Photochromic glass and lens
US6177371A · kind A · utility
2Cited by
10References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 9, 1999 |
| Grant date | Jan 23, 2001 |
| Priority date | — |
| Expiry date | Apr 9, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C4/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A fixed tint, photochromic glasses and sunglass lenses produced therefrom. The glasses have R.sub.2 O--Al.sub.2 O.sub.3 --B.sub.2 O.sub.3 --SiO.sub.2 base compositions, contain silver chloride and bromide contents as photochromic constituents and 0.27-0.38% and 0.035-0.060%, both by weight percent, as glass colorants, the NiO:Co.sub.3 O.sub.4 ratio being at least 6:1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.