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:
Dec. 18, 2001
Filed:
Feb. 28, 2000
Applicant:
Inventors:
Shoshiro Matsushita, Tokyo, JP;
Ikuo Shimizu, Yokkaichi, JP;
Hiroshi Toyoda, Yokkaichi, JP;
Asako Tanaka, Matsumoto, JP;
Assignee:
Kyowa Yuka Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 4/500 ;
U.S. Cl.
CPC ...
C07C 4/500 ;
Abstract
The present invention provides a method for manufacturing 3,4-dihydroxy-3-cyclobutene-1,2-dione represented by the following general formula (III) (usual name: “squaric acid”) through the following reaction processes 1˜4, using a vinyl ether represented by the following general formula (V) and a halogenoacetyl halide represented by the following general formula (VI) as starting materials.