| 摘要 |
PURPOSE:To improve yields with a reduction in the rejection rate due to mixing of color by extruding and cleaning a resin material preceding a color change remaining in a molding machine with an affiliated resin material virtually the same in the color as the resin material yet to be changed in the color with a higher viscosity than it. CONSTITUTION:In the process wherein a high-cycle resin material blended with a coloring agent is molded with an injection molding machine or the like to manufacture a colored resin molding, when the need arises for changing color, a resin material for extrusion cleaning blended with so as to be virtually the same in the color as a high-cycle resin material yet to be changed in the color is molded and extruded with the molding machine to clean. The molding using the extrusion cleaning resin material is repeated until the high cycle resin material preceding the projected color change can be removed. Normally, its repetition is enough if producing moldings three to five times. Then, the high-cycle resin molding material changed in color is molded to manufacture colored resin moldings in varied colors. This method is applicable for the color change for every available colored resin moldings. In resin parts of automobiles, for example, it is applicable for molding of bumpers, trims, instrument panels and the like. |
