A red monoazo dye, listed as a hair-dyeing ingredient and regulated in Annexes III and IV.
What it is
Acid Red 33 is a synthetic red monoazo dye, the disodium salt of 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonic acid, with the Colour Index number CI 17200. CosIng lists it as a hair-dyeing ingredient. In the EU it is covered by an entry in Annex III (substances subject to restrictions) for non-oxidative hair dye products, and as a colorant it is also listed in Annex IV (colorants).
Where it is used
Appears on the ingredient lists of a small number of products.
Limits of interpretation
The INCI list shows which ingredients are present, not how much of each. Above 1%, ingredients are listed in descending order of weight; below 1% the order is free.
See the EU regulation section for the applicable limits, conditions and label warnings. Its position on the list does not show the final shade, which depends on the combination of dyes in the product.
Functions
- Hair dyeing
- Imparting color to hair. Hair dyeing preparations may be temporary, semi-permanent, permanent, depending on the length of time the colorant remains on the hair.
EU regulation
- As of
- 3 November 2026 · (EC) 2009/1223
- Product type
- Hair dye substance in non-oxidative hair dye products
- Maximum concentration
- 0.5 %
- As of
- 3 November 2026 · (EC) 2013/344
Safety Gate alerts (EU)
1 alerts about dangerous cosmetics in the EU mention this substance. An alert concerns a specific product, usually one that breaks EU rules.
- IVISMILE – Colour Corrector V34 (2024-03-21)