PROBLEM TO BE SOLVED: To provide an acrylic-based resin emulsion suitable for obtaining an excellent hairdressing agent with a good balance between a styling performance (hairdressing performance, re-hairdressing performance, tactile impression) and a cleaned performance.SOLUTION: The invention relates to an acrylic-based resin emulsion for hairdressing agents obtained by emulsion polymerization of a monomer composition [I] and a monomer composition [II]. The monomer composition [I] and the monomer composition [II] satisfy the following conditions (i)-(iii). (i) At least either one of the monomer composition [I] and the monomer composition [II] contains a (meth)acrylate based monomer. (ii) A glass transition temperature (Tg2) of the polymer polymerized using the monomer composition [II] calculated by the formula of Fox is 30°C higher than a glass transition temperature (Tg1) of the polymer polymerized using the monomer composition [I] calculated by the formula of Fox. (iii) The compounding ratio (weight ratio) of the monomer composition [I] and the monomer composition [II] is the monomer composition [I]:the monomer composition [II]=50:50-99:1.COPYRIGHT: (C)2016,JPO&INPIT【課題】スタイリング性能(整髪性能、再整髪性能、触感性)と被洗浄性能にバランスよく優れる整髪剤を得るために好適なアクリル系樹脂エマルジョンを提供する。【解決手段】モノマー組成物[I]及びモノマー組成物[II]を乳化重合して得られることを特徴とする整髪剤用アクリル系樹脂エマルジョンであって、前記モノマー組成物[I]及び前記モノマー組成物[II]が下記の条件(i)~(iii)を満たすことを特徴とする整髪剤用アクリル系樹脂エマルジョン。(i)前記モノマー組成物[I]及び前記モノマー組成物[II]の少なくともいずれか一方が(メタ)アクリレート系モノマーを含む。(ii)前記モノマー組成物[II]を用いて重合したポリマーのFoxの式により求められるガラス転移温度(Tg2)が、前記モノマー組成物[I]を用いて重合したポリマーのFoxの式により求められるガラス転移温度(Tg1)よりも30℃以上高い。(iii)前記モノマー組成物[I]と前記モノマー組成物[II]の配合割合(重量比)がモノマー組成物[I]:モノマー組成物[II]=50:50~99:1である。【選択図】なし
