| abstract |
Crystallizable glasses, glass-ceramics, IXable glass-ceramics, and IX glass-ceramics are disclosed. The glass-ceramics exhibit β-spodumene ss as the predominant crystalline phase. These glasses and glass-ceramics, in mole %, include: 62-75 SiO 2 ; 10.5-17 Al 2 O 3 ; 5-13 Li 3 O; 0-4 ZnO; 0-8 MgO; 2-5 TiO 2 ; 0-4 B 2 O 3 ; 0-5 Na 2 O; 0-4 K 2 O; 0-2 ZrO 2 ; 0-7 P 2 O 5 ; 0-0.3 Fe 2 O 3 ; 0-2 MnOx; and 0.05-0.2 SnO 2 . Additionally, these glasses and glass-ceramics exhibit the following criteria:n a. a ratio: nn n n n n n [ n n n n n Li n 2 n n n O n n + n n n Na n 2 n n n O n n + n n n K n 2 n n n O n n + n MgO n + n ZnO n n _ n n ] n n n n n n n [ n n n n Al n 2 n n n n O n 3 n n n + n n n B n 2 n n n n O n 3 n n n n ] n n n n n n n n n between 0.7 to 1.5; n n n b. a ratio: n n n n n n n n n n [ n n n n TiO n 2 n n + n n SnO n 2 n n n _ n n ] n n n n n n n [ n n n SiO n 2 n n + n n n B n 2 n n n n O n 3 n n n n ] n n n n n n n n n greater than 0.04.n nFurthermore, the glass-ceramics exhibit an opacity ≧about 85% over the wavelength range of 400-700 nm for an about 0.8 mm thickness and colors an observer angle of 10° and a CIE illuminant F02 determined with specular reflectance included of a* between −3 and +3, b* between −6 and +6, and L* between 88 and 97. |