Ingredients
Colorant

Toluene-2,5-Diamine

Caution Official INCI name

A hair-dye ingredient used in place of PPD in many permanent dyes. It's a strong allergen too — many people allergic to PPD react to it. Patch test before every colouring.

What it does

Colorant. Pigments and dyes (often listed as CI numbers).

Worth knowing

Sensitizer

Can cause contact allergy that, once developed, returns on every exposure.

Also written as

Scans recognise it under every one of these names.

2,5-DiaminotoluenePTD

“Toluene-2,5-Diamine” is its name in the EU glossary of common ingredient names (no. 28957), the names labels in the EU must use. © European Union, EUR-Lex.