| 摘要 |
PURPOSE:To remove liquid color quicker and surer and consequently contrive to enhance the production efficiency of the title molder by a method wherein the operation, in which a screw plunger is continuously rotated at the advanced position under large back pressure so as to push out raw material resin and, after that, also continuously rotated as is held at the retreated position under large back pressure so as to push out raw material resin, is repeated. CONSTITUTION:After the molding by injecting raw material resin 3, which is added with liquid color having the predetermined color and supplied in a cylinder 7, with a screw plunger at the previous stage is finished, firstly, a screw plunger 6 is continuously rotated at the advanced position under large back pressure so as to push out raw material resin 3. Secondly, the rotation of the screw plunger 6 is stopped and the stopped plunger is retreated by sliding within the cylinder 7. Thirdly, the screw plunger is continuously rotated as is held at the retreated position under large back pressure so as to push out the raw material resin 3. Finally, the screw plunger 6 is returned to the predetermined position in order to finish a color change process. Said color change process is repeated a set number of turns. Thus, the liquid color is removed quickly and surely and the loss of used raw material is reduced and, at the same time, the shortening of color change time is contrived. |
