Soluble dyes properties

There is a wide variety of dyes unique to the field of hair coloring. Successive N-alkylation of the nitrophenylenediamines has an additive bathochromic effect on the visible absorption to the extent that violet-blue dyes can be formed. Since the simple A/-alkyl derivatives do not have good dyeing properties, patent activity has concentrated on the superior A/-hydroxyalkyl derivatives of nitrophenylenediamines (29,30), some of which have commercial use (31). Other substituents have been used (32). A series of patents also have been issued on substituted water-soluble azo and anthraquinone dyes bearing quaternary ammonium groups (33). 

Both acids and alkalis will adversely affect the material. Strong alkalis and acids will cause decomposition. The water absorption is high and consequently casein is easily stained. As a corollary to this it may be dyed without difficulty. Acidic and basic water-soluble dyes are normally used. Typical properties of casein plastics are given in Table 30.2. 

Polymethines, typical soluble dye applications, 7 376t Polymethylene, 20 149 Polymethylene wax, 26 220 Poly(methyl methacrylate) hollow fiber membranes, 16 21 Poly(methyl methacrylate) sheet, properties of, 16 292t Poly(methyl methacrylate) (PMMA),... 

Copper phthalocyanine derivatives are well established as turquoise blue direct and reactive dyes for cellulosic fibres. Chlorosulphonation at the 3-position, followed by hydrolysis, yields sulphonated direct dyes such as Cl Direct Blue 86 (5.32 X = H) and Blue 87 (5.32 X = S03Na). Solubility and dyeing properties can be varied by introducing four chlorosulphonyl groups, some of which are hydrolysed and some converted to sulphonamide by reaction with ammonia or alkylamines. This approach is also the main route to reactive dyes of the copper phthalocyanine type. The reactive system Z is linked to a 3-sulphonyl site... 

While the properties of (soluble) dyes are determined almost exclusively by their chemical constitution, application characteristics of pigments—which are by definition insoluble in the medium in which they are applied (see Sec. 1.1) — are largely controlled by their crystalline constitution, i.e., by their physical characteristics. This is discussed in the next chapter. 

Based on the excellent solubility and reducing properties of amine boranes, they are often used for the stabilization and purification of industrial materials. Further, they are applied as additives in hydrocarbon fuels and in lubricating oils, as polymerization catalysts, as ingredients in photographic processing and in the electroplating industry.169 High stability towards hydrolysis and oxidation makes cationic boron chelates useful as water-soluble dyes.170... 

Ink-Jet Dyes for Special Media. Anionic water-soluble dyes (19) are the dyes of choice for ink-jet printers. The properties required of these ink-jet dyes include high color strength, good stability in the appropriate solvent, good fastness properties (especially to light and water), and high purity. Obviously, the dyes must... 

The adsorptive properties of colloids find some application in analysis, e.g. in the removal of phosphates by tin(IV) hydroxide oxide in the presence of nitric acid (Section V.13) and in the formation of coloured lakes from colloidal metallic hydroxides and certain soluble dyes (see Section III.23 and III.35 for aluminium and magnesium respectively). There is, however, some evidence... 

Recently, we are also able to perform liquid-liquid extractions of water-soluble dyes from water to organic solvents like toluene using the unimolecular dendritic micelles as extractants. These guest-host properties of the modified poly(propylene imine) dendrimers make use of the basic nature of the interior of the dendrimer. Therefore, it is possible to transfer dyes like Bengal Rose into toluene. Although simple tri-octylamines are capable of transferring these dyes as well, it is evident from the experiments that unimolecular dendritic inverted micelles are much more selective, probably due to the shielding effect of the apolar shell [70]. 

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