COMMINGLING SELF-TWIST YARN WITH FILAMENTS

The air intermingling technique is used to impart filament cohesion in flat and textured multifilament yarns; more recently this technique h as been used to combine filaments with spun yarns or elastomers to for m composite yarns. In this investigation, a self-twist yarn was commin gled with a thin, flat, multifilament yarn using an intermingling air nozzle. The tensile properties of the commingled yarn were significant ly improved in comparison with the self-twist yarn from which the comm ingled yarn was made. Self-twist yarn is notorious for its structural periodicity, which leads to fabric patterning. This has been reduced t o almost invisibility in the commingled yarns. Experiments have also r evealed that commingling increases yarn hairiness, which may impose ad verse effects on yarn waveability. Yarn structural examination shows t hat trapping the ST yarn between the filaments and wrapping the ST and filaments together with a small portion of self-twist yarn surface fi bers are the two predominant kinds of bindings formed during commingli ng. The influences of air pressure in the commingling nozzle, yarn lin ear speed, and overfeed ratio are also reported.