How to Use Azo Dyes to Label Hydrocarbons and Azo Dyes

摘要

The present invention relates to a method of using the azo dye of the following general formula (1), a method of detecting such azo dye in hydrocarbon, and a new azo dye.;Wherein ring A may be benzofused and n is 0 or 1, R ¹ is C ₁ -C ₁₅ -alkyl or hydrogen, which may be interrupted by 1 to 4 ether oxygen atoms, and R ² is 1 to C ₁ -C ₁₅ -alkyl which may be interrupted by four ether oxygen atoms, or the general formula L-NX ¹ X ² (L is C ₂ -C ₈ -alkylene, X ¹ and X ² are each independently Is a C ₁ -C ₆ -alkyl or, together with the nitrogen atom connecting them, is a radical of a 5- or 6-membered saturated heterocyclic radical which may further contain an oxygen atom in the ring), R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ are independently hydrogen, C ₁ -C ₁₅ -alkyl or C ₁ -C ₁₅ -alkoxy group, R ⁸ is hydrogen, C ₁ -C ₁₅ -alkyl, C ₁ -C ₁₅ -alkoxy, cyano, nitro or a radical of the formula COOX ³ (X ³ is hydrogen, C ₁ -C ₁₅ -alkyl which may be interrupted by 1 to 4 ether oxygen atoms) or a general formula L- NX ¹ X ² (L, X ¹ and X ² are as defined above).