Organic solderability preservative compositions
US5858074A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1997 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Jul 29, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F11/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Known organic solderability preservatives (OSP) contain an azole compound and are applied on a copper surface from an acidic solution. The OSPs are not visible to the naked eye when applied. A number of dyes compatible with the OSP solution and not interfering with solderability has been identified. The composition containing such a dye can produce a layer which is visible to the naked eye when applied even in a thin layer. The suitable dyes contain a cationic imine group having the general formula ##STR1## where X.sup.- is an anion such as chloride, iodide, sulphate, etc., or an organically bonded anionic group such as sulphonate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.