Process for the preparation of concentrated solutions of anionic dyestuffs and dyestuff additives by cation exchange with cation exchange resin

US4702744A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Joachim Wolff · Odenthal, DE
• Jochen Koll · Odenthal, DE
• Karlheinz Wolf · Leverkusen, DE
• Reinhold Klipper · Neunburg vorm Wald, DE
• Peter M. Lange · Leverkusen, DE

Key dates

• Filing date: May 27, 1986
• Grant date: Oct 27, 1987
• Expiry date: May 27, 2006

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S8/937
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Stable, concentrated aqueous solutions of, in particular, anionic reactive dyestuffs are obtained in a comparatively simple manner by freeing from salts, preferably by means of membrane separation processes, solutions of these substances just as they are obtained in the course of synthesis, and by replacing, with the aid of ion exchangers, the cations which cause sparing solubility.