Reactive Dyes

Reactive dyes are introduced to the market by ICI in 1956. These dyes form a covalent bond between the dye and fiber. They are basically a class of highly colored organic substances. They show improved fastness properties. They are primarily used for tinting textiles.

Mechanism of Reactive Dye Fixation

• Utilizes dichlorotriazine as reactive linker
• Nucleophilic aromatic substitution
• Allows for a wide variety of chromophores to be used

REACTIVE 'M' Dyes	REACTIVE 'P' Dyes	REACTIVE 'ME' Dyes	REACTIVE 'HE' Dyes
ALLOZOL Vinyl Sulphone Dyes	ALLOZOL RGB Dyes	REACTIVE HEXL Dyes	ALLOZOL SD Dyes
ALLOZOL RR Dyes

Chemical Binding- The chemical bonds as explained above significantly improves the product's color stability and washability. Thus, no doubt reactive dying of cotton is presently the most popular textile dying process in the world.

Permanency of the color- Fibre Reactive Dyes can be easily said to be the most permanent of all dye types. This is because of an unique quality, unlike other dyes, it can actually form a covalent bond with the Substrate (cellulose or protein molecule).

Easy washing- The fibres that are dyed with reactive dyes can be safely dyed even with white garments without the danger of coloring it.

Vinyl Sulfone Dye (VS)- Vinyl sulfone dyes are moderately reactive. The dyeing temperature is generally 60 degree C and pH is 11.5 that gets applied by utilising a mixture of soda ash and caustic soda. These dyes show excellent fixation properties under proper alkaline condition. A typical example is the Remazol Black B (CI Reactive Black 5).

Bi-functional Dye- A Bi-functional dye is a form of reactive dye that shows more than one type of reactive group in the molecule. These reactive dyes are designed in such a manner to have the capacity to react with the fibre in more than a single way.

Monochlorotriazine Dye (MCT)- Normally these dyes are less reactive than Vinyl sulfone dyes. Reaction can take place in more energetic reaction conditions. That is typically 80 degree C and pH value of 10.5, are essential for a proper fixation on cellulosic fibres. A typical monochlorotriazine dye is shown here.