Used primarily as a dye in the textile industry for dyeing cotton, linen, and other cellulosic fibers, providing a bright blue color. Suitable for dyeing in mild to medium alkaline conditions, offering uniform coloration and moderate wash fastness. Commonly applied in continuous or batch dyeing processes and in the printing of fabrics. Also used in the paper industry for coloring paper products and in leather dyeing. Utilized in biological staining for microscopy to enhance contrast in cell and tissue samples. Limited use in some industrial tracers due to its strong color and water solubility. However, it has limitations in light fastness and resistance to bleaching agents, making it unsuitable for products exposed to prolonged sunlight.