Lightly tinted glasses of variable transmission
US4757034A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 30, 1987 |
| Grant date | Jul 12, 1988 |
| Priority date | — |
| Expiry date | Mar 30, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03C4/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This invention relates to the production of lightly tinted, photochromic glasses having base compositions consisting essentially, in weight percent, of ______________________________________ SiO.sub.2 46-60 SrO 0-6 B.sub.2 O.sub.3 16-28 BaO 0-6 Al.sub.2 O.sub.3 4-11 P.sub.2 O.sub.5 0-5 ZrO.sub.2 2-6 TiO.sub.2 0-3 Li.sub.2 O 1.5-5 Ag 0.08-0.18 Na.sub.2 O 0-6 Cl 0.06-0.26 K.sub.2 O 2.5-9 Br 0.08-0.18 MgO 0-3.5 CuO 0.0001-0.0020 CaO 0-6 ______________________________________ Glass color can be adjusted by introducing in excess of the above base composition, at least one of the following colorants in the indicated proportions of ______________________________________ Pd 0.00003-0.00015 Er.sub.2 O.sub.3 0.2-1.3 SnO.sub.2 0.05-0.3 Nd.sub.2 O.sub.3 0-0.7 Fe.sub.2 O.sub.3 0.05-0.15 Co.sub.3 O.sub.4 0-0.0080 NiO 0.005-0.015 ______________________________________
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.