Alkaline green is used in the dyeing of acrylic fibers, silk, wool, diacetate and cotton fibers. Dyeing of acrylic and diacetate fibers has better fastness to sunlight and other fastnesses (soaping, sweat stains, etc.). The fastness of dyed wool, silk, and cotton fibers is slightly worse. Can also be dyed leather, paper, hemp, bamboo, wood, etc., as well as the manufacture of color lake. After the acrylic fiber yarn after alkaline fuxing dyeing, black color can be obtained, and the fastness is improved. It is also a standard dye for determining the saturation value of acrylic fibers and the saturation coefficient of cationic dyestuff.