Corrosion resistant coatings for aluminum and aluminum alloys
US6375726B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2000 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Oct 31, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C2222/10
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention is for the protection and surface treatment of aluminum, aluminum alloys and coated aluminum substrates against corrosion. The aluminum substrates are treated with an acidic aqueous solution containing small but effective amounts of at least one trivalent chromium salt such as a trivalent chromium sulfate, at least one alkali metal hexafluorazirconate such as potassium hexafluorozirconate in combination with small but effective amounts of at least one water soluble or dispersible thickening agent such as a cellulose compound and at least one water soluble surfactant. The corrosion resistant aluminum substrates of this invention have improved adhesion for overlaying coatings e.g. paints and a lower electrical resistance contact.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.