Patent ID: 10981406

Abstract:
A security feature for protecting valuable documents, in particular for ensuring the authenticity of valuable documents, comprises a luminescent pigment which has a host lattice doped with a first luminophore and a second luminophore, with an excitation energy of the first luminophore being transferable to the second luminophore. However, in the case of the luminescent pigment according to the invention, the excitation energy is not transferred completely from the first luminophore to the second, but rather only partially. The incomplete transfer of the excitation energy is achieved by selecting suitable amount-of-substance fractions of the first and the second luminophores on the luminescent pigment. As a result of the incomplete transfer of the excitation energy, the luminescent light that is emitted by the luminescent pigment also has, in addition to a luminescence peak of the second luminophore, a luminescence peak of the first luminophore.