This standard specifies the requirements, sampling, test methods, inspection rules, signs, labels, packaging, transportation and storage of acid black NM-3BRL 140% products. This standard applies to the quality inspection of acid black NM-3BRL 140%. This product is mainly used for dyeing nylon, but can also be used for dyeing wool, silk, leather, etc. Structural formula: CHNOSNaCr Relative molecular mass: 970.73 (according to the 2001 international relative atomic mass)