PROBLEM TO BE SOLVED: To provide silicone-including silica nanoparticles that can attain excellent transparency and storage stability of a dispersion when the particles are dispersed in a dispersion medium, and a method for producing the same.SOLUTION: The silicone-including silica nanoparticles includes a siliceous shell region and silicone present in a hollow part enclosed by the shell region. The silicone-including silica nanoparticles have an average primary particle size of 10-100 nm and the shell region has an average shell thickness of 2-20 nm as measured using an electron microscope. The method for producing the silicone-including silica nanoparticles involves a step (I) of pressurizing by a high pressure emulsification method a solution to be emulsified containing silicone (component A), a surfactant (component B), and an aqueous solvent (component C) containing water, so as to form an emulsion containing silicone-containing emulsified droplets, and a step (II) of mixing the emulsion with alkoxysilane (component D) so as to precipitate the silicone-including silica nanoparticles that contain the shell region and silicone present within the hollow part enclosed by the shell region.COPYRIGHT: (C)2013,JPO&INPIT【課題】分散媒に分散された状態で、分散液の優れた透明性と保存安定性とを実現可能とする、シリコーン内包シリカナノ粒子、及びその製造方法を提供する。【解決手段】本発明のシリコーン内包シリカナノ粒子は、シリカを含む外殻部と、外殻部に囲まれた中空部内に存在するシリコーンとを含む。電子顕微鏡を用いて測定した、シリコーン内包シリカナノ粒子の、平均一次粒径は10~100nm、外殻部の平均外殻厚は2~20nmである。シリコーン内包シリカナノ粒子の製造方法は、シリコーン(成分A)と界面活性剤(成分B)と水を含む水系溶媒(成分C)とを含む乳化対象液を高圧乳化法により加圧して、シリコーン含有乳化滴を含んだ乳濁液を形成する工程(I)と、乳濁液とアルコキシシラン(成分D)とを混合して、外殻部と外殻部に囲まれた中空部内に存在するシリコーンとを含む、シリコーン内包シリカナノ粒子を析出させる工程(II)とを含む。【選択図】図1
