What is the meaning of reactive dyes?
The dye that forms an integral part of the fiber by creating a covalent link with the fiber is called reactive dye. At present, most of the reactive dyes are being used in the whole world including Bangladesh. This is because the dye is easy to use, relatively inexpensive, and available in many different colors, and can be used in all natural fibers. Besides, the brightness and durability of the color are also good. https://bdfabric.com/important-things-of-vat-dyeing-process/
What is the meaning of reactive dyes? In 1895, Cross and Bevan, two scientists, considered covalent bonding with textile fibers. Then in 1952, a scientist named Guthrie provided an important explanation for the reaction of dye molecules with fiber. Based on these, the British ICI company succeeded in inventing the first reactive color in 1956. In 1956, the company commercialized reactive dyes and marketed them, as well as many companies.
It forms a covalent link with reactive dye fiber and becomes a part of the fiber. Such dye molecules have some reactive groups, which react with the functional groups of fibers, such as the OH group of cellulose and the NH2 group of protein fibers. This is why all these dyes are called fiber reactive dyes.
Properties of reactive dyes:
The properties of reactive dye are discussed below.
(1) During the dyeing process, the reactive group of the dye forms a covalent bond with the fiber and a portion of the fiber remains in the account.
(2) It has a high weight fastness. However, its level depends on the stability of the covalent bond.
(3) Brightness and rubbing fastness of this dye are comparatively higher than VAT and Azoic dye.
(4) It is soluble in water.
(5) It is commonly used to dye cellulose and protein fibers.
(6) Dyeing process is usually done in an alkali medium.
(7) All types of shades are available by the reactive dye.
(9) The method of application of this dye is very simple.
(10) Regenerated cellulose fibers can be dyed with this dye.
(11) There is no loss of dye in gas fading and dry cleaning.