Azo dyes corresponding to the formula (II): ##STR1## wherein G represents a group capable of forming a 5-membered chelate ring and R.sup.5 represents aryl or a thienyl group, combined with metal ions, in particular copper or nickel ions, to form stable azo dye-metal complexes which have advantageous spectral properties. They are therefore particularly suitable for the production of highly light-fast cyan images, e.g. by the Ink-Jet process, in which they may be used directly in the form of colored inks, or by the dye diffusion transfer process, in which they are released image-wise from corresponding dye-releasers in the course of development and transferred to a dye-absorbent layer.