Types of Yarns: Classification, Properties, and Uses

What Is Yarn?

From sheer hosiery and decorative fabrics to sewing thread and industrial webbing, yarns appear in products that need very different kinds of performance. The structure of a yarn affects luster, hand, bulk, strength, and surface feel, so the yarn choice matters as much as the fiber itself. Yarns may be made from long, continuous filaments or from short staple fibers that must be held together to form a continuous strand. They may also be twisted, textured, or built into decorative forms when a fabric needs more interest than a plain surface.

Classification of Yarns

The primary classification of yarns is filament or staple. After that, yarns are commonly grouped by the number of parts they contain and by the similarity of those parts. Some yarns are simple and regular, while others are made to create decorative effects. Core-spun yarns form another useful group because they combine a central core with an outer covering.

Filament Yarns

Filament yarns are made from long, continuous strands of fiber. Monofilament yarns, made from a single filament, have limited use in nylon hosiery, some open-work decorative fabrics, fabric webbing, and a variety of industrial uses. Monofilament yarns can be made by extrusion from spinnerets or by the slit-film technique. More commonly, many filaments are joined to form multifilament yarns. These yarns can be made more cohesive by twisting them together loosely or more tightly. The amount of twist, along with fiber traits such as luster, hand, and cross-sectional shape, helps determine the appearance and feel of the yarn. A loosely twisted, smooth filament yarn made from a bright fiber would show marked luster, resist pilling, and have a smooth surface. Sometimes filament yarns are also put through texturing, which modifies their feel and bulk.

Staple Yarns

Staple, or spun, yarns are made from staple-length fibers. Because the fibers are short, they must be held together before they can be formed into a long, continuous yarn. The multiple processes needed to make staple yarn add to the cost, but the comfort, warmth, softness, and appearance make these yarns highly desirable in many products. Before manufactured fibers were invented, all yarns except those made from silk had to be spun from short staple fibers. At first, these fibers were twisted together by hand. A small bunch of absorbent cotton can show this process clearly, because twisting the fibers in one direction will produce a short, coarse, but recognizable cotton yarn.

Yarns Classified by Number of Parts

Yarns classified by the number of parts are divided into single, ply, and cord yarns. Each group is defined by how many strands are twisted together and how far the yarn can be untwisted before it separates.

a) Single Yarn

A single yarn is made from a group of filament or staple fibers twisted together. If a single yarn is untwisted, it will separate into fibers. A single yarn may therefore be either a single yarn of staple fibers or a single yarn of filament fibers.

b) Ply Yarn

Ply yarns are made by twisting together two or more single yarns. If ply yarns are untwisted, they divide into two or more single yarns, which in turn can be untwisted into fibers. Each single yarn twisted into a ply yarn is called a ply.

c) Cord Yarn

Cord yarns are made by twisting together two or more ply yarns. They can be identified by untwisting the yarn to form two or more ply yarns. Cord yarns are used in making ropes, sewing thread, and cordage, and they are also woven as decorative yarns into some heavyweight novelty fabrics.

Yarns Classified by Similarity of Parts

Yarns can also be grouped according to whether their parts are uniform or intentionally varied. Simple yarns have a regular appearance, while novelty yarns are made for decorative effect.

a) Simple Yarn

Simple yarns have a uniform size and a regular surface. They may have loose, moderate, tight, or hard twist. Single, ply, and cord yarns can all be simple yarns if their components are uniform in size and have a regular surface. When one strand of fibers is twisted evenly, it is a simple single yarn. Two simple single yarns twisted together create a simple ply yarn.

b) Novelty (Fancy) Yarn

Yarns made to create interesting decorative effects in fabrics are known as novelty yarns. They may also be called fancy yarns or complex yarns. Complex yarns usually have more than one part, while novelty yarns can be single, ply, or cord, staple or filament. Most novelty yarns are weaker than their simple counterparts, so they are usually placed in the crosswise direction of woven fabrics where strength is not as critical. They can also be used in knitted or other fabric constructions to add texture and decoration. The terminology can sometimes be confusing, but the following yarns are the most commonly accepted forms.

c) Bouclé Yarn

Bouclé yarns, also called loop yarns, are multi-ply yarns. An effect yarn forms irregular loops around a base yarn, and another yarn binds or ties the effect yarn to the base. The loops remain visible in the yarn and in fabrics made from it.

d) Ratiné Yarn

Ratiné yarns are similar to bouclé in construction, except that the effect yarn is wound irregularly and more tightly around the base yarn.

e) Flake (Flock) Yarn

Flake, or flock, yarns are made of loosely twisted yarns with fibers of another color included in the structure. They give a tweed effect in a fabric.

f) Nub Yarn

Nub yarns, also known as knot or spot yarns, are ply yarns in which an effect yarn is twisted around a base yarn a number of times in a small area to create an enlarged bump, or nub. Sometimes a binder yarn is used to hold the nubs in place. The spacing of the nubs may be regular or irregular, and the nubs can be different colors than the base yarn.

g) Slub Yarn

Slub yarns may be either ply or single yarns of staple fibers. The slub effect is created by varying the twist in the yarn, allowing areas of looser twist to form. This produces a long, thick, soft area in the fabric called a slub and creates an irregular diameter along the yarn. The surface of fabrics woven with slub yarns shows these irregularities. Because slubs are produced by areas of varying twist, the yarn has weaker spots. Slubs are the same color as the rest of the yarn and cannot be pulled out of the fabric without damaging the structure of the fabric. Filament yarns can also be spun with varying degrees of twist. These yarns create a slubbed appearance in fabrics and are known as thick-and-thin yarns.

h) Spiral (Corkscrew) Yarn

Spiral, or corkscrew, yarns are made of two plies, one soft and heavy and the other fine. The heavy yarn winds around the fine yarn.

i) Chenille Yarn

Chenille yarns are made by a very different process and require several steps in their preparation. First, leno-weave fabric is woven. The fabric is then cut into strips, and these strips, which have a soft pile on all sides, are used as yarns. These are not yarns in the traditional sense of twisted fiber, but they have been through a series of preliminary stages before being readied for use.

Core-Spun Yarns

Core-spun yarns do not fall into the category of novelty yarns, but they are yarns made with a central core of one fiber around which an exterior layer of another fiber is wrapped or twisted. Core-spun yarns may be made with an elastomer core, such as spandex, covered by another fiber to produce a stretch yarn. Other core-spun yarns include sewing thread made with polyester cores and cotton cover.

Comparison of Different Types of Yarns

Filament yarns are made from long, continuous strands, while staple yarns are made from short fibers that must be held together to form a yarn. Single, ply, and cord yarns differ mainly by the number of parts twisted together. Simple yarns stay uniform in size and surface, while novelty yarns are deliberately varied to create decorative effects. Core-spun yarns are different again because they combine a central core with an outer covering.

Applications of Different Types of Yarns

Filament yarns are used where a smooth surface or sheer effect is wanted, such as nylon hosiery, open-work decorative fabrics, fabric webbing, and a variety of industrial uses. Cord yarns are useful in ropes, sewing thread, and cordage, and they also appear as decorative yarns in heavyweight novelty fabrics. Novelty yarns are used to add texture and decoration in woven or knitted fabrics, especially when the yarn is placed crosswise in woven structures. Core-spun yarns are used for stretch yarns and for sewing thread made with polyester cores and cotton covers.

Conclusion

Yarns may look simple at first glance, but their structure changes the way a fabric performs and feels. Filament and staple yarns form the broad base of classification, while single, ply, and cord yarns describe how many parts are twisted together. Simple yarns keep a regular appearance, and novelty yarns bring texture, interest, and decorative value. Core-spun yarns add another useful option by combining a central core with an outer covering. As textile design continues to balance performance with appearance, yarn selection will remain one of the most practical decisions in product development.

Frequently Asked Questions (FAQ)

1. What are the primary types of yarns?

The primary classification of yarns is filament or staple.

2. What is the difference between single, ply, and cord yarns?

A single yarn is made from one group of fibers twisted together, a ply yarn is made by twisting two or more single yarns together, and a cord yarn is made by twisting two or more ply yarns together.