Patent GB-986073-A (GB)
Title: Woven cotton fabrics having recoverable stretch characteristics
IPC: D06M16/00
Filed: 1963-01-07
Abstract: An all-cotton woven fabric stretchable in the filling direction to from 120-130% of its finished width and capable of recovering at least 85% of such stretch, which has been produced by wetting an all-cotton woven fabric with an aqueous solution containing 15-25% by weight of sodium hydroxide, maintaining it under tension in the warpwise direction and in an untensioned condition in the filling direction while the sodium hydroxide and the warpwise tension causes it to shrink in width but not in length thereby crimping the filling yarns, washing and drying and subjecting it to the action of a thermosetting resin, formaldehyde or divinyl sulphone to stabilize the filling yarns in their crimped state, are coated with a vinyl resin, rubber pyroxylin or a polyurethane.ALSO:Widthwise recoverable stretch characteristics are imparted to allow cotton woven fabrics by (a) wetting them with an aqueous mercerizing solution of 15-20% by weight of sodium hydroxide, (b) maintaining them under tension in a warpwise direction and in an untensioned condition in the filling direction while the sodium hydroxide and warpwise tension causes them to shrink in width but not in length and thereby crimp the filling yarns, (c) washing them to remove the sodium hydroxide while applying tension in the warpwise direction but without applying tension in the filling direction, (d) drying while applying tension in the warpwise direction but without stretching in the filling direction, and (e) treating them with a chemical agent having the capacity to stabilize the filling yarns in their crimped state.  The fabrics treated may be woven from standard or normal twist cotton yarns and may have been desized by treatment with amylolytic and proteolytic enzymes and bleached.  The fabric may be impregnated with the sodium hydroxide solution and advanced through a mercerizing range under warpwise tension but free from tension in the filling direction and without using water on the tenter frame or the fabric may be impregnated with the sodium hydroxide solution by passing it in a slack width condition through a padding apparatus equipped with a saturating box and then wound on a roll for a suitable period of storage before washing.  If the widthwise shrinkage is to be limited to a predetermined amount the selveges of the fabric may be attached to appropriately adjusted pins or clips on the mercerizing tenter frame during passage there through.  The fabric may then be washed by passage through a plurality of open width washers containing water at a temperature of 160 DEG -180 DEG F. and, if desired, a small amount of acid and dried in a revolving drum or can type drier without increasing the width while still applying tension in a warpwise direction.  The fabric may then be treated with an aqueous solution of an anionic wetting agent, e.g. a sulphonated aliphatic polyester, dried and impregnated with an aqueous solution of the chemical agent used to stabilize the filling yarns, e.g. a thermo setting resin such as triazene formaldehyde and triazene formaldehyde condensates, formaldehyde, divinyl sulphone or divinyl sulphone donors, and a catalyst, e.g. magnesium chloride, dried, cured by heating to 320 DEG -340 DEG F. for 1-3 minutes washed with an aqueous solution containing an alkylphenoxy polyethyleneoxy ethanol and dried.  The fabric may be bleached prior to treatment with the sodium hydroxide although it is preferred to effect bleaching after the mercerizing step prior to application of the stabilizing agent.