Patent GB-458038-A (GB)
Title: Improvements in or relating to the treatment of yarns and similar materials
IPC: D02G1/00
Filed: 1935-06-13
Abstract: Crinkle effects are produced on yarns, ribbons, and the like, the composition of which on one side of a medial longitudinal plane differs from the composition on the other side, by subjecting them to treatment with a swelling medium so that the materials are swollen to a greater extent on one side of the medial longitudinal plane than on the other side.  In a modification, the yarns, ribbons, or the like are subjected to a non-uniform swelling treatment on opposite sides of a medial longitudinal plane.  The swelling may be non-uniform with respect to threads as a whole, but is preferably non-uniform with respect to the individual components of the threads.  The non-uniform swelling may be obtained by applying a resist to one side only of a number of filaments in parallel formation and thereafter drying them and passing them through a swelling agent.  The resist may be p applied by means of a wick or longitudinally grooved rollers. Preferably, the resist is applied at intervals to one side of the filament and at intermediate positions on the opposite side of the filament.  In another method the materials are impregnated with a swelling agent under such conditions that little or no swelling occurs, and then are passed under and close to a hot plate. Suitable heterogeneous materials for use in the process may be produced by treating a regenerated cellulose filament alternately on opposite sides with a resist, passing through a solution of a cellulose derivative, and then removing the resist.  Again, a solution of a suitable substance may be applied alternately on opposite sides by means of grooved rollers, or filaments of a saponifiable cellulose ester may be treated with a saponifying paste to obtain a material which is saponified alternately first on one side and then on the other.  Again, a paste containing an esterifying agent thickened, e.g. with trimethyl cellulose may be similarly applied to a cotton or regenerated cellulose yarn.  Any of these heterogeneous materials may be crinkled by treatment with a swelling agent for the substance applied to or formed in or on the core.  When bundles of filaments are treated by the process they may be subjected to an operation to displace the crinkles in the individual filaments with relation to each other.  The crinkled continuous filaments may be cut up into short lengths and spun into yarns, e.g. as described in Specifications 424,683, 424,752, 424,830, and 424,879, [all in Group IX].  The crinkle may, if desired, be fixed in the products by treatment with artificial resins, e.g. by the process described in Specification 455,021.  Examples are given of the saponification of cellulose acetate yarns alternately on opposite sides, followed by drying, washing, stapling, and swelling in aqueous acetone, and of the application of a shellac resist alternately to opposite sides of cellulose acetate yarns, followed by swelling in a solution of methylene chloride in benzene.  The process is applicable to yarns having a having a basis of cotton, silk, fibroin, albuminous compounds, polymerized vinyl compounds, and particularly of regenerated cellulose and of organic derivatives of cellulose.