| 摘要 |
A two-piece foam plastic cup is made from a rectangular blank and either a bottom disc or expandible plastic foam beads. The rectangular blank is pleated in triangular transverse pleats having their apices adjacent to the rim or mouth of the finished cup to form a frusto-conical sidewall blank with a lapped side seam portion. This sidewall blank is placed in a heated mold with either foam plastic beads or a bottom disc and the mold is heated to fuse the pleats, fuse the lapped side seam, and expand the bottom material and sidewall material into a fused unitary cup or container structure having a sidewall of uniform thickness but with visible pleats therein, despite its resulting smooth surface. |
