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:
Jun. 08, 1999
Filed:
Apr. 21, 1998
Atsushi Endo, Tokyo, JP;
Yasumasa Suda, Tokyo, JP;
Abstract
A process for the production of copper phthalocyanine, which overcomes the defect of a method using two reaction steps that since phthalimide formed in the first step adheres to the wall of a reactor and a stirring blade, the reaction in the second step does not smoothly proceed, so that the yield and the purity of the resultant pigment are low, and which process enables the industrially stable production of highly pure copper phthalocyanine at high yields, the process comprising the steps of (A) reacting phthalic anhydride or a phthalic anhydride derivative with ammonia to form phthalimide, (B) adding part or all of urea to the phthalimide obtained in step (A) and melting the mixture under heat to form a homogeneous slurry, and (C) adding copper or a copper compound and remaining urea if any to the slurry obtained in step (B) and forming a copper phthalocyanine or a copper phthalocyanine derivative in the presence of a catalyst.