| 摘要 |
PROBLEM TO BE SOLVED: To easily and inexpensively produce a surgical tube having a soft front end. SOLUTION: The dural surgical catheter 1 having the soft distal end 2 is formed by co-extrusion molding of an inner layer 11 and an outer layer 12. The inner layer is molded of plastic softer than the outer layer. An extruder 20 has two extrusion heads. The extrusion head for the inner layer 11 has a mobile cone and periodically moves this mobile cone to increase the bore of the inner layer, then to completely shut off the flow of the extrudate. As a result, regions 13 having portions 14 where the inner layer 11 is made thin and portions 15 where there is no inner layer are formed. A tubular molding is cut at the ends of these regions 13 and thereafter the ends are closed to form lateral openings 3, by which the patient side distal end 2 is provided with the rigidity lower than the rigidity of the remaining part of the catheter 1. |
