Strong-alkaline-resistant disperse blue dye, compounded mixture thereof, and preparation method thereof

The invention discloses a strong-alkaline-resistant disperse blue dye, a compounded mixture thereof, and a preparation method thereof. The strong-alkaline-resistant disperse blue dye is a compound represented as the structural formula (I), which is prepared by diazotizing 3-amino-5-nitrobenzoisothiazole with nitrosyl sulfuric acid and then performing a coupling reaction with a m/o-substituted-N-substituted aniline emulsion. The strong-alkaline-resistant disperse blue dye has green and environment-friendly production process. A test result proves that the dye can be used for dyeing hydrophobic fibers, such as Dacron, nylon, spandex and the like and blended fabrics thereof, can form bright gloss, and can replace disperse blue 165 and disperse blue 56. The disperse blue dye can be compounded with an azo-type disperse dye and an anthraquinone-type disperse dye in different ratios to regulate the tone of the dyes and improve effects, thereby satisfying demands under different application conditions. The dye has hi