Direct Red 23

What are the applications of Application

Direct red 23 is an azo naphtalene dye

Preparation

aniline and N-(4-aminophenyl)acetamide diazo respectively, and N,N’-bis(4-hydroxy-2-sulfonaphthalene-7-yl)urea coupling.

Hazard

Low toxicity by ingestion.

Properties and Applications

red. Purple powder. Soluble in water for colourful red, solubility of 30 g/L (80 ° C), soluble in ethanol for orange, insoluble in acetone. The strong sulfuric acid was great red to product red, diluted light orange for palm. The dye solution to generate strong hydrochloric acid wine red precipitate; Add 10% sulfuric acid into a light blue; Add thick sodium hydroxide solution for red orange; Add 10% sodium carbonate (no change solution. Cellulose fiber of dyeing, dye devoured rate is very good, in the 80 ~ 100 ℃, affinity is the largest. Resistant to acid is very good. Copper ions in dyeing color shade darker; Iron ion in the same light. Mainly used in viscose etc of cellulose fiber dyeing, also can be used for silk, wool, paper and pulp dyeing, also can be used in the manufacture color which have pigment.