Method and means for electrolytic precleaning of substrates and the electrodeposition of aluminum on said substrates
US4126523A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 29, 1977 |
| Grant date | Nov 21, 1978 |
| Priority date | — |
| Expiry date | Apr 29, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D3/44
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Adherent deposits of aluminum can be obtained on metallic substrates by anodic etching of the substrates (reverse current electrolytic cleaning) employing a novel etch solution made as follows: PA1 1. reacting a sufficient amount of aluminum with a hydrogen halide such as HCl, HBr, or HI (preferably hydrogen bromide) in an organic solvent such as benzene or toluene (and in the absence of water) to form a solution in which the concentration of the dissolved aluminum is from 2.0 M to 3.5 M; and PA1 2. then adding hydrogen halide to the resulting solution of 1) above such that the hydrogen ion concentration of the said resulting solution is greater than 1.0 M but below the saturation point of hydrogen halide in said solution. Prior to the actual plating operation, the novel etch solution just described is directed to a plating chamber wherein the metallic substrate is electrocleaned by reverse current anodic etching, i.e., the substrate becomes the anodic terminal of the cell, the reverse of its electric potential in normal electroplating. Then the electroplating electrolyte is directed to the plating chamber to flush out the etch solution. Finally, fresh electroplating electrolyte is…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.