Textile auxiliaries are the process chemicals a mill uses alongside dyes. They help fabric wet out, take dye evenly, hold its colour and finish with the right handle.
Most are surfactant-based blends or polymers. Gujarat is a large producer because it sits next to the state's large textile industry and the dye plants of Vapi and Ankleshwar.
Auxiliaries by process stage
- Pretreatment products include wetting agents, scouring agents, desizing enzymes, sequestering agents and peroxide stabilisers for bleaching.
- Dyeing products include levelling agents, dispersing agents, anti-creasing agents and pH buffers that help dye go on evenly.
- After-treatment products include soaping agents that remove loose dye and fixing agents that improve wash fastness.
- Printing products include thickeners, binders for pigment printing and anti-migration agents.
- Finishing products include softeners, silicone emulsions, water and oil repellents, and anti-pilling or wrinkle-resistant finishes.
Why buyers find them hard to compare
Two auxiliaries sold as "levelling agent" may have different chemistry and very different results. Trade names reveal little, and suppliers rarely disclose full formulas. A certificate of analysis usually shows only solids, pH, ionic nature and appearance.
The real test is performance in your process. Run a lab trial on your own fabric, dye and water, with the current product as the control. Our guide to testing a specialty chemical's performance sets out how.
Compliance points
Many brands and retailers apply a manufacturing restricted-substance list to the chemicals their mills use. These lists commonly limit alkylphenol ethoxylates, some fluorinated repellents, formaldehyde and certain heavy metals.
Ask the supplier for a written declaration against the list your customer uses, and a recent test report where one exists. Confirm the current list version with your customer, because lists are updated regularly.
Concentration and dosing
Auxiliaries are sold at very different strengths. One softener may be 20% solids and another 60%. A cheaper drum of a weak product can cost more per kilogram of fabric treated. Compare products on the dose your mill needs, in grams per litre or as a percentage on the weight of fabric, not on the drum alone.
Ask each supplier for a recommended dose and the conditions it assumes, such as temperature, pH and liquor ratio. Then test at that dose and at your current dose. If a product only works at twice the stated dose, the data sheet was not written for your process.
Record the dose that works in your purchase specification, so that every later batch can be checked against it.
Also record the water hardness and fabric type used in the trial. If your mills change either, repeat a short trial before you change the dose.
Next step
We find auxiliary makers that formulate in-house, check samples against your process, and have lots tested before shipment. To match the products you use today, book a free sourcing review.