Novelty yarn

Novelty yarns include a wide variety of yarns made with unusual features, structure or fiber composition such as slubs, inclusions, metallic or synthetic fibers, laddering and varying thickness introduced during production. Some linens, wools to be woven into tweed, and the uneven filaments of some types of silk are allowed to retain their normal irregularities, producing the characteristic uneven surface of the finished fabric. Man-made fibres, which can be modified during production, are especially adaptable for special effects such as crimping and texturizing.

Novelty yarns are sometimes referred to as complex yarns. A yarn which makes a fabric is not always smooth and uniform. Complex yarns are the uneven yarns which may be thick and thin or have curls, loops, twists and even differently coloured areas along their length. This look of the yarns are used to add interesting effects in fabrics. In complex ply two or more complex yarns are twisted around each other to form loops, curls and knots to create fancy effects. Many knitting yarns are complex ply yarns which give interesting textures in finished products.

Bouclé, or looped, yarns are created by loosely looping an effect yarn around a base yarn. They can be made of any type of fiber and are usually composed of three plies, or strands, wrapped around each other. The texture is created by spinning one of the three plies more loosely than the other two. Fiber artists who choose to create projects in bouclé yarn must use extra care because if not handled carefully, the loose strand may split and snag on the knitting needles or crochet hook.

The soft, fuzzy surface of chenille yarns, which resemble pipe cleaners in appearance, can be created in several ways. Most commonly, a fabric is first produced and then cut into narrow strips resembling a yarn. Then, when the fabric is cut, the raw edges become very fuzzy and produce the chenille appearance. Other chenilles are created by trimming a loosely attached effect fiber to create the fuzzy appearance. Still other chenilles are created by attaching or gluing fibers to the yarn.

A yarn in which the core has been wrapped by another strand, such as of cotton or nylon around an elastic base as used in commercial socks.

The appearance of corkscrew or spiral yarns is achieved by using yarns of two different fibers and often twisting one under a different tension than the other.

Crepe yarns may be classified as fancy yarns and are created by tightening the twist given to a yarn, resulting in a kinked or looped strand.

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Wikipedia