Patent GB-953754-A (GB)
Title: Improvements in and relating to water-soluble condensation products of urea and formaldehyde
Inventor: MAWSON JACK FRANKLAND
IPC: C08G12/12
Filed: 1961-05-10
Abstract: Aqueous solutions of stable, water-soluble condensation products of urea and formaldehyde are prepared by mixing urea (1 mole) and formaldehyde (3.5 to 10 moles) in an aqueous medium containing sufficient base to give a pH of 7.3 to 10, maintaining the mixture at a temperature of 10 to 25 DEG C., for 1 to 8 hours, and then heating the mixture at 50 to 90 DEG C., for 15 minutes to 2 hours.  The condensation products may be modified by etherification with a monohydric alcohol having less than 5 carbon atoms at a pH of 3.5 or less. The etherification may be carried out in aqueous solution. Bases specified are ethanolamine and sodium hydroxide with or without buffering mixtures of salts such as the sodium, potassium and/or ammonium salts of phosphoric, boric or carbonic acid. The products may be cured by means of acid or latent acid curing catalysts e.g. ammonium dihydrogen phosphate, ammonium thiocyanate, ammonium nitrate, zinc chloride, zinc nitrate hexahydrate, magnesium chloride, tartaric and maleic acids, butanolamine hydrochloride and diethanolamine hydrochloride or mixtures thereof.  The aqueous solutions are useful in treating textiles and may also contain other aminoplasts such as the methylol derivatives, and their ethers, of thiourea, substituted ureas and thioureas, imidazolidones, dicyandiamide, carbamates, allophanates, ureins, urono, triazones, aminotriazines and stearamide; polyvinyl alcohol; cellulose ethers; starches; starch ethers; casein; gelatine; polyvinylacetate; polyethylene; sodium (tri) isopropyl naphthalene sulphonate, condensates of octylphenol with ethylene oxide and reactive dyestuffs. Examples are given of the condensation of urea and formaldehyde, in the presence of sodium hydroxide and sodium dihydrogen phosphate; of the etherification of the products with methanol and hydrochloric acid followed by basification of the mixture with caustic soda solution, distillation under reduced pressure of excess methanol and water, addition of sodium borate solution and adjustment of the pH with hydrochloric acid.  In one example a condensate of urea and formaldelyde is prepared, melamine ethanol and aqueous formaldehyde are added, the pH is adjusted to 6.3, the mixture is heated under reflux, cooled, basified with caustic soda.  The resultant mixture is distilled under reduced pressure and to the residue are added isopropanol, water, borax and caustic soda.  Specifications 785,120, 785,222, 835,596, 846,505, 888,905 and 947,222 are referred to.ALSO:Cellulosic textiles, e.g. cotton, viscose rayon and linen, may be made crease-resistant by treating them with aqueous solutions of stable water-soluble condensation products of urea (1 mole) and formaldehyde (3.5 to 10 moles) prepared in an alkaline medium in two stages (see Division C3).  The condensation products may have been etherified.  The solutions may contain curing agents, e.g. ammonium dihydrogen phosphate, ammonium thiocyanate, ammonium nitrate, zinc chloride, zinc nitrate hexahydrate, magnesium chloride, tartaric and maleic acids, butanolamine and diethanolamine hydrochlorides, or mixtures thereof; other aminoplasts such as the methylol derivatives, and their ethers, of thiourea, substituted ureas and thioureas, imidazolidones, dicyandiamide, carbamates, allophanates, ureins, triazones, aminotriazines and stearamide; polyvinyl alcohol; cellulose ethers; starches; starch ethers; casein; gelatine; polyvinyl acetate; polyethylene; sodium (tri) isopropylnaphthalene sulphonate; condensates of octyl phenol with ethylene oxide and reactive dyestuffs.  In examples mercerized cotton poplin and viscose rayon fabrics are treated with the compositions by immersion or padding, squeezed to remove excess of the solution and heated to cure the condensation product.  Specifications 785,120, 785,222, 835,596, 846,505, 888,905 and 947,222 are referred to.