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:
Sep. 14, 2004
Filed:
Apr. 23, 2001
Gerhard Coufal, Leonding, AT;
Agrolinz Melamin GmbH, Linz, AT;
Abstract
The invention relates to a method for producing pure melamine. According to this method, the melamine melt, which is produced from urea in a high-pressure process, is cooled and ammonia is added until it reaches a temperature of approximately 1 to 50° C. above the melting temperature of the melamine as dependent on the respective pressure of ammonia and then either a) quenched with water or an aqueous solution or suspension containing ammonia and/or melamine so that the melamine solidifies or b) quenched with cold liquid or gaseous ammonia, so that the melamine solidifies, the melamine then being cooled further with water or an aqueous solution or suspension containing ammonia and/or melamine and c) the melamine is then isolated.