Method for producing a polylactic acid-based resin particles, polylactic acid smooth surface narrow particle size distribution with a suitable sphericity polylactic acid-based resin particles of porous shape high oil absorption in a suitable small particle size, the toner use in cosmetic applications system resin particles, and I will provide the cosmetics using a polylactic acid resin particles of these. Was dissolved in (C) an ether-based organic solvent and the polymer (B) different from the polylactic acid-based resins polylactic acid resin (A), and to form an emulsion by applying a shear force, the polylactic acid resin (A) method for producing a polylactic acid resin particles contacting the poor solvent. This manufacturing method, melting enthalpy polylactic acid-based resin (A) is in the 5J / g or more, and polylactic acid-based resin particles porous high oil absorption, melting enthalpy at 5J / g less than true in small particle size a sphere, it is possible to provide a polylactic acid resin particles a smooth surface the particle size distribution is narrow.ポリ乳酸系樹脂微粒子の製造方法、化粧品用途に好適な小粒子径で吸油量の高い多孔質形状のポリ乳酸系樹脂微粒子、トナー用途に好適な真球で粒子径分布の狭い表面平滑なポリ乳酸系樹脂微粒子、およびこれらのポリ乳酸系樹脂微粒子を用いた化粧品を提供する。ポリ乳酸系樹脂(A)およびポリ乳酸系樹脂とは異なるポリマー(B)をエーテル系有機溶媒(C)に溶解し、剪断力を加えてエマルションを形成した後、ポリ乳酸系樹脂(A)の貧溶媒を接触させるポリ乳酸系樹脂微粒子の製造方法。この製造方法により、ポリ乳酸系樹脂(A)の融解エンタルピーが5J/g以上で、小粒子径で吸油量の高い多孔質なポリ乳酸系樹脂微粒子や、融解エンタルピーが5J/g未満で、真球で、粒子径分布が狭い平滑表面なポリ乳酸系樹脂微粒子を提供可能となる。
