Patent ID: 7811496

Claim:
A method for making ceramic particles, the method comprising: providing first and second generally opposed surfaces; providing a mold comprising a plurality of at least one of particle openings or cavities; introducing a melt to at least a portion of the plurality of at least one of the particle openings or cavities of the mold, the melt comprising at least 35 percent by weight Al 2 O 3 , based on the total weight of the melt, and a first metal oxide other than Al 2 O 3 wherein the melt contains not more than 10 percent by weight collectively As 2 O 3 , B 2 O 3 , GeO 2 , P 2 O 5 , SiO 2 , TeO 2 , and V 2 O 5 , based on the total weight of the melt; passing the mold and the melt between the first and second generally opposed surface under pressure such that the melt in the at least one of the particle openings or cavities is under pressure; and at least partially cooling the melt in the at least one of the particle openings or cavities to provide ceramic particles comprising glass, the glass comprising at least 35 percent by weight Al 2 O 3 , based on the total weight of the glass, and a first metal oxide other than Al 2 O 3 , wherein the glass contains not more than 10 percent by weight collectively As 2 O 3 , B 2 O 3 , GeO 2 , P 2 O 5 , SiO 2 , TeO 2 , and V 2 O 5 , based on the total weight of the glass.