FLEXIBLE TUBE FOR ENDOSCOPE AND METHOD FOR MANUFACTURING THE SAME

摘要

In a flexible tube (10) for an endoscope, an outer coating layer (15) is coated on the outer peripheral surface of a flexible tube base (14). The outer coating layer (15) has a soft resin layer (17) and a hard resin layer (18). The outer coating layer (15) has a tapered portion (15a) and the large diameter portion (15b). The large diameter portion (15b) has a ratio changing portion (15c). In the ratio changing portion (15c), the thickness of the soft resin layer (17) increases gradually and the thickness of the hard resin layer (18) decreases gradually from the proximal end (14a) side toward the distal end (14b) side of the flexible tube base (14). The tapered portion (15a) has the same thickness ratio as that at a position in the ratio changing portion (15c) where the percentage of the thickness of the hard resin layer (18) is a lower limit. In addition, the outer diameter of the tapered portion (15a) decreases gradually toward the distal end (14b) side of the flexible tube base (14) while maintaining the same thickness ratio as the ratio fixed portion (15e), and the minimum outer diameter position matches the distal portion of the flexible tube base (14).