Abstract:
A process for the manufacture of an azo metal salt pigment, wherein a transparent or translucent alkaline aqueous solution of a resin and a dispersant of formula (1) or formula (3) is added to an azo compound, said formula (1) beingYCO--OM (1)whereinYCO is the residue of a polyester derived from a hydroxycarboxylic acid, andM is H, a metal or optionally substituted ammonium, and said formula (3) beingYCO--Z--R (3)whereinZ is a divalent bridging group containing an oxygen or a nitrogen atom through which Z is attached to the carbonyl groupR is a primary, secondary or tertiary amino group or a salt thereof with an acid, or a quaternary ammonium salt group, andYCO is as herein defined.
Abstract:
The invention relates to a process for the preparation of a metal complex dye under production conditions, which comprises reacting at least one dye with a metal donor, adding said metal donor or said dye discontinuously before the end point of the metallizing is reached, and determining the end of the metallizing voltametrically.The process makes it possible to prepare metal complex dyes in good yield and purity.
Abstract:
Stable, concentrated, liquid preparations of 1:2 metal complex azo or azomethine dyes containing at most one sulfonic acid group are obtained by metallizing the metal-free azo or azomethine intermediates in form of their moist, almost salt-free washed, filter cakes with aqueous slurries of complex forming, preferably cobalt or chromium salts. Without isolation of the thus obtained metal complex dyes the dye slurries are then in situ converted into the stable, concentrated dye preparations by adjusting them to a final dye concentration.The dye preparations are produced in a very economic manner by avoiding any isolation of the metal complex dyes after the metallization step and by considerably reducing the amounts of effluents.The dye preparations obtained are suitable for the preparation of dye-baths or printing pastes which may be used in particular for dyeing and printing textile materials made of natural or synthetic polyamide fibres, and further of leather and paper.
Abstract:
A method of directly producing copperized azo-dyestuffs of predetermined inorganic salt content is disclosed wherein an ortho, ortho'-dihydroxyazo-dyestuff is reacted with about one molar equivalent of a copper (II) compound consisting of from 1.0 to 0.1 molar equivalent of a non-salt-forming copper compound selected from CuCO.sub.3.Cu(OH).sub.2, 2CuCO.sub.3.Cu(OH).sub.2, Cu(OH).sub.2, CuO and mixtures thereof, and correspondingly from 0 to 0.9 molar equivalent of a salt-forming copper (II) compound selected from CuSO.sub.4, CuCl.sub.2 and Cu(NO.sub.3).sub.2. The disclosed method provides standard strength copperized dyestuff compositions at increased yields and without the need to precipitate the product from the reaction solution.