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Preservative

Hydroxyacetophenone

Hydroxyacetophenone is a preservative, antioxidant, active used in cosmetic and personal-care formulation. Typical use level is 0.1%–1%. It is both-soluble. Stable in the pH 3–8 range.

At a glance

CAS number
99-93-4
INCI name
Hydroxyacetophenone
Function
preservative, antioxidant, active
Typical use level
0.1%–1%
Solubility
both
Stable pH
3–8

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

4-Hydroxyacetophenone p-Hydroxyacetophenone 1-(4-Hydroxyphenyl)ethanone HAP Phytessence Wakame extract component

Compatibility

Works well with:
Caprylyl Glycol Ethylhexylglycerin Phenoxyethanol 1,2-Hexanediol Glycerin Niacinamide

Hydroxyacetophenone is commonly formulated as part of a multifunctional preservative blend, particularly with caprylyl glycol or ethylhexylglycerin, where synergistic antimicrobial activity allows lower use levels of each component. It is broadly compatible across most cosmetic base types including emulsions, serums, and rinse-offs. No widely documented incompatibilities exist, though performance should be validated in high-pH or heavily chelated systems.

Formulation notes

Hydroxyacetophenone is a naturally occurring phenolic compound (found in plants such as Harpagophytum) used in cosmetics primarily as a multifunctional preservative booster with secondary antioxidant and mild anti-inflammatory properties. Formulators favor it because it is considered a 'clean beauty' compatible alternative to traditional preservatives and it can help reduce the required concentration of other antimicrobial actives. It is generally well tolerated on skin, with a low sensitization potential, and is suitable for rinse-off and leave-on applications.

Frequently asked questions

What is Hydroxyacetophenone?

Hydroxyacetophenone is a preservative, antioxidant, active used in cosmetic and personal-care formulation. Typical use level is 0.1%–1%. It is both-soluble. Stable in the pH 3–8 range.

What is Hydroxyacetophenone used for?

Hydroxyacetophenone is used as preservative, antioxidant, active in cosmetic and personal-care formulations.

What is the typical use level of Hydroxyacetophenone?

Hydroxyacetophenone is typically used at 0.1%–1% in the finished formulation. Always confirm against your supplier's technical data sheet.

What is the CAS number of Hydroxyacetophenone?

The CAS registry number for Hydroxyacetophenone is 99-93-4. Its INCI name is Hydroxyacetophenone.

At what pH is Hydroxyacetophenone stable?

Hydroxyacetophenone is generally stable in the pH 3–8 range.

What ingredients are compatible with Hydroxyacetophenone?

Hydroxyacetophenone works well with Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol, 1,2-Hexanediol, Glycerin, Niacinamide.

Related ingredients

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