Naphthol AS-PH Azoic Coupling Component 14 Naphthol Dye for Textile

Naphthol AS-PH (C.I. 37558 / Azoic Coupling Component 14) produces a yellowish-red shade when coupled with diazo components, whereas other AS series products such as AS, AS-D, AS-OL, and AS-BO produce different shades ranging from red to maroon to blue. AS-PH is specifically chosen for bright yellow-red applications.

Main applications include cotton yarn and cotton fabrics, viscose fiber, silk, nylon, vinylon, and acetate fiber. It is generally not recommended for printing applications.

When used alone or combined with Fast Red KB, Fast Red RL, or Red Salt AL, it produces bright yellowish-red shades. When used with Naphthol AS-D as a primer and combined with Fast Red KB, it is mainly used for dyeing red flag cloth. It is also suitable for dyeing various synthetic fibers.

Naphthol AS-PH offers excellent color yield and good overall fastness properties on cotton and cellulosic fibers. It provides a cost-effective solution for producing bright yellow-red shades compared to reactive dyes, with simpler application processes for deep shades.

Naphthol AS-PH is produced by reacting 2,3-acid (3-hydroxy-2-naphthoic acid) with o-ethoxyaniline in the presence of phosphorus trichloride (PCl3) as a condensing agent in chlorobenzene solvent. The product is then neutralized, distilled, filtered, and dried.