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.

Abstract: The present invention relates to a new fertilizer compound of the ureaform type and to a method for the production thereof. The new ureaform compound is characterized by the low average degree of polymerization between urea and formaldehyde. The new compound has a nitrogen content of over 41% by weight and consists of cold water soluble nitrogen as the main fraction and cold water insoluble as the second fraction which is substantially free of hot water insoluble nitrogen. The new ureaform compound is obtained by the condensation of urea and formaldehyde at a correct ratio between the reagents and termination of the reaction at a stage wherein excessive polymerization is prevented. The reaction is carried out in a controlled system with a pH in the range of 3.5 to 4.2. Particularly useful are the systems 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.