The yellow Tartrazine colorant is a bright yellow cosmetic colorant, identified by the Colour Index CI 19140. Also known as Acid Yellow 23 or E 102, it is used to provide a yellow coloration to cosmetic preparations. Tartrazine is a synthetic colorant authorized in the European Union and is listed in Annex IV of Regulation (EC) No 1223/2009 on cosmetic products. For hair coloring products, its use is limited to a maximum concentration of 0.5% in the ready-to-use product. It must not be used for the coloring of eyelashes or eyebrows. It makes it easy to customize the color of a formulation and can be used alone or combined with other colorants to obtain different shades. It is particularly suitable for bath bombs, shower gels, soaps and other cosmetic preparations.