As the name implies, a core-wrap yarn is composed of a central core of a function-specific synthetic fiber and a sheath (wrap) of 100% wool fibers or any combination of wool blends we spin. The core and sheath firmly adhere with each other and do not strip or slip during processing or usage. Using lycra®/ Spandex® as the core of the yarn offers stretch to the yarn, while the sheath provides the traditional properties of 100% Merino Wool. Thus, the garments made with these core yarns, can offer manufacturers the abilaity to add lycra®/ Spandex® to a yarn without worring about matching the lycra®/ Spandex® to the colour of the wool yarn since the wool fibers are spun around the lycra®/ Spandex® covering it completely. The stretch yarn will not show until the yarn has been broken.
For knitters of socks, using a core spun yarn is convenient as the operator of the machines dosen’t have to worry about feeding the lycra®/ Spandex® into the sock. If socks are knitted with a stretch yarn and the stretch yarn breaks, then you are left with a defective sock. By using the core spun wool yarn with lycra®/ Spandex®, you never have to worry about 2nd quakity goods.
For knitters, using a copre-spun yarns, they can manufacture garments with a lot more stretch than what the natural fibers can give. It makes the garments more snug to the body and gives the consumer a garment that is more flexible and adhers to the shape of the body better.