PCT No. PCT/EP98/01325 Sec. 371 Date Sep. 17, 1999 Sec. 102(e) Date Sep. 17, 1999 PCT Filed Mar. 6, 1998 PCT Pub. No. WO98/41581 PCT Pub. Date Sep. 24, 1998Oligomeric azo dyes having an alternating construction made up of diazo components and coupling components, containing in the molecule at least 3 units of the structure I-[D-K]-(I)where D is a tetrazo component of the formula II where x is a direct bond, oxygen, sulfur or a bridge member of the formula -NHCO-, -NHCONH-, -CO-, -NHSO2-, -SO2NHSO2-, -SO2-, -SO2-NH-A-NH-SO2-, -NAlk-CO-, -NAlk-CO-NAlk-, -NAlk-CO-NH-, -NAlk-SO2-, -SO2-NAlk-SO2-, -SO2-NAlk-A-NAlk-SO2-, -SO2-NAlk-A-NH-SO2-, -CH=CH-, -CH2CH2-, -C(CH3)2-, -CH2- or -NH-, R1 and R2 are each independently of the other hydrogen, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkanoyl, cyano, carboxyl, hydroxysulfonyl, C1-C4-alkoxycarbonyl, hydroxyl, carbamoyl, mono- or di-(C1-C4)-alkyl-carbamoyl, sulfamoyl, mono- or di-(C1-C4)-alkyl-sulfamoyl, fluorine, chlorine, bromine, nitro or trifluoromethyl and R3 and R4 are each independently of the other hydrogen, hydroxysulfonyl or carboxyl, and where K is a coupling component III of the aminonaphthol series, it being possible for up to 90 mol % of component III to be replaced by a coupling component IV, are prepared and used for dyeing natural or synthetic substrates.
