Acid Yellow 128

Chemical Properties

Yellowish brown powder. Aqueous solution is light yellow colloidal. Yellow in concentrated sulfuric acid, light yellow solution after dilution. Does not change color in concentrated hydrochloric acid, diluted light yellow solution. Destroyed in concentrated nitric acid, the residue is yellow; in dilute nitric acid it is light tender yellow. Yellow in concentrated sodium hydroxide solution, pale yellow when diluted.

Uses

Acid Yellow 128 is mainly used for dyeing wool, silk, and nylon in neutral or weakly acidic dye baths, as well as for dyeing vinylon in neutral dye baths. It is also used for direct printing on wool, silk, and nylon fabrics. When used for dyeing wool with other fibers in the same bath, nylon will develop a deep red color, silk a slightly lighter color, and cotton, viscose fiber, and diacetate fiber will not be stained. It can also be used for leather dyeing.

Preparation

3-Amino-4-hydroxybenzenesulfonamide diazo, and 3-Oxo-N-phenylbutanamide coupling, and then use cobalt chloride complex.

Properties and Applications

green light yellow. Tan evenly all powder, soluble in water. The strong sulfuric acid for yellow, diluted light yellow solution; In nitric acid was damaged in, a small residual yellow; In strong hydrochloric acid in the same light, diluted light yellow; In the thick of sodium hydroxide solution for yellow, diluted light yellow. Its water solution for light yellow. Structure and the C.I.Acid Yellow 151 the same. Used for wool, silk, polyamide, d theory and

Standard	Light Fastness	Soaping		Persperation Fastness	Oxygen bleaching		Fastness to seawater
		Fading	Stain		Fading	Stain	Fading	Stain
ISO	7	4-5	4-5	4-5	4-5	4	5	5