STEARETH-2
Steareth-2 is a long-chain ingredient used to bring together components that would otherwise separate in a cosmetic, such as water and oils. Its structure combines an octadecyl portion, similar to a fatty tail, with two ethylene oxide units; that arrangement accounts for its affinity for different phases of a formula.
STEARETH-2: what it is
Steareth-2 is a long-chain ingredient used to bring together components that would otherwise separate in a cosmetic, such as water and oils. Its structure combines an octadecyl portion, similar to a fatty tail, with two ethylene oxide units; that arrangement accounts for its affinity for different phases of a formula.
The number 2 is meaningful: it distinguishes Steareth-2 from other Steareth ingredients by the number of ethoxylated units attached to the same chain. That difference changes the balance between the portions that interact with oil and water, helping formulators select an emulsifying system rather than treating similarly named ingredients as interchangeable.
STEARETH-2: what it does in cosmetics
In creams, lotions, and other products that contain water and an oily phase, Steareth-2 works as an emulsifying surfactant. In practical terms, it helps disperse oil droplets through the water phase and keep the mixture more uniform, so texture and application are less likely to feel separated or uneven. It can also take part in cleansing systems, where surfactants help oily residues mix with water during rinsing.
In a stability experiment with buriti oil, Steareth-2 was evaluated in systems combined with Ceteareth-5 or Ceteareth-20. That result concerns the stability of those complete emulsions and supports its technical use in similar systems, but it does not show that the ingredient alone treats skin, wrinkles, dark spots, or any condition.
STEARETH-2: conditions and care
The Cosmetic Ingredient Review considers alkyl PEG ethers safe under the assessed conditions of use when the formulation is nonirritating. This conclusion concerns the finished formulation and does not replace irritation testing for a specific product.
Products containing this ingredient
See which products include it and the name used in each composition.
