Verfahren zur Herstellung von neuen metallisierten Farbstoffen

摘要

The invention comprisds metallized dyes derived from a monoaxoic compound of the formula wherein R is an alkyl radical having 1 to 4 carbon atoms. The metallized dyes may be prepared by treating the corresponding metal free dye with a metallizing agent, e.g. cobalt sulphate, chloride or acetate, in the presence of a mixture comprising urea and dimethyl formamide or ethylene glycol preferably in the anhydrous state and at a temperature from 100 DEG to 140 DEG C. Alternatively the metallization can be carried out in aqueous phase in the presence of a cobalt salt or complexes of organic hydroxy acids. The examples relate to the preparation of cobalt and chromium complexes of dyes of the above formula in which R is an ethyl radical.