Used as a dye in the textile industry for coloring synthetic fibers, especially acrylic and modacrylic fabrics. Provides a range of brown shades with good color fastness. Also applied in the dyeing of plastics and sometimes in printing inks where a brown hue is required. Its cationic nature allows it to bond effectively to negatively charged surfaces, making it suitable for materials with such properties. Limited use in cosmetics and hair dyes due to potential sensitization concerns.