Apparatus and methods for treating electroless plating baths
US5277817A · kind A · utility
5Cited by
6References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1992 |
| Grant date | Jan 11, 1994 |
| Priority date | — |
| Expiry date | Nov 20, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/912
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Apparatus and methods for removing polyvalent by-product anions, e.g. borate and orthophosphate ions, from electroless metal plating baths employing borane or hypophosphite reducing agents and typically comprising monovalent anions or neutral zwitterions as metal chelant and/or counterion. The apparatus and methods of this invention employ (a) solvent extraction to remove metal species for recycle, (b) anion filtration to separate polyvalent anions from neutral zwitterions and monovalent anions and (c) ion exchange units to remove metal and metal chelant species from polyvalent anion-containing waste streams.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.