C.I.Direct Blue 15
C.I.24400
CAS:2429-74-5

Synonymous names:Apollo Direct Sky Blue 5B (THC);Atul Direct Sky Blue (AP);Direct Fast Blue 5B (WUXI);Direct Sky Blue 5B (STIE,NIEC,HEB,NJC);Dycosdirect Sky Blue 5B (SHC);Everdirect Sky Blue 5B (ECI);Everlan Blue 5B (ECI);Kayafect Blue C (KYK);Kayaku Direct Sky Blue 5B (KYK);Levacell Blue S (DYS);Nippon Kagaku Direct Paper Sky Blue 5BL (KKK);Tertrodirect Blue FF NEW (CKC)

Physicochemical Properties: Blue powder. Highly soluble in water, yielding a reddish-blue solution with a solubility of 60 g/L (85°C). Insoluble in organic solvents. In concentrated sulfuric acid, it appears bluish-green, turning to reddish-blue upon dilution. In concentrated nitric acid, it forms a reddish-gray solution. The aqueous dye solution turns reddish-blue with concentrated hydrochloric acid and purple with concentrated sodium hydroxide, both with precipitation.

Applications: Mainly used for dyeing cotton, viscose, and other cellulose fabrics, offering excellent dye uptake but poor migration and leveling. Staged salt addition is recommended for controlled dyeing. Suitable for direct printing and discharge printing on cotton and viscose fabrics. Can be combined with Direct Green B, Direct Claret GB, Direct Deep Brown M, and Direct Copper Blue 2R for shading. Also used for dyeing silk and viscose/nylon blends, with good discharge effects on silk. Additionally used for coloring paper, biological specimens, and film, as well as ink preparation.