Classification of reactive dyes on the basis of reactive group, reactivity and temp

Classification of reactive dyes

Reactive dyes may be classified in various ways as below:

1)    On the basis of reactive group:

a)    Halogen (commonly chlorine) derivatives of nitrogen containing heterocycle, like 3 types-

·       Triazine group

·       Pyridimine group

·       Quinoxaline dyes

                  Example:

                      Triazine derivatives: procion, cibacron.

                      Pyridimine derivatives: reactone

                      Quinoxaline derivatives: levafix.

b)    Activated vinyl compound:

·       Vinyl sulphone

·       Vinyl acrylamide

·       Vinyl sulphonamide.

                    Example:

                       Vinyl sulphone: remazol

                       Vinyl acrylamide: primazine

                       Vinyl sulphonamide: levafix.

2)    On the basis of reactivity:

a)    Lower reactive dye:

 Here ph is maintained 12-12.5 by using NaOH in bath.

b)    Medium reactive dye: here pH is maintained 11-12 by using Na₂CO₃ in dye bath.

c)    Higher reactive dye: here pH is maintained 10-11 by using NaHCO₃ in dye bath.

3)    On the basis of dyeing temperature:

a)    Cold brand: 

   These types of dyes contain reactive group of high reactivity. So dyeing can be   done in lower temperature i.e. 32⁰-60⁰C.

     For example: PROCION M, LIVAFIX E.

b)    Medium brand:

 This type of dyes contains reactive groups of moderate reactivity. So dyeing is done in higher temperature than that of cold brand dyes i.e. in between 60⁰-71⁰C temperatures.

   For example, Remazol, Livafix are medium brand dyes.

c)    Hot brand:

 This type of dye contains reactive groups of least reactivity. So high temperature is required for dyeing i.e. 720-930 C temperature is required for dyeing.

   For example PRICION H, CIBACRON are hot brand dyes.