| 摘要 |
PURPOSE:To give numerous fine unevennesses to the internal surface of a tubular molded piece and prevent the internal surfaces from sticking closely to each other by extruding and molding thermoplastic resin cooling the internal die or an extruding machine. CONSTITUTION:Melted resin 16 is extruded and molded into a tubular state with an extruding machine composed of an external die 10 and an internal die 12 having a cooling fluid passage 4 and said pool section 13. The melted resin is cooled by the internal die to provide numerous fine unevennesses 17 on its internal surface. Even though the internal surfaces are brought by load or bending, etc. into contact with each other for a long period of time, both surfaces are not stuck and peeled because of their unevennesses. This material is especially suitable for a blood bag or a blood tube. |
