Photomachinable glass compositions having tunable photosensitivity
The invention is directed to photomachinable glass compositions having a controllable or tunable photosensitivity, and to a method for making such compositions. The compositions of the invention contain titania (TiO 2 ) in an amount in the range of greater than 0.01 wt. % to 2 wt. % added to any known photomachinable glass composition. In one embodiment the TiO 2 in an amount in the range of greater than 0.01 wt. % to 1 wt. %. An example of a photomachinable glass of the invention is one having a composition having, in weight percent (wt. %) of 65-80% SiO 2 , 15-20% Li 2 O, 1-4% Na 2 O, 1-4% K 2 O, 2-10% Al 2 O 3 , 0-3% ZnO, 0-0.15% Sb 2 O 3 , 0-0.015% CeO 2 , 0-0.001% Au, 0-0.015% Ag and >0.01% to 2% TiO 2 , and the sum of Au+Ag is greater than zero. In particular embodiment the TiO 2 is in the range of >0.01% to 1%.
1. A photomachinable glass composition having a controllable or tunable photosensitivity, said glass comprising, in weight percent (wt. %), 65-80% SiO 2 , 15-20% Li 2 O, 1-4% Na 2 O, 1-4% K 2 O, 2-10% Al 2 O 3 , 0-3% ZnO, 0-0.15% Sb 2 O 3 , 0-0.015% CeO 2 , 0-0.001 Au, 0-0.015% Ag and >0.01% to 2% TiO 2 , and Ag+Au is greater than zero.
2. The photomachinable glass composition according to claim 1 , wherein the TiO 2 is in an amount in the range of >0.01% to 1%.
3. A photomachinable glass composition having a controllable or tunable photosensitivity, said glass comprising, in weight percent (wt. %), 70-80% SiO 2 , 15-20% Li 2 O, 1-2% Na 2 O, 2-4% K 2 O, 2-4% Al 2 O 3 , 0-2% ZnO, 0.05-0.15% Sb 2 O 3 , 0.005-0.015% CeO 2 , 0-0.001% Au, 0.05-0.015% Ag and >0.01% to 2% TiO 2 , and Ag+Au is greater than or equal to 0.05%.
4. The photomachinable glass composition according to claim 3 , wherein the TiO 2 is in the range of >0.01% to 1%.
5. A photomachinable glass composition having a controllable or tunable photosensitivity, said glass comprising, in weight percent (wt. %), 65-75% SiO 2 , 15-20% Li 2 O, 1-4% Na 2 O, 1-2% K 2 O, 5-10% Al 2 O 3 , 1-3% ZnO, 0-0.05% Sb 2 O 3 , 0-0.005% CeO 2 , 0-0.001% Au, 0-0.05% Ag and >0.01% to 2% TiO 2 , and Ag+Au is greater than zero.
6. The photomachinable glass composition according to claim 5 , wherein the TiO 2 is in the range of >0.01% to 1%.