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:
Mar. 03, 1998
Filed:
Nov. 15, 1995
The Dow Chemical Company, Midland, MI (US);
Abstract
A process for preparing an adduct of a bisphenol with a phenolic compound comprising the following steps: a) reacting a carbonyl compound with a stoichiometric excess of a phenolic compound in the presence of an acidic cation exchange resin as a catalyst, to produce a product mixture containing a bisphenol, unreacted phenolic compound, unreacted carbonyl compound and water, and b) crystallizing an adduct of the bisphenol with the phenolic compound from the product mixture in a crystallization device in the presence of water and acetone. The product mixture obtained in step a) is not subjected to a distillation step before the product mixture enters the crystallization device and prior to the crystallization step b) the content of the carbonyl compound in the product mixture is controlled and, if necessary, carbonyl compound is added such that the total concentration of the carbonyl compound is from about 0.1 to about 8 percent, based on the total weight of the product mixture.