Rose-colored gold alloy compositions with reversible hardness characteristics
US7413705B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 2005 |
| Grant date | Aug 19, 2008 |
| Priority date | — |
| Expiry date | Feb 17, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22F1/14
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Improved 14-karat rose-colored gold alloy compositions include: about 58.5% gold; about 9.0-12.0% silver; about 0.0-0.2% zinc; about 0.3-0.4% cobalt; about 0.0-0.02% iridium; and about 29.0-33.0% copper. Improved 18-karat rose-colored gold alloy compositions include: about 75.2% gold; about 7.0% silver; about 0.0-0.2% zinc; about 0.3-0.4% cobalt; about 0.0-0.02% iridium; and about 17.0-17.5% copper. The hardness of these compositions are capable of being selectively changed between their respective annealed-hardness and age-hardness values. The color of these compositions is between about 5-7 CieLab a* color units and between about 17-21 CieLab b* color units.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.