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CI 21100

Description

CI 21100, also known as Acid Orange 7 or Orange II, is a synthetic azo dye commonly used in cosmetic and personal care products. This water-soluble colorant imparts a vibrant orange hue to various formulations, including soaps, shampoos, and skincare items. Its chemical structure consists of a naphthalene ring coupled with a benzene ring through an azo linkage, resulting in its characteristic color properties.

In cosmetic applications, CI 21100 is valued for its stability and resistance to light, heat, and pH changes, ensuring long-lasting color in products. It is typically used in concentrations ranging from 0.001% to 0.1%, depending on the desired intensity and product type. While generally considered safe for topical use, some individuals may experience sensitivity or allergic reactions.

It's important to note that CI 21100 is not approved for use in products applied near the eyes or on lips in some regions, including the European Union. Regulatory bodies such as the FDA and EU Cosmetics Regulation have established guidelines for its use in cosmetics. Formulators should be aware of potential restrictions and conduct appropriate safety assessments when incorporating this colorant into their products.