| 摘要 |
<p>PURPOSE: To improve a stability and a strength by connecting an inner wall surface of a body to a bottom, providing a recess for dividing the inner wall surface into a plurality of segments near the bottom, and previously deforming the recess to the inner wall, thereby upgrading a plastic preform. CONSTITUTION: An inner wall 17 of a body 14 is integrated with a bottom 15, provided with a thick portion 18, and featured by a plurality of segments 19 of the inner wall surface at an end 19a of each segment as starting point. A recess 20 is provided at an end of the segment of the inner wall surface to be a deformable part. The preformed preform is heated by a series of works of heating or blow molding, and heated to a suitable temperature for blow molding. Thereafter, the heated preform is introduced into a casting mold 30 of a predetermined shape, and a movable member 31 is urged to the bottom 15 while blowing a compressed air to incorporate biaxial directivity therein.</p> |
