Sulfur Dye


Also found in: Wikipedia.

sulfur dye

[′səl·fər ‚dī]
(organic chemistry)

Sulfur Dye

 

any of the organic dyes that are high-molecular-weight compounds containing the heterocycles

and the groups SH and Sn, where n ≥ 2 (the precise chemical structure has not been established). Sulfur dyes are amorphous substances, insoluble in water and most organic solvents; when acted upon by Na2 S, they form water-soluble leuco compounds according to the scheme

After imparting color, these compounds are oxidized by oxygen in the air and are reconverted on the fiber to insoluble sulfur dyes.

Sulfur dyes are obtained by a prolonged heating of such organic compounds as aromatic amino, nitro, amino-hydroxy, and nitro-hydroxy compounds and heterocyclic azines with sulfur or a polysulfide of sodium (Na2 Sn’n = 2–9).

Sulfur dyes are usually pale. The black, blue, brown, and green dyes have the greatest importance; the yellow and orange dyes have only limited use. Red sulfur dyes are unknown. While the black dyes are fast, the other sulfur dyes impart colors of lesser permanence. Sulfur dyes are inexpensive and convenient. They are widely used for dyeing cotton fabric; in the textile industry, however, they have been partially replaced by vat dyes and reaction dyes, which offer brighter and more permanent colors.

REFERENCCE

Chekalin, M. A., B. V. Passet, and B. A. Ioffe. Tekhnologiia organiches-kikh krasiteleii promezhulochnykh produktov. Leningrad, 1972.

M. A. Chekalin

References in periodicals archive ?
The market has also been segmented on the basis of product types--dyes (reactive dye, disperse dye, sulfur dye, VAT dye, acid dye, direct dye, basic dye, and others), organic pigments (azo, phthalocyanines blues and greens, and high performance pigments), and inorganic pigments (titanium dioxide, iron oxide, and others).
The market has also been segmented on the basis of product types - dyes (reactive dye, disperse dye, sulfur dye, VAT dye, acid dye, direct dye, basic dye, and others), organic pigments (azo, phthalocyanines blues and greens, and high performance pigments), and inorganic pigments (titanium dioxide, iron oxide, and others).
For instance, our EarthColors sulfur dyes are developed from natural waste such as walnut and almond husks and agricultural crop waste, replacing the oil-based raw materials to create warm shades of brown on cotton fabrics.
They have the overall performance of the company's existing range of sulfur dyes made from conventional raw materials.
The new dyes which Archroma describes as biosynthetic sulfur dyes have been four years in the making.
Some of these dyes are- Acid (Anionic) dyes, Basic (Cationic) dyes, Neutral - Premetalized dyes, sulfur dyes, vat dyes, reactive dyes, pigment dyes, etc.
In combination with the company's full range of Diresul(r) RDT sulfur dyes, including cutting-edge non-indigo based Diresul(r) RDT Indicolors dyes, Advanced Denim offers unique effects, improved fastness, better reproducibility of tones and shades, and easy application for more precise results.