Disperse Dyes

These  dyes  derive  their  name  from  the  fact  that they  are  insoluble  in  water  and  are, for the purpose of dyeing, dispersed in the dye bath by means of dispersing agents. The fibres most readily colored by disperse dyes are the acetate fibres, polyester, acrylic and nylon.

Properties of Disperse Dyes

1. Generally these dyes are insoluble in water.
2. However they are soluble in hot water to some extent, the solubility increasing with temperature.
3. A feature of disperse dye molecules is their lack of polar groups, evidenced by the insolubility of disperse dyes.
4. Textile materials which have been colored with disperse dyes have a fair to good light-fastness. 
5. Textile materials colored with disperse dyes have a moderate to good wash-fastness. 
6. Some of the disperse dyes are, however, sensitive to nitrogenous fumes, such as may arise from gas, electric or other fibres, suffering serious discoloration, referred to as gas-fading. 
7. Disperse dyes have the ability to undergo sublimation: i.e. they can be vaporized without a significant change in their color, i.e. light-fastness or wash-fastness.