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. 03, 2012
Filed:
Sep. 05, 2006
Applicants:
Hideki Okada, Saitama, JP;
Tohru Tanaka, Tokyo, JP;
Takeshi Nomura, Tokyo, JP;
Inventors:
Assignee:
Cosmo Oil Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 227/00 (2006.01); C07C 229/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method for producing crystals of 5-aminolevulinic acid hydrochloride wherein, in carrying out adsorption of 5-aminolevulinic acid contained in a crude 5-aminolevulinic acid solution by a cation exchange resin and its subsequent desorption with an aqueous solution containing ammonium ion, a high purity 5-aminolevulinic acid aqueous solution is obtained using a change in electric conductivity or pH of the desorption liquid as the index, and chloride ion is added to the aqueous solution which is then mixed with an organic solvent.