Patent GB-744991-A (GB)
Title: An improved process for imparting dimensional stability to cellulose textile fabrics
IPC: D06M15/423
Filed: 1953-01-26
Abstract: Textile fabric composed of cellulosic materials, e.g. cotton or regenerated cellulose, or of cellulosic materials mixed with other materials, is impregnated with an aqueous solution of the reaction product of (1) pyruvic aldehyde, a substitution product thereof, a dialdehyde, e.g. glyoxal or 2-hydroxyadipaldehyde, or a compound yielding any of these, e.g. tetraethoxypropane or pentaerythritol formal, and (2) an amino- or amido-aldehyde condensation product. Excess solution is removed and the fabric is dried and heated. The reaction product may combine with the cellulose and an excess of the dialdehyde component may be present which also combines with the cellulose.  The impregnating solution contains an acid catalyst, numerous examples of which are given.  The reaction product is obtained prior to the impregnation by bringing the components together in aqueous solution and heating at temperatures exceeding 120 DEG  F.  After the reaction the solution is cooled and the catalyst and textile auxiliaries are added to the solution.  The amino- or amido-aldehyde component may be a methylolamide, a methylolamine or dimethylol urea.  In an example the impregnating solution comprises a mixture of the reaction products of glyoxal and dimethylol urea and pyruvic aldehyde and dimethylol urea.  The pH of the impregnating solution varies from 1.65 to 6.5 and the heating temperature from 280 DEG  to 305 DEG  F.  The intervening drying step may be at temperatures from 200 DEG  to 260 DEG  F.  Specification 586,637 is referred to.ALSO:Cellulosic textile fabric is impregnated with an aqueous solution containing the reaction product of pyruvic aldehyde or a substitution product thereof, or a dialdehyde (or a compound yielding any of these) and an amido- or amino-aldehyde condensation product, excess solution is removed, the fabric is dried, and the dry fabric is heated.  The dialdehyde may be glyoxal or 2-hydroxyadipaldehyde, and specified compounds which yield a dialdehyde are tetraethoxypropane and pentaerythritol diformal.  The amido- or aminoaldehyde component may be a water- or acid-soluble condensation product of urea or melamine with formaldehyde such as a methylolamide, a methylolamine or dimethylol urea.  The solution may contain an excess of the pyruvic aldehyde or dialdehyde which may react with the cellulose.  A catalyst, a plasticizer or a softening or finishing agent may be added to the solution.  The catalyst may alternatively be present as an impurity in the dialdehyde. Numerous examples of catalysts are given, these being generally acids or of acid reaction.  The pH of the treating solution may lie between 1.65 and 6.5.  The fabric may be dried at temperatures from 200 DEG  to 260 DEG F., with or without tension, and heated at temperatures from 280 DEG  to 305 DEG F.  The fabric may be composed of cotton regenerated cellulose, or mixed yarns of cotton and regenerated cellulose or mixtures of cotton or regenerated cellulose with fibres of nylon, cellulose acetate, zein, casein, ethylene glycol-terephthalic acid condensation product or acrylonitrile.  The reaction between the pyruvic aldehyde or dialdehyde and the amido- or amino-aldehyde component is performed at temperatures above 120 DEG F. and prior to the impregnation.  In one example the impregnating solution comprises a mixture of the reaction products of pyruvic aldehyde and dimethyl urea and glyoxal and dimethyl urea.  The auxiliary agents may be added with the catalyst or at any stage in the preparation of the impregnating solution.  The fabric may be after-treated by calendering or decatizing, or by neutralizing, rinsing and drying.  Specification 586,637 is referred to.