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:
Jan. 17, 1989
Filed:
Apr. 21, 1988
Mitsui Toatsu Chemicals, Inc., Tokyo, JP;
Abstract
This invention relates to a process for preparing 2,2-bis(4-hydroxyphenyl)propane, e.g. bisphenol A and particularly to a process for preparing high quality bisphenol A with good workability by distilling the intermediate adduct of bisphenol A and phenol. The adduct of bisphenol A and phenol is fed to a distillation column. Phenol is recovered from the top of the column and bisphenol A is obtained from its bottom. In this distillation process, the adduct of bisphenol A and phenol is added with a part of recycled bottom liquid. Consequently troubles such as plugging of the distillation column are prevented, continuous operation becomes possible for a long period of time and high quality bisphenol A can be steadily obtained.