Sardacid™Acid Dyes
Water-soluble anionic dyes delivering brilliant, permanent colour on wool, silk, nylon, leather and feathers — with zero restricted aromatic amines.
Compatible Substrates
Water-Soluble Anionic Dyes for Protein Fibres
Acid Dyes are water-soluble anionic colourants applied to protein fibres (wool, silk), polyamide fibres (nylon), leather and feathers from a neutral to acidic dyebath. The dye–fibre bond is formed through ionic attraction between the anionic sulphonate groups on the dye and the cationic amino groups on the fibre.
The Sardar Chemical Acid Dye range — marketed under the Sardacid™ brand — offers a full colour gamut from pale pastels to deep, rich shades. All products are rigorously tested for Azo-free compliance and carry full certification for export markets under EU REACH regulations.
The range is particularly valued by Pakistan's tanneries for leather dyeing destined for export, where strict chemical compliance is a commercial requirement for buyers in the EU and UK.
ISO 14362 Tested
Every batch tested for restricted aromatic amines before dispatch. Certificates available for export shipments.
Fastness Ratings
Sardacid™ — Typical Fastness Grades
Blue Wool scale 1–8
Grades per ISO 105 series. Values are indicative — actual results depend on substrate, shade depth and process parameters.
Technical Properties
Standard Exhaust Dyeing Process
Dissolve the Dye
Dissolve the required quantity of acid dye in hot water (80–90 °C) with gentle stirring. Ensure complete dissolution before adding to the dyebath.
Prepare the Dyebath
Fill dyebath at 40–50 °C. Add ammonium sulphate or acetic acid to reach the target pH of 4.0–6.0.
Enter Substrate
Enter pre-wetted substrate (wool, silk, nylon or leather) at 40 °C. Agitate gently to ensure even wetting.
Add Dissolved Dye
Add the dissolved dye solution gradually over the running bath. Maintain uniform distribution through continuous agitation.
Raise Temperature
Raise temperature gradually (1–2 °C per minute) to 95–100 °C. Hold at boil for 30–60 minutes depending on shade depth.
Cool & Rinse
Cool to 60 °C, drain. Rinse thoroughly in warm then cold water. A neutralising ammonia rinse may be applied if required.
Sardacid™ Colour Range
Full technical data sheets and physical shade cards available on request. Contact our sales team.
Why Azo-Free Matters for Your Business
Our Acid Dyes are certified free of restricted aromatic amines — the chemical group that has made conventional azo dyes a compliance liability for exporters. Here's what that means for your factory and your customers.
The Chemistry
carcinogenic amines
Safe for humans & export
Azo dyes that release restricted aromatic amines under reductive conditions are banned under EU REACH Annex XVII and equivalent regulations in 30+ countries. Our dye chemistry uses safe chromophore structures — zero restricted amines.
Carcinogenic Amines
Azo dyes containing aromatic amines can cleave to release carcinogenic compounds that penetrate skin and are linked to bladder cancer.
Genotoxic Activity
Several restricted amines exhibit mutagenic and genotoxic activity, damaging DNA in human cells with prolonged skin contact.
30+ Country Ban
Over 30 countries and major trading blocs have banned textiles and leather goods containing restricted azo dyes since the 1990s.
Sardar's Solution
Every dye in our portfolio is rigorously tested — zero restricted aromatic amines. Our customers export to EU, US and Japan with confidence.
Restricted Aromatic Amines (Sample)
Per EU REACH Annex XVII, Appendix 8 — 24 amines restricted in dyes
Export to 30+ Markets with Confidence
Our Azo-Free certification satisfies regulatory requirements across all major export markets
Our 4-Stage Testing Protocol
Every batch of Acid Dyes passes through rigorous quality control before leaving our factory in Gadoon Amazai, Swabi.
Raw Material Screening
All incoming dye intermediates are screened by HPLC before production begins.
In-Process Control
Samples drawn at each reaction stage are tested for amine content.
Finished Goods Testing
Every batch is tested per EN ISO 14362 / EN ISO 17234 protocols before dispatch.
Third-Party Certification
Independent laboratory testing certificates available on request for export shipments.
Frequently Asked Questions
What fibres can Sardacid™ Acid Dyes be used on?
Sardacid™ Acid Dyes are suitable for protein and polyamide fibres: wool, silk, nylon 6 & 6,6, leather, feathers and modified acrylic (cationic-dyeable acrylic). They are not suitable for cotton or other cellulosic fibres without pre-treatment.
Are Sardar Chemical's Acid Dyes EU REACH compliant?
Yes. All Sardacid™ dyes are certified Azo-free — free of restricted aromatic amines listed under EU REACH Annex XVII (Appendix 8). Test certificates are available on request for export shipments to EU, UK, US and other regulated markets.
What is the typical dyebath pH for Acid Dyes?
Acid dyes are applied from a neutral to weakly acidic dyebath at pH 3.5–6.5. Ammonium sulphate or acetic acid is used to achieve the target pH. Application temperature is 95–100°C with 30–60 minutes at boil depending on shade depth.
What wash fastness rating do Sardacid™ dyes achieve?
Sardacid™ Acid Dyes achieve wash fastness of Grade 3–4 (ISO 105-C06), light fastness 4–6 (ISO 105-B02), and rubbing fastness 3–4 dry / 2–3 wet (ISO 105-X12). Actual values depend on the specific shade and substrate.
How do I order Sardacid™ Acid Dyes from Sardar Chemical?
Contact Sardar Chemical Industries Limited at [email protected] or call +92-42-35711154. We supply to textile mills, tanneries and dye houses across Pakistan and export to Bangladesh and other countries. Minimum order quantities and technical data sheets are available on request.