| 摘要 |
Disclosed is a method for producing a polylactic acid-based film or sheet with improved heat resistance which is a film or sheet formed by subjecting a resin composition containing polylactic acid to a melt film formation method, wherein the resin composition contains (A) polylactic acid, (B) an acidic functional group-modified olefin polymer containing an acidic functional group, having an acid value of from 10 to 70 mg KOH/g, and having a weight average molecular weight of from 10,000 to 80,000, and (C) a tetrafluoroethylene polymer, and the temperature of the resin composition at the time of melt film formation is between a temperature which is higher than the crystallization temperature (Tc) of the resin composition in a temperature falling process by 15°C and a temperature which is lower than the melting temperature (Tm) of the resin composition in a temperature rising process by 5°C, or the resin composition subjected to melt film formation undergoes a step in which the temperature can be controlled at the crystallization temperature (Tc) ± 10°C in a temperature falling process, followed by solidification by cooling. |
