Patent ID: 7141523
Filing Date: 2006-11-28
Classification: B29K,C03B,C03C,C04B,G02B

Abstract:
1. Glass collectively comprising at least 80 percent by weight of (i) at least one of Nb 2 O 5 or Ta 2 O 5 ,(ii) at least one of ZrO 2 or HfO 2 , and (iii) at least one of Al 2 O 3 or REO, and the glass containing not more than 20 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 , with the proviso that the glass does not comprise 35.73 percent by weight Al 2 O 3 , 42.17 percent by weight La 2 O 3 , 17.1 percent by weight ZrO 2 , and 5 percent by weight of one of Nb 2 O 5 or Ta 2 O 5 , based on the total weight of the glass.