In skin care, what does an 'emulsion' usually consist of?

An emulsion is a mixture typically formed by combining two immiscible liquids, such as oil and water. In the context of skin care, emulsions are often classified as either oil-in-water (O/W) or water-in-oil (W/O). In an oil-in-water emulsion, oil droplets are dispersed in water, leading to a lighter texture that quickly absorbs into the skin and is often found in lotions. Conversely, in a water-in-oil emulsion, water droplets are dispersed in oil, creating a thicker, creamier product that provides a more occlusive barrier on the skin, such as found in heavier creams.

This composition is vital for the effectiveness of skin care products, as it influences the texture, absorption, and overall feel of the product when applied to the skin. Understanding this principle helps formulators create products that meet specific skin needs effectively.