PROCESS FOR PRODUCING POLYLACTIC ACID-BASED RESIN MICROPARTICLES, POLYLACTIC ACID-BASED RESIN MICROPARTICLES THEMSELVES AND COSMETIC USING THEREOF

摘要

Disclosed are a method for producing microparticles of a polylactic acid-basedresin, porous microparticles of a polylactic acid-based resin, saidmicroparticles havinga small particle diameter, showing a high oil absorption ability and beingappropriatelyusable for cosmetics, smooth-surfaced microparticles of a polylactic acid-based resin,said microparticles having a spherical form, showing a narrow particlediameterdistribution and being appropriately usable for toners, and cosmetics usingtheaforementioned microparticles of a polylactic acid-based resin. Theprocess forproducing microparticles of a polylactic acid-based resin comprises:dissolving apolylactic acid-based resin (A) and a polymer (B), which is different frompolylacticacid-based resins, in an ether-based organic solvent (C); applying a shearforce theretoto form an emulsion; and bringing the emulsion into contact with a poorsolvent of thepolylactic acid-based resin (A).According to this production process, it becomespossible to provide porous microparticles of the polylactic acid-based resin,saidmicroparticles having a fusion enthalpy of the polylactic acid-based resin (A)of 5 J/gor greater, having a small particle diameter and showing a high oil absorptionability,and to provide smooth-surfaced microparticles of the polylactic acid-basedresin, saidmicroparticles having a fusion enthalpy of less than 5 J/g, having a sphericalform andshowing a narrow particle diameter distribution.