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10 Types of Dyes with their Properties and Dyeing Mechanism

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What is a Dye? A dye is a coloring substance that is used for giving color to different substances or altering the color of something. A dye chemically bonds to the substrate to which it is being applied and has an affinity to adhere to the solvent medium. A dye contains two groups that are chromophore and auxochrome groups in which a chromophore is a color-bearing group that is responsible for dye color whereas auxochrome is a color helper which is responsible for dye fiber reaction. Examples of dyes: Indigo dye , Phthalein dyes , Alizarin , etc. 10 Types of Dyes 1. Reactive Dyes Reactive dyes are those dyes that form a covalent bond between the dye and fiber. These dyes have a reactive group like halo-heterocycle or an activated double bond which once applied to a fiber with a hydroxyl group on the cellulosic fiber. In a reactive dye, chromophore has a substituent that is activated and allowed to directly react to the surface of the substrate. Some common examples of reactive dy...