| 摘要 |
PURPOSE: To obtain the heat-resistant sheet improved in insufficient heat resistance which is the defect of the lactic acid polymer having excellent biodegradability, capable of being subjected to molding processes such as a vacuum-molding process, an air- pressure molding process and a vacuum and air-pressure molding process, and excellent in the release property from heated molds and in the mold duplicativity, and further to provide the method for producing the molded product suitable for general moldings produced from the sheet, especially food containers, blister-packaging materials, hot- filing containers, etc. CONSTITUTION: The characteristics of the heat-resistant sheet having the lowest storage elastic modulus E' of 80-900kg/cm<2> at a temperature lower by 20 deg.C than the melting point by a test method relating to the temperature dependency of dynamic viscoelasticity comprises preliminarily crystallizing by the annealing of a sheet comprising a lactic acid polymer consisting mainly of polylactic acid and/or monoaxially or diaxially stretch-orienting the sheet. And the method for producing the recrystallized lactic acid molded product comprises molding the heat-resistant sheet in a heated mold within the range from a temperature lower by 20 deg.C than the crystallization temperature Tc of the lactic acid polymer to a temperature below the melting point for 2-600sec. |
