| 摘要 |
PROBLEM TO BE SOLVED: To prevent a vascular injury and to enable a catheter to be left in a human body for a long period and to improve durability and safe thereof by forming a polyol from a polyurethane resin consisting of a polycarbonate, etc. SOLUTION: A polyol for this indwelling catheter is constituted of a polyurethane resin prepared from a polycarbonate, an isocyanate, and a chain extender. The hardness of the catheter is preferably in a range of Shore hardness A between about 50-D80. When the hardness is lower than the range, the catheter is too soft to be easily handled, and when higher, the catheter may cause danger of a tissue injury. A metal and a compound presenting X-ray impermeability, for instance gold, etc., are added as X-ray contrast agent to give the polyol X-ray impermeability to enable X-ray imaging. This constitution improves kinking resistance and, even when the catheter is folded at 180 deg., drip fusion is not stopped. The strength is not lowered in a severe aging test. Further, the catheter matches a safety test and a tube durability test. |
