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:
Feb. 18, 2014
Filed:
Apr. 05, 2007
Shinya Konuma, Matsuyama, JP;
Shinya Konuma, Matsuyama, JP;
Teijin Fibers Limited, Osaka, JP;
Abstract
A manufacturing method of polyethylene terephthalate including a step of melt polycondensation in presence of polycondensation catalyst represented by general Formula (I), wherein Rrepresents an alkyl group having from 2 to 12 carbon atoms, and melt polycondensed polyethylene terephthalate has an intrinsic viscosity of from 0.48 to 0.53 dL/g and a terminal carboxyl number of from 14 to 22 mmol/kg; and a step of solid phase polycondensation to obtain solid phase polycondensed polyethylene terephthalate having an intrinsic viscosity of from 0.70 to 0.86 dL/g, and a terminal carboxyl number of less than 15 mmol/kg, followed by a step of applying an aqueous solution of at least one salt selected from the group consisting of acetate, carbonate, and sulfate of sodium, potassium, or cesium to the solid phase polycondensed polyethylene terephthalate, and then drying the polyethylene terephthalate, wherein the final content of sodium, potassium or cesium atom in dried polyethylene terephthalate is from 2 to 25 ppm.