| 摘要 |
PROBLEM TO BE SOLVED: To provide a high speed manufacturing method of a preform for a hollow shaped body hardly generating aldehydes during shaping, and showing excellent transparency, little variation of transparency and excellent dimensional stability, to provide a manufacturing method of a polyester stretched body using the preform and to provide a polyester shaped body obtained by using the preform. SOLUTION: The manufacturing method of the polyester preform obtained by shaping a polyester composition containing at least two polyesters as major components, these having substantially same composition but having different limiting viscosities, is characterized in that the difference of the limiting viscosities between the polyesters is 0.05 to 0.30 dl/g, the average weight (W) of each polyester chip is 5 to 50 mg, the ratio of the average weight (W) of the chips is 1.00 to 1.30, the difference of the crystallization degree between the polyesters is 10% or less, and dispersion ratio Mz/Mn of molecular weight distribution of the polyester composition is not less than 3.90. COPYRIGHT: (C)2006,JPO&NCIPI |
