Nitrophenol (inci)

Nitrophenol(s), mono-nitrophenol(s), are substances that are used in cosmetic products, among other things. The structure consists of a benzene ring with added hydroxy (-OH) and nitro group (-NO2) as substituents. Their different arrangement results in three constitutional isomers (2-nitrophenol, 3-nitrophenol, 4-nitrophenol) with the molecular formula C6H5NO3. Nitrophenols are used as hair dyes.

The nitrophenols are crystalline solids. They are hardly soluble in water, soluble in ethanol and ether. The substances are widely used in the chemical and pharmaceutical industry.
In cosmetics the following nitrophenol compounds are used as hair dyes:

4-amino-3-nitrophenol (INCI).

2-amino-6-chloro-4-nitrophenol (INCI).

2-amino-3-nitrophenol (INCI).

2-Chloro-6-ethylamino-4-nitrophenol (INCI).

4-hydroxypropylamino-3-nitrophenol (INCI).

4-nitroguaiacol (INCI).

3-Nitro-p-hydroxyethylaminophenol (INCI).