Used as a dye in various industries, particularly for coloring paper, leather, and textiles. It is also employed in biological staining to enhance the visibility of microscopic structures. In the ink industry, it serves as a key component for producing blue-black inks. Additionally, it finds application in the manufacture of polishes and coatings, providing a deep, consistent color. Its water-soluble nature makes it easy to incorporate into aqueous solutions for diverse industrial processes.