PROCESS FOR THE REDUCTION OF THE IONOGENIC HEAVY METAL CONTENT IN THE PREPARATION OF METAL COMPLEX DYESTUFFS

• Main Authors: MROTZECK, UWE, RUSS, WERNER, MISCHKE, PETER, SCHWAIGER, GUNTHER, SITTIG, MANFRED
• Format: Patent
• Language: English; Korean
• Published: 18.01.1997
• Edition: 6
• Subjects: ADHESIVES; CHEMISTRY; DYES; LAKES; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; MORDANTS; NATURAL RESINS; ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES; PAINTS; POLISHES

Free heavy metal ions in water-soluble heavy metal complex dyes are removed from the synthesis solution of the heavy metal complex dye with the aid of one of the compounds stated below or of several such compounds: a) saturated and unsaturated fatty acids having about 8 to 18 C atoms and water-soluble salts thereof; b) the mono- and diesters of orthophosphoric acid and salts thereof of the general formulae (1a) and (1b) in which R denotes a saturated or unsaturated aliphatic radical having about 8 to 18 C atoms and M represents a hydrogen atom or a salt- forming metal which imparts water solubility; c) aliphatic sulphonic acids and water-soluble salts thereof of the general formula (2> R-SO3M (2> in which R and M have the above-mentioned meanings; d) aliphatic phosphonic acids, monoesters thereof and salts thereof of the general formulae (3a) and (3b) in which R and M have the above-mentioned meanings; e) malonic acid and water-soluble salts thereof; f) trimercapto-s-triazine, 2-aminobenzoic acid, 8-hydroxyquinoline and water-soluble salts thereof; g) water-soluble sulphides, such as alkali metal sulphides; h) functionalised water-insoluble polymers which react with metal ions according to the ion exchange principle or form metal chelate complexes. The excess heavy metal ions are precipitated or separated off from the synthesis solution with the aid of these compounds without the heavy metal ions complexed in the dye being attacked.