Process for the preparation of concentrated aqueous, substantially salt-free solutions of aminotriazinyl reactive dyes, aqueous dye solutions produced thereby and process of dyeing
US4955987A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1985 |
| Grant date | Sep 11, 1990 |
| Priority date | — |
| Expiry date | Dec 6, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09B67/0096
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention describes a process for the preparation of concentrated aqueous, substantially salt-free solutions of aminotriazinyl reactive dyes, which process comprises starting from a dye which contains sulfo groups and one or more radicals capable of reaction with cyanuric halide, said dye being at least partly in the form of the ammonium salt, reacting said dye with cyanuric halide, in the presence of lithium hydroxide, and deionizing and concentrating the salt-containing synthesis solution by a membrane separation process. The so prepared mixed lithium/ammonium salts of the acid aminotriazinyl reaction dyes are readily water soluble and are suitable for the preparation of concentrated storage stable dye solutions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.