| 摘要 |
PURPOSE:To obtain excellent mechanical properties, transparency as well as gas barrier properties by a method wherein polyester resin composition, which contains specific ratio of polyethylene terephthalate resin and specified copolymer polyester resin, is stretched by the specified stretching index. CONSTITUTION:Preform is obtained by mixing 80-95wt.% of polyethylene terephthalate resin and 5-20wt.% of copolymer polyester resin containing dicarboxylic acid constituent unit, which consists of 20-100mol% of isophthalic acid component unit and 0-80mol% of terephthalic acid component unit, dihydroxy compound constituent unit, which consists of 5-90mol% of dihydro- ethoxy-resorcinol component unit and 10-95mol% of ethylene glycol component unit, and 0.05-1.0 pts.mol. of trimethylolpropane constituent unit with respect to 100 pts.mol. of the dicarboxylic acid constituent unit, for forming. A biaxially stretched bottle is obtained from the obtained preform. In addition, the stretching index calculated by the formula in this case is set to be 130 or more. |
