Red benzothiazole monoazo dye for polyester fiber, mixed dye containing the same, and method of dyeing polyester fiber using the same

摘要

A monoazo dye for polyester fiber represented by formula ##STR1## and having a crystal modification characterized by an X-ray diffraction spectrum (CuK&agr;) showing a very strong peak at an angle of diffraction (2&thgr;) of about 14.2°, a strong peak at about 24.5. degree., and four weak peaks at about 16.9°, 23.6°, 25.3. degree., and 26.8°. The monoazo dye exhibits excellent dispersibility to effect level dyeing even under high temperature and severe conditions and provides a dyed material excellent in light fastness and rubbing fastness, as well as wet fastness after post-finish.