Surface-treated aluminum material and method for its surface treatment
US5462634A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 31, 1995 |
| Grant date | Oct 31, 1995 |
| Priority date | — |
| Expiry date | Jan 31, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/44
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An aluminum material is surface-treated with an aqueous solution containing 0.005 mol/lit. or more of a chelating agent and 5 g/lit. or more of an organic amine and having 100 ppm or less of phosphoric acid radical ion concentration and 500 ppm or less of sulfuric acid radical ion concentration, until its surface has a color tone (S) of: EQU S=(X.sup.2 +(3.388Z-3Y.sup.2).sup.1/2.gtoreq.70 wherein X, Y and Z represent the tristimulus values of color. The aluminum material can be surface-treated while setting the treating conditions on the basis of a specific color tone detectable by colorimetry, without relying on experience and intuition. The surface-treated aluminum material can have a good anticorrosion, have good color change preventive properties, a good adhesion of coatings and a beautiful surface appearance. The present surface treatment is effective as anticorrosive treatment for itself, but can be also effective when this treatment is carried out as a pretreatment and further surface treatment is carried out thereon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.