| 摘要 |
PROBLEM TO BE SOLVED: To improve a beautiful pearly glossiness having smoothness, anisotropy, much rain cloud-like change and extreme decorativeness by regulating a transesterification rate of a polyethylene terephthalate resin and a polyethylene naphthalate resin in a specific range, and injection molding it. SOLUTION: A transesterification rate of a polyethylene terephthalate resin and a polyethylene naphthalate resin is desirably regulated to 3 to 30% or preferably 5 to 20% with that at the time of advancing the rate theoretically by 100% as a base. If the rate is less than 3%, or less than 5%, it is necessary to lower a resin temperature at the time of molding under a molding condition. As a result, the polyethylene terephthalate is not completely melted, but molded as unmelted. If the rate exceeds 20%, or further 30%, severe molding condition such as an excess kneading of the rein or raising of the resin temperature must be executed. |
