DI(NITRATE) ACETYLACETONATOBIS (1,10-FENANTROLIN) LANTANOID (III) COMPOUND, SUITABLE FOR USE AS LUMINESCENT ADDITIVE TO INK, AND INK FOR HIDDEN MARKING VALUABLE OBJECTS Russian patent published in 2009 - IPC C07F5/00 

FIELD: chemistry.

SUBSTANCE: invention relates to new chemical compounds which belong to the class of mixed-ligand complexes of rare-earth elements, and specifically to a compound of di(nitrate)acetylacetonatobis(1,10-fenantrolin) lantanoid (III) of general formula [Ln(NO₃)₂Acac(Phen)₂]·H₂O, where lantanoid Ln is Tb_xEr_1-x, 0<x<1, Acac is an acetylacetonate ion, Phen is 1,10-fenantrolin, suitable for use as luminescent additive to ink for hidden marking valuable objects for counterfeit protection. Such an additive has three protective features, which are automatically controlled independently of each other. The first protective feature is ability to luminesce green light under UV-radiation. The second protective feature is ability to luminesce green light under effect of X-rays (X-ray luminescence). The third protective feature is thermo-luminescence, which is the ability to indefinitely store energy of UV- and X-ray radation and later emit green light upon heating.

EFFECT: possibility of univocal identification of a valuable object and increased protection efficiency.

2 cl, 2 ex, 4 tbl