Which hair treatment is known to be self-heating?

The self-heating nature of a treatment often refers to its ability to generate heat as a part of the chemical process that occurs during the treatment. In the context of hair treatments, an alkaline perm is known for this characteristic. It is typically formulated with alkaline agents that allow for the hair cuticle to lift and allows for greater penetration of the perm solution. The reaction produces heat which can enhance the effectiveness of the perm by making the hair more pliable, thus enabling the chemical curls to set more effectively.

This self-heating effect is beneficial as it accelerates the development of the curls and ensures that the hair can hold the desired shape post-treatment. By contrast, other treatments such as acid perms often require external heat, while deep conditioning treatments and hot oil treatments are primarily focused on hydration and nourishment, rather than chemical alteration of the hair structure through self-generated heat.