Naphthol as Azoic Coupling Component 2 Naphthol Dye for Textile

Naphthol AS (C.I. 37505 / Azoic Coupling Component 2) is the most basic and widely used member of the Naphthol AS series. It has low affinity to cotton and medium coupling ability. Unlike Naphthol AS-BO which is a high substantivity naphthol, Naphthol AS serves as the standard reference for the entire series. It produces bright red shades when combined with Fast Red G base.

Main applications include cotton fiber dyeing and printing, viscose, vinylon, silk, and diacetate fiber dyeing. It is used as a primer for cotton dyeing and printing, and for discharge printing of cotton fabrics. It is also used for producing organic pigments.

Naphthol AS is a key intermediate for synthesizing a wide range of organic pigments, including Pigment Orange 24, Pigment Red 2, Pigment Red 21, Pigment Red 22, Pigment Red 32, Pigment Red 245, Pigment Red 258, Pigment Red 268, Pigment Violet 13, Pigment Violet 17, Pigment Violet 50, and Pigment Blue 20.

When dyeing cotton, Naphthol AS has low affinity to cotton and medium coupling ability. The coupling pH value is determined by the diazo component of ice dyeing. It is commonly used with Fast Red G base to produce bright red shades. It can also be printed with reactive dyes and used for discharge printing and background color anti-dye printing of reactive dyes.

Naphthol AS is produced by the condensation of aniline with 2,3-acid (3-hydroxy-2-naphthoic acid). The product is then processed into a beige powder with a minimum purity of 99% and a melting point of 246-248 degrees C. Standard packaging is 25kg cartons.