Widely used in the fuel industry as a dye to color diesel and heating oils, aiding in differentiation from other fuel types. Helps authorities and consumers identify fuel intended for specific uses, especially in detecting tax evasion or misuse of subsidized fuels. Also applied in solvent-based systems where clear identification of liquid products is required. Its strong tinting strength and solubility in non-polar media make it suitable for marking and tracing applications in oils and organic solvents.