Patent ID: 9556058
Date: 2017-01-31
CPC Classifications: C03B,C03C,Y10T

Claim:
1. A glass comprising SiO 2 , Al 2 O 3 , and alkali oxides selected from the group consisting of Na 2 O and K 2 O, wherein SiO 2 +B 2 O 3 ≧66 mol %, 15 mol %≧Al 2 O 3 ≧7 mol %, B 2 O 3 ≦7 mol %, Na 2 O≧9 mol %, K 2 O≦2.37 mol %, B 2 O 3 + Na 2 O+K 2 O+MgO+CaO≧18 mol %, and CaO≦2 mol %, wherein 610.6 mol %−41.0[Al 2 O 3 ]+9.9[B 2 O 3 ]−3.5[Na 2 O]−20.2[K 2 O]−25.6[MgO]+34.2[CaO]≧0, where concentrations [Al 2 O 3 ], [B 2 O 3 ], [Na 2 O], [K 2 O], [MgO], and [CaO] are expressed in mol %.