Mainly uses in cellulose textile fibers and so on cotton and kapok, hemp, viscose weave with the dyeing, may also use in the silk, the polyamide fiber and the blend fabric dyeing, but may also use in the leather, biological and the lumber dyeing, the plastic coloration and takes the red ink raw material and so on. Direct black bN is the commonly used black dye, many uses in the black alone, also often puts together Cheng Gezhong with the brown the coffee color.