Reactive Dye: Why so called?

[Tanvir Ahmed Chowdhury]

Reactive dyes react with the fibers.
   Mainly react with cellulosic fibers
   e.g. cotton, jute, bast fibers, viscose, flax
It can be applied to protein fibers e.g. wool & silk.
Reactive dye contains reactive group and this reactive group makes covalent bonds with the fibers and becomes part of the fiber.
The general formula of Reactive dye can be written as follows:
D-X-Y
Here    D --> Chromophore of Dye post
   X --> Bridge
   Y --> Functional group
D-X-Y + Fiber --> D-X-Y-Fiber Covalent bond.
Reactive dyes water soluble
D-F + Cell-OH --> Dye-F-O-cell   F = Functional group
D-F + H-OH --> Dye-F-OH
         Hydrolysis