Abstract: The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0.5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. The composition can be employed to form a luminescent film or layer within a plasma display panel.

Abstract: The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0.5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. One aspect the invention relates to a process for preparing the composition which comprises decomposing chelated metal luminescent compositions in solution at a relatively high pH while in the presence of dispersed core particles, thereby coating the core particles with hydrous metal oxides, recovering the coated particles, optionally washing the coated particles substantially free from soluble species, drying and calcining. In another aspect, a hydrous oxide coating is converted to a sulfide coating by treating the hydrous coating with a source of active sulfur.

Abstract: A dielectric ceramic powder composition for forming multilayer ceramic devices having thin dielectric layers with low porosity and having a dissipation factor which meets or exceeds X7R specifications, and consisting essentially of an admixture of a major component ceramic powder particle and minor component additives the amounts of which are controlled within certain predetermined ratios.