Process for producing polyalkylene terephthalate, process for producing polyalkylene terephthalate molding and polyalkylene terephthalate molding

Abstract

The present invention provides a method of producing polyalkylene terephthalate, which comprises: introducing a prepolymer of polyalkylene terephthalate that is in a molten state comprising 70 mol % or more of ethylene terephthalate or 1,4-butylene terephthalate repeating units and having an intrinsic viscosity [η] between 0.2 and 2 dl/g through a feed opening to a polymerization reactor; discharging the introduced prepolymer from holes of a perforated plate; and polymerizing the prepolymer under reduced pressure, while allowing the prepolymer to fall along the surface of a support that is open towards the outside at a temperature between the [crystalline melting point−10° C.] of the prepolymer or higher and the [crystalline melting point+30° C.] of the prepolymer or lower under the conditions represented by a formula S1/S2>1, wherein S1 is the surface area of falling polyalkylene terephthalate, and S2 is the area where the support is in contact with polyalkylene terephthalate.

Dependencies are inferred from the claim text.