Define ‘double process’ in hair coloring.

The term ‘double process’ in hair coloring specifically refers to a two-step technique where the hair is first lightened, typically through bleaching, before a color is applied. This method is particularly beneficial for achieving lighter shades on darker hair, as the initial bleaching step creates a blank canvas by removing the existing pigments.

Following the bleaching, a toner or color is applied to achieve the desired hue. This two-step approach allows for more precise color results and can enhance the vibrancy and longevity of the color.

In contrast to this technique, a single-step coloring approach would not involve the preliminary bleaching, making it less effective for significant color changes, especially on darker hair. Additionally, techniques focused solely on temporary colors or those restricted to dark hair do not encompass the full scope of what a double process entails, which specifically combines the lightening and coloring steps for a comprehensive color transformation.