Parison for stretch molding

摘要

A parison for stretch molding comprising a side wall which forms a barrel portion of a hollow vessel during blow molding, a bottom wall which continues from the side wall and forms the bottom wall of the vessel during the blow molding, and a padding portion which is gradually made thin outward in the radial direction substantially from the central portion of the bottom wall and which is provided in the internal periphery of the bottom wall. The parison can therefore prevent the thickness of the bottom of the vessel from being too small after blow molding of th parison, but achieve sufficient strength without using any excessive material and achieve and improvement in productivity of the parison by increasing the cooling efficiency thereof.