| 摘要 |
PURPOSE:To obtain a hollow body made of synthetic resin which is excellent in the characteristics of both flexibility and mechanical strength and also excellent in dimensional precision of an internal surface. CONSTITUTION:Two semicylindrical cross-sectional curved members (split members) 1a, 1b are prepared by integrally forming rigid resin parts and soft resin parts 3 in the circumferential direction by injection molding. The cross-sectional curved members 1a, 1b correspond to the shapes wherein a hollow body made of synthetic resin is divided into two in the axial direction. The hollow body is obtained by joining and integrating the end faces in the circumferential direction of the cross-sectional curved members 1a, 1b by thermally melt- sticking. Since the rigid resin parts 2 and the soft resin parts 3 are formed in the circumferential direction, the hollow body is excellent in flexibility and mechanical strength. Further even when pressure acts on the joined end faces in the case of thermally melt-sticking, it can be inhibited by the rigid resin parts 2 formed in the circumferential direction that the soft resin parts 3 are swelled to the inner part of the hollow body. |
