What it is
Hydroxyacetophenone is an organic compound (CAS 99-93-4) with a keto-phenol structure, classed as an acetophenone derivative. In cosmetics it is a handy multifunctional ingredient that works as an antioxidant, helping protect a formula from oxidative degradation, and is also used as a preservative booster and a soothing agent. By supporting a product's preservative system and limiting oxidation, it helps maintain formula stability. In sunscreens it is a formulation aid and not a UV filter.
Safety & warnings
Hydroxyacetophenone is commonly chosen as a gentle, multifunctional aid that lets formulators support a preservative system, and it is often featured in products aimed at sensitive or soothing-focused routines. Public ingredient references do not flag notable irritation or allergen concerns for typical cosmetic use, though anyone with reactive skin should still patch test a new product.
Origin & sourcing
It is a synthetic aromatic compound produced industrially and used both as a cosmetic ingredient and as an intermediate in organic synthesis. Its official cosmetic listings identify its primary function as an antioxidant.
Questions everyone asks
What does hydroxyacetophenone do in a sunscreen?
It acts as an antioxidant and helps support the product's preservative system, and is also used to soothe. It does not provide UV protection.
Is it a preservative?
It is used as a preservative booster and antioxidant rather than a standalone preservative, helping other preservatives work and protecting the formula from oxidation.
Is it suitable for sensitive skin?
It is frequently used in products marketed for sensitive or soothing routines and is not flagged for notable irritation in common references. Patch test if your skin is reactive.