Abstract: An endoscope flexible tube comprises: a tubular structure having flexibility; and a shell layer on an outer peripheral surface of the tubular structure, wherein the shell layer has a two-layer structure including a rigid resin layer of a rigid resin and a soft resin layer of a soft resin, and wherein the two-layer structure is maintained over the entire flexible tube in its length direction.

Abstract: A method for producing a flexible tube device includes supplying a tubular structure to an extrusion head, extruding a molten rigid resin and a molten non-rigid resin at a constant pressure to the tubular structure through an orifice formed in the extrusion head, controlling a moving speed of the tubular structure when extruding the molten rigid resin such that the moving speed becomes a highest speed VH when the proximal end passes through the orifice, and decreases at a first constant acceleration rate until a first change point, located closer to the proximal end than to the distal end, passes through the orifice to reach a lowest speed VL, controlling the moving speed of the tubular structure when extruding the molten non-rigid resin, and cooling the tubular structure to obtain the flexible tube device.

Abstract: A flexible tube device has proximal and distal ends, for attachment of the proximal end to a handle assembly of an endoscope. The flexible tube device includes a spiral pipe formed by helically winding an elongate strip of metal. A tubular mesh material is disposed around the spiral pipe. A jacket material is disposed around the tubular mesh material, and formed from rigid resin and non-rigid resin. In the jacket material, a content of the non-rigid resin is higher than a content of the rigid resin at the proximal end. The content of the rigid resin gradually increases from the proximal end toward a first change point predetermined nearer to the proximal end than to the distal end. The content of the rigid resin is higher than the content of the non-rigid resin at the first change point.

Abstract: An endoscope flexible tube comprises: a tubular structure having flexibility; and a shell layer on an outer peripheral surface of the tubular structure, wherein the shell layer has a two-layer structure including a rigid resin layer of a rigid resin and a soft resin layer of a soft resin, and wherein the two-layer structure is maintained over the entire flexible tube in its length direction.