| Name | Sulphur Blue CV |
| Synonyms | Sulphur Blue CV Sulfur Sky Blue CV C.I.Sulphur Blue 15 Asathio Light Green BG Dycosulphur Sky Blue CV |
| Physical and Chemical Properties | Chemical properties blue-gray powder. Slightly soluble in water. It is olive-colored when dissolved in sodium sulfide solution. It is dark blue in concentrated sulfuric acid, and dark blue precipitate is produced after dilution. The alkaline hydrosulfite solution is dark yellow and returns to normal color light after oxidation. |
| Use | 1, sulfide blue CV is mainly used for cotton, hemp, viscose fiber and its fabric dyeing. Commonly used in the combination of crab, dark green, blue, blue-green and other colors. 2, mainly used for cotton, hemp textile dyeing |
Using p-aminophenol and mixed Cliff acid [5-(and 8-) amino -2-naphthalene sulfonic acid, that is, 1,6-Cliff acid and 1,7-Cliff acid] as raw materials, First, the two are condensed in the presence of sodium hypochlorite at -2-0°C, the intermediate 5-(and 8-) amino -8-(and 5-)(p-hydroxyanilinyl)-2-naphthalenesulfonic acid was obtained, and then vulcanized with sodium polysulfide aqueous solution at 108°C (about reflux 24h). After vulcanization, air is introduced at 50 ℃ for oxidation, pH = 7 with acid can be filtered, and the finished product can be dried and crushed.