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:
Apr. 08, 2003
Filed:
Sep. 19, 2001
Gaylord Michael Kissinger, Evansville, IN (US);
Fang Christine Chen, Evansville, IN (US);
James Cristopher Blubaugh, Evansville, IN (US);
Darlene Hope Nance, Mt. Vernon, IN (US);
Edward Brittain Stokes, Schenectady, NY (US);
Juan Rodriguez Ordonez, Madrid, ES;
Jose M. Quintana, Murcia, ES;
General Electric Company, Schenectady, NY (US);
Abstract
Low-particulate dihydric aromatic compounds such as bisphenol-A that can be used in the synthesis of low-particulate polycarbonates are prepared by introducing into a desorber column containing a non-aggregate packing material an adduct of bisphenol and phenol and optionally a stripping gas. The column is maintained at an operating temperature that is sufficiently high and an operating pressure that is sufficiently low such that the adduct is distilled. The stream of phenol and the stripping gas is recovered from the top of the column. A second stream containing bisphenol that is substantially free of added particulate matter is recovered from the bottom of the column. This purified stream of bisphenol-A can further be used in a method of producing optical-grade polycarbonate.