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Informations sur le CI 42090 utilisé en cosmétique.

What is "CI 42090" and what is its purpose?

In some ingredient lists of cosmetic products, we can spot the term "CI 42090". But what is it? Here are the key details to remember about this ingredient.

Published February 5, 2024, by Stéphanie, Doctorate in Life and Health Sciences — 3 min read

What is CI 42090?

CI 42090 is a dark blue synthetic dyesubject to regulation. Indeed, to be approved, this dye must meet purity criteria defined in Directive 95/45/EC of the Commission. Classified among triarylmethane dyes, it is also known by other names, such as Blue 1 Lake in the United States or E133 as a food dye. It is particularly found in shampoos, hair dyes, foundations, mascaras, lipsticks, eyeliners, face powders, and more...

Chemical formula: C37H34N2Na2O9S3.

Molecular Weight: 792.84 g/mol.

Solubility: Soluble in water.

Organoleptic properties: Fine or granular blue powder.

How is it designed?

The cosmetic dye CI 42090, of synthetic origin, is composed of salt disodium of the α-[(N-ethyl-sulfo-3-benzylamino)-4-phenyl]-α-(N-ethyl-sulfo-3-benzylamino-4)-cyclohexadiene-2,5-ylidene) toluenesulfonic-2 acid and its isomer, as well as accessory coloring materials. It is obtained by precipitating 2-formylbenzenesulfonic acid with metallic salts such as aluminum, barium, or others.

What is its utility in cosmetics?

The CI 42090 is used in skin and hair care as a dye. It serves to give them a bright blue color. It can also be mixed with other dyes to produce a wide range of shades and hues.

The CI 42090 has been used in the formulation of certain shades of our tinted lip balms, as well as our tinted lip oils.

Is CI 42090 dangerous?

The CI 42090 has been deemed safe for use on skin and hair. It presents no risk. However, it can cause irritation and redness in people allergic to dyes. That's why a patch test of products containing these dyes is recommended.


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