abstract |
Amino azoic dyes having general formula (I) wherein: R1 is linear or branched alkyl having from 4 to 20 carbon atoms; R?2 and R3¿ are independently H, CH¿3?, C2H5, OCH3, OC2H5; R?4 and R5¿ are independently H, CH¿3?, C2H5; X IS H, OH; Y is hydrogen or poly-isopropoxy chain (IA) wherein n is comprised between 1 and 4; they are used as markers of oil distillation product. |