The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 06, 2011
Filed:
Oct. 07, 2004
Hiroshi Yokoyama, Okayama, JP;
Katsuhiro Fujimoto, Yokohaya, JP;
Muneaki Aminaka, Okayama, JP;
Junichi Sugimoto, Nishitokyo, JP;
Tsutomu Katsumata, Yokohama, JP;
Hiroshi Yokoyama, Okayama, JP;
Katsuhiro Fujimoto, Yokohaya, JP;
Muneaki Aminaka, Okayama, JP;
Junichi Sugimoto, Nishitokyo, JP;
Tsutomu Katsumata, Yokohama, JP;
Asahi Kasei Chemicals Corporation, Tokyo, JP;
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 S/S>1, wherein Sis the surface area of falling polyalkylene terephthalate, and Sis the area where the support is in contact with polyalkylene terephthalate.