Basic Introduction To Sulfur Dyes

Sulfur dyes have been around for more than a hundred years, and the first sulfur dye was made in 1873 by Croissant and Bretonniere, who heated materials containing organic fibers, such as wood chip humus, bran, waste cotton and waste paper, with sulfide alkali and polysulfide alkali. This dark hygroscopic dye with foul odor, the composition is not fixed and soluble in water, and green dye is obtained when dyeing cotton in two baths, alkaline bath and sulfide alkali bath. When exposed to air or fixed by chemical oxidation of dichromate solutions, cotton cloth can become brown. Because these dyes have excellent dyeing properties and low price, they can be used in the cotton dyeing industry.