Vat Dye Blue 4 (Indanthrone)
CAS Number: 81-77-6
Vat Dye Blue 4, chemically known as Indanthrone, is the benchmark vat dye for cotton delivering deep navy-blue shades with the highest known light and wash fastness ratings. Applied via sodium dithionite/caustic soda reduction, it forms an insoluble colored pigment within the fiber on re-oxidation. Preferred in workwear, military uniform, and high-end denim dyeing.
Technical Specifications
| appearance | Dark blue powder |
| moisture (%) | ≤2 |
| strength (%) | 100±2 |
| wash fastness | ≥5 (ISO 105-C06) |
| light fastness | ≥8 (ISO 105-B02) |
| active content (%) | ≥96 |
Applications
- Exhaust vat dyeing of cotton workwear and military uniforms
- Continuous pad-steam vat dyeing of woven cotton fabric
- High-end denim indigo-style dyeing for fashion
- Dyeing of cotton-polyester blends for dark navy shades
- Dyeing of cotton yarn for color-woven fabrics requiring high fastness
Key Features
- Maximum light fastness rating 8 (ISO 105-B02), unsurpassed by any dye class
- Outstanding wash and wet fastness ≥5 for demanding end uses
- Suitable for both exhaust and continuous pad-steam processes
- Excellent chlorine bleach resistance for industrial laundering
Send Inquiry
CAS Number
81-77-6
Category
Textile Dyeing AuxiliariesAvailability
In StockSample
Dispatched within 5 days
More in Textile Dyeing Auxiliaries
Acid Dye Blue 25
6408-78-2
Acid Dye Red 18
2611-82-7
Amino Silicone Fabric Softener
106842-44-8
Ammonium Sulfate (pH Buffer for Reactive Dyeing)
7783-20-2
Anionic Leveling Agent for Cotton
68891-38-3
Anti-Reducing Agent for Printing (Sodium m-Nitrobenzenesulfonate)
Antistatic Agent for Textile (GMS Based)
4292-10-8
Bioscouring Enzyme (Pectinase) for Cotton