Abstract: Blue-emitting phosphors for use with plasma display panels (PDP) or other vacuum ultraviolet-excited (VUV) devices are provided. These blue-emitting phosphors and mixtures thereof include at least a europium-activated calcium-substituted barium hexa-aluminate (CBAL) phosphor. Preferably, the CBAL phosphor has a composition which may be represented by the formula: Ba1.29-x-yCaxEuyAl2O19.29, wherein 0<x<0.25 and 0.01<y<0.20. These blue-emitting phosphors exhibit improved degradation characteristics, including reduced color shift and increased intensity maintenance, under conditions found in VUV-excited devices.

Abstract: An electroluminescent phosphor powder includes copper-activated zinc sulfide particles that have a size distribution with a D50 value of no more than 10 ?m, where no more than 25% of the particles have a size greater than about 15 ?m and/or a 24-hr brightness of at least 15 footlamberts. These particles are made by a method that includes first firing copper-doped zinc sulfide mixed with zinc oxide, sulfur and a chloride-containing flux, rapidly cooling the mixture to below 100° C., and then mulling and second firing the mixture to provide a powder. The powder can then be elutriated to provide the electroluminescent powder with a narrow particle size distribution (more than 90% between about 5 and 15 ?m). The elutriating step can be avoided (albeit with a slightly wider size distribution) by more tightly controlling the first firing temperature.