Patent ID: 7598191

Claim:
A process for making a UV-absorbing glass, especially for a fluorescent lamp, said process comprising preparing a glass melt, said glass melt having a composition, in % by weight on an oxide basis of: SiO 2 60-75 B 2 O 3 >25-35 Al 2 O 3 0-10 Li 2 O 0-10 Na 2 O 0-20 K 2 O 0-20 MgO 0-8 CaO 0-20 SrO 0-5 BaO 0-5 ZnO 0-3 ZrO 2 0-5 TiO 2 0-10 Fe 2 O 3 0-0.5 CeO 2 0-0.5 MnO 2 0-1 Nd 2 O 3 0-1 WO 3 0-2 Bi 2 O 3 0-5 MoO 3 0-5 As 2 O 3 0-1 Sb 2 O 3 0-1 SO 4 2− 0-2 Cl −or 0-2 F − 0-2; wherein a sum total amount of Li 2 O+Na 2 O+K 2 O is 0 to 25% by weight; a sum total amount of MgO+CaO+SrO+BaO is 0 to 20% by weight; a sum total amount of Fe 2 O 3 +CeO 2 +TiO 2 +PbO+As 2 O 3 +Sb 2 O 3 is at least 0 to 10% by weight; and a sum total amount of PdO+PtO 3 +PtO 2 +PtO+RhO 2 +Rh 2 O 3 +IrO 2 +Ir 2 O 3 is from 0.00001-0.1% by weight.