Process for the preparation of concentrated aqueous dye formulations of water-soluble organic dyes by membrane separation and with cross-flow micro-filtration to remove suspended or colloidal solids
US4851011A · kind A · utility
17Cited by
2References
17Claims
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Key dates
| Filing date | Apr 15, 1988 |
| Grant date | Jul 25, 1989 |
| Priority date | — |
| Expiry date | Apr 15, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S8/919
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Concentrated aqueous dye formulations of water-soluble organic dyes are prepared by desalination and concentration of corresponding crude dye solutions by means of membrane separation processes. The effectiveness of the membrane separation process on the one hand and the stability of the dye formulations on the other hand is improved if dye solutions are subjected to cross-flow microfiltration before and/or after the membrane separation process and insoluble constituents are thus removed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.