| 摘要 |
PURPOSE:To prevent resin from coloring such as yellowing even if a molding condition or a resin component is varied to some extent, by making use of a molding machine possessing a cylinder and screw constituted of the specific quality of the material. CONSTITUTION:The title method is constituted so that at the time of extrusion molding or injection molding of polycarbonate resin, the quality of the material of the surface of a resin contacting part of at least a cylinder or a screw of a molding machine is constituted of titanium carbide, titanium nitride and either of a nickel alloy presented by the following alloy composition A or B. The alloy composition A is constituted of 50-80wt.% nickel 7-18wt.% chromium, 2-6wt.% silica, 0.1-20wt.% cobalt, 2-6wt.% boron and 3-8wt.% iron and the alloy composition B is constituted of 50-80wt.% nickel, 7-18wt.% chromium, 2-6wt.% silica, 0.1-20wt.% cobalt, 2-6wt.% boron, 3-8wt.% iron, 0.1-2wt.% mangan and 0.1-0.5wt.% carbon. |
