Dyes: Production route
How azo chemistry builds colours molecule by molecule
What this tab covers How it is made: the main production routes or, for product families, the main product types and technologies, compared on share of supply, inputs per tonne, plant scale, yield, co-products and unit cost.Dyes are classed by how they attach to the fibre, which sets the chemistry and the intermediates. Most are azo dyes made by diazo coupling of aromatic amines; others are anthraquinones, phthalocyanines, indigoids and sulphur compounds. Production is batch fine chemistry: many small reactions, filtration, drying and blending. The costly parts are intermediates and effluent treatment. Chinese leaders (Zhejiang Longsheng, Runtu) are integrated back into intermediates, which lets them control the cycle; Indian makers are often strong in intermediates (H acid, vinyl sulphone) and reactive dyes.
Routes compared
| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| Disperse dyes (azo and anthraquinone) | China 460 kt output (2025) from 580 kt/yr capacity, 79% utilisation; most of world supply | aromatic amines, coupling components and about 30-50% dispersants by weight (indicative) | Longsheng 140 kt/yr, Runtu 110-118 kt/yr, Jihua 75-100 kt/yr in China (sources differ) | not published | acidic and coloured wastewater, spent acids | price RMB 18,000-22,000/t in 2025 (about $2,500-3,100/t) |
| Reactive dyes (vinyl sulphone and monochlorotriazine types) | China 308 kt output (2025) from about 455 kt/yr capacity, 68% utilisation; Indian industry claims over 40% of the world market (not verified) | H acid, vinyl sulphone ester, cyanuric chloride (indicative) | Huali 80 kt/yr, Runtu 80-100 kt/yr (sources differ), Longsheng 70 kt/yr; Annoqi 35 kt/yr; Kiri dyes JV 50 kt/yr | not published | H acid wastewater about 30 t per t; high salt loads in dyeing | price about RMB 22,000/t (2024), 21,000 (2025), 22,800 (H1 2026) |
| Vat and sulphur dyes (indigo, sulphur black) | a small share of tonnage; indigo dominant in denim (indicative) | aniline, sodium hydrosulphite or sodium sulphide (indicative) | single-product plants of 10-50 kt/yr (indicative) | not published | sulphide and sulphate-rich effluent | sulphur RMB 12,000-15,000/t; vat RMB 35,000-45,000/t |
| Acid, direct and basic dyes | acid dye consumption about 250 kt/yr | naphthalene sulphonic acids and aromatic amines (indicative) | multi-product batch plants | not published | coloured effluent; metal-complex dyes contain chromium or cobalt | acid RMB 35,000-40,000/t; direct RMB 8,000-12,000/t |
How each route works
Disperse dyes (azo and anthraquinone)Small, non-ionic molecules milled with dispersants to sub-micron particles; applied to polyester at about 130 C under pressure. Para-base ester and reduction products are key intermediates.
follows polyester growth; Chinese oligopoly sets prices
China Dyestuff Industry Association via broker report (Aug 2026); Faxian Gongchang 2026 Reactive dyes (vinyl sulphone and monochlorotriazine types)Azo, formazan or anthraquinone chromophores carrying a reactive group that forms a covalent bond with cellulose under alkali. H acid and vinyl sulphone are the main intermediates.
bright, fast colours on cotton; salt, alkali and unfixed dye in effluent
China Dyestuff Industry Association via broker report (Aug 2026); Faxian Gongchang 2026; Indian Chemical News Aug 2025; Kiri factsheet FY23 Vat and sulphur dyes (indigo, sulphur black)Insoluble dyes reduced to a soluble leuco form with sodium hydrosulphite or sulphide, absorbed by cotton, then re-oxidised. Indigo is made from aniline.
cheap dark shades and the denim look; heavy reducing-agent use
Faxian Gongchang 2026; DGTR sunset review of sodium hydrosulphite from China (Sep 2026) Acid, direct and basic dyesWater-soluble anionic (acid, direct) or cationic (basic) dyes for wool, nylon, leather, paper and acrylic fibre, applied without covalent bonding.
simple application; lower fastness for direct dyes
Faxian Gongchang 2026 Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.