Process for regenerating chemical copper plating solution
US4324629A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 1980 |
| Grant date | Apr 13, 1982 |
| Priority date | — |
| Expiry date | Jun 17, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S204/13
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
During recyclic use of a chemical copper plating solution, counter anions to copper ions, anions formed by oxidation of a reducing agent, and carbon dioxide by absorption of carbon dioxide from air, which all have an inhibiting effect upon the plating, and also sodium ions having no inhibiting effect are accumulated in the plating solution. These accumulated ions can be removed by electrodialysis. Particularly, regeneration can be satisfactorily regenerated by adjusting the pH of used chemical plating solution to 2-11 before the electrodialysis, and using a selectively monovalent anion permeable membrane as an anion exchange membrane at the electrodialysis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.