Sulfur Black :C.I.sulfur Black 1 CAS.1326-82-5

Sulfur Black (C.I. Sulfur Black 1) is the most important and widely used sulfur dye, accounting for approximately 75–85% of global sulfur dye production. It appears as a black powder or flake solid, insoluble in water but soluble in sodium sulfide solution, where it produces a greenish-black color.

1. Reduction: The dye is reduced using sodium sulfide to form a water-soluble leuco form

2. Dyeing: The leuco form is absorbed by cotton or other cellulosic fibers

3. Oxidation: The dyed fabric is exposed to air or oxidizing agents, restoring the insoluble dye and revealing the final black color

The most significant drawback of Sulfur Black is fiber tendering (strength loss). Residual sulfur compounds remaining in the dyed fabric slowly oxidize over time to form sulfuric acid, which degrades and weakens cellulose fibers. To prevent this, dyed fabrics must be:

· Treated with anti-tendering agents such as urea or sodium acetate

Traditional Sulfur Black dyeing requires excess sodium sulfide, generating wastewater with high sulfur content that is difficult to treat and may release toxic hydrogen sulfide gas. While the dye itself is considered non-toxic to humans, its production and use raise significant environmental concerns.

To address these issues, pre-reduced liquid Sulfur Black has been developed. This form:

· Improves rubbing fastness by approximately 0.5 grade

Liquid Sulfur Black is now widely adopted for denim yarn, knitted fabric, and package dyeing in many industrial countries.

Sulfur Black is primarily used for dyeing cotton textiles, as well as linen, viscose, and blended fabrics. It is also applied in leather and paper dyeing, where deep black shades are required at low cost.

Népszerű tags: sulfur black :c.i.sulfur black 1 cas.1326-82-5, China sulfur black :c.i.sulfur black 1 cas.1326-82-5 manufacturers, suppliers, factory, kénfestékek, kénfestékek a szálakhoz, kénfestékek finom szálakhoz, kénfestékek újrahasznosított szálakhoz, kénfestékek speciális szálakhoz, kénfestékek vízálló szálakhoz