Molded object obtained through stretching and thermal fixing and process for producing the same
A draw-molded and heat-set article obtained by draw-molding and heat-setting a hydroxyalkanoate resin comprising chiefly a polylactic acid, the draw-molded and heat-set article having a half-width (X) of a diffraction peak of 2θ=10 to 25° of not larger than 1.220° and, particularly, not larger than 1.100° as found by a broad-angle X-ray measurement. The molded article possesses excellent transparency and heat resistance despite it is made of a spontaneously integrating plastic material. The draw-molded article and, particularly, a container is effectively used for containing beverages.
1. A biaxially draw-blow-molded and heat-set container obtained by biaxially draw-blow-molding and heat-setting a polylactic acid, characterized in that the content of the optically active isomer (d) in the polylactic acid is set to be not larger than 4.0%, and the biaxially draw-blow-molded and heat-set container has a half-width (X) of a diffraction peak of 2 Θ=10 to 25° of not larger than 1.220° as found by a broad-angle X-ray measurement.
2. A biaxially draw-blow-molded and heat-set container as set forth in claim 1 , wherein the half-width (X) is not larger than 1.100°.
3. A biaxially draw-blow-molded and heat-set container as set forth in claim 1 , wherein the half-width (X) and heat shrinkage start temperature (Y, ° C.) as found by thermomechanical analysis (TMA) satisfy the following formula (1),
Y ≧4000 exp(−10 X )+54 (1).
4. A biaxially draw-blow-molded and heat-set container as set forth in claim 1 , wherein the haze of the container is not larger than 10%.
5. A method of producing a biaxially draw-blow-molded and heat-set container as set forth in claim 1 , by draw-blow-molding and heat-setting a polylactic acid characterized in that the content of the optically active isomer (d) in the polylactic acid is set to be not larger than 4.0%, the biaxially draw-blow-molded and heat-set container being heat-set at a temperature of from 70 to 150° C.