- Reactive dye
In a reactive dye a
chromophore contains asubstituent that is activated and allowed to directly react to the surface of the substrate.History
Reactive dyes first appeared commercially in 1956, after their invention in 1954 by Rattee and Stephens at the
Imperial Chemical Industries Dyestuffs Division site inBlackley ,Manchester ,United Kingdom .Usage
Reactive dyes are used to dye cellulosic fibres. The dyes contain a reactive group, either a halo
heterocycle or an activated double bond, that, when applied to a fibre in analkaline dye bath, forms achemical bond with anhydroxyl group on the cellulosic fibre. Reactive dyeing is now the most important method for the coloration of cellulosic fibres. Reactive dyes can also be applied onwool andnylon ; in the latter case they are applied under weaklyacidic conditions. Reactive dyes have a low utilization degree compared to other types of dyestuff, since the functional group also bonds to water, creatinghydrolysis .
=Vinyl sulfone
activated double bond
40˚
Remazol
-
Vinyl amide
activated double bond
40˚
RemazolBifunctional
Dyestuffs with only one functional group sometimes have a low degree of fixation. To overcome this dyestuffs containing two different reactive groups (i.e. one monochlorotriazin and one vinyl sulfone) were created.
Dyestuffs containing two groups are also known as bifunctional dyestuffs, though some still refers to the original combination. Other types of bifunctional dyes has been introduced. The first bifunctional dye made where more tolerant to temperature deviations (better proces). Other bifunctionals are created, some with fastness (better quality) or only fixation degree (better environment/economy) in mind.
Trifunctional dyestuffs also exist.
ee also
*
Carbene dye sFootnotes
References
External links
For more info [http://www.pburch.net/dyeing/chemistry_reactivedyes_lesson.shtml Fundamental Chemistry of reactive dyes]
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