What hair color technique involves using foil to separate different colors?

The technique that involves using foil to separate different colors is known as foiling. This method entails placing strands of hair in a sheet of aluminum foil before applying color, which helps to isolate each section. The foils not only assist with even application but also enhance the processing of the color, allowing for brighter and more defined results.

Foiling is commonly used to create highlights or lowlights, where hair color is lightened or darkened in specific sections to add dimension and depth to the overall look. By using foil, stylists can achieve clean lines and prevent colors from blending together in an undesired way.

Other techniques, like balayage and ombré, do not employ this method. Balayage involves hand-painting color onto the hair for a more natural, graduated effect without the use of foils, while ombré refers to a gradient effect of color transitioning from darker to lighter, typically without the precise separation that foils provide. Similarly, highlights are often achieved using foils, but the term encompasses the broader category of lightening hair, which may not necessarily define the technique itself.