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 n and emits fluorescence with a wavelength of n+1.
