| 摘要 |
PURPOSE:To obtain a molded item with a rugged pattern at the lamination interface by a method wherein a rugged pattern is formed in such a manner that a tongued-and- grooved face gradually vanishes from the end face of a mouthpiece land to the inner part on at least one side face of the intersection of mouthpiece lands, which respectively communicate to a main extruder and to an auxiliary extruder. CONSTITUTION:An end face having a rugged pattern in the direction traversing the extruding plastic flow (width direction) on the side face of a mouthpiece and 3 at the intersection 8 of the mouthpiece land 3 communicating to an extruder A and a mouthpiece land 4 communicating to an auxiliary extruder B. The rugged pattern is formed in such a manner that a tongued-and-grooved face gradually vanishes toward the inner part of the mouthpiece land 3. For example, only on the under surface of a block-shaped liner 5, which is fitted to the intersection 8 of the mouthpiece lands 3 and 4, tapered tongued parts 6 are formed. By meeting molten plastics sent from the main extruder and from the auxiliary extruder in a mouthpiece, a flat sheet-like double layer molded item having one of various kinds of rugged patterns, each of which is determined by the rugged pattern of the intersection, can be obtained. The formed rugged pattern does not vanish due to wear, because of being imbedded. |
