Formulation base
Cetearyl Alcohol
INCI: Cetearyl Alcohol · also cetostearyl alcohol, cetyl stearyl alcohol, fatty alcohol
A blend of two long-chain fatty alcohols, cetyl and stearyl. Waxy, solid at room temperature, and nothing like the drying alcohols people are told to fear. It is what gives a conditioner its body.
Why it is here
The alcohol that is not that kind of alcohol. It gives the conditioner its body and carries the conditioning agent evenly down the hair instead of dumping it in one place.
Paired with a cationic surfactant, cetearyl alcohol builds a lamellar gel network in the water phase. That network is what makes the product thick, stable and spreadable, and it is also what carries the conditioning agent evenly down the hair shaft instead of dumping it in one place. Rheology studies show this swollen gel phase is the actual structure of a semi-solid cream, not an incidental thickener.
The receipt
The semisolid control cream was structured by a swollen lamellar gel network formed from interaction of cetyl alcohol and the surfactant with continuous phase water; adding cationic polymer collapsed that network into non-swollen cetyl alcohol crystals and produced a mobile, coarser emulsion.
Structure and rheology of semisolid o/w creams containing cetyl alcohol/non-ionic surfactant mixed emulsifier and different polymers. International Journal of Cosmetic Science, 2004. in vitro. PMID 18494913
In practice
- Typical use
- 1 to 6 percent in conditioners and creams, sized against the cationic surfactant it partners with. Alone it thickens; paired, it builds the gel network.
- Pairs with
- Behentrimonium Methosulfate, Panthenol
- Keep apart from
- Nothing. It is one of the most compatible structural ingredients in cosmetic formulation.
- Cautions
- None notable. Fatty alcohols are occasional contact allergens, mostly reported in leg ulcer and dermatitis patients using medicated creams long term. Not drying, and nothing like ethanol or isopropyl alcohol.
Questions people ask
Is cetearyl alcohol drying like other alcohols?
No, and the shared word is the entire source of the confusion. Drying alcohols are small and volatile: ethanol, isopropyl alcohol, denatured alcohol. Cetearyl alcohol is a waxy solid with a 16 to 18 carbon chain that behaves as an emollient and a thickener. Chemically it is closer to a wax than to vodka.
What does it actually do in a conditioner?
It builds the structure. With a cationic surfactant it forms a swollen lamellar gel network in the water phase, and that network is what makes the product thick, stable and evenly spreadable through hair. Remove it and you have a thin liquid that dumps conditioner in one spot instead of distributing it.
Will it build up on my hair?
Not meaningfully in a rinse-out product. It disperses in the wash rather than forming a persistent film the way some silicones can. If your hair feels weighed down, the usual culprits are using too much product, not rinsing thoroughly, or applying conditioner at the roots rather than mid-length down.