What does a 'Double Process' color treatment involve?

A 'Double Process' color treatment primarily involves two distinct steps: first, the hair is bleached to lift the original color, and then a color is applied afterward. This method is particularly used for achieving lighter hair shades or vibrant colors that require significant lifting of the natural hair pigment.

The initial bleaching step is crucial because it removes the existing color, allowing for the new shade to be applied more effectively. It provides a blank canvas that is necessary for achieving the desired final result, especially when moving from darker to lighter colors or applying vivid tones.

The other choices do not encapsulate the essence of a 'Double Process':

• Applying color without bleaching typically refers to single-process techniques where the existing hair color is either enhanced or changed without any lightening involved.
• Using multiple colors at once can occur in various coloring techniques, but it does not necessarily imply that both bleaching and an additional color application take place in a sequential manner.
• Processing hair in two separate appointments suggests a different approach and timeframe than a 'Double Process', which is done within the same session.

In summary, the correct choice accurately describes a method commonly used in professional hair coloring that requires both the removal of the current color and the subsequent application of a new one to achieve the desired