Substrates incorporating security devices

摘要

The invention comprises a security substrate comprising a fibrous substrate and a security device. The security device comprises an at least partially light transmissive polymeric carrier layer bearing a first security feature and the substrate being provided with a second security feature. The first and second security features are formed and located relative to each other such that, when one side of the security substrate is viewed in transmitted light the first and second security features visually combine to form a first composite image, which is not seen in reflected light.