Mordant Red 21

4-Amino-N-ethyl-N-(naphthalen-1-yl)benzarnide diazo, and 4-Benzamido-5-hydroxynaphthalene-1,7-disulfonic acid9?coupling.

colourful red to blue light red. Soluble in water for red, moderate soluble in alcohol for product red. The strong sulfuric acid for product red, diluted into a peach. In water solution to join strong hydrochloric acid for product red; Add thick sodium hydroxide solution for orange brown

Standard	Light Fastness	Soaping		Persperation Fastness	Oxygen bleaching		Fastness to seawater
		Fading	Stain		Fading	Stain	Fading	Stain
ISO	4-5	4	5	4	2	4	4-5	4-5
AATCC	4-5	4	4	4	2	2-3	4	4