| 摘要 |
Process of preparing a concentrated solution of a water-soluble anionic azo dye containing 1 to 4 sulfonic acid groups by diazotization and coupling of a diazo and coupling component, respectively, in the solvent or solvent mixture required for the concentrated solution which should have as essential solvents water and/or water-soluble or water-miscible organic solvents other than carboxylic acids. Diazotization is carried out with a nitrous acid ester of a hydroxy-substituted aliphatic hydrocarbon, e.g., an alkyl nitrite. The process provides highly stable concentrated or stock solutions of unlimited miscibility with water for use in continuous dyeing methods.
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