PROBLEM TO BE SOLVED: To provide the manufacturing method of a stable oil-in-water emulsion composition in which microparticles are uniformly dispersed and which has mono-dispersed particle size distribution.SOLUTION: In the manufacturing method of the oil-in-water emulsion composition, a mixture containing (A) a surfactant, (B) an oily component in a liquid state at 25°C and (C) water is formed into high pressure fluid, and a high-pressure jet stream is made to collide with a hard body supported in a chamber for collision to be emulsified. The manufacturing method of the oil-in-water emulsion composition includes a jet nozzle jetting raw liquid, an introducing passage feeding the high speed fluid of the raw liquid to the jet nozzle, a cylindrical high speed flow passage receiving the high speed jet stream jetted from the jet nozzle and passing it, and jetting it from an outlet opening to make it collide with the surface of the hard body, and an outflow passage for discharging the fluid after collision to the outside of the apparatus.COPYRIGHT: (C)2010,JPO&INPIT【課題】微小粒子が均一に分散し、単分散な粒子径分布で、安定な水中油型乳化組成物を製造する方法の提供。【解決手段】(A)界面活性剤、(B)25℃で液状の油性成分及び(C)水を含有する混合物を高圧流体となし、衝突用チャンバー内に支承された硬質体に高圧噴流を衝突させ乳化させる水中油型乳化組成物の製造方法であって、原料液を噴射する噴射ノズル、噴射ノズルへ原料液の高速流体を供給する導入流路、噴射ノズルから噴射された高速噴流を受け入れて通過させた後に出口開口から噴出して前記硬質体の表面へ衝突させる円筒状の高速流路と、衝突後の流体を装置外へ排出するための流出流路から構成される水中油型乳化組成物の製造方法。【選択図】なし
