| 摘要 |
FIELD: chemistry.SUBSTANCE: inventions can be used for verification of authenticity and protection against counterfeit of valuable papers or documents, as well as high-quality goods. Security element contains luminescent substance of general formula BXO:Z, in which B is alkali earth metal, X is Nb and/or Ta, Z is luminescent activator, for instance, rare earth metal with oxidation degree +3, or Ti, or V, or Cr, or Cr, or Cr, or Cr, or Mn, or Mn, or Mn, or Mn. Atomic ratio B:X = 0.5:1 Main crystal lattice is additionally doped with one or several elements E, which act as luminescence sensitiser, and/or suppress certain emission wavelengths, and/or compensate charges. Luminiscent substance is obtained by mixing oxide, or hydroxide, or carbonate, or peroxide of element B, element X oxide and element Z oxide or carbonate. Mixture is annealed at 900-1200°C for 1-20 h. After that, product can be milled to desirable size of particles, which can be covered with protective coating, for instance of SiO. To verify security element authenticity of paper or valuable document, protected against counterfeit, said luminescent substance is excited, thereof-radiated light is registered, its properties are compared with the ones, known for said luminescent substance, with verifying authenticity in case of sufficient correspondence.EFFECT: increased verification efficiency.14 cl, 1 dwg, 8 ex |
