque layer overlap with only some of the
clear regions in the first opaque layer such that only a portion of the indicia are
visible in transmitted light.
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