PROBLEM TO BE SOLVED: To provide hair transformation pretreatment agents having high adaptability to various alkalinity and pH of a first agent for hair transformation and additionally having high viscosity, and to provide hair transformation treating method using the pretreatment agent.SOLUTION: The hair transformation pretreatment agent contains a cationic surfactant, a higher alcohol, acid, polyoxyethylene hardened castor oil whose average addition mole number of ethylene oxide is 50 or more, and a salt of acid and alkali, the compound amount of the salt of acid and alkali is 1.0 mass% or more, and it is acidity. The hair transformation treating method comprises a pre-treatment step of applying the hair transformation pretreatment agent to the hair, and a reduction step of applying an alkaline first agent for hair transformation, in which a reducing agent is compounded, to the hair.SELECTED DRAWING: None【課題】毛髪変形用第1剤の様々なアルカリ度及びpHに高い適応性がある上に、高い粘性の毛髪変形用前処理剤、及び、当該前処理剤を使用する毛髪変形処理方法の提供。【解決手段】毛髪変形用前処理剤は、カチオン界面活性剤、高級アルコール、酸、酸化エチレンの平均付加モル数が50以上であるポリオキシエチレン硬化ヒマシ油、及び、酸とアルカリとの塩が配合され、酸とアルカリとの塩の配合量が1.0質量%以上であり、酸性である。毛髪変形処理方法は、その毛髪変形用前処理剤を毛髪に塗布する前処理工程と、還元剤が配合されたアルカリ性の毛髪変形用第1剤を毛髪に塗布する還元工程と、を備える。【選択図】なし
