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. 03, 2004
Filed:
Oct. 31, 2002
Kazuyuki Hirano, Chiba, JP;
Ken Fujimoto, Chiba, JP;
Idemitsu Petrochemical Co., Ltd., Tokyo, JP;
Abstract
Provided is a production process for high quality bisphenol A which is reduced in a sulfonic acid-containing heavy matter contained in the product and which is improved in a hue. In an after-treating step for a reaction mixed solution obtained by condensing excess phenol with acetone in the presence of an acid catalyst, a filtering step by a filter is provided at least in one step between a step for dissolving an adduct of bisphenol A and phenol by using a phenol-containing solution and a step for crystallizing and separating the above adduct from this solution.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile