The Chemistry Of Synthetic Dyes. Reactive Dyes Site

Generally requires salt to drive the dye into the fibre and alkali to fix it. 🌍 Environmental Impact

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 The Chemistry of Synthetic Dyes. Reactive Dyes

The "business end" that reacts with the fibre (e.g., vinyl sulfone or cyanuric chloride). Generally requires salt to drive the dye into

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. A major challenge where the dye reacts with

A major challenge where the dye reacts with water instead of the fibre, creating "spent" dye that must be washed away.

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.

Typical of dyes (like Remazol). In an alkaline bath, the dye undergoes an elimination reaction to form a vinyl sulfone group, which then adds across the fiber's functional groups. Result: A highly durable covalent linkage. ⚡ Key Properties