| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable a plastic container to be easily centered and shaped to have a bottom shape with a uniform wall thickness by forming in an arc face broadening downward with an inclined part continuous from the peripheral edge of a top part and facing outward, and forming a second inclined part broadening downward continuous to the outer peripheral edge of the inclined part. SOLUTION: A first inclined part 3 is continuous downward from the peripheral edge of a top part 2 formed in a slightly recessed shape, and further, is formed into a parabolic or an arc sector shape spread outward. A second inclined part 4 is tapered to be broadened downward in a fan shape in such a way that it is continuous to the outer peripheral edge of the first inclined part 3. Therefore, in a first molding step, a bottom die 12 with a middle-part- protruding tapered plane is used, so that the center of the bottom part 72 of an intermediate container 7 is molded into a concave profile. In addition, in a second molding step, a bottom die 1 with the first inclined plane part 3 of a parabolic sector shape facing outward from the peripheral edge of a slightly recessed top part 2, is used.</p> |
