Factors considered for selection of dyes

Factors considered for selection of dyes :

 Dye selection depends upon the following factors :

1.    Selection of dyeing method :

§  Batch wise / Discontinuous / Exhaustion method

§  Semi-continuous method, i.e.

ü Pad batch method

ü Pad roll method

ü Pad jig method

§  Continuous method, i.e.

ü Pad steam method

ü Pad dry method

ü Pad thermofix method

2.    Brand selection :

§  Hot brand    : Less reactive dye (temp 72°c-93°c)

§  Medium brand       : Medium reactive dye (temp 60°c-71°c)

§  Cold brand   : Most reactive dye (temp 32°c-60°c)

3.    Economy of production.

4.    Availability of dyes.

5.    Storage facilities.

6.    Bond stability i.e. kind of bonding.

7.    Fastness of the dye i.e. wash, light, rubbing fastness.

·       Dye Terminology :

v Exhaustion

v Proportion of dye taken up by the fiber at any stage of the process relative to the amount originally available.

v Fixation

v Proportion of dye remaining on the fiber at the end of the process relative to the amount originally available

v Fastness

v Resistance to fading due to washing, light, etc.