Societa' Italiana Resine S.i.r. S.p.a.

Silvestro Pezzoli

Silvio Vargiu

Beppino Passalenti

Giancarlo Rossi

Giorgio Mazzoleni

Aqueous solutions of phenol and formaldehyde are stabilized with at least one carbohydrate such as saccharose, glucose, fructose, maltose, starch hydrolysates or molasses. The solutions are condensable and usable for preparing A-stage phenolic resin (resols).

Concentrated aqueous solution of phenol and formaldehyde stable at low

A hardenable composition comprising an unsaturated epoxy ester resin and an ethylenically unsaturated monomer copolymerizable with the latter, said monomer being present in the composition in an amount of from 0.4 to 2 parts by weight for each part by weight of said resin, and said resin being the reaction product of an unsaturated monocarboxylic acid or a monoester of an unsaturated bicarboxylic acid with the epoxidation product of epichlorohydrin and a novolak phenolic resin of the structural formula: ##STR1## wherein R is an alkyl radical containing from 1 to 10 carbon atoms, the methylene bridges being bonded to the central phenol ring in the ortho- positions in relation to the hydroxyl group, and to the other phenol rings in the ortho- or para- positions in relation to the hydroxyl groups.

Hardenable compositions comprising an unsaturated epoxy ester and an

Fertilizers with a slow and controlled release of nitrogen are obtained by condensing urea with formaldehyde in three condensation stages carried out under well-determined conditions of pH, temperature and formaldehyde/urea molar ratio and up to well-determined viscosities of the resulting product. The first stage is carried out in the presence of methanol, the second stage after addition of formic acid and the third stage after neutralization and addition of a further amount of urea. The condensation stages are followed by a terminal heat-treatment at 200.degree.-400.degree. C for 0.5 to 5 minutes.

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Biassono (Milan), Italy

Silvestro Pezzoli