Fast fading, high refractive index photochromic glass
US5023209A · kind A · utility
20Cited by
9References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1990 |
| Grant date | Jun 11, 1991 |
| Priority date | — |
| Expiry date | Sep 13, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S501/903
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This invention is directed to the preparation of silver halide-containing photochromic glasses exhibiting refractive indices between 1.585-1.610, Abbe numbers higher than 41, and densities less than 2.80 g/cm.sup.3 generally consisting essentially, in weight percent, of: ______________________________________ SiO.sub.2 43-52 SrO 0.8-9 B.sub.2 O.sub.3 12.5-18 BaO 1-9 Al.sub.2 O.sub.3 0-3 K.sub.2 O 2-9 ZrO.sub.2 3-8 TiO.sub.2 2-8 Li.sub.2 O 1.5-3.5 Ag 0.100-0.175 Na.sub.2 O 0.3-3 Cl 0.140-0.350 Nb.sub.2 O.sub.5 4-9 Br 0.093-0.180 MgO 0-5 CuO 0.0080-0.0300 CaO 0-5 ______________________________________
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.