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:
Oct. 08, 2002
Filed:
May. 26, 2000
Akira Yamashita, Arai, JP;
Mitsuhiro Kouno, Arai, JP;
Daicel Chemical Industries, Ltd., Osaka, JP;
Abstract
The invented process produces sorbic acid. The process includes the steps of adding a crude sorbic acid to a hot water having a temperature exceeding 100° C., which crude sorbic acid is obtained by the decomposition of a polyester formed through a reaction of ketene with crotonaldehyde, and performing at least one treatment selected from (A) a hot water extraction treatment for extracting sorbic acid with the hot water, and (B) a treatment with an activated carbon in the hot water. The temperature of the hot water is, for example, 120° C. or lower. The amount of sorbic acid to be treated is, for example, equal to or less than the saturated dissolution amount of sorbic acid with respect to the hot water at a treating temperature. The invented process can easily and efficiently remove tar substances and other impurities by-produced in the decomposition of the polyester and can produce a highly purified sorbic acid with a high productivity.