US Patent 7193355 Reflection layers formed from an aluminum oxide particle mixture

An aluminum oxide particle mixture for reflection layers in discharge lamps, and to discharge lamps of this type. The mixture has a first coarse-grained component and a second fine-grained component, with a primary grain size of preferably d50(1) between 0.3 μm and 0.5 μm and d50(2) of at most 0.05 μm, respectively (with an agglomerated size of the fine particles of less than 0.15 μm).