Procion dyes

Procion dyes A group of azo dyestuffs which can form covalent bonds to cellulose by reactive groups. 

Procion dyes Procion H Procion H dyes Procion HE Procion H-E dyes Procion MX Procion MX dyes Procion P dyes Procion reactive dyes Procion Red H-E 7B Procion SP Procion supra dyes Procion T PROCOmi Proconvertin [9001-25-6] Proctitis... 

Other modifications of acid wool dyes have groups which react by nucleophilic substitution of basic groups ia proteia fibers (NH2 groups, etc). The iatroduction of Procion dyes by ICI ia 1956 was the most important development ia the field of technological azo dye chemistry. Chemically, many of the reactive dyes are prepared from the group of the anionic monoazo dyes (see Dyes, reactive). 

Scheme 1.1 The reaction of Procion dyes with cellulosic fibres...

Scheme 8.1 Reaction of Procion dyes with cellulose...

It is possible to tailor dyes, by use of the stepwise reactivity of the chlorine atoms in cyanuric chloride (B-59MI11200), to a variety of applications. For example, in structure (16), two molecules of cyanuric chloride may be reacted with one molecule of a suitable diamine, such as 4,4 -diaminostilbene-2,2 -disulfonic acid, at 0-5 °C and then the subsequent bis-dichlorotriazinyl product condensed with two molecules of an azo dye with a primary amino group at 35-40 °C. The resultant dyes are applied very efficiently to cellulosic fibres at 85-90 °C with very little dye remaining in the dyebath. The same molecule may also be prepared by condensation of the dye with cyanuric chloride at 0-5 °C and then with the diamine at higher temperature. Dyes more suitable for printing application may be prepared by condensation of a dye-amino group with cyanuric chloride followed by a diamine and then a further molecule of cyanuric chloride. The various applications are manifested in the various ranges of ICI s Procion dyes. 

Starches can be chemically dyed by reacting a procion dye with 2,4,6-trichloro-triazine or 2,4-dichloro-triazine, followed by reaction with alkaline starch [170,171]. A chloro group on the triazine ring of the dye derivative is replaced by a starch hydroxyl group to form a stable... 

The Procion dyes, on account of the sulphonic acid groups in their molecules, are readily soluble in water. In neutral solution they have sub-stantivity towards cellulose similar to that of very low affinity direct dyes, a wet-fastness of a low order, and they exhaust better in the presence of... 

Extremely good fastness on the cellulosic component can be obtained with reactive dyes. The cold dyeing members are preferable because the conditions of alkalinity and temperature necessary to fix the high-tempera-ture reactive dyestufiFs would be harmful to the wool. When Procion dyes are applied cold the protein fibre is left practically unstained, unless it has been chlorinated previously, and must be brought up to shade with neutral dyeing acid dyes such as those on page 575. The Procion dyes which have been found suitable are ... 

The thoroughly wetted-out goods are dyed in a cold liquor with the Procion dye and 15 to 20 parts per 1000 of coimnon salt. Fixation on the cellulose is brought about with 1-5 to 3 parts per 1000 of trisodium phosphate in... 

Cyanuric chloride is also used for the introduction of a link group into dyes. The S Ar reactivity of the chlorotriazine system leads to covalent bonding with the OH groups of cellulosic fibres, e.g. cotton (reactive dyes, e.g. cibacron and procion dyes, e.g. 12 [175]) ... 

Other major advances in this sphere have been in colour-fastness, i.e. resistance to the dye being washed out when the garment is cleaned. For example, the Procion dyes, developed by ICI, actually chemically bond to cotton, rather than attaching by the more usual physical type of adherence to the fibre. This clearly leads to greater colour-fastness. 

These became commercially available in 1977 as Procion dyes, but were later withdrawn because of technical drawbacks experienced during processing [7]. The simple process requires a second agent which is dicyandiamide and it can be summarised in a simple way as (12.50). Typical dyes... 

The most important reactive dyes in commercial use for application to cellulosic fibres in which the fibre-reactive groups react by nucleophilic addition are the Remazol reactive dyes. These dyes, based on the vinylsulfone reactive group, were introduced by Hoechst soon after the launch of the Procion dyes based on the triazine system by The chemistry of the process in which vinylsulfone... 

The suitability of macroporous agarose derivatized with diverse Procion dyes or Cibachron Blue for substrate-elution chromatography of carboxypeptidase G has been investigated. A mercapto-derivative of macroporous agarose has been used in separating the principal glycoproteins from other proteins in human red-cell membranes. ... 

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