The Chemistry Of Synthetic Dyes. Reactive Dyes May 2026

The part that provides color (usually azo, anthraquinone, or phthalocyanine groups). Solubilising Group: Often sulfonic acid salts ( SO3Nacap S cap O sub 3 cap N a ) that make the dye water-soluble.

The "business end" that reacts with the fibre (e.g., vinyl sulfone or cyanuric chloride). The Chemistry of Synthetic Dyes. Reactive Dyes

A major challenge where the dye reacts with water instead of the fibre, creating "spent" dye that must be washed away. The part that provides color (usually azo, anthraquinone,

Common in dyes. The chlorine atom on the dye molecule is displaced by the hydroxyl ( OHcap O cap H ) group of the cellulose or the amino ( NH2cap N cap H sub 2 ) group of protein fibres. Result: A stable carbon-oxygen or carbon-nitrogen bond. 2. Nucleophilic Addition A major challenge where the dye reacts with

While reactive dyes are safer than many older synthetics (like those using heavy metals), they require large amounts of salt and water for the fixation and rinsing processes. Modern research focuses on "low-salt" dyes and increasing the to reduce chemical waste.

The dye attaches to the fibre through a chemical reaction triggered by alkaline conditions (high pH). There are two main types of reaction mechanisms: 1. Nucleophilic Substitution