HomeIngredient LibraryZinc Oxide

Uv Filter

Zinc Oxide

Zinc Oxide is a uv_filter, active, colorant, preservative used in cosmetic and personal-care formulation. Typical use level is 1%–25%. It is null-soluble. Stable in the pH 5–9 range.

At a glance

CAS number
1314-13-2
INCI name
Zinc Oxide
Function
uv_filter, active, colorant, preservative
Typical use level
1%–25%
Solubility
null
Stable pH
5–9

CAS number and synonyms are sourced from PubChem. Function, usage levels, pH and compatibility are AI-assisted formulation guidance — verify against your supplier's technical data sheet and applicable regulations before use.

Also known as

Zinc oxide (ZnO) Zincum Oxydatum Zinc paste Zinci Oxydum Zinc (as oxide) Zinc oxide emulsion Zinc (as zinc oxide) Lassar's Paste Oxide, Zinc Paste, Lassar's aloevella calahist

Compatibility

Works well with:
Titanium Dioxide Dimethicone Cyclopentasiloxane Caprylic/Capric Triglyceride Jojoba Oil Beeswax Niacinamide Tocopherol Iron Oxides Silica

Use caution with:
L-Ascorbic Acid Ascorbic Acid Kojic Acid EDTA Fatty Acids (free)

Zinc Oxide can oxidize or degrade vitamin C (L-Ascorbic Acid), reducing its efficacy and causing discoloration. It may react with free fatty acids to form zinc soaps, destabilizing emulsions. Chelating agents like EDTA can complex with zinc ions, potentially reducing UV protection performance.

Formulation notes

In the EU, max authorized concentration is 25% as a UV filter (Annex VI, Regulation EC 1223/2009); nano-grade ZnO requires specific labeling. In the US (FDA), recognized as a Category I OTC sunscreen active up to 25%. Insoluble in water and oil — dispersed as a particle; surface-treated grades (e.g., dimethicone-coated) improve dispersibility and reduce whitening. Avoid inhalation of powder during manufacturing.

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