| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method for a two-layer foamed blow- molded article which can form a foamed layer in an outer layer portion and a solid layer in an inner layer portion and can keep the inner surface of the inner layer portion smooth, while using a general-purpose molding machine for one layer. SOLUTION: A pair of splits 5a and 5b of a blow mold being put in an opened state, a foamed parison 2 obtained by chemical or mechanical foaming is introduced from a die head 1 and then the mold is closed. Next, low-pressure air is blown into a parison 3 held in the blow mold 5, so as to make the parison 3 lie along a mold surface 51, and the outer layer 31 of the parison is cooled from the mold surface 51 through the outer surface of the parison 3 in contact with the mold surface 51. Thereby the outer layer 31 of the parison is molded and hardened as it remains foamed with foams 33 existing. By blowing high- pressure air into the parison 3 successively, the foams 33 existing in the inner layer 32 of the parison being still in a softened state are eliminated and the inner layer 32 is molded to be the solid layer 42. |
