| 摘要 |
PURPOSE:To obtain a desired sack, the surface of which is covered by fabric material, by a method wherein the fabric material excellent in stretchability is arranged onto the outer periphery of molten parison and the parison together with the fabric material is pinched by splits in order to blow compressed air in said parison. CONSTITUTION:Firstly, tubular molten parison 1, which is made by extruding heated and molten thermoplastic resin with an extruder, is positioned in splits 2 and 3 opposite to each other. At this time, fabric material excellent in stretchability is arranged onto the whole or at least onto some part of the outer periphery of the parison 1. Secondly, a compressed air injecting device 5 is set on the predetermined position of the parison 1 and then the splits 2 and 3 are closed. After that, compressed air is blown in the parison 1 so as to push the parison 1 and the fabric material 4 against the inner surfaces of the splits 2 and 3 in order to weld the parison 1 and the fabric material 4 integrally. Due to the method as mentioned above, the desired synthetic resin sack, the surface of which is covered by fabric material, can be manufactured. |
