Production of copper complex compounds of o.o'-dihydroxyazo dyestuffs

Claim 1

A PROCESS FOR THE PRODUCTION OF STABLE COPPER COMPLEX COMPOUNDS OF BIS-(O,O''-DIHYDROXY AZO) DYESTUFFS WHICH COMPRISES ADDING AN AQUEOUS SOLUTION OF HYDROGEN PEROXIDE AT TEMPERATURE BETWEEN 20 AND 80* C. TO A WEAKLY ACID MIXTURE OF AN AQUEOUS SOLUTION OF AT LEAST AN EQUIVALENT AMOUNT, WITH REFERENCE TO ONE AZO GROUP, OF A COPPER SALT AND OF A BIS-(MONO-HYDROXY AZO) DYESTUFF DERIVED FROM ONE MOLECULE OF A TETRAZOTIZED DIAMINE SELECTED FROM THE CLASS CONSISTING OF BENZIDINE AND 1.4-DIAMINO-BENZENE HAVING UNSUBSTITUTED ORTHO POSITIONS TO THE DIAZO GROUPS, AND TWO MOLECULES OF A NAPHTHOL SULFONIC ACID WHICH COUPLES IN ALKALINE SOLUTION IN ORTHO POSITION TO THE HYDROXYL GROUP.