Provided is a convenient, economic and excellent environmentally-adaptive method for producing an O/W emulsified composition with a fine emulsion particle diameter, by using an anionic surfactant forming an α gel in water and a higher aliphatic alcohol.The method of the present invention includes the following steps: a step of formulating an O/W emulsified portion by emulsifying an oil phase containing the following components (A) and (B), and a portion (i.e., the first aqueous phase) of the aqueous phase containing the following components (C), (D) and (E) at a temperature of 80℃ or higher: (A) a higher aliphatic alcohol having a carbon number of from 12 to 26 (B) an oil component (C) an α gel anionic surfactant obtained by forming α gel with the aforesaid component (A) in water (D) a specific alkylene oxide derivative and (E) water and a step of stirring and mixing the aforesaid emulsified portion, and a residual aqueous phase (i.e., the second aqueous phase) at a temperature of from 10 to 35℃, and then cooling wherein the aforesaid (D) alkylene oxide derivative is 1 to 30 mass% of the aforesaid emulsified portion.本發明係使用在水中形成α膠的陰離子性界面活性劑與高級脂肪族醇,以簡便性、經濟性、環境適應性優異的方法提供具有微細的乳化粒徑之O/W乳化組成物。本發明之O/W乳化組成物之製造方法係包括下述步驟:將包含下述(A)與(B)之油相、和包含下述(C)與(D)與(E)之水相的一部分(第1水相),於80℃以上之溫度進行乳化而調製O/W乳化部分的步驟:(A)碳數12至26之高級脂肪族醇、(B)油分、(C)可與前述(A)在水中形成並獲得α膠之陰離子性界面活性劑、(D)特定的伸烷基氧化物衍生物、(E)水;以及藉由將前述乳化部分與10至35℃之殘餘之水相(第2水相)一邊攪拌一邊混合,而進行冷卻之步驟;其中,前述(D)伸烷基氧化物衍生物為前述乳化部分中的1至30質量%。
