Screw for kneading and single screw extruder

摘要

PROBLEM TO BE SOLVED: To improve kneading and suppress shear heating of a resin during high speed kneading in the kneading of a resin composition by a single screw extruder.SOLUTION: In a screw for a single screw extruder, a plurality of helical flights and grooves are provided, the helical groove is provided with a raised projection extending over the groove width direction from the bottom surface of the helical groove, the oblique line of the projection corresponding to a slant face rises in a concave shape from the bottom surface of the groove toward the top of the projection in a cross-sectional shape formed by cutting the projection perpendicular to the bottom surface of the groove in the helical direction, and the width of a top portion of the projection is not more than 0.3 times the outer diameter of a screw.SELECTED DRAWING: Figure 6