preservative
Caprylyl Glycol
Multifunctional preservative booster and conditioning humectant in K-beauty haircare and prestige skincare. Frequently paired with 1,2-hexanediol or phenoxyethanol for broad-spectrum preservation.
Benefits
- Broad-spectrum antimicrobial
- Conditioning humectant function
- Preservative synergy reducing co-preservative concentrations
- Skin-feel modifier
- Accepted in natural and clean formulation frameworks
Example uses
- Purple shampoos
- Conditioning hair treatments
- Lightweight serums
- Gel moisturisers
- Mist formulations
Mechanism of action
8-carbon aliphatic diol disrupts microbial cell membranes by integrating into the lipid bilayer, increasing permeability and causing cytoplasmic leakage. Longer carbon chain (C8 vs C6 for 1,2-hexanediol) provides enhanced activity against fungi at lower concentrations. Hydroxyl groups provide secondary humectant function.
Clinical evidence · Moderate
Safety assessed by CIR and SCCS. Antimicrobial efficacy documented in MIC studies.
Effective concentration range
0.1–1% (preservative booster); up to 2% in conditioning applications
Formulation notes
Effective pH 3–8. Provides conditioning benefit in haircare. Often formulated at 0.1–0.5% as a booster.
Watchouts
At >1% some reports of irritation in sensitive individuals. Good safety profile at cosmetic use levels.
Stacks with
Controversies & overclaims
No significant controversy. Subject to same naturally-derived branding scrutiny as other synthetic diol preservatives.
Market positioning
Marketed as gentle multifunctional preservative. Accurate — genuine formulation advantage.
Comedogenicity
0 / 5
Sensitisation risk
Low
INCI & aliases
Caprylyl Glycol
1,2-octanediol · octane-1,2-diol
Clean beauty perception
Generally accepted in clean beauty as paraben-alternative preservative. Synthetic diol — similar naturally-derived branding questions as 1,2-hexanediol apply.
More preservative
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