| 摘要 |
<p>PROBLEM TO BE SOLVED: To make transparency, heat resistance and gas barrier properties excellent by solving a problem which polyethylene naphthalate possesses wherein whitening occurs when a polyethylene naphthalate resin is molded into a hollow container. SOLUTION: A hollow container consisting of a resin compsn. contg. a polyethylene nephthalate resin and comprising a trunk part and a bottom part is a container wherein at an arbitrary measuring point on the outer periphery of the trunk part of the container, when birefringence in one direction (direction X) on the outer peripheral face of the measuring point isΔnx and birefringence in the direction (direction Y) at right angles to the above described direction on the outer peripheral face isΔny,Δnx andΔny are at least 0.05 andΔnx/Δny is 0.7-1.3. The hollow container like this has a haze of the trunk part of at most 8%. The hollow container is prepd. by performing injection molding of a resin compsn. contg. polyethylene naphthalate to obtain a preliminary molding and then, performing simultaneous stretch blow molding in length and peripheral directions while the preliminary molding is heated at 120-150 deg.C.</p> |
