| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing, effectively and without lowering a polymerization rate, an aromatic polycarbonate excellent in hue, stability of hue, heat stability and further transparency. SOLUTION: Piping for pneumatically transporting powder of an aromatic dihydroxy compound, is made so as to satisfy R>=5 D (wherein D is inner diameter of pipe and R is radius of curvature), the number of bending parts of pipe of 50 or below and a total length of pipe of 500 m or below, when producing this aromatic polycarbonate by melt-polycondensation.
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