Coating compositions and method for the treatment of metal surfaces
US4470853A · kind A · utility
28Cited by
9References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1983 |
| Grant date | Sep 11, 1984 |
| Priority date | — |
| Expiry date | Oct 3, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C22/362
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An aqeuous acidic composition provides improved coating for aluminum. The composition comprises from about 10 to about 150 ppm zirconium, from about 20 to about 250 ppm fluoride, from about 30 to about 125 ppm tannin, from about 15 to about 100 ppm phosphate and from about 5 to about 50 ppm zinc, said coating solution having a tannin to phosphate ratio in the range of at least about 1:1 to about 2:1 and a pH in the range of about 2.3 to about 2.95.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.