Disperse Dye Chemistry and Classification
topic
Disperse dyes are hydrophobic, non-ionic, low-MW (250–500 Da) colorants with low aqueous solubility (<1 mg/L), applied as colloidal dispersions (0.5–2 µm particles) stabilised by anionic dispersants. Chemical classes: azo (monoazo, disazo), anthraquinone, and heterocyclic. Classified by sublimation fastness: Class A (low energy, low fastness), B, C, D (high energy, high fastness). Solvatochromic behaviour used to probe dye–fibre interactions.
Role
Disperse dye chemistry is foundational to polyester coloration. The structure–property relationships determining dye solubility, diffusion coefficient, fastness, and ecological profile are central to textile chemistry courses and dye selection practice.