| Molecular Formula | C40H23N7Na4O13S4 |
| Molar Mass | 1029.8688 |
| Physical and Chemical Properties | Chemical properties gray-black powder. Easily soluble in water, the aqueous solution is blue-purple, adding concentrated hydrochloric acid to produce dark blue precipitate; adding concentrated sodium hydroxide solution to produce blue-purple precipitate. Insoluble in ethanol. It is green and gray-blue in concentrated sulfuric acid, and turns purple after dilution. |
| Use | Use direct sunscreen 2BL is mainly used for dyeing cotton, viscose fiber and its fabrics, and can also be used for dyeing silk and wool/viscose blended fabrics. Good levelness. No response to copper and iron ions, not sensitive to hard water. |
| Raw Materials | Sodium hydroxide 1-Naphthylamine 2-Amino-4,8-naphthalenedisulfonic acid INDUSTRIAL SALT Iodic acid |
It is diazotized by amino C acid, and then coupled with methylnaphthylamine. The primary coupling is subjected to secondary diazotization, and then coupled with 1, 7-aminonaphthalene sulfonic acid (cliffic acid). The secondary azo is diazotized again, and then combined with & gamma; acid for the third time, and finally salted out, filtered and dried.