Patent ID: 8591045

Claim:
Microspheres, comprising one of: (a) at least 45 wt-% TiO 2 ; at least about 0.5 wt-% and less than about 10 wt-% of one or more metal oxides selected from oxides of the lanthanide series elements; and between about 0.5 wt-% and about 25 wt-% of a combination of at least two alkaline earth oxides including selected from a group consisting of barium oxide, strontium oxide, and magnesium oxide; and (b) at least 45 wt-% TiO 2 ; at least about 0.5 wt-% and less than about 10 wt-% of one or more metal oxides selected from oxides of the lanthanide series elements; and between about 0.5 wt-% and about 30 wt-% of barium oxide; wherein the microspheres have a refractive index of at least 2.3.