Direct fast violet

Direct fast violet RR is formed if m-toluidine is used in place of cresidine (amino-cresol ether). 

Solophenyl Fast Blue Green BL direct green 27 Solophenyl Brilliant Blue BL direct blue 106 Chlorantine Fast Violet 2RLL direct red 83 Solar Yellow R direct yellow 37... 

Carmoisine A Chrysoine S Cochineal red A Cresyl fast violet Crystal violet Direct red 83 Eriochrome blue SE Eriochrome black T Eriochrome blue black B Eriochrome black T Eriochrome blue SE Erythrosine FD C red dye No. 2 FD C red dye No. 4 FD C red dye No. 40 Lyrazol fast red Methyl orange Methyl orange Methyl red Methyl red Orange II Orange GGN Quinolidine yellow Para red Phloxine B Ponceau 6R Procion Red Saffron Scarlet GN... 

The application range designated by this generic name in the Colour Index incorporates those acid, direct and mordant dyes with substantivity for leather and satisfactory fastness on that substrate [55]. It is a commercially important sector, the number of products listed being exceeded only by the complete acid or direct dye ranges. As expected from the sources of this selection, about 85% of leather dyes are azo compounds (35% disazo, 30% monoazo, 20% metal-complex monoazo) and the remainder are mainly yellow to orange stilbene dyes and anthraquinone or triarylmethane types in the violet to green sectors. 

Unfortunately, the fluorescent effect is not directly proportional to the concentration of colorant present, since there is considerable quenching if quite low concentrations are exceeded. The light fastness of the fluorescent pigments is also less than that of many other organic pigments now available, but improvement can be achieved using overlayers containing ultra-violet absorbers. This is an area in which further research will clearly be needed. 

The members of this class dye wool and silk directly, but cotton only when the latter is mordanted by tannin. They are fast neither to acids nor to alkalis for reasons which depend on important alterations in the compounds. If a little dilute hydrochloric acid is added to an aqueous solution of crystal violet the colour changes to green. One N(CH3)2-group takes part in the change and there is formed the salt with two equivalents of acid ... 

Violets and heliotropes of the benzo, benzoform, bnlliant Congo, chloramine, chlorazol, Columbia, diamme, diaml, dianol, diazo, diphenyl, direct, formal, naphthamine, oxamme, oxydiamme, para, rosantbrene, tnsulphon, etc, senes Azo marne, azo violet, benzo fast heliotrope, chlorantme lilac, hessian purple V-olet ... 

Quinacridones. Much effort was expended to carry the hue of phthalocyanines in the other direction to produce reds and violets with outstanding fastness properties, but these efforts proved to be unsuccessful. Hov/ever, in the 1950s a number of developments did take place with other chromophores in this color range to produce new lines of outstanding pigments. The development and commercialization of quinacridone pigments by Du Pont was one of these developments. 

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