Permanent deformation method of keratin fibers

The present invention relates to a process for permanent deformation of keratin fibers comprising the steps of : providing the keratin fibers with mechanical fibers a composition comprising one or several sources of ions of formula: wherein X is a group selected from the group consisting of O−, OH, NH2, O—OH, and O—COO−; then placing the keratin fibers in an occlusive space; and then heating the keratin fibers. The present invention also relates to an agent and a kit to be used for the above process.