Triarylmethane dye

Triarylmethane dyes are synthetic organic compounds containing triphenylmethane backbones. As dyes, these compounds are intensely colored. They are produced industrially as dyes.

Triarylmethane dyes can be grouped into families according to the nature of the substituents on the aryl groups. In some cases, the anions associated with the cationic dyes (say crystal violet) vary even though the name of the dye does not. Often it is shown as chloride.

Methyl violet dyes have dimethylamino groups at the p-positions of two aryl groups.

Methyl violet 2B

Methyl violet 6B

Methyl violet 10B

Fuchsine dyes have primary or secondary amines (NH₂ or NHMe) functional groups at the p-positions of each aryl group.

Pararosaniline

Fuchsine (hydrochloride salt)

New fuchsine (As chloride)

Fuchsine acid

Phenol dyes have hydroxyl groups at the p positions of at least two aryl groups.

Phenolphthalein

Phenol red

Chlorophenol red

Cresol red

Bromocresol purple

Bromocresol green

Malachite green dyes are related to the methyl violet dyes, except that they contain one phenyl (C₆H₅) group.

Malachite green

Brilliant Green (dye)

Brilliant Blue FCF, a common food colorant.

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