GB483399A - Improvements in or relating to resinous condensation products - Google Patents

Abstract

Urea (including alkyl-, acyl- and aryl-ureas, thiourea, guanidine and substituted guanidine), formaldehyde and more than one molecular proportion of a primary aliphatic four-carbon alcohol (such as butyl and iso-butyl alcohol) for each molecular proportion of urea are condensed, the water formed in the reaction being removed by distillation until substantially two molecules of water for each molecule of urea are eliminated. Catalysts such as phthalic anhydride, maleic acid, adipic acid, citric acid, rosin, alkyd resins, hydrochloric acid, sulphuric acid, phosphoric acid, mercuric chloride, aluminium chloride or stannic chloride, iodine, bromine or benzoylperoxide may be used. Distillate other than water, separation of which may be facilitated by an entraining agent, is returned to the reaction. In examples: (1) a mixture of N-butyl alcohol, paraformaldehyde and caustic soda is warmed, mixed with phthalic anhydride, urea and toluene and the mixture heated and distilled, the distillate, less the water contained in it, being returned to yield a resin solution; (2) a mixture of aqueous formaldehyde, sodium acid phosphate and sufficient sodium hydroxide to yield a pH of 7,6 is mixed with urea and allowed to stand to obtain a crystalline methylol compound which is then mixed with isobutyl alcohol, toluene and phthalic anhydride and heated and distilled to yield a resin solution. The products may be blended with other materials such as alkyd resins, oleo-resinous varnishes, cellulose derivative lacquers, oils, waxes, natural resins (congo, copal and Damar), plasticizers (dibutyl or dicyclohexyl phthalate, tricresyl or triphenyl phosphate, camphor, ethyl or butyl tartrate or lactate), pigments, dyes or fillers. The products may be used as coating-compositions for metal, wood, glass, rubber, moulded plastic or synthetic resin products; to coat or impregnate fabric, woven fabrics of cotton, wool, silk and rayon, paper, leather, cellulose sheet (in the manufacture of shower curtains, glazed chintzes, raincoats and capes, tobacco pouches, glazed cambric for insulation, water-and greaseproof wrapping material, floor coverings and diaphragms); to impregnate and insulate electric coils; as an adhesive; and as a stiffening agent for felt or straw. The Specification as open to inspection under Sect. 91 refers in general to the polymerization of a urea, an aldehyde and an alcohol. This subject-matter does not appear in the Specification as accepted.