Monochlorotriazinyl dyes

When two of the chlorine atoms are substituted, for example with amino or alkoxyl groups, monochlorotriazinyl dyes 2 are obtained. These are considerably less reactive, and hence react with cellulose in the exhaust dyeing process only at relatively high temperature (80°C). Such dyes are especially advantageous for printing [14],... 

The reactivity of monochlorotriazinyl dyes can be increased by replacing chlorine with fluorine (3), which allows the exhaust process to be carried out at 40°C [15],... 

Reaction of monochlorotriazinyl dyes with tertiary amines also yields highly reactive dyes 4. One advantage conferred by the ammonium groups in these dyes is high water solubility [16]. 

Their aqueous solutions, therefore, are more stable but they do not react with cellulose so readily and the temperature of dyeing must be increased to 60° to 70°C (149° to 158°F) and, in some cases, as high as 90° to 95°C (194° to 203°F). There are ranges of monochlorotriazinyl dyes such as the... 

The rate of fixation of the monochlorotriazinyl dyes is very much slower. The result is that there is abundant opportunity for the normal acid dyeing mechanism to give uniform distribution of the dye molecules before they become permanently anchored by covalent bond formation. It has been found that, for some unknown reason, cationic surface active compounds tend to reduce skitteriness, if a non-ionic compound is also present to prevent the precipitation of the cation-dye complex. In order to prevent foaming which can become troublesome the addition of a silicone antifoaming product has been recommended. 

Cibachron Blue, a monochlorotriazinyl dye, has proved valuable for the covalent dyeing of amylose, starch, cross-linked... 

Procion dyes are chemically reactive dyes that have been formed by reaction of a dye with 2,4,6-trichlorotriazine or 2,4-dichlorotriazine [31]. Achloro group on the triazine ring of the dye is replaced by a polysaccharide hydroxyl group to form a stable, covalent linkage between the dye and the polysaccharide (reaction 7.17). Cibachron Blue, a monochlorotriazinyl dye, has been used to produce dyed complexes (reaction 7.18) with amylose, amylopectin, starch [32,33], cellulose [34], chitin [35], and dextran [32,36]. 

The concentration of the immobilized ligand should be approximately 8.5 /imol/g dry gel molar absorption coefficient for Procion blue MX-R in glycerol/H20 (1 1, v/v) equals 11 6001/mol/cm. For silica gels the pH should never exceed 8.5 at a maximum temperature of 40°C and even then for a few hours only. For this reason, the performance of the above method is poor when coupling monochlorotriazinyl-dyes whidi... 

Migration Exhaust Technique for Less than 0.5% Depth of Shade. Start at 50°C with sequestrant at pH 7.0. Add dye over 20 min and raise temperature to highest safe level depending on the dye (95°C with monochlorotriazinyl reactive system) at a rate of 1.5°C/min. Hold for 20 min and cool back to dyeing temperature. Alkali is portionwise added, or mechanically dosed, over 20 min and after a further 30 min the dyebath is dropped and the washing sequence begun. 

The dyes described in [8] entered the market for wool in 1952 under the trade name Remalan, followed a year later by the Cibalan dyes from Ciba-Geigy, which contained monochlorotriazinyl reactive groups [10], In 1953 Rattee and Stephen... 

Mixed-anchor systems in reactive dyes were first described in 1959. Such bifunctional dyes were first marketed in the early 1980s. These products are characterized by two anchors with differing reactivities a more reactive 2-sulfo-hydroxyethylsulfonyl group and a less reactive monochlorotriazinyl residue. An example of such a system is 14 ... 

The reactivity of the dyes appears to lie somewhere between the di- and monochlorotriazinyl colours. 

Dyeings of very good fastness can be obtained in a one-bath method. The polyamide fibre is dyed with a procinyl dye and the cellulosic fibre with a monochlorotriazinyl dyestuff. The dyeing is carried out forone hour at a temperature not exceeding 85°C (185°F) in a liquor containing 100 g/1 of common salt. After one hour trisodium phosphate (crystalline) equivalent to 15 g/1 is added to bring about the fixation of the reactive dyes. 

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