METHOD FOR PRODUCING CYCLOPOLYMERIZED LACTIC ACID AND CYCLOPOLYMERIZED LACTIC ACID, MEDICINE AND HEALTHY FOOD AND COMSEIC COMPRISING THE SAME CYCLIC POLYMERIZED LACTIC ACID

摘要

PROBLEM TO BE SOLVED: To provide a technique for production by which the content of a cyclic lactic oligomer contained in a cyclopolymerized lactic acid is raised without requiring a complicated apparatus and production process.;SOLUTION: The method for production comprises the following steps. A dehydration condensation step (1) of decompressing and heating up L-lactic acid stepwise in an inert gas atmosphere and thereby obtaining a condensation liquid A having a cyclic type lactic acid oligomer and a chain type lactic acid oligomer formed by dehydration condensation and a lactic acid distillation liquid B comprising mainly the L-lactic acid, a mixing step (2) of mixing the condensation liquid A with the lactic acid distillation liquid B in a prescribed ratio, a cooling step (3) of cooling the resultant mixture C obtained in the mixing step and affording a gel-like substance D, a separation step (4) of adding a solvent dissolving the chain type lactic acid oligomer and L-lactic acid without dissolving the cyclic type lactic acid oligomer to the gel-like substance D, dissolving the substances soluble in the solvent and affording a precipitate E, and a recovering step (5) of recovering the precipitate E and providing a recovered substance G.;COPYRIGHT: (C)2007,JPO&INPIT