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In a reactive dye a chromophore contains a substituent that reacts with the substrate. Reactive dyes have good fastness properties owing to the bonding that occurs during dyeing. Reactive dyes are most commonly used in dyeing of cellulose like cotton or flax, but also wool is dyeable with reactive dyes. Reactive dyeing is the most important method for the coloration of cellulosic fibres. Reactive dyes can also be applied on wool and nylon; in the latter case they are applied under weakly acidic conditions. Reactive dyes have a low utilization degree compared to other types of dyestuff, since the functional group also bonds to water, creating hydrolysis.〔Horst Tappe, Walter Helmling, Peter Mischke, Karl Rebsamen, Uwe Reiher, Werner Russ, Ludwig Schläfer and Petra Vermehren "Reactive Dyes"in Ullmann's Encyclopedia of Industrial Chemistry 2000, Wiley-VCH, Weinheim. 〕 ==Usage== Reactive dyes had been tested in the late 1800s involving both adding functionalized dyes to the substrate and then activating the substrate first followed by fixation of the dye. The first commercial success was described in the early 1950s. Rattee and Stephens at the (Imperial Chemical Industries popularlize the chlorotriazines as linkers between the substrate and the chromophore. Trichlorotriazines remain a popular platform for reactive dyes. The chromophore, with an amine functional group, is attached to the triazine, displacing one chloride: : (NCCl)3 + dye-NH2 → N3C3Cl2(NHdye) + HCl The resulting dichlorotriazine can then be affixed to the cellulose fibre by displacement of one of the two chloride groups: : N3C3Cl2(NHdye) + HO-cellulose → N3C3Cl(NHdye)(Ocellulose) + HCl The fixation process is conducted in a buffered alkaline dye bath. An alternative fixation process that is more dominant commercially is the vinylsulfonyl group. Like the chlorotriazines, this functional group adds to the hydroxyl groups of cellulose. The most popular version of this technology is Remazol. The dye is first attached to the ethylsulfonyl group. Reactive dyes are categorized by functional group.〔Stig Hjortshøj (1999), pp. 44–45.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「reactive dye」の詳細全文を読む スポンサード リンク
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