Indigo Blue Granular Company | High-Purity, Factory-Direct

Inside the Indigo Supply Chain: What Indigo Blue Granular Company Means for Modern Cotton Dyeing

If you spend your days thinking about vat blues (guilty as charged), you’ll quickly notice how the category has been quietly reshaped by better granulation, cleaner reduction profiles, and tighter QC. That’s where Indigo Blue Granular Company solutions—specifically Bromo Indigo (C.I. Vat Blue 5)—have been getting real traction with mills that need repeatable shades and fewer line stoppages.

Industry pulse

Three shifts are obvious: mills want lower dust loads, predictable leuco formation under hydrosulfite/alkali, and documentation that stands up to brand audits. In fact, denim and workwear labels now ask for test data up front. To be honest, a few years ago that was “nice to have.” Today, it’s table stakes.

What it is (and why it matters)

Product: Bromo Indigo; Vat Bromo-Indigo; C.I. Vat Blue 5 (CAS 2475-31-2), molecular formula C16H6Br4N2O2, HS 3204151000. Origin: HEBEI FUXIN INTERNATIONAL TRADE CO., LTD., A-1205, MCC World Grand Plaza, 66 Xiangtai Road, Shijiazhuang 050023, China. It’s mainly used on cotton fabrics, but I’ve seen mills deploy it in cotton-rich blends with careful process control.

Process flow (shop-floor version)

• Materials: Bromo Indigo granules, Na2S2O4 (hydrosulfite), NaOH, wetting agent, sequestrants.
• Reduction: 50–60°C, controlled pH 11–12.5; target clear leuco bath (ORP ≈ −700 mV, real-world may vary).
• Application: Dip-nip cycles for rope/slasher; pad-steam or jig for piece goods.
• Oxidation: Air or mild H2O2; then rinse, soap at 90–95°C for shade brightness.
• Testing: ISO 105-C06 washing, ISO 105-X12 rubbing (dry/wet), ISO 105-B02 lightfastness; AATCC 61/16 equivalent accepted by some buyers.
• Service life: Typical garments withstand 30–50 domestic washes with shade retention Grade 4–5; workwear targets higher, depending on finish.
• Industries: Denim, chinos, uniforms, home textiles (select lines).

Quick in-house data shared by mills (yes, I asked): Wash fastness 4–5; dry rub 4–5; wet rub 3–4; lightfastness 5–6. Your mileage will depend on liquor ratio, soaping discipline, and finishing—surprisingly, soaping is where many plants leave color on the table.

Advantages we keep hearing about

• Granular flowability reduces caking and dust (operators love this, to be honest).
• Consistent leuco formation → fewer shade corrections and reworks.
• Documentation: REACH-ready dossiers, OEKO-TEX support letters on request.

Vendor snapshot and comparison

Customization and real-world use

Shade tuning (slightly red or green cast), particle-size windows, and pre-dispersion aids are available. Mills tell me that small tweaks to hydrosulfite feed and nip pressure often beat fancy add-ons—simple, yes, but it works.

Case notes

• Denim rope line: −8% re-dye due to steadier leuco; wet rub improved from 3 to 3–4.
• Uniform fabric: Achieved ISO 105-C06 Grade 4–5 wash; 50-cycle target met.

Standards and references: ISO 105 series (C06, X12, B02); AATCC 61/16; REACH Annex XVII compliance for applicable substances; third-party audit on request.

Authoritative citations

1. ISO 105-C06: Textiles — Tests for colour fastness — Part C06: Colour fastness to domestic and commercial laundering
2. AATCC TM61: Colorfastness to Laundering, Accelerated
3. ECHA: Understanding REACH (European Chemicals Agency)