Commingling Self-Twist Yarn with Filaments1

Abstract

The air intermingling technique is used to impart filament cohesion in flat and textured multifilament yarns; more recently this technique has been used to combine filaments with spun yarns or elastomers to form composite yarns. In this investigation, a self-twist yarn was commingled with a thin, flat, multifilament yarn using an inter mingling air nozzle. The tensile properties of the commingled yarn were significantly improved in comparison with the self-twist yarn from which the commingled yarn was made. Self-twist yarn is notorious for its structural periodicity, which leads to fabric patterning. This has been reduced to almost invisibility in the commingled yarns. Experiments have also revealed that commingling increases yarn hairiness, which may impose adverse effects on yarn weaveability. Yarn structural examination shows that trapping the ST yarn between the filaments and wrapping the ST and filaments together with a small portion of self-twist yarn surface fibers are the two predominant kinds of bindings formed during commingling. The influences of air pressure in the commingling nozzle, yarn linear speed, and overfeed ratio are also reported.