| 摘要 |
<p>PURPOSE:To omit a drying process and also to obtain a plastic material efficiently which is almost free from water content by a method wherein a water-contained plastic is supplied to an extruding cylinder provided with exhaust ports at 3 spots, which is heated and then extruded. CONSTITUTION:An extruding screw 6 havig a shaft length about 40 times as long as the diameter, shaft diameters right beneath exhaust ports 3a, 3b, 3c which are smaller than ay other parts and heights of stirring vanes on said spots which are larger than any other parts is installed in an extruding cylinder 2 provided with said three exhaust ports 3a, 3b, 3c. The cylinder 2 is heated to about 400 deg.C, the screw 6 is turned at 55-100rpm, a plastic material 30-70% in water content is fed through a hopper 1, which is moved toward an extrusion port 4, as heated, by the screw 6. Then, the water content is eliminated at about 30% at the exhaust port 3a, at about 30% at the exhaust port 3b and further at about 10% at the exhaust port 3c, and thus the plastic material almost free from water content is extruded in a bar shape from the extrusion port 4.</p> |
