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. 22, 2007
Filed:
Jul. 24, 2002
Applicants:
Hirofumi Shiigi, Yamaguchi, JP;
Eiji Ohshima, Yamaguchi, JP;
Masao Yamaguchi, Yamaguchi, JP;
Inventors:
Assignee:
Tokuyama Corporation, Yamaguchi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
V07C 51/56 (2006.01);
U.S. Cl.
CPC ...
Abstract
According to the present invention there is provided a process for producing an acid anhydride by reacting a carboxylic acid, preferably a carboxylic acid having a polymerizable group, with a sulfonyl halide compound in the presence of a tertiary amine or in the presence of a tertiary amine and an inorganic base, wherein the tertiary amine or the tertiary amine and the inorganic base are used in an amount of 0.9 to 1.2 equivalents relative to the acid generated from the sulfonyl halide compound.