Cetostearyl alcohol
Skim through
What it does: emollient, viscosity controlling, emulsifying, surfactant/cleansing, emulsion stabilizing, foam boosting, opacifying
Also called: cetearyl alcohol
The science
Cetostearyl alcohol helps to stabilize oil-water mixes (emulsions). It’s a fatty alcohol and a mix of cetyl and stearyl alcohol (other emollient fatty alcohols). Fatty alcohols have a long oil-soluble (and thus emollient) tail part that makes them absolutely non-drying and non-irritating, hence they are totally ok for the skin.
Benefits for your hair
Prevents dryness
As an emollient, cetostearyl alcohol is considered an effective ingredient for soothing and healing dry skin. It's great at hydrating and moisturizing, too which helps to soften the hair.
Prevents tangles
As it's hydrating, it provides slip to help detangle hair better.
TLDR
Cetostearyl alcohol helps to soften and detangle hair, thicken and stabilize products, and prevent dryness.