摘要 |
Novel disazo colorants or dyes for marking organic liquids, the colorants having the general formula WHERE R1 is H, CF3, or alkyl having from 1 to 4 carbon atoms, R2 is H, or alkyl having from 1 to 4 carbon atoms, R3 and R4 are each H, OCH3, OC2H5 or CH3, and R5, R6 and R7 are each H, or alkyl having from 1 to 12 carbon atoms, at least one of said R5, R6 and R7 being alkyl. |