Oil and water do not mix, as you might remember from physics class. Oil molecules are hydrophobic, meaning they repel water, which is why they’ll form a distinct layer on top of water.

But with a bit of tinkering, chemists can combine oil and water into biphasic formulations, providing those two steps into one product.

Take the Strip Caviar Jelly Makeup Remover, for example: It contains a biphasic, microfluidic technology to suspend the tiny bubbles in the jar, which burst once massaged into the skin. (Yes, it’s just as satisfying as it sounds.) Once emulsified with water, it transforms into a thin, watery confection that easily removes all lingering makeup and sunscreen residue. 

Renée Rouleau’s Better Than Balm also contains a dual-phase technology powered by sucrose laurate—a sugar-based emulsifier that helps provide an oil-to-gel transformation. The cleanser starts as a silky, lightweight oil, then evolves into a milky gel to whisk away grime and stubborn makeup. 

Covey’s First Of All Cleanser, on the other hand, delivers more of a foaming experience, with babassu oil and coconut surfactants. “Babassu oil nourishes and cleanses the skin but is the catalyst of the cleanse serving as the oil-based part as the makeup remover part,” notes board-certified dermatologist Julie Russak, M.D. “The coconut surfactants are what binds to the dirt and makeup serving as the foam to lift away the dirt, the grime, [and] the makeup without stripping the skin and hydrating.” 

It’s really about how different actives cooperate at specific concentrations that allow them to deliver both oil- and water-based cleansing benefits, adds Russak.