Patent GB-583844-A (GB)
Title: Manufacture and use of stabilised mixtures containing melamine and formaldehyde or condensation products thereof
IPC: D06M15/423
Filed: 1942-11-09
Abstract: Mixtures containing melamine and formaldehyde or a preliminary condensation product from these compounds, and an acid or an ammonium salt is stabilised by the incorporation of pyridine. Suitable aminotriazines are melamine, melam, melem, melon, ammelin, ammelide; 2-chloro-4,6, diamino-1,3,5-triazine; 2 - (p-oxyphenyl)-4,6 - diamino - 1,3,5 - triazine; 2 - phenyl - 4 - amino - 6 - oxy - 1,3,5-triazine; or alkyl, aryl or aralkyl aminotriazines.  In example 1, melamine, formaldehyde and water are refluxed together, the mixture diluted and cooled and the quaternary ammonium salt from dimethyl sulphate and 1-dimethylamino-4-stearylamino-benzene as a softening agent, ammonium chloride and pyridine are added.  The bath remains as a thin liquid for a longer time than one containing no pyridine.  It is used for imparting anti-creasing properties to a viscose fabric.  Example 2 is similar.  Example 3 describes a bath containing starch, an aqueous melamine resin prepared from 1 mol. melamine and 3 mols. formaldehyde ammonium formate and pyridine which is used to stiffen cotton calico.  Example 4 also describes a stiffening bath from the melamine resin of Example 3, formic acid and pyridine.  Example 5 describes a bath similar to that of example 4, but also containing ammonium chloride.  It may be used for rendering viscose non-shrinking or for increasing the fastness to wet treatment and in some cases to chlorine of dyeings with water-soluble dyestuffs, e.g. Cotton Yellow, Melanthrine, Direct Blue, or Chlorantine Fast Violet.  In example 6, a printing paste is prepared from a water-soluble methylol melamine, water, gum tragacanth, ammonia, an alcoholic solution of Orange R, ammonium thiocyanate and pyridine.  The stability of the paste as regards gelatinization is improved by the pyridine.  The paste is applied to white cotton material which is then steamed, washed and soaped. Example 7 describes a printing paste from an aqueous solution of a melamine-formaldehyde condensation product, Cibanone Blue paste, gum tragacanth solution, formic acid and pyridine.  The paste is printed on to cotton fabric producing prints which are fast to boiling soap treatment.  Example 8 describes a glue prepared from a melamine-formaldehyde condensation product, potato starch, citric acid and water with pyridine as a stabilising agent. Specifications 466,015, 477,841, 480,316 and 482,345 are referred to.  The Specification as open to inspection under Sect. 91 is not limited to the use of pyridine or of melamine, but includes any weak volatile organic base soluble in water as the stabiliser and covers any aminotriazine-formaldehyde condensation product. Aminotriazines mentioned are 2-chloro-4,6-diamino-1,3,5-triazine; 2-(para-oxyphenyl)-4,6-diamino-1,3,5-triazine; 2-phenyl-4-amino-6-oxy-1,3,5-triazine; triarylmelamines; mono-, di- and tri-alkylmelamines, or the corresponding aralkylmelamines; melam; melem; melon; ammelin and ammelide.  This subject-matter does not appear in the Specification as accepted.