Washington Esthetician State Board Practice Exam 2026 – Complete Prep Resource

The primary benefit of using surfactants in cosmetic formulations lies in their ability to aid in the emulsification of ingredients. Surfactants work by reducing the surface tension between different phases, such as oil and water, allowing them to blend more effectively. This emulsification is crucial because many cosmetic products contain both oil and water components, and without surfactants, these ingredients would separate. By promoting a stable mixture, surfactants enhance the performance and consistency of products like lotions, creams, and makeup, ensuring that they apply smoothly and evenly to the skin.

While other functions such as thickening products or preserving them are important in formulation, they are not the primary role of surfactants. Thickeners are typically polymers or other substances that increase the viscosity of a formulation, while preservatives are chemical agents that inhibit the growth of microorganisms in products. Surfactants do not inherently make a product oily; their main purpose is facilitating the blending of hydrophilic (water-attracting) and lipophilic (oil-attracting) ingredients.