Direct red 194 (C.I. 35785)

Подготовка

2-Amino-3,5-dichlorobenzenesulfonic acid diazo, and m-Toluidine?coupling, and then a sulfonic acid hydrolysis off base, its product (2 Moore) diazo, coupled with N,N’-bis(4-hydroxy-2-sulfonaphthalene-7-yl)urea.

Свойства и приложения

yellow light red. Soluble in water for blue-ray red, slightly soluble in alcohol. The strong sulfuric acid for blue, purple red after diluted. The dye solution to join strong hydrochloric acid for dark purple, have precipitation; Add thick sodium hydroxide solution for purplish red color, have precipitation.