Provided is a composition for in-bath treatment that can treat hair and keep the hair in a voluminous and firm state for a long time. It has an emulsion structure composed of a granular first phase 11 and a second phase 12 in which the first phase 11 is dispersed, and constitutes one of the first phase 11 or the second phase 12, and the average of the primary particles An inorganic particle dispersion 1 comprising a hydrophobic inorganic particle 2 having a particle diameter of 1 nm to 15 μm and an oil-soluble dispersant 5 in which the hydrophobic inorganic particle 2 is dispersed, and the first phase 11 or the second phase 12 The aqueous solvent 10 constituting the other, the surfactant 9 for forming the interface between the first phase 11 and the second phase 12, the first phase 11, the second phase 12, or the first phase 11 and the second phase An invasion treatment component contained in both of the phases 12, the content ratio of the hydrophobic inorganic particles 2 is 0.01 to 20% by mass of the total mass, and the content ratio of the oil-soluble dispersant 5 is the total mass The composition 100 for in bath treatment which is 2-71 mass%.毛髪をトリートメントし、ボリューム感及びハリ・コシのある状態の毛髪を長く保持できるインバストリートメント用組成物を提供する。粒状の第１相１１と、この第１相１１が分散している第２相１２とからなるエマルジョン構造を有し、第１相１１または第２相１２の一方を構成し、一次粒子における平均粒子径１ｎｍ～１５μｍの疎水性無機粒子２と、この疎水性無機粒子２が分散している油溶性分散剤５と、からなる無機粒子分散体１と、第１相１１または第２相１２の他方を構成する水性溶剤１０と、第１相１１と第２相１２との界面を形成するための界面活性剤９と、第１相１１、第２相１２、または第１相１１及び第２相１２の両方に含まれるインバストリートメント成分と、を含有し、疎水性無機粒子２の含有割合が全質量の０．０１～２０質量％であり、油溶性分散剤５の含有割合が全質量の２～７１質量％であるインバストリートメント用組成物１００。
