Description

What is Hydroxyacetophenone?

Hydroxyacetophenone (INCI: Hydroxyacetophenone; CAS 99-93-4), also called 4-hydroxyacetophenone or p-HAP, is a multifunctional aromatic ingredient supplied as white, needle-like crystals or a crystalline powder with excellent thermal stability. It is best known as an antioxidant and preservative booster: its phenolic structure scavenges free radicals and helps soothe skin, while it enhances the efficacy of conventional preservatives such as phenoxyethanol and ethylhexylglycerin, even in challenging systems. It also stabilizes formulations against oxidation and discoloration, helps neutralize unpleasant odors and contributes a smooth, comfortable skin feel. Highly compatible and effective at low use levels, it is a key component of modern, mild preservation and stabilization concepts in premium skin care.

Key Benefits

• Antioxidant protection: phenolic structure helps scavenge free radicals and protect formulations and skin.
• Preservative booster: enhances the efficacy of primary preservatives, including in demanding conditions.
• Stabilizes formulations: supports thermal and oxidative stability and helps prevent color and odor changes.
• Skin comfort: helps soothe and calm the skin for a comfortable feel.
• Excellent thermal stability: suitable for hot-process and high-temperature formulations.
• Broad compatibility: works well with phenoxyethanol, glycols and most cosmetic bases.
• Low use level: multifunctional benefits delivered efficiently in small amounts.

FAQ

Q1: Is hydroxyacetophenone a preservative on its own? A1: It has weak antimicrobial activity and is primarily used as an antioxidant and preservative booster alongside a primary preservative.

Q2: Why is it paired with phenoxyethanol? A2: The combination is a well-established, mild system that provides reliable broad-spectrum protection with good skin compatibility.

Q3: Does it soothe skin? A3: Yes — its phenolic character is associated with antioxidant and soothing benefits that help keep skin comfortable.