HAIR DYEING METHOD AND PRETREATMENT AGENT FOR HAIR DYEING

摘要

PROBLEM TO BE SOLVED: To provide a hair dyeing method causing no skin damage even if a two-pack-type hair dye composition wherein one liquid preparation contains a hydrogen peroxide solution is used.SOLUTION: Prior to hair dyeing using a two-pack-type hair dye composition wherein one liquid preparation contains a hydrogen peroxide solution, pretreatment is carried out by mixing the liquid preparation containing the hydrogen peroxide solution and hydrogen water with a hydrogen concentration of 1 ppm or more to prepare a mixed solution, applying the mixed solution onto the scalp and hair and allowing the mixed solution to leave for a predetermined period.