1. Sulfur dyes are insoluble in water and need to be reduced by alkali sulfide to generate leuco body to dissolve. Sulfur dye leuco cellulose fiber has affinity. After dyeing, it is oxidized to regenerate insoluble dye on the fabric and fix it.
2. Easy to manufacture, low price, high washing fastness, light fastness varies with varieties, commonly used vulcanized black can reach 6-7 grades, vulcanized blue reaches 5-6 grades, brown, orange, Yellow is generally 3-4 levels.
3. The chromatogram is not complete, the color is not bright enough, most sulfur dyes are not resistant to chlorine bleaching, and some varieties have storage brittleness. Among them, the storage brittleness of sulfide black dyes is more serious.