| Physical and Chemical Properties | Black powder. Solubility in water (50 °c) was 10g/L. The aqueous solution is cyan black, and the color is unchanged by adding 1mol/L sodium hydroxide, followed by addition of sodium hydrosulfite and warming, the solution is light yellow, and the color remains unchanged by adding sodium perborate. Purple in concentrated sulfuric acid, diluted with water, color unchanged; Purple-black in concentrated nitric acid, diluted with water to turn cyan. |
| Use | reactive black K-BR can be used for dyeing cotton and viscose fibers with good fastness, it is usually used only for dyeing gray or toning light. It can also be combined with active brilliant orange K-G, active brilliant blue Brown, and active brilliant orange K-R Gray. It can also be used for direct printing of silk and cotton blended fabrics, two bath dyeing of polyester/cotton blended fabrics, etc. |
| production method | with 2-hydroxy-5-nitroaniline, H acid, cyanuric chloride and chromium sulfate, Cobalt sulfate as raw materials, first, 2-hydroxy-5-nitroaniline was diazotized and coupled with H acid, and then the coupled product was sequentially reacted with chromium sulfate and cobalt sulfate in the presence of sodium acetate to form a mixed metal complex dye precursor. The cyanuric chloride is subsequently condensed with the metal complex dye precursor and the product is obtained by a second condensation with aqueous ammonia. After salting out, filtration, drying to obtain the finished product.. |