| Physical and Chemical Properties | Chemical properties dark blue powder. Insoluble in water, insoluble in sodium sulfide solution. It is yellow in the alkaline reduction solution; it is dark green and yellow in the acidic reduction solution. It is green and blue in concentrated sulfuric acid, and green and blue precipitate is produced after dilution. |
| Use | Uses vulcanized reduction blue GNX is mainly used for dyeing cotton, hemp, viscose fiber and cotton blended fabric, and also used for dyeing all kinds of blue, with slightly blue-green color. |
| Raw Materials | FUMING SULFURIC ACID SODIUM TETRASULFIDE 4-Nitrosophenol N-Ethylcarbazole 4-[(9-ethyl-9H-carbazol-3-yl)amino]phenol C.I.Vatblue43 4-Nitrosophenol |
| EPA chemical information | C. I. Vat Blue 42 (1327-81-7) |
Using 9-ethylcarbazole and p-nitroso phenol as raw materials, the two are first condensed in the presence of concentrated sulfuric acid at -23°C, reduced, and then refluxed with sodium polysulfide in butanol medium, After the butanol is evaporated, the finished product is oxidized, filtered, dried, and crushed..
0.4mol of ethyl carbazole and 325mL of concentrated sulfuric acid were melted to obtain ethyl carbazole sulfate at 70 ℃. Dissolve 0.41mol p-nitroso phenol and 325mL concentrated sulfuric acid at 10 ℃ to obtain nitrosyl sulfuric acid solution.
Ethylcarbazole sulfate and nitrosol sulfuric acid solution were reduced at -20 ℃ for 6h, the iron slag was removed by filtration, and the reduced leuco (I) was obtained by drying.
Heat 200mL of butanol, sodium sulfide, sulfur and leuco (I) together to 110 ℃ for 24h, then add 4g of sodium nitrite (95%), and continue to reflux for 2h. Steam butanol, desulfurize, oxidize with air, and dry the product.