Dye mixtures containing one or more thienyl and/or thiazolazo dyes with a coupling component of the aminothiazol, anilin or tetrahydroquinoline series, one or more dyes from the class of monoazo or diazo, methine, azamethine, anthraquinone, nitro or quinophthalone dyes, the maximum absorption of which is at a wavelength of 410 to 520 nm, and possibly one or more dyes from the class of monoazo or diazo, methine, azamethine, anthraquinone, nitro or quinophthalone dyes, the maximum absorption of which is at a wavelength of 600 to 700 nm, where the half-width value of the maximum absorption is at least 2000 cm-1, a process for the thermal transfer of said dye mixtures and their use in dyeing or printing synthetic materials.