Patent GB-703083-A (GB)
Title: Aminoplastic condensation products for treating fibrous material
IPC: D06M15/39
Filed: 1951-01-19
Abstract: Aminoplastic condensates are prepared by using as the aldehyde component an aliphatic aldehyde containing one or more methylol groups, e.g. trimethylolacetaldehyde, dimethylolpropionaldehyde and methylolisobutyraldehyde.  Specified amino compounds are urea, thiourea, dicyandiamide, guanidine, aminotriazines (e.g. melamine), aminodiazines (e.g. acetoguanamine), amino-quinazolines and guanazoles.  The condensates are used for impregnating or coating fibrous material, e.g. paper (see Group VIII), or textile fabrics (see Group IV (c)).  The condensates may be etherified with mono- or poly-hydric alcohols and then co-condensed with polyester resins.  In examples, (1) (a) Melamine is heated with trimethylol acetaldehyde in presence of caustic soda together with sodium carbonate or triethanolamine.  (b) Solutions of mono- and hexa - (- beta - trimethylol - alpha - hydroxyethyl)-melamine are prepared from 1 mol. of melamine and 1 and 6 mols. of trimethylolacetaldehyde.  (c) Urea and trimethylolacetaldehyde are condensed.  The condensates are used for treating rayon, with or without glycollic acid and may be stabilized with pyridine, piperidine or an ethanolamine.  (2) Acetoguanamine is heated with trimethylolacetaldehyde in presence of caustic soda and the alkalinity is maintained during the process by adding sodium carbonate.  An aqueous solution of the condensate and formic acid is used to impregnate rayon.  (3) Melamine is condensed with trimethylolacetaldehyde in presence of caustic soda and the alkalinity maintained by adding sodium carbonate.  A colloidal solution of the condensate in water and ethyl alcohol is added to paper pulp.  (4) Melamine is heated with trimethylolacetaldehyde, caustic soda and then sodium carbonate added and the temperature maintained at 80 DEG  C.  The product is added to paper pulp.  (5) Dicyandiamide is condensed with trimethylolacetaldehyde in presence of sodium carbonate.  The product is added to paper pulp.  The invention of Specification 682,406 is disclaimed.ALSO:Mono- and hexa-(-beta-trimethylol-alpha-hydroxyethyl)-melamine are prepared from 1 mol. of melamine and 1 or 6 mols. respectively of trimethylol - acetaldehyde.  The products are used to treat rayon fabrics (see Group IV(c)).ALSO:The crease resistance and wet strength of textile fabrics is improved by treating the fabric with a condensate of an amino compound and an aliphatic aldehyde containing one or more methylol groups.  Specified amino compounds are urea, thiourea, dicyandiamide, guanidine, aminotriazines (e.g. melamine), aminodiazines (e.g. acetoguanamine), amino-quinazolines and guanazoles.  Specified aldehydes are trimethylol acetaldehyde, dimethylolpropionaldehyde and methylolisobutyraldehyde.  In examples (1) viscose rayon fabrics are impregnated with aqueous solutions of melamine-trimethylolacetaldehyde condensates which may contain triethanolamine or glycolic acid.  The fabrics are squeezed and dried and if desired after-heated at 110 DEG C.  The fabric is also treated with an aqueous solution of an acetoguanamine-trimethylolacetaldehyde condensate and glycolic acid with or without the addition of pyridine, piperidine, or an ethanolamine; (2) a rayon fabric is impregnated with an aqueous solution of an acetoguanaminetrimethylolacetaldehyde condensate and formic acid. The fabric is dried at 70-80 DEG C and after-heated at 113 DEG C.