Security element, thermal transfer sheet, intermediate transfer recording medium, and method for formation of security element

摘要

The present invention provides a security element which is low in cost, is difficult to forge or alter, and can be applied to objects where a high level of security is required. The security element comprises at least a substrate and a fluorescent colorant layer provided on the substrate, wherein the fluorescent colorant layer comprises N species of fluorescent colorants Fn, wherein N is an integer of 2 or more and n is an integer of not less than one and not more than N, in the same layer, and the fluorescent colorant Fn absorbs light with a wavelength of lambda n and emits fluorescence with a wavelength of lambda n+1.