A synthetic blue colorant.
What it is
CI 42090 is the Colour Index number of a synthetic blue dye, also used in foods (E133). It gives products a blue or, combined with yellow, green colour.
Where it is used
Found in shampoos, shower gels, mouthwashes, toothpastes and soaps.
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.
Colorants are allowed only if listed in Annex IV of the EU Cosmetics Regulation; they are named by CI number and may appear in any order.
Functions
- Colorant
- Exclusively or mainly intended to colour the cosmetic product, the body as a whole or certain parts thereof, by absorption or reflection of visible light; (precursors of oxidative hair colorants shall be deemed colorants). All authorised colorants are substances in the positive list of Annex IV to the Cosmetics Regulation 1223/2009.
- 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
EU · Annex IV, entry 63Benzenemethanaminium, N-ethyl-N-(4-((4-(ethyl((3-sulfophenyl)methyl)amino)phenyl)(2-sulfophenyl)methylene)-2,5-cyclohexadien-1-ylidene)-3-sulfo-, hydroxide, inner salt, disodium salt
- Conditions and warnings
- Purity criteria as sset out in Commission Directive 95/45/EC (E 133)
- As of
- 3 November 2026 · (EC) 2009/1223
EU · Annex III, entry 190Benzenemethanaminium, N-ethyl-N-[4-[[4-[ethyl-[(3-sulfophenyl)-methyl]-amino]-phenyl](2-sulfophenyl)methylene]-2,5-cyclohexadien-1-ylidene]-3-sulfo, inner salts, disodium salt and its ammonium and aluminium salts (15); Acid Blue Acid Blue 9 Ammonium salt; CI 42090.
(see note 17)
- Product type
- Hair dye substance in non-oxidative hair dye products
- Maximum concentration
- 0.5%
- As of
- 3 November 2026 · (EC) 2013/344
Products with this ingredient (1275)
- Sensodyne Extra Whitening · Haleon
- Face Peeling Exfoliating 3 in 1 · Cien
- Tea Tree Skin Clearing Facial Wash · The Body Shop
- Olive Shower Gel · The Body Shop
- Spa of the World™ Tahitian Tiaré Body Wash · The Body Shop
- Dewberry Body Yogurt · The Body Shop
- Dewberry Shower Gel · The Body Shop
- Swipe It Moisturising Lip Balm · The Body Shop
- Maca Root & Aloe Post-Shave Water-Gel For Men · The Body Shop
- Whipped Matcha & White Chocolate Body Lotion-to-Milk · The Body Shop
- Whipped Matcha & White Chocolate Body Butter · The Body Shop
- Guarana and Coffee Energising Moisturiser For Men · The Body Shop

