These are unique polyalkalene glycols which have excellent stabilizing effect on emulsions. Having a high capacity to absorb water and oil, a relatively low percentage is needed in cosmetic formulations. The stabilizing effect is not obtained by thickening, allowing for low viscous stable emulsions to be achieved. As nonionic copolymers, ELFACOS ST 9 and ELFACOS ST 37 polyalkylene glycol derivatives are hydrolytic, pH and electrolyte stable over a very wide temperature range. In decorative cosmetics, they act as binders for powders and provide improved color and payoff in lipsticks and similar products.