The document discusses the discovery and development of reactive dyes for dyeing cotton fabrics. Reactive dyes were discovered in 1956 and allow for covalent bonding between dye molecules and cellulose fibers. They are classified as mono-functional or bi-functional depending on whether they contain one or two reactive groups. Common reactive groups include dichlorotriazine, monochlorotriazine, and vinyl sulphone. The document also describes different dyeing methods for reactive dyes such as batch, pad-batch, pad-dry, and pad-dry-bake and provides statistics on global cotton dyeing with reactive dyes.

3. REACTIVE DYES BASED ON TRIAZINE

4. SCHEMATIC REPRESENTATION OF TRIZINE REACTIVE DYES

5. REACTIVE DYES BASED ON VINYL SULPHONE

8. Typical mono functional reactive groups

10. BIFUNCTIONAL REACTIVE DYES CHROMOPH-ORE CHROMOPHORE BRID-GE REACT-IVE GROUP REACT-IVE GROUP

11. Homo and Hetrobifunctional reactive dyes

14. DYEING CYCLE

18. PAD-BATCH METHOD

22. PAD-DRY METHOD

24. DYEING OF COTTON WITH REACTIVE DYES WORLD FIBRE CONSUMPTION (X1000 tonne) Dye consumption (Tonne) 48500 20500 42% 2200 2400 23400 49% 2000 42600 17300 41% 2000 2500 20700 49% 1996 39300 14900 39% 2000 2700 18700 49% 1990 Total Synthetic wool Regenerated Cotton Year 354 000 290 000 300 000 Total 178 000 109 000 60 000 Reactive 13 000 18 000 28 000 Azoic 12 000 12 000 12 000 Indigo 22 000 21 000 36 000 Vat 68 000 60 000 74 000 Direct 70 000 70 000 90 000 Sulphur 2004 1995 1988 Dye class