PROBLEM TO BE SOLVED: To provide a treatment agent for hair deformation which is safety for a human body while giving fewer damages to hair, can add semipermanently or permanently not only a straight shape but also a wave shape and a curl shape to the hair, and can easily change a style created by the agent to another style without using a treatment agent such as a reducer and giving damages to the hair, and a hair treatment method.SOLUTION: A treatment agent for hair deformation contains the following components (A), (B), and (C): (A) glyoxylic acid, a hydrate thereof, or a salt thereof (B) a compound represented by the formula (1) and (C) water, wherein molar ratio (B)/(A) of the content of component (B) to the content of component (A) is 0.01-5 R1 is H or a methyl group X is H, OH or a methoxy group Y is H, O, OH or a methoxy group Z is H, an alkyl group and the like Rx is H, O, a methoxy group and the like Ry is H, OH, an aromatic hydrocarbon group and the like and the break line indicates that it may be a double bond.SELECTED DRAWING: NoneCOPYRIGHT: (C)2016,JPO&INPIT【課題】人体に対し安全で毛髪へのダメージが少なく、半永久的ないし永久的に、直毛形状だけでなくウェーブ、カール形状を付与することもでき、更には一度作ったスタイルを、還元剤などの処理剤を用いずに簡単に、かつ毛髪にダメージを与えることなく、別のスタイルに変えることができる毛髪変形処理剤及び毛髪処理方法の提供。【解決手段】成分(A)~(C)を含有し、成分(A)の含有量に対する成分(B)の含有量のモル比(B)/(A)が0.01以上5以下である毛髪変形処理剤。 (A)グリオキシル酸又はその水和物若しくは塩 (B)式(1)で表される化合物〔R1はH又はメチル基、XはH、OH又はメトキシ基、YはH、O、OH又はメトキシ基、ZはH、アルキル基等、RxはH、O、メトキシ基等、RyはH、OH、芳香族炭化水素基等を示し、破線は2重結合であってもよいことを示す〕 (C)水【選択図】なし
