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. 24, 1992
Filed:
Jan. 31, 1991
Ronald S Bauer, Houston, TX (US);
Kailash C Dangayach, Houston, TX (US);
Shell Oil Company, Houston, TX (US);
Abstract
A process is disclosed for preparing a low-chlorine tetrafunctional epoxy resin which employs crystallization of the epoxy resin from solution in a finishing step of the preparation process. The process involves (a) contacting, in a basic reaction medium, epichlorohydrin and a tetraphenol of ethane to produce a reaction product mixture containing a polyglycidyl ether of the tetraphenol of ethane; (b) dissolving the polyglycidyl ether in an organic solvent and, optionally, contacting the polyglycidyl ether with a dehydrochlorination agent; and (c) reducing the temperature of the organic solvent so as to effect crystallization of a low-chlorine fraction of the polyglycidyl ether.