1-[(4-chloro-2-nitrophenyl)azo]-2-naphthol CAS #6410-13-5

1-[(4-chloro-2-nitrophenyl)azo]-2-naphthol (CAS: 6410-13-5) is an azo dye and can also be used as a pigment.
Some of its properties are as follows: Appearance: Usually a dark red solid. Solubility: Slightly soluble in hot toluene and boiling ethanol; yellow-red precipitate after dilution; vermilion in concentrated nitric acid; purple solution in alcoholic potassium hydroxide solution. Others: Has some toxicity.
This compound is similar in structure to para-red (1-(4-nitrophenylazo)-2-naphthol), which has a nitro group added to the para-position of the phenylazo. In terms of application, it can be used to dye cellulose in textiles to a dark brown-red color, but the color is not strong enough and may be easily washed off if it is not dyed correctly. Compared with similar azo pigment varieties, it has poor solvent resistance and poor light fastness.