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:
Jul. 31, 2018
Filed:
May. 28, 2015
Sakai Chemical Industry Co., Ltd., Osaka, JP;
Toshikatsu Umaba, Osaka, JP;
Hiromitsu Shimizu, Osaka, JP;
Kenji Mori, Osaka, JP;
Keiichi Tabata, Osaka, JP;
SAKAI CHEMICAL INDUSTRY CO., LTD., Osaka, JP;
Abstract
The invention provides a polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or ester-forming derivative thereof and a glycol, wherein the polycondensation catalyst comprises particles of a solid base having on their surfaces either a coat layer of titanic acid in an amount of from 0.1 to 50 parts by weight in terms of TiOper 100 parts by weight of the solid base, or an inner coat layer of an oxide of at least one element selected from silicon, aluminum and zirconium or a composite oxide of at least two elements selected from silicon, aluminum and zirconium in an amount of from 1 to 20 parts by weight per 100 parts by weight of the solid base and an outer coat layer of titanic acid in an amount of from 0.1 to 50 parts by weight in terms of TiOper 100 parts by weight of the solid base, and wherein the solid base is hydrotalcite.