In order to prevent discharge being produced from an outlet when performing extrusion molding over extended periods of time, a shell (2), formed with an outlet (3) through which a melt-kneaded resinous material is extruded by an extruder, is detachably fitted with a plate-like shell tip (6) forming an opening (7) that is disposed along and surrounds the circumference of the outlet (3), and a non-adhesive coating is applied at least along the inner circumference of the opening (7) formed by the shell tip (6).
