| 摘要 |
<p>PURPOSE:To obtain 3-layered synthetic resin film or sheet very simply by a method wherein the conventional extrusion molding device for 2-layered synthetic resin film or sheet is employed and a gap is provided. CONSTITUTION:Blue resin, for example, entered from an entrance flow path 4 enters into the flow path 12 through the flow path 7 and ascends through the flow path 11. On the other hand, the most of red resin, for example, which has come from the entrance flow path 5 enters into the flow path 15 through the flow path 8 but a part of it enters into the gap 6. When a proper pressure difference is given to the resins entering through the entrance flow paths 4, 5, the resin, in which the red resin, entered from the flow path 15 and entered into the flow path 7 through the gap 6, is adhered as a layer to the outside of the layer of blue resin, flowing to the flow paths 12, 11 through the flow paths 4, 7 in a tubular condition, flows into the flow path 18. The red resin, entered through the flow paths 5, 8, 15, becomes a layer having red color only, ascends through the flow path 14, joins with the two-colored layer from the flow path 11 at a joining point (a) and becomes three layers, thereafter, a tubular three-layered resin 22 is extruded out of an exit flow path 18. The tubular resin 22 becomes three-layered resin having red shade in the outer layer 23 and the inner layer 24 and blue shade in the intermediate layer 25 thereof.</p> |
