DyeStuff
Dyestuffs are organic and
inorganic substances which consists of chromophore groups, can change the
physical and chemical properties of any substance can absorb light and reflect
lights to show color. They are unsaturated complex compound.
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| Different Types Of Dyes |
Characteristics of dyestuff
→It must contain chromophore group
→Chromophore group can be
different types like –NO2,-NH2,-CO2,-N=O
→It must make dilute solution when
it mixed with H2O nut it can also insoluble too.
→Dyestuff must penetrate into the
fiber
→It must have stability and
fastness property
Different types of Dyestuffs in relation between the fiber substrate:
Reactive Dye: Applicable for cotton, linen, viscose,, wool, silk. The dyestuff forms a chemical link with the fiber. It has very good fastness properties.Disperse Dye: Applicable for polyester, nylon, acetate. It is water in soluble applies from dispersions diffuse into the fiber at high temperature. It has also good fastness.
Basic dye; it is suitable for acrlylic fibres. It reacts with acidic groups or mordants in the fiber. It is also good fastness properties on acrylic fibers.
Direct dye: Applicable for cotton, linen, viscose, silk. Simple diffusion into the fibre, from aqueous solution. It has relatively poor fastness properties to light, washing and perspiration. These fastness properties can be improved by after treatment.
Vat dye: Applicable for cotton, linen, viscose. These insoluble dyestuff is made soluble in a reducing vat so that it can diffuse into the fibre. After diffusion is complete, it is then re-oxidised into it’s in soluble from. High fastness to washing, chlorine, boiling, light, rubbing and perspiration.
Acid dye: Applicable for wool, silk, nylon. Applied from an acidic dyebath. The fastness properties of this dye-stufff depends on the fibre types.