PROBLEM TO BE SOLVED: To provide a tube having both flexibility and rigidity, and excellent in kink resistance for improving flexibility while keeping rigidity to various bending radiuses.SOLUTION: In at least a part in a lengthwise direction, full structure parts 2 and porous structure parts 3 are alternately constructed. It is preferable that a specific gravity of the full structure part is 0.80-2.20, a specific gravity of the porous structure part is 0.10-2.00, and a ratio (porous structure part/full structure part) of the specific gravity of the full structure part to the specific gravity of the porous structure part is 0.05-0.95.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2020,JPO&INPIT【課題】柔軟性と剛性を兼ね備え、様々な屈曲半径に対して剛性を維持しつつ柔軟性を改善する耐キンク性に優れるチューブを提供する。【解決手段】長さ方向の少なくとも一部において、充実構造部２と多孔質構造部３が、交互に構成されていることを特徴とする。充実構造部の比重が、０．８０～２．２０、多孔質構造部の比重が、０．１０～２．００、充実構造部における比重と、多孔質構造部における比重との比率（多孔質構造部／充実構造部）が、０．０５～０．９５であることが好ましい。【選択図】図１
