TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The luminophore comprises a powdered alkaline earth metal silicate luminophore. A fluorine-functionalized organosilane of formula (Si(OR1)3X) (II) is used for fluorination of the alkaline earth metal silicate luminophore, where the formation of fluorinated protective layer on the silicate luminophore matrix is achieved by controlled hydrolysis and condensation, and the layer exhibits the barrier effect and hydrophobic properties. The silicate luminophore is of formula: ((Me1+Me2+Me3+)x1x (Si,P,B,V,N,C,Ge)y1x (O,N)z1:(A,F1,S1)) (VI); (Sr2-x2-y2-z2Cax2Bay2SiO5:Euz2,F1,S1) (IV); or (Sr3-x3-y3-z3Cax3Bay3SiO5:Euz3,F1,S1) (V). The alkaline earth ions are replaced optionally proportionately by additional divalent ions including magnesium, zinc or by appropriate measures including charge equalization by monovalent and/or trivalent cations of alkali metals or rare earth for optimizing the luminescence properties and the stability behavior and loads of the silicon of proportion phosphorus, boron, vanadium, nitrogen, germanium, and/or carbon can be incorporated into the anion lattice on the other side.R1 = CH3 or C2H5;X = F-functionalized organic ligand;A = activator including lanthanoid and/or manganese;F1 = surface fixed, optionally cross-linked fluorine, or fluorinated compound;S1 = optionally additional coating with non-fluorinated layer-forming materials;Me1+ = monovalent metal;Me2+ = divalent metal;Me3+ = trivalent metal of group III or lanthanoids, where Si is partially replaced by P, Al, B, V, N, Ge or C;x1 = greater than 0 and less than 5;y1 = greater than 0 and less than 12; andz1 = greater than 0 and less than 24;x2, y2 = 0-2;z2 = greater than 0 and less than 0.5;x3 = 0-0.05;y3 = 0-0.5; andz3 = greater than 0 and less than 0.25. EXAMPLE - Stoichiometric amounts of strontium carbonate, barium carbonate, calcium carbonate, europium oxide, silicon dioxide and ammonium chloride (0.2 mole) were mixed vigorously and then subjected to a 5-hour calcination process at 1400 degrees C in corundum crucibles under nitrogen or hydrogen atmosphere containing 20% hydrogen to synthesize the luminophore matrix. The calcinated material was homogenized, ground and washed with water after completing the calcination process. Subsequently the dried and screened luminophore (100 g) was introduced together with ammonium fluoride (1.1 g), glass beads (200 g) and water (1 l) into a suitable plastic vessel and mixed vigorously on a jar mill at low speed for 30 minutes. After a settling time of several minutes, the supernatant was first decanted and then filtered with suction through a Buchner funnel. This was followed by drying and screening to obtain the surface-modified silicate luminophore as an end product.