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:
Nov. 06, 1979
Filed:
Mar. 26, 1976
Dahlia S Greidinger, Haifa, IL;
Liuba Cohen nee Girshowitsh, Haifa, IL;
Shimon Epstein, Kiryat Motzkin, IL;
Fertilizers & Chemicals Ltd., Haifa, IL;
Abstract
The present invention relates to a method for the manufacture of an improved ureaform fertilizer. The method consists in the condensation of urea and formaldehyde carried out in a controlled system having a pH between 3.5 and 4.2 wherein the overall concentration of the reagents is in the range of 20 to 40% by weight. The ratio between the reagents is between 1.2 to 1.5 moles of urea to 1 mole of formaldehyde and the temperature of the reaction is kept between 15.degree. C. to 40.degree. C. Examples of preferred controlled systems are H.sub.3 PO.sub.4 -KH.sub.2 PO.sub.4 and H.sub.3 PO.sub.4 -NH.sub.4 H.sub.2 PO.sub.4. The method can also be performed in a continuous manner giving rise to an overall quantitative yield, and being temperature self-regulating. The ureaform obtained by the method has an activity index of over 75 and excellent physical properties.