Process for the manufacture of carbamide and formaldehyde products in presence of sulphonated amide derivatives, and products obtained

摘要

Urea and formaldehyde are reacted in the presence of a sulphonated amide, preferably p-toluene-sulphonamide, and powdered zinc. During the primary condensation or before the reactants have boiled there may be added cheap soluble fillers, e.g. sugar refinery waste. The solution of condensate is filtered, slightly reheated if cloudy, and dehydrated, preferably under reduced pressure, until under constant pressure, the temperature of the syrup rises 4 to 5 DEG C. in 5 mins. The product is soluble in water, alcohol, ketones, amd hydrocarbons and may be plasticized by glycerol or ethylene glycol; it may be gelled by the addition of an organic acid or sa it may be used for the production of coatings which are finally hardened by spraying with ammonium phosphate solution, and of laminated blocks of resin alone or with glass, celluloid, or cellulose acetate. An Example is given. The Specification as open to inspection under Sect. 91 refers to the use, instead of metallic zinc, of a metal in pulverulent form, preferably one not causing colouration by oxidation or hydration. This subject-matter does not appear in the Specification as accepted.