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:
May. 17, 2016
Filed:
Aug. 18, 2014
Sabic Innovative Plastics Ip B.v., Bergen Op Zoom, NL;
Venkata Rama Narayanan Ganapathy Bhotla, Bangalore, IN;
Balakrishnan Ganesan, Bangalore, IN;
Kishan Gurram, Bangalore, IN;
Salkod Parameshwar Mallika, Bangalore, IN;
Arun Satyanarayana Kumar, Bangalore, IN;
Shubashree Swaminathan, Bangalore, IN;
Abstract
Disclosed herein is a method for producing a purified 2-aryl-3,3-bis(4-hydroxyaryl)phthalimidine of formula (I) wherein Ris hydrogen or a Chydrocarbyl group and Ris a hydrogen, a Chydrocarbyl group, or a halogen, and wherein the method comprises dissolving a crude phthalimidine compound in an aqueous base solution; precipitating the dissolved, crude phthalimidine compound from the aqueous base solution by adding an acid in an amount effective to lower the pH of the solution to 9.0 to 12.0, to provide a semicrude phthalimidine compound; and isolating the semicrude phthalimidine compound from the aqueous base solution, to provide the purified 2-aryl-3,3-bis(4-hydroxyaryl)phthalimidine of formula (I), and having a phenolphthalein compound content of less than 2,500 ppm, based on the weight of the purified 2-aryl-3,3-bis(4-hydroxyaryl)phthalimidine. Subsequent trituration with aqueous methanol and recrystallization from isopropanol can result in product having levels of phenolphthalein derivatives that are not detectable.