公开(公告)号：JPH1135664A

公开(公告)日：1999-02-09

申请号：JP19564097

申请日：1997-07-22

Applicant: TORAY INDUSTRIES

Inventor： ITO SHIN ,  KATOU YOSHIMASA ,  MIYAGAWA HIROYUKI

IPC: C07C63/26 ,  C08G63/183

Abstract: PROBLEM TO BE SOLVED: To obtain terephthalic acid for producing the corresponding low- discolored polyester with stable color tone, and to provide a method for the above polyester. SOLUTION: The subject terephthalic acid has the following characteristics: the content of 9-fluorenone-2, 6-dicarboxylic acid is =87%; and the light transmittance (at 340 nm) of its alkali solution after heated at 280 deg.C for 3 h (concentration at 7.5 g/dL) (quartz cell, optical path length being 10 mm) is >=70%. The other objective polyester is obtained by esterification between the terephthalic acid and a glycol followed by conducting a polycondensation.

公开(公告)号：JPH1160714A

公开(公告)日：1999-03-05

申请号：JP22811497

申请日：1997-08-25

Applicant: TORAY INDUSTRIES

Inventor： ITO SHIN ,  KATOU YOSHIMASA ,  YOSHIOKA MASAO

IPC: C08G63/183 ,  C08G63/86

Abstract: PROBLEM TO BE SOLVED: To provide a method for producing a polyester solving problems comprising the variation in the polymerization degree of the polyester due to the change in a reaction rate and the generation of foreign matters due to the deposition of one or more metals, and thereby enabling to produce the polyester little in color and having a stable color tone. SOLUTION: This method for producing a polyester comprises subjecting terephthalic acid and ethylene glycol as main components to an esterification reaction and subsequently subjecting the esterification product to a polycondensation reaction. Therein, antimony trioxide having a purity of >=99.0% and containing lead element and bismuth element in amounts of 30-60 ppm and