Ci
CI 19140 (Yellow 5 / Tartrazine)
CI 19140 · Yellow 5 · Yellow 5 Lake · Yellow 5 Lake (CI 19140)
A synthetic yellow azo dye (tartrazine) used as a color additive — present to color the formula, not to do anything to the skin.
What it does
CI 19140 is the colorant code for tartrazine, a synthetic azo dye approved by the FDA as FD&C Yellow No. 5. In skincare it functions purely as a color additive. The water-soluble dye form colors the liquid phase; the "Lake" variant is the chromophore bound to an aluminum substrate so it can disperse in oil-phase or anhydrous formulas.
Also known as
yellow 5, tartrazine, fd&c yellow no. 5, acid yellow 23
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