Abstract: Azoxy dyes of the general formula I in the form of the free acid where n is 0 or 1, each R1 is selected from the group consisting of methoxy, hydroxyl and carboxyl, each R2 is selected from the group consisting of carboxyl, amino, C1-C4-alkylamino, allylamino, benzylamino and methoxycarbonylmethylamino, and the phenyl rings A may additionally be substituted by C1-C8-alkyl, unsubstituted or methyl- or halogen-substituted phenyl, hydroxyl, amino, nitro, halogen, carboxyl, N-benzylcarbamoyl, unsubstituted or nitro-, halogen-, C1-C4-alkoxy- or acetoxy-substituted phenylcarbamoyl and naphthylcarbamoyl or be benzofused, their copper complexes, a process for preparing the copper complex dyes, azoxy dyes of the formula I in their partially or completely deacylated form, their copper complexes, colorants comprising these azoxy dyes and/or their copper complexes and also their use for dyeing and printing natural or synthetic substrates.

Abstract: Azoxy dyes of the general formula I in the form of the free acid 1

Abstract: In a method of marking hydrocarbons by addition of at least one first marker, at least one second marker which cannot be removed completely from the hydrocarbons under the conditions of the removal of the first marker or markers is additionally added to the hydrocarbons.

Abstract: Azoxy dyes of the general formula I in the form of the free acid where n is 0 or 1, each R1 is selected from the group consisting of methoxy, hydroxyl and carboxyl, each R2 is selected from the group consisting of carboxyl, amino, C1-C4-alkylamino, allylamino, benzylamino and methoxycarbonylmethylamino, and the phenyl rings A may additionally be substituted by C1-C8-alkyl, unsubstituted or methyl- or halogen-substituted phenyl, hydroxyl, amino, nitro, halogen, carboxyl, N-benzylcarbamoyl, unsubstituted or nitro-, halogen-, C1-C4-alkoxy- or acetoxy-substituted phenylcarbamoyl and naphthylcarbamoyl or be benzofused, their copper complexes, a process for preparing the copper complex dyes, azoxy dyes of the formula I in their partially or completely deacylated form, their copper complexes, colorants comprising these azoxy dyes and/or their copper complexes and also their use for dyeing and printing natural or synthetic substrates.

Abstract: Compositions comprising as components A) at least one bisazo compound selected from the group consisting of the compounds of the general formula Ia  and of the general formula Ib  where R1 is C1-C8-alkyl, R2 is C2-C8-alkyl, R3 and R3′ are each C2-C21-alkyl in which up to four CH2 groups of the carbon chain may be replaced by oxygen in ether function, R4 is hydrogen or is R3 (independently of R3), R4′ is hydrogen or is R3′ (independently of R3′), B) at least one solvent in which said component A) is soluble, and optionally C) at least one surface-active substance, are useful as dye penetrants for detecting surface cracks or other defects in workpieces to be tested in this respect.

Abstract: Dye mixtures comprising one or more thienyl- and/or thiazole-azo dyes with a coupling component of the aminothiazole, aniline or tetrahydroquinoline series, one or more dyes of the class of the monoazo or disazo dyes, methine dyes, azamethine dyes, anthraquinone dyes, nitro dyes or quinophthalone dyes which have their respective absorption maximum at a wavelength of from 410 to 520 nm and optionally one or more dyes of the class of the monoazo or disazo dyes, methine dyes, azamethine dyes, anthraquinone dyes, nitro dyes or quinophthalone dyes which have their respective absorption maximum at a wavelength of from 600 to 700 nm, the FWHM value of the absorption maximum being at least 2000 cm−1, are useful for thermal transfer and for dyeing or printing synthetic materials.

Abstract: Azo dyes of the formula ##STR1## where the ring A may be benzofused,n is 0 or 1, and R.sup.1 -R.sup.8 are as defined,as pH-dependent markers for hydrocarbons, hydrocarbons containing the above-mentioned azo dyes, and a method for detecting these azo dyes in hydrocarbons.