By three basic units, all
reactive dyes are made up. These three basic units are chromophore, a bridge
and reactive group/groups. To dye cellulosic fibers these dyes are used. Here
formed a covalent bond with hydroxyl group of the fiber by chemically reacting
with fiber when these applied to a cellulosic fiber in an alkaline dye bath.
Types of Reactive Dyes: Basically
reactive dyes are three types which are classified as per the functional group
present,
- Mono functional reactive dyes.
- Bi functional reactive dyes.
- Poly functional or multifunctional reactive dyes.
Properties of Reactive Dyes: The
properties of reactive dyes are given below,
- Reactive dye is anionic in nature.
- Reactive dye is water soluble dye.
- They have better wash and light fastness properties.
- They have better substantively.
- They form strong co-valiant bond with the cellulosic fiber.
- Alkaline condition is must required for dyeing.
- Electrolyte is must for exhaustion of dyes in the fiber.
- A certain amount of dyes are hydrolyzed during application.
- Wide range of color can be produced with reactive dyes.
- Comparatively cheap in price.
Reactive dye is a popular dye in case of cotton dyeing. It gives two types of reaction such as addition and substitution to make covalent bond (the most Strong Bond) which make this dye more suitable.
ReplyDeletePls describe the more about type of reactive dyes
ReplyDeleteMono functional reactive dyes.
Bi functional reactive dyes.
Poly functional or multifunctional reactive dyes.