Textilelearner.blogspot.com-Dyeing Process Process of Dyeing Technique

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    Fabric dyeing

    Dyeing Process | Process of Dyeing TechniqueDyeing Process:Dyeing is governed by three factors, the dye, the fiber and the dye liquor. All the three lead an independentassistance which influences the technique of dyeing. A dye must be water soluble in order to dye textile materials.It may be soluble by nature of its chemical interference. The dyeing process can thus be considered as takingplace in three phases

    Attachment of the dye molecule tothe surface of the fiberPenetration into the intermolecularspaces as well as diffusion throughthe fiber &Orientation (and fixation) along thelong chain molecules.

    The solution of the dye from which it isapplied is called the dye bath. A dyemay have direct affinity for a fiber (orvice versa) i.e., it is held by the fibreeither physically (absorption) orchemically (combination) as soon as thefiber is immersed in the dye bath.

    Accumulation of the dye in the fiber is agradual process, the rate of suchbuilding up being referred to as the 'rateof dyeing'.

    1. This rate of dyeing is governed by the condition of the dye bath, namely concentration of dye, temperature,and presence of electrolytes; it is proportional to all three factors.

    2. The rate of dyeing is also influenced by the Material to liquor which is expressed by a fraction, e.g. 1:20,which means one part (by weight) of the textile material dyed in twenty times its weight of dye bath.

    3. The rate of dyeing decreases with increasing ratio of goods to liquor.

    Dyeing is carried out to produce a certain Shade by which is meant a certain color, difference in shade beingdue to different Hue. A blue shade may, for instance, have a greenish or a reddish hue.The amount of dyeneeded for the production of a certain depth of shade is expressed as a percentage of the weight of the material.A 1% dyeing represents a shade produced by the coloring of 100 lbs. of material with one lb. of (commercial) dyeunder well defined dyeing conditions. It is necessary to define these conditions because of their influence on theexhaustion of the dye bath. Exhaustion determines that amount of dye which is taken up the fiber or in directly,that amount which remains in the dye bath after equilibrium between dye and fiber is reached, i.e., at that pointwhere no further dyeing takes place.

    Dyeing Process | Process of Dyeing Technique