Reactive Dyes
Reactive dyes are the only dye class that forms a permanent covalent bond with the fiber — the dye literally becomes part of the fabric. This chemical bond is what sets reactive dyes apart from all other dye types and gives them their most valued property: wash fastness of Grade 4-5 on cellulosic fibers.
INNO CHEM can supply following items meeting ZDHC,Bluesign,OEKO-TEX class|environmental standard.
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![Reactive Blue 19]()
Reactive Blue 19PRODUCT NAME: Reactive Blue 19
TYPE: Reactive Dyes Classic Series
CAS NO: 2580-78-1
MOQ: 25KG
PACKAGE: Carton -
![Reactive Yellow 160]()
Reactive Yellow 160PRODUCT NAME: Reactive Yellow 160
TYPE: Reactive Dyes Classic Series
CAS NO: 129898-77-7
MOQ: 25KG
PACKAGE: Carton -
![Reactive Black WNN]()
Reactive Black WNNPRODUCT NAME: Reactive Black WNN
TYPE: Reactive Dyes Classic Series
CAS NO: 17095-24-8
MOQ: 25KG
PACKAGE: Carton -
![Liquid Reactive Blue]()
Liquid Reactive BluePRODUCT NAME: Liquid Reactive Blue
TYPE: Liquid Reactive Dyes
CAS NO: 12236-92-9
MOQ: 25KG
PACKAGE: Drum
Key Properties
1.Wash fastness: Grade 4-5 (excellent, due to covalent bonding);
2.Light fastness: Grade 6 (good UV resistance);
3.Bright shades: Superior chromaticity compared to direct and sulfur dyes;
4.Full solubility: Water-soluble due to sulfonate groups;
5.Versatile application: Suitable for exhaust, pad, and printing methods.
Application
Cotton fabric dyeing — apparel, home textiles, garments
Rayon and viscose — regenerated cellulose fibers
Linen and flax — natural cellulosic fibers
Wool and silk — protein fiber applications
Textile printing — discharge and direct printing
Yarn dyeing — package dyeing, hank dyeing
FAQ
Q: Why does reactive dyeing require salt?
A: Cotton fibers carry a negative surface charge in water, which repels the negatively charged dye molecules. Adding electrolyte (sodium chloride or sodium sulfate, typically 20-80 g/L) neutralizes this surface charge, allowing dye molecules to approach and adsorb onto the fiber. Without sufficient salt, dye exhaustion drops significantly, leading to poor color yield and wasted dye.
Q: What is reactive dye hydrolysis and how does it affect dyeing?
A: Hydrolysis is the most significant technical challenge in reactive dyeing. In the alkaline dye bath, hydroxide ions (OH⁻) compete with fiber hydroxyl groups to react with the dye's reactive group, forming hydrolyzed dye that cannot bond with the fiber. This side reaction reduces fixation efficiency by 10-30% in typical commercial operations. Proper alkali control and timely dyeing minimize hydrolysis losses.
Q: Can reactive dyes be stripped from fabric if the shade is wrong?
A: Reactive dyes cannot be fully stripped once the covalent bond has formed — the bond is permanent. Only partial stripping is possible using dilute acid (glacial acetic acid 5-10 mL/L or formic acid 2.5-10 mL/L at 70-100°C), which breaks some dye-fiber bonds. This means careful color matching and process control before bulk dyeing is essential to avoid costly corrections.
Q: What is the fixation rate of reactive dyes?
A: Typical fixation rates range from 50-80%, depending on dye type and process conditions. Bifunctional reactive dyes (with two reactive groups) achieve higher fixation than monofunctional types. The remaining 20-50% becomes hydrolyzed dye that must be washed off. Optimizing salt concentration, alkali dosage, temperature, and timing helps maximize fixation efficiency.
As one of the most professional reactive dyes manufacturers and suppliers in China, we offer a wide range of products with superior quality. Please feel free to buy high-grade reactive dyes made in China here from our factory. For price consultation, contact us.
