HomeIngredient LibraryPropanediol

Humectant

Propanediol

Propanediol is a humectant, solvent, emollient, preservative booster used in cosmetic and personal-care formulation. Typical use level is 1%–20%. It is water-soluble. Stable in the pH 3–10 range.

At a glance

CAS number
504-63-2
INCI name
Propanediol
Function
humectant, solvent, emollient, preservative booster
Typical use level
1%–20%
Solubility
water
Stable pH
3–10

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

1,3-Propanediol Trimethylene Glycol PDO Zemea DuPont Propanediol

Compatibility

Works well with:
Niacinamide Hyaluronic Acid Glycerin Phenoxyethanol Sodium Hyaluronate Panthenol

Propanediol is broadly compatible with most cosmetic ingredients including actives, preservatives, and film formers. It is frequently used as a co-solvent to aid dissolution of poorly water-soluble actives and fragrance components. It can enhance the efficacy of certain preservatives such as phenoxyethanol, potentially allowing lower use levels of those ingredients.

Formulation notes

Propanediol is a bio-based diol (often derived from corn sugar fermentation) used as a humectant, solvent, and skin-conditioning agent. It offers a lighter, less sticky feel compared to glycerin, making it popular in serums, toners, and lightweight moisturizers. It is generally well tolerated, non-irritating, and considered safe at typical cosmetic use levels; it is also readily biodegradable.

Frequently asked questions

What is Propanediol?

Propanediol is a humectant, solvent, emollient, preservative booster used in cosmetic and personal-care formulation. Typical use level is 1%–20%. It is water-soluble. Stable in the pH 3–10 range.

What is Propanediol used for?

Propanediol is used as humectant, solvent, emollient, preservative booster in cosmetic and personal-care formulations.

What is the typical use level of Propanediol?

Propanediol is typically used at 1%–20% in the finished formulation. Always confirm against your supplier's technical data sheet.

What is the CAS number of Propanediol?

The CAS registry number for Propanediol is 504-63-2. Its INCI name is Propanediol.

At what pH is Propanediol stable?

Propanediol is generally stable in the pH 3–10 range.

What ingredients are compatible with Propanediol?

Propanediol works well with Niacinamide, Hyaluronic Acid, Glycerin, Phenoxyethanol, Sodium Hyaluronate, Panthenol.

Related ingredients

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