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. 19, 1978
Filed:
Mar. 30, 1977
Applicant:
Inventors:
Assignee:
Ciba-Geigy Corporation, Ardsley, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
26032626 ; 26032641 ; 2603 / ; 546281 ; 546308 ; 546309 ;
Abstract
The invention relates to the improvement of the conventional processes for manufacturing monomaleimides and polymaleimides, in which it is known to cyclodehydrate corresponding monomaleamic or polymaleamic acids in the presence of acetic anhydride and tertiary amines. According to the invention, the tertiary amines are used only in very small amounts (0.1 to 0.5 mole per mole of maleamic acid group) and the dehydration is carried out at temperatures between 10.degree. and 50.degree. C. The end products are obtained in purer form and greater yield than in conventional processes.