| 摘要 |
PURPOSE:To obtain a molded form having excellent characteristics by low warpage and low post-shrinkage by injection molding melamine resin molding material in a range of a specific mold temperature. CONSTITUTION:A method for manufacturing a melamine resin molded form comprises the step of injection molding a melamine resin molding material at a mold temperature of 200-250 deg.C. Normally, the mold temperature of an injection molding machine at the time of injection molding the material is about 165-175 deg.C, but it is raised to 200-250 deg.C thereby to obtain a molded form having excellent characteristics such as low warpage and low post-shrinkage. As to the warpage, it is evaluated by an orientation difference of a difference of molding shrinkages between a parallel direction and a perpendicular direction, and small numeric value is excellent. This shrinkage factor is measured based on JIS K 6911. The orientation difference is about 0.2% at the time of 165-175 deg.C of the mold temperature of the machine, and when it is set to about 200-250 deg.C, it becomes about 0.01-0.06%. |
