Zinc/nickel/phosphorus coatings and elecroless coating method therefor
US5304403A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1992 |
| Grant date | Apr 19, 1994 |
| Priority date | — |
| Expiry date | Sep 4, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C18/48
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In a preferred method, a zinc-rich alloy coating is applied to a substrate using an electrolysis deposition solution which contains a metal salt of zinc and a metal salt of nickel each in an amount sufficient to provide a weight ratio of zinc to nickel (Zn:Ni) of at least about 1:1; a phosphorus-containing reducing agent in an amount sufficient to cause reduction of the zinc and the nickel to ions thereof; sufficient complexing agent to maintain the nickel ions and the zinc ions in solution; and a buffer in an amount sufficient to achieve a desired pH. Preferably, the surface of the substrate is pretreated or precatalyzed before deposition by a sensitizing step using tin and an activating step using palladium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.